Apollo Flight Journal logo
Previous Index Next
Launch and Reaching Earth Orbit Journal Home Page Transposition, Docking and Extraction

Apollo 15

Earth Orbit and Translunar Injection

Corrected Transcript and Commentary Copyright © 1998-2023 by W. David Woods and Frank O'Brien. All rights reserved.
Last updated 2023-10-27
Index to events
AOS at Canary Islands 000:17:06 GET
Optics dust cover jettison 000:44:57 GET
AOS at Carnarvon 000:51:56 GET
AOS at Goldstone 001:29:10 GET
TLI plus 90 abort PAD 001:31:16 GET
TLI PAD 001:38:07 GET
Go for TLI 002:29:52 GET
Time Base 6 indication 002:40:27 GET
TLI burn begins 002:50:03 GET
S-IVB shut down called 002:55:56 GET
Apollo 15 has reached a parking orbit 170 kilometres or 93 nautical miles above Earth. This is a very low altitude for an Earth orbit but since the stack will make less than two revolutions, the decay in their altitude is of no consequence. While they are in this orbit, the crew will check their spacecraft as much as possible, following a list of items in the Launch Checklist, beginning at page L2-11.
000:16:56 Worden (onboard): The first Line Heater's On.
000:16:58 Scott (onboard): Okay. Have you got the torquing angle?
000:17:02 Worden (onboard): Mm-hum. Okay, we could do the SM RCS monitoring check and the CM...
[Download MP3 audio file. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
We've had Loss Of Signal through Bermuda. About a minute out of Canary Islands. To recap a moment, the measured orbital... here is a call now to the crew.
000:17:06 Fullerton: Apollo 15, Houston through Canaries. Over.
000:17:10 Scott: Go ahead, Houston, 15.
000:17:12 Fullerton: Roger. You're loud and clear.
000:17:16 Scott: Okay. The S-IVB tank pressures are - about 41 [psi] on the oxidizer and about 21 [psi] on the fuel.
000:17:21 Fullerton: Roger; 41 and 21.
Long Comm Break.
000:17:42 Irwin (onboard): I know we're over the [garble] but [garble] Indian Ocean should be.
000:17:45 Worden (onboard): Okay.
000:17:46 Scott (onboard): And it looks like the S-IVB is tracking very nicely.
000:17:51 Worden (onboard): [Garble] we were going so fast.
000:17:53 Scott (onboard): Huh?
000:17:54 Worden (onboard): I - I guess I hadn't really - hadn't - myself thought we wouldn't be - it wouldn't be visibly this fast.
000:18:05 Scott (onboard): Oh...
Apollo 15 [is] in a 92.5 by 91.5 nautical mile [171.3 by 169.5 km] Earth orbit. 1 [nautical] mile [1.85 km] out of perfectly circular. Communications through the Canary Island tracking station for about 4 minutes and 11 seconds total pass time.
The parking orbit around Earth does not permit continuous communication with Mission Control. Indeed, the orbit is so low that when the spacecraft does come within range of a station, it is only above the horizon for a short period of time, even if it passes directly overhead. If it passes to one side or the other, the period of contact is further constrained; for this pass over the Canary Islands tracking station, communication lasts only 4 minutes and 11 seconds.
[Download MP3 audio file. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Coming up on Loss Of Signal through Canaries.
The Insertion and Systems checklist is split into 30 main sections covering 8 pages. The crew's workload is very high as there is a limited amount of time available to ensure the spacecraft and booster are fit to continue on to the Moon. Section 1, now completed, deals with shutting down the S-IVB control systems until they are needed again for the boost to the Moon, and checking that the booster's fuel and oxidizer pressures are within limits. The checklist includes a note, that after section 1, the other sections are not sequential; i.e. one section does not depend on others having been completed. However, Dave's comm later will suggest they are following the checklist items in the order they appear.
Scott, from 1998 correspondence: "These are set up in an optimum sequence before flight, and very seldom deviated. The checklist is normally followed precisely, to ensure there are no surprises."
000:21:23 Fullerton: 15, Houston. About 35 seconds to LOS [Loss Of Signal], and we have nothing further for you. We'll see you at Carnarvon, as shown on the checklist, at 52 [minutes GET]. Over.
000:21:34 Scott: Okay. Carnarvon at 52.
Very long Comm Break.
000:21:38 Worden (onboard): Okay. I'm going to do a fuel cell purge check here, Dave.
000:21:41 Scott (onboard): Okay. Al, we'll put a...
Flight Dynamics Officer reports that the data coming from the Canary Islands tracking station confirms the initial measurements of the Earth parking orbit, and we're expecting to acquire Apollo 15 again over the Carnarvon, Australia, tracking station at 52 minutes Ground Elapsed Time, about 30 minutes from now. And at 22 minutes, 13 seconds Ground Elapsed Time; this is Apollo Control.
000:21:45 Irwin (onboard): Go ahead.
000:21:46 Worden (onboard): Huh?
000:21:47 Scott (onboard): Do you want to get - get going down there?
000:21:49 Worden (onboard): Yes.
000:21:50 Scott (onboard): Go slow.
000:21:51 Worden (onboard): Yes.
000:21:57 Scott (onboard): Try and clean some of this stuff off, too.
000:22:02 Worden (onboard): Ah, oh, eat it.
000:22:10 Scott (onboard): You can take mine and stick it in there, too.
000:22:12 Worden (onboard): Yes.
000:22:13 Irwin (onboard): With that indicator out, I can't confirm an H2 purge on fuel cell 2.
000:22:19 Scott (onboard): Really?
000:22:20 Worden (onboard): Can't you get the - get the H2...
000:22:26 Scott (onboard): Caution and warning tone?
000:22:27 Worden (onboard): No, we don't get it.
000:22:29 Worden (onboard): Hmm.
000:22:30 Scott (onboard): Hmm. Better discuss that with them next time we...
000:22:32 Irwin (onboard): Yes.
000:22:34 Scott (onboard): ...go by.
000:22:53 Scott (onboard): Well, shall we gently step along?
000:22:55 Worden (onboard): Yes.
000:22:56 Worden (onboard): Yes. Do you want R-12 out now, Jim? Anything Flight-Data-File-wise that you need now?
000:23:04 Irwin (onboard): I don't need anything, Al.
000:23:06 Worden (onboard): Okay. I'm just going to stick these cards here in the compartment then, and...
000:23:18 Irwin (onboard): Okay, Dave. Do you want to swing over and get the SM RCS monitoring check? Or do you want me to get that?
000:23:23 Scott (onboard): Oh, I can get it.
000:23:24 Irwin (onboard): Here. I can just read it to you.
000:23:27 Scott (onboard): Shoot.
000:23:28 Irwin (onboard): SM RCS Propellant talkback, eight, gray.
000:23:30 Scott (onboard): Eight, gray.
000:23:31 Irwin (onboard): RCS Helium1 and 2...
000:23:32 Scott (onboard): Whoops, stand by; we got one - one barber pole right down - we got B Propellant - barber pole. That was probably a mistake. We open it, and it's gray.
000:23:46 Irwin (onboard): You want to make a note?
000:23:48 Scott (onboard): Yes.
000:23:49 Irwin (onboard): B Propellant...
000:23:50 Scott (onboard): B Secondary Propellant - B Sec Propellant was barber pole, and it reset to gray.
000:23:58 Irwin (onboard): Okay. Okay. SM RCS Indicator, Helium Tank Temp.
000:24:05 Scott (onboard): Okay. Helium Tank Temp.
000:24:06 Irwin (onboard): RCS Indicator selector to A through D. Give me Package Temp, Helium Pressure - all four.
000:24:15 Scott (onboard): Okay. Let me get calibrated here. You want - That's in temperatures only, huh?
000:24:21 Irwin (onboard): No, I want Temp, Pressure, [garble] Pressure, and Helium Tank Temp.
000:24:26 Scott (onboard): Okay. 140, 4000, 200, 71.
000:24:32 Irwin (onboard): Good.
000:24:34 Scott (onboard): 150, 4000, 195, 70.
000:24:39 Irwin (onboard): Good.
000:24:41 Scott (onboard): 140, 4200, 195, 74.
000:24:46 Irwin (onboard): Good. D.
000:24:48 Scott (onboard): D is 150, 4000, 190, and 72.
000:24:55 Irwin (onboard): Okay, your Manifold Pressure's too low.
000:24:59 Scott (onboard): Say again?
000:25:00 Irwin (onboard): The Manifold Pressure on D is a little low, about 2.
000:25:03 Scott (onboard): Oh.
000:25:04 Irwin (onboard): Its lower - lower limit is, accord - 192.
000:25:08 Scott (onboard): Oh, okay, I'll give you one - Well, shoot, [garble]...
000:25:10 Irwin (onboard): You can't read it. Okay. CM RCS monitoring check.
000:25:12 Scott (onboard): Okay.
000:25:13 Irwin (onboard): CM RCS Propellant talkback, two, gray.
000:25:15 Scott (onboard): Two, gray.
000:25:16 Irwin (onboard): RCS Indicator, switch to CM 1 and 2.
000:25:20 Scott (onboard): Okay. CM 1 - I'm waiting - Okay, you want...
000:25:23 Irwin (onboard): Helium Temp, Pressure and Manifold Pressure.
000:25:26 Scott (onboard): Okay. Helium Temp's about 70...
000:25:31 Irwin (onboard): Good.
000:25:32 Scott (onboard): ...4000, and 95.
000:25:37 Irwin (onboard): Okay, Helium should be 4100 to 4200.
000:25:39 Scott (onboard): Okay, it's right on 4000.
000:25:41 Irwin (onboard): Okay. Okay. For 2?
000:25:45 Scott (onboard): Two; I'm looking at 70, 4000, and about 90.
000:25:52 Irwin (onboard): Okay. Okay. I'm going to do a Caution and Warning operational check here.
000:25:59 Scott (onboard): Okay.
000:26:06 Irwin (onboard): We're going to get a Master Alarm here.
000:26:16 Scott (onboard): Okay, let me check.
000:26:18 Irwin (onboard): Okay, you're down in the LEB, Al?
000:26:20 Worden (onboard): Yes.
000:26:21 Scott (onboard): Get those...
000:26:22 Irwin (onboard): Okay, can you get the strut unlocked while you're getting those?
000:26:23 Scott (onboard): I'm getting them right - I'm getting them right now.
000:26:25 Irwin (onboard): Okay.
000:26:40 Worden (onboard): That was a fantastic ride! [Laughter.]
000:26:45 Worden (onboard): I'm just now beginning to understand what went on.
000:26:47 Irwin (onboard): Yes, boy.
000:26:49 Worden (onboard): That S-IC really does shake!
000:26:52 Scott (onboard): Yes.
000:26:54 Irwin (onboard): Are you still working on that, Al?
000:26:56 Worden (onboard): Got the lanyard low - stowed.
000:26:58 Irwin (onboard): Okay. Drinking Water Supply valve, On.
000:27:00 Worden (onboard): Okay. See if I can get to it here.
000:27:04 Scott (onboard): Quit having a good time and go to work. [Laughter.]
000:27:13 Worden (onboard): Okay, it's On.
000:27:15 Irwin (onboard): Okay. CB: COAS/Tunnel Lighting, Main B, closed.
000:27:18 Worden (onboard): Get your big foot out of the way.
000:27:21 Scott (onboard): Push me down.
000:27:22 Worden (onboard): I did. Okay. It's closed.
000:27:24 Irwin (onboard): Okay. Unstow helmet bags, accessory bags, and tool E.
000:27:27 Worden (onboard): Okay. David, the helmet bags - Let's see, they're behind you, aren't they?
000:27:31 Scott (onboard): Yes, they're - I got to get those stupid things.
000:27:33 Irwin (onboard): They're in U-4 - or U-1. Tool E is in L-2.
000:27:38 Scott (onboard): Yes. I'll get it. I don't know what this little thing is here, [garble].
000:27:47 Irwin (onboard): Okay, I'm going to switch around and get that window cover.
000:27:51 Scott (onboard): Okay. Let's see, where the heck is tool E? [Garble]. Here it is.
000:28:06 Irwin (onboard): [Laughter.] I didn't see the - the decal on the light over here.
000:28:10 Worden (onboard): On the light?
000:28:11 Irwin (onboard): Yes. "This vehicle will not be placed in motion until all seat belts are properly fastened. By order of the Chief of Staff, USAF."
000:28:16 Scott (onboard): Oh, you didn't see that? [Laughter.]
000:28:17 Irwin (onboard): No.
000:28:29 Irwin (onboard): It would sure be easy to knock some switches here.
000:28:31 Worden (onboard): Yes. It sure would be. Okay, that's a thing we got to watch pretty close, huh?
000:28:35 Scott (onboard): Yes.
000:28:36 Irwin (onboard): I - I might get you to get that window shade, Al, if - if you have a chance.
000:28:42 Worden (onboard): Oh, it's in the...
000:28:43 Irwin (onboard): I know where it is - it's just hard for me to get over to one of them - [garble] below it...
000:28:46 Worden (onboard): I'll get it. Yes.
000:28:47 Scott (onboard): Is it in with the other window shade?
000:28:48 Irwin (onboard): Yes.
000:28:49 Worden (onboard): Yes.
000:28:50 Scott (onboard): I can get it, it's right in here.
000:28:51 Irwin (onboard): We want to put that in here so we don't get sunburned.
000:28:52 Scott (onboard): Good boy.
000:28:56 Irwin (onboard): Give us the Lexan.
000:28:57 Worden/Scott (onboard): Yes.
000:28:58 Scott (onboard): [Garble]. Okay, there's tool E.
000:29:02 Worden (onboard): Now, let's see. You want to do that Emergency Cabin Pressure thing?
000:29:08 Irwin (onboard): Yes, let me - I've got a - I'm confirming normal suit and cabin pressure.
000:29:12 Worden (onboard): Okay.
000:29:13 Scott (onboard): Here's your Lexan, Jim.
000:29:15 Irwin (onboard): Okay.
000:29:16 Scott (onboard): Got it?
000:29:17 Worden (onboard): Be very careful of that Lexan, because I - I'm going to need to take some pictures through it.
000:29:21 Irwin (onboard): Yes, okay.
000:29:25 Scott (onboard): Make sure you get everything tied down when you get through using it, because we got one more little g-level thing to go through here.
000:29:32 Worden (onboard): Yes, right.
000:29:46 Scott (onboard): Okay. Helmets and access - helmet bags and accessory bags.
000:29:50 Worden (onboard): Right here.
000:29:55 Irwin (onboard): Okay. The Lexan shade is on.
000:29:57 Worden (onboard): And grab the TSBs while you're there, too. Dave.
The TSBs are Temporary Stowage Bags.
000:30:01 Scott (onboard): Okay.
000:30:02 Worden (onboard): Okay, Jim. I guess we could do the...
000:30:06 Scott (onboard): Where are the TSBs, Al? They're not up here. They're down in one of those other things.
000:30:22 Worden (onboard): Must be in U-1.
000:30:23 Scott (onboard): Really?
000:30:24 Worden (onboard): Yes.
000:30:27 Scott (onboard): In U-1 - I was looking in U-2?
000:30:30 Worden (onboard): Oh, okay.
000:30:32 Irwin (onboard): Let's see. The O2 flow is high.
000:30:34 Worden (onboard): What's the cabin pressure...
000:30:35 Irwin (onboard): Oh, it - it just dropped down.
000:30:36 Scott (onboard): Yes. Okay.
000:30:37 Worden (onboard): What's - what's the cabin pressure? We still got the waste stowage vent...
000:30:38 Irwin (onboard): Yes. It's [garble].
000:30:39 Scott (onboard): It's 6.
000:30:40 Irwin (onboard): Well, it was just high for a little bit.
000:30:41 Worden (onboard): Yes.
000:30:42 Irwin (onboard): Okay. Cabin Pressure - Emergency Cabin Pressure valve to Both, Al.
000:30:48 Worden (onboard): Okay. Emergency Cabin Pressure going to Both.
000:30:50 Irwin (onboard): And Suit Circuit Return Value, Open, Dave.
000:30:55 Scott (onboard): Yes, sir. It's open.
000:31:00 Irwin (onboard): Okay. We can - I got the window cover on. We can remove helmet and gloves and stow in PGA bag.
000:31:05 Scott (onboard): Don't we - don't we do a check first?
000:31:08 Irwin (onboard): No, we don't. That Main Reg[ulator] check's on the next page.
000:31:11 Scott (onboard): Well...
000:31:12 Irwin (onboard): As long as you're in position though, Al, let's do it.
000:31:13 Worden (onboard): Yes.
000:31:14 Scott (onboard): Let's do it.
000:31:15 Irwin (onboard): Okay. Main Reg B valve, closed.
000:31:17 Worden (onboard): Main Reg B, closed.
000:31:18 Irwin (onboard): Emergency Cabin Pressure, select to 1.
000:31:20 Worden (onboard): 1.
000:31:21 Irwin (onboard): Push To Test pushbutton, push for O2 Flow increase.
000:31:23 Worden (onboard): Okay.
000:31:30 Worden (onboard): Don't see anything.
000:31:31 Irwin (onboard): There it goes...
000:31:32 Scott (onboard): Okay. There it goes.
000:31:33 Worden (onboard): Okay.
000:31:34 Irwin (onboard): Okay. Main Reg B valve, Open.
000:31:35 Worden (onboard): Open.
000:31:36 Irwin (onboard): Main Reg A valve, closed.
000:31:37 Worden (onboard): Closed.
000:31:38 Irwin (onboard): Emergency Cabin Pressure, select to 2.
000:31:40 Worden (onboard): To 2.
000:31:41 Irwin (onboard): Push To Test pushbutton, push for O2 Flow increase.
000:31:44 Worden (onboard): Okay. Pushing. I got it.
000:31:47 Irwin (onboard): Okay, Main Reg A valve, Open.
000:31:49 Worden (onboard): Open.
000:31:50 Irwin (onboard): Emergency Cabin Pressure, select to Both.
000:31:52 Worden (onboard): Both.
000:31:53 Irwin (onboard): Okay. That's complete.
000:31:55 Scott (onboard): Okay.
000:31:56 Irwin (onboard): So, we - you want to take off helmets and gloves now?
000:31:58 Scott (onboard): Yes.
000:31:59 Worden (onboard): [Garble], yes.
000:32:01 Scott (onboard): Cabin pressure look good?
000:32:02 Irwin (onboard): Yes.
000:32:03 Scott (onboard): Okay. Let's get into our little home. Shall we do it?
000:32:23 Worden (onboard): The accessory bags inside here, Dave?
000:32:25 Scott (onboard): Yes.
000:32:26 Worden (onboard): Let's see, you're C.
000:32:27 Scott (onboard): Okay, thank you.
000:32:28 Worden (onboard): And let's see what kind of label you got on yours today. Jim, you got an R - for you today.
000:32:36 Irwin (onboard): R, okay.
000:32:40 Scott (onboard): R, C, and L. Guess we can keep track of that.
000:32:52 Irwin (onboard): It's so pretty out here, Dave, I'd almost settle for an Earth-orbit mission.
000:32:56 Scott (onboard): Don't you say that.
000:32:57 Worden (onboard): [Laughter.]
000:33:00 Scott (onboard): Well, you'll get one, maybe someday. Who knows?
000:33:18 Worden (onboard): Boy. Sure doesn't take much to scratch these helmets.
000:33:23 Scott (onboard): No. Sure doesn't.
000:33:30 Worden (onboard): Oh, it's quiet.
000:33:32 Irwin (onboard): Sure is.
000:33:34 Worden (onboard): Let's see, what have we got going, just the suit fans?
000:34:09 Irwin (onboard): It's so quiet, it's kind of eerie...
000:34:11 Worden (onboard): Yes.
000:34:12 Irwin (onboard): Almost like a space flight.
000:34:18 Worden (onboard): [Singing.]
000:34:19 Scott (onboard): Okay. We got to snap these things [garble].
000:34:24 Worden (onboard): Yes. We're supposed to try to keep them up there where we can get them [garble].
000:34:29 Scott (onboard): You give me a hand here, will you?
000:34:30 Worden (onboard): Yes, we'll give you one.
000:34:32 Irwin (onboard): [Garble] onboard [garble].
000:34:40 Scott (onboard): [Garble] convenient place [garble].
000:34:45 Worden (onboard): Yes.
000:34:47 Irwin (onboard): [Garble].
000:34:53 Worden (onboard): [Garble].
000:35:08 Irwin (onboard): You want to [garble] them all?
000:35:10 Scott (onboard): I guess...
000:35:11 Worden (onboard): [Garble] all [garble] put them up.
000:35:20 Worden (onboard): I'll never do this again.
000:35:28 Scott (onboard): I'll bet you would [laughter].
000:35:30 Worden (onboard): Oh, what a joy! [Laughter.] Oh, what a joy!
000:35:34 Scott (onboard): You don't [garble] to mind it.
000:35:35 Worden (onboard): What a joy! Too much [garble].
000:35:40 Scott (onboard): Let's see. If you're going to do that, hand me the checklist...
000:35:42 Worden (onboard): Okay. What do we - what do we need, Dave? Why don't you read it out to me now? [Garble].
000:35:47 Scott (onboard): DAC.
000:35:48 Worden (onboard): Got magazine Able.
000:35:50 Scott (onboard): Able. Okay.
16-mm magazine A will be used to film the approach and dock with the Lunar Module currently housed in a shroud between the S-IVB, the IU and the CSM.
000:35:51 Worden (onboard): Okay, which lens?
000:35:52 Scott (onboard): Power cable, 18-millimeter lens.
000:35:54 Worden (onboard): 18-millimeter lens. Okay, 18 lens.
000:36:09 Scott (onboard): Right-angle mirror.
000:36:10 Worden (onboard): Right-angle mirror.
000:36:12 Scott (onboard): Assemble and mount in the left-hand window [garble].
000:36:16 Worden (onboard): Left hand [garble]. Okay, [garble] need to get out of here [garble].
000:36:29 Scott (onboard): Here's the mirror.
000:36:31 Worden (onboard): [Garble] the power cable.
000:36:39 Irwin (onboard): Okay, Dave, When you get a chance, you want to monitor Secondary Accumulator Quantity.
000:36:45 Worden (onboard): Now - do you want to get the Hasselblad out?
000:36:49 Scott (onboard): Oh, yes. Yes, we want...
000:36:51 Worden (onboard): It's got a mag.
000:36:53 Scott (onboard): Well, better cross it out. [Garble].
000:36:55 Worden (onboard): Mag M. Oh, it is crossed out?
000:37:00 Scott (onboard): [Garble] EL. Oh, okay. Spotmeter. Stow in the LMP TSB. I guess you better get the TSBs out [garble]...
000:37:08 Worden (onboard): Yes.
000:37:10 Scott (onboard): And the TSBs are up behind Jim.
000:37:12 Worden (onboard): Yes. Yes. They're behind you, Jim.
000:37:15 Irwin (onboard): What, the TSBs?
000:37:16 Worden (onboard): Yes.
000:37:17 Irwin (onboard): Up over here?
000:37:22 Worden (onboard): Guess that's all we need out of here for now. [Garble].
000:38:04 Irwin (onboard): Boy, you really get a Coriolis effect by looking at that [garble] in here.
000:38:08 Scott (onboard): Yes; that's why I say, just go slow, because it will all go away here in a few hours. Won't even notice it. [Garble]...
000:38:14 Irwin (onboard): [Garble] always felt we'd parted some company, didn't you?
000:38:17 Worden (onboard): Yes.
000:38:18 Scott (onboard): No, but it's nice to just go slow.
000:38:20 Worden (onboard): Yes. Oh, yes, it's...
000:38:21 Irwin (onboard): Are you ready for some TSBs?
000:38:23 Worden (onboard): Yes, you need yours most of all.
000:38:25 Irwin (onboard): I - I need mine?
000:38:26 Worden (onboard): Yes, because you need to put these two cameras in it.
000:38:29 Irwin (onboard): Okay.
000:38:43 Irwin (onboard): Okay. You want to hand me the camera, Al?
000:38:46 Worden (onboard): Okay, Jim, that's the - Yes, here you go.
000:38:49 Irwin (onboard): Is that for my UV work?
000:38:51 Worden (onboard): Your EL with magazine M in it.
000:38:54 Irwin (onboard): For the UV?
000:38:55 Worden (onboard): Yes. Okay. And here's your spotmeter.
000:39:00 Irwin (onboard): Spotmeter go in here, too?
000:39:02 Worden (onboard): Yes. Got it? Okay. I'll get the TV camera out.
000:39:36 Irwin (onboard): Okay, I'm going to do the - Dave, are you ready for that leak...
000:39:39 Scott (onboard): Yes.
000:39:40 Irwin (onboard): ...that secondary Rad leak check?
000:39:41 Scott (onboard): Yes, sir.
000:39:42 Irwin (onboard): Okay. If you'll - put the Secondary Glycol To Rad valve, Normal, for 30 seconds.
000:39:48 Scott (onboard): Have, you got tool E?
000:39:50 Worden (onboard): Yes. Yes, it's right up in front of you there, Dave.
000:39:53 Scott (onboard): Oh, thank you. Jimmy? Can you reach here?
000:39:57 Irwin (onboard): No. And it's starting to get dark.
000:40:02 Scott (onboard): Really? I've got to get going on the P52.
000:40:05 Worden (onboard): Yes.
000:40:08 Scott (onboard): Okay. I can't get that, Jim, until Al closes the door there.
000:40:11 Worden (onboard): Yes; okay.
000:40:13 Irwin (onboard): I'll do this ECS Postinsertion Configuration.
000:40:16 Scott (onboard): Okay.
000:40:17 Irwin (onboard): Okay. Glycol Reservoir Bypass valve to Open.
000:40:20 Scott (onboard): Okay, Open.
000:40:21 Irwin (onboard): Glycol Reservoir Out valve, Close.
000:40:23 Scott (onboard): Closed.
000:40:24 Irwin (onboard): Glycol Reservoir In valve, Closed.
000:40:25 Scott (onboard): Closed.
000:40:26 Irwin (onboard): And the Prim quantity, let me check it - 25 to 50 at - It's good.
000:40:34 Scott (onboard): Okay.
000:40:35 Irwin (onboard): Al, let's - Can you reach the Prim Accumulator Fill valve?
000:40:38 Worden (onboard): Yes.
000:40:39 Irwin (onboard): Okay, put it On.
000:40:47 Worden (onboard): Here, Jim, can you reach the cable? [Garble].
000:40:51 Irwin (onboard): Yes. I've got it now.
000:40:52 Worden (onboard): Okay.
000:40:57 Irwin (onboard): You working on that one, Dave?
000:40:59 Scott (onboard): Sure am.
000:41:02 Worden (onboard): Can you get to it there, Dave?
000:41:06 Scott (onboard): Haven't yet; No. Can you get to it?
000:41:12 Worden (onboard): Well, what do you need? Primary Accum?
000:41:15 Scott (onboard): Yes.
000:41:16 Worden (onboard): Yes, sure. Which way do you want it?
000:41:22 Scott (onboard): Well, it was the Primary Accumulator Fill valve...
000:41:25 Worden (onboard): Primary Accumulator Fill; okay.
000:41:26 Scott (onboard): [Garble].
000:41:28 Irwin (onboard): Put it On. I'll tell when to - put it back...
000:41:34 Worden (onboard): Turn it On?
000:41:35 Irwin (onboard): Okay...
000:41:36 Worden (onboard): It's On.
000:41:37 Irwin (onboard): ...you can turn it back Off.
000:41:38 Worden (onboard): Okay, it's Off. Is that all?
000:41:40 Scott (onboard): Yes. Why don't you get the secondary while you're there? Jim, do you have that?
000:41:43 Irwin (onboard): Yes. Secondary Glycol To Rad valve, Normal, Al, if you're in that position. Let me know when you - when you get it in Normal.
000:41:50 Worden (onboard): Yes, I can't quite reach that.
000:41:51 Scott (onboard): Okay.
000:41:54 Worden (onboard): Can you get it there, or...
000:41:55 Scott (onboard): Yes.
000:41:56 Worden (onboard): If you'll wait a minute, I'll be able to get it.
000:41:57 Scott (onboard): I can get it. Thank you.
000:41:58 Worden (onboard): Okay.
000:42:00 Irwin (onboard): Let me know when you get it to Normal.
000:42:04 Scott (onboard): Okay, going Normal now, Jim.
000:42:06 Irwin (onboard): Okay.
000:42:07 Scott (onboard): It's in Normal.
000:42:15 Worden (onboard): Okay, Jim. Here are the lines to the TV.
000:42:20 Irwin (onboard): Wish I had a place to set that thing.
000:42:22 Worden (onboard): Yes. [Garble].
000:42:23 Irwin (onboard): Okay. [Garble] the monitor.
000:42:26 Scott (onboard): Okay. How long you want this thing in Normal?
000:42:28 Irwin (onboard): Oh, I'll give you a hack here.
000:42:29 Scott (onboard): Oh.
000:42:36 Irwin (onboard): Okay...
000:42:37 Irwin (onboard): Mark. It's - Secondary, looks okay.
000:42:40 Scott (onboard): Okay, I'm back to Bypass.
000:42:41 Irwin (onboard): Okay.
000:42:42 Scott (onboard): Is that right?
000:42:43 Irwin (onboard): Right. Bypass.
000:42:46 Worden (onboard): Dave, can I hand you the monitor over there?
000:42:48 Scott (onboard): What - Oh, yes...
000:42:50 Worden (onboard): For the TV.
000:42:52 Irwin (onboard): Let me - Let's see, I got ECS Rad Flow Control to Power; Prim Glycol To Rad valve, Normal.
000:42:58 Scott (onboard): Glycol To Rad valve, Normal. [Garble]?
000:43:05 Worden (onboard): I got that. ECS Rad Flow Control, Power.
000:43:08 Scott (onboard): Oh. Okay, it's Normal.
000:43:10 Irwin (onboard): Okay. You've got Prim Glycol To Rad valve, Normal...
000:43:13 Scott (onboard): Okay.
000:43:14 Irwin (onboard): ...Rad Heater going to Prim 1.
000:43:15 Scott (onboard): Okay.
000:43:17 Irwin (onboard): ECS Rad talkback is gray. Glycol Evap Temp In, going Auto.
000:43:26 Worden (onboard): Okay, who can give me a checklist so I can do these optics?
000:43:28 Scott (onboard): Here you go.
000:43:29 Worden (onboard): Okay, I...
000:43:30 Irwin (onboard): Potable Water Heater to Main A. Okay. ECS Postinsertion Configuration complete.
000:43:36 Scott (onboard): Okay.
000:43:37 Worden (onboard): [Garble].
000:43:38 Irwin (onboard): Give you this monitor, Dave.
000:43:41 Scott (onboard): Okay.
000:44:03 Scott (onboard): What else you got on there, Jim? Oh, the TSBs.
000:44:08 Irwin (onboard): Yes, do you want a TSB?
000:44:09 Scott (onboard): Yes.
000:44:10 Irwin (onboard): I'll get them out. Do you want to put one up on the...
000:44:14 Scott (onboard): That'll do. [Garble]...
000:44:15 Irwin (onboard): Down there, Al. You...
000:44:16 Scott (onboard): [Garble]. Okay.
000:44:17 Irwin (onboard): Okay. I've got an EPS monitoring check here; secondary glycol loop check, and we've got the cameras out already.
000:44:27 Scott (onboard): Al, you want to check that?
000:44:29 Irwin (onboard): I'm going to go through a secondary glycol loop check here.
000:44:31 Scott (onboard): Okay.
000:44:41 Scott (onboard): Hey, Al?
000:44:42 Worden (onboard): Yes.
000:44:43 Scott (onboard): See that little - see that funny little switch they put on here?
000:44:46 Worden (onboard): Oh, really?
000:44:47 Scott (onboard): It came off.
000:44:48 Worden (onboard): How about [garble]...
000:44:49 Scott (onboard): Well...
000:44:50 Worden (onboard): I've got a pocket down here.
000:44:51 Scott (onboard): I got a pocket, no sweat, I just don't want to forget it and have it floating around.
000:44:54 Worden (onboard): Yes.
000:44:56 Irwin (onboard): Secondary Glycol Pump...
000:44:57 Worden (onboard): Okay. Optics eyepieces are in, G/N Optics Power going on. Optics Zero, Off, then Zero. Okay.
000:45:22 Worden (onboard): Okay, that's 15 seconds. The Optics Zero, Off - Mode, Manual. [Garble]. Here we go.
000:45:51 Worden (onboard): Hallelujah!
000:45:54 Scott (onboard): Getting stars?
000:45:55 Worden (onboard): Yes, sir!
000:45:56 Scott (onboard): Oh, okay.
000:45:59 Worden (onboard): Whoops. A good mark there.
000:46:06 Scott (onboard): Okay.
000:46:07 Worden (onboard): Who gave you permission to write [garble] out here? [Garble].
000:46:21 Worden (onboard): Okay. [Garble].
000:46:29 Scott (onboard): Yes. That's true. Oh, dear. [Garble].
000:46:35 Worden (onboard): Okay. Okay, old PICAPAR, let's see what you can do.
PICAPAR is a facility within the computer whereby it picks a pair of stars to be used for the realignment of the platform. Since the computer knows the attitude of the spacecraft and therefore where the optics are pointed, it can select a couple of stars within the field of view of the optics.
000:46:47 Worden (onboard): Okay; 33. Antares. [Garble]. Okay. And [garble].
000:47:01 Scott (onboard): [Garble].
000:47:10 Irwin (onboard): Boy, at night, you might - might as well be in the simulator [laughter].
000:47:14 Scott (onboard): Yes, except for the physiological change.
000:47:17 Irwin (onboard): Yes. Okay, the EPS monitoring check is complete, Dave.
000:47:25 Scott (onboard): Okay.
000:47:26 Irwin (onboard): Except for the battery relay bus read-out down there in Systems Test meter 5-B.
000:47:33 Worden (onboard): You can pick that up.
000:47:35 Scott (onboard): Yes.
000:47:40 Irwin (onboard): Yes.
000:47:45 Worden (onboard): Okay. It doesn't look too good [garble] down in there.
000:47:53 Irwin (onboard): EPS monitoring check now.
000:47:56 Scott (onboard): Okay. Did - did you do your fuel cell purge check, or [garble]...
000:47:59 Irwin (onboard): No, I couldn't do the H2.
000:48:01 Scott (onboard): Oh.
000:48:14 Worden (onboard): Double check [garble]. Forty-one. Okay, Dabih.
000:48:24 Scott (onboard): Forty-one, right.
000:48:45 Worden (onboard): [Garble]. Five in. [Garble].
000:48:56 Scott (onboard): Forty-one is what?
000:48:57 Worden (onboard): Dabih.
000:48:58 Scott (onboard): Dabih. [Garble] okay?
000:49:00 Worden (onboard): Yes. I got it.
000:49:03 Irwin (onboard): Okay, EPS monitoring check's complete.
000:49:11 Worden (onboard): Okay. Let's see how we did. [Cleared throat.]
000:49:15 Scott (onboard): Well, pretty good.
000:49:17 Worden (onboard): [Garble] all four [garble].
000:49:19 Irwin (onboard): About another 3 minutes for AOS,
000:49:23 Scott (onboard): Okay. I'll tell you what I'd like to do here [garble] the pass.
000:49:27 Worden (onboard): Do?
000:49:28 Scott (onboard): Check out the RCS real quick.
000:49:30 Worden (onboard): Here's the torquing angles, David.
000:49:32 Scott (onboard): Okay. [Garble].
000:49:33 Worden (onboard): Go back to zero, and I think I have to get the optics back out. Right? Did you stow the optics, Jim?
000:49:42 Scott (onboard): Okay. Here, do you want to torque at 40? What do we torque at rendezvous?
000:49:46 Worden (onboard): Yes, did - did you stow the optics eyepiece, Jim?
000:49:50 Scott (onboard): Should we torque about 50?
000:49:51 Worden (onboard): Yes.
000:49:52 Scott (onboard): Okay. Good deal.
000:49:53 Worden (onboard): Okay. You got the numbers written down?
000:49:55 Scott (onboard): Yes.
000:50:02 Worden (onboard): Very good, Dave.
000:50:03 Scott (onboard): Okay.
000:50:04 Worden (onboard): Very good [garble].
000:50:07 Scott (onboard): Okay, Al, and you might - Why don't you come up here and let me show you what the jets look like when we fire the [garble].
000:50:14 Worden (onboard): Oh, okay. Yes. Let me - let me check out a quick star here.
000:50:17 Scott (onboard): Well, we got to do - I want to do this before AOS.
000:50:23 Worden (onboard): Okay.
000:50:32 Worden (onboard): Well, let me climb up here. [Garble].
[Download MP3 audio file. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
This is Apollo Control; 50 minutes, 34 seconds Ground Elapsed Time in the mission of Apollo 15. Now approaching the Carnarvon, Australia tracking station. We're [going to have] about a 6½ minute pass over that station. [We are] halfway through the first Earth parking orbit. Next time they pass over Carnarvon or over [the] Australian subcontinent, the crew of Apollo 15 will be preparing for the Translunar Injection maneuver, [in] which the spacecraft and S-IVB stage will break out of Earth parking orbit and begin the 3-day journey to the Moon. Actually the targeting will be toward where the Moon will be three days from now. Still about 30 seconds away from predicted time of acquisition by the antenna at Carnarvon. We've had Acquisition Of Signal. Stand by.
000:50:34 Scott (onboard): Oh, I'm sorry. Okay. It's - it's good.
000:50:38 Worden (onboard): Yes. I [garble].
000:50:40 Scott (onboard): Yes.
000:50:45 Worden (onboard): Well...
000:50:51 Scott (onboard): Okay. You can probably look out my window.
000:50:54 Worden (onboard): Oh, yes. Very good...
000:50:56 Scott (onboard): I lost my watch.
000:50:57 Worden (onboard): Jim, you got my...
000:50:58 Irwin (onboard): Yes.
000:50:59 Worden (onboard): ...stopwatch?
000:51:00 Irwin (onboard): I'm looking for one.
000:51:05 Worden (onboard): Did you see that?
000:51:06 Irwin (onboard): Yes, I saw a flash.
000:51:07 Scott (onboard): Saw a flash? You did? Couldn't hear it - I didn't hear it. Huh, I'll be darned!
000:51:16 Worden (onboard): Could sure see a flash.
000:51:17 Scott (onboard): Yes. Saw a flash, but I didn't hear it. Gosh, I used to hear them all the time. Huh!
000:51:26 Worden (onboard): You know, it's amazing what [garble] outside that window [garble].
000:51:34 Irwin (onboard): Well, yes...
000:51:35 Scott (onboard): That's because you got your [garble] lights on in here.
000:51:37 Worden (onboard): Yes.
000:51:43 Scott (onboard): Okay, [garble] here.
000:51:47 Irwin (onboard): Okay, the secondary glycol loop check's complete.
000:51:50 Scott (onboard): Okay.
Communication is about to be handled through the Carnarvon tracking station in Australia. Apollo 15 still has just over one orbit of Earth to complete before Translunar Injection (TLI), the 5 minute, 50 second burn of the Saturn's S-IVB stage which takes them out of Earth orbit and on to the Moon.
000:51:56 Fullerton: Apollo 15, Houston through Carnarvon. Over.
000:52:00 Scott: Rog. Houston, 15. You're loud and clear.
000:52:03 Fullerton: You're loud and clear also.
000:52:06 Scott: Okay the insertion [and system] checks are coming along very nicely. We're down through [item] 21 in the checklist. And the cameras are out, and Al's completed his alignment.
Throughout the mission, one of Al Worden's jobs is to occasionally realign the guidance platform. He has just completed the first of 45 such realignments, a task usually known by the name of the program used, program number 52, or simply "P52".
Guidance and navigation are crucial to any journey and even more so in the ballistic dance of getting to the Moon and back. The crew must be able point the spacecraft to precise, well known directions, so that their engines will send them where they want to go. The spacecraft carries a gyroscopically stabilised platform within the IMU (Inertial Measurement Unit) which remains fixed in attitude while the spacecraft rotates around it, connected to it by three orthogonal gimbals. The only way to ensure that the platform is properly aligned is to compare it to a fixed attitude reference - the stars are almost always used. Initially, the CSM (Command/Service Module)'s platform was aligned before launch. Realignment is achieved by using P52 on the CMC (Command Module Computer). With the spacecraft held in a steady attitude the sextant is pointed at a specified star, marked, then to a second star, where another mark is taken. The computer, knowing the attitude of the spacecraft (relative to its own idea of where the stars are), now has new values of where the stars are located. The amount of drift the platform has experienced since the previous realignment is calculated, and displayed as the amount of correction needed to move, or "torque" the gimbals to bring the platform back into accurate alignment. Known as "gyro torquing angles", they are displayed on the DSKY as "Noun 93". These angles are usually very small, and are expressed in thousandths of a degree.
Scott, from the 1971 Technical debrief: "The post-insertion and systems configuration and checks went very smoothly. I don't think we had any problems at all. We took our time. We spent about 10 minutes or so just looking at the scenery after we cleaned everything up with the gimbal motors and all."
Worden, from the 1971 Technical debrief: "The guidance in the CMC was just dead-on, like what we looked at in simulation. I could almost repeat the numbers verbatim, because we had seen them so many times in simulation. It was just absolutely perfect, dead-on. The Z-torquing angle that we got after we got insertion was about half, as I recall, and that's just about what the first P52 showed, right in that ball park. We have the numbers written there somewhere [in their Flight Plan], but the guidance was right-on, super. We had no problems at all with the alignment. In fact, that was generally true with all the alignments. The first alignment went very smoothly. Tracking it in Orb Rate [the rate at which the vehicle was rotating as it orbited the Earth] was no problem. The Z-torquing angle came up about the same as they had called up."
Before Al began the platform realignment, the optics dust cover, on the opposite side of the CM from the hatch, was jettisoned to enable the spacecraft's optical instruments to be used. The cover protects the external surfaces of the sextant and scanning telescope during spacecraft preparation and launch. Al is to observe the jettison through the unity power SCT (Scanning Telescope).
Scott [to Worden], from the 1971 Technical debrief: "Optics cover jettison. Did you see any debris?"
Worden, from the 1971 Technical debrief: "Didn't see any debris. Didn't see anything through the optics when they went. All I heard was a slight thumping noise when the covers came off. That was it, never saw anything in the optics [relating to the jettison]."
000:52:21 Fullerton: Roger.
000:52:30 Scott: And I only got one comment [that] Jim's got for you.
000:52:32 Fullerton: Go ahead.
000:52:34 Irwin: Houston - Houston, 15. On the H2 purge, fuel cell 2, I cannot confirm [the H2 flow rate] since I had no - no read-out of a flow indication, or a caution and warning associated with that flow.
Jim Irwin is referring back to section 14 of the checklist which asks that the flow rate during the purge of the fuel cell by hydrogen gas be monitored.
The spacecraft's three fuel cells use the chemical reaction of hydrogen and oxygen, stored in cryogenic tanks, to produce the majority of electrical power for the CSM. The by-products from this chemistry are heat and water. The heat is discarded through eight radiators around the upper circumference of the Service Module. The water can be used for drinking or equipment cooling. Impurities in the reactants build up on the electrolyte and a purge is required at regular intervals to remove them and restore full capability. Purges with oxygen are carried out daily, but once every two days suffices for hydrogen purges. Controls on the right-hand side of the Main Display Console are provided for these functions.
000:52:50 Fullerton: Roger.
000:52:55 Irwin: And, if you'd like, I could do it any time, and perhaps you could confirm it.
000:53:06 Irwin: Houston, fif...
000:53:07 Fullerton: This is Houston. We're unable to help you on confirming that purge down here, Jim.
000:53:16 Irwin: Okay; understand. [Long pause.]
000:53:36 Worden: Gordo, this is Al. I've got the numbers on the P52 for you.
000:53:39 Fullerton: Okay. Ready to copy.
000:53:41 Worden: Okay. [I] used stars 33 and 41. Noun 05 was plus 000.01 and the torquing angles were minus 00.019, plus 00.021, minus 00.061, and they were torqued out at 50 minutes.
The Flight Plan requires that after each platform realignment, details of the task's result should be reported to Houston, either by voice or by calling up the angles on the DSKY display from where Houston can read them by telemetry. In this alignment, Al used Option 3 of P52, or the REFSMMAT (Reference to a Stable Member Matrix) option. This extraordinary acronym refers to the simple idea of a reference orientation which can be well defined and used by the crew in their platform alignments. The initial 5½ hours of the mission uses the precise orientation of the launch site at Kennedy Space Center at the time of launch as the reference to which the platform is aligned. As the flight progresses, other REFSMMAT alignments will be brought into play, eight in total, which include one based on the plane of the ecliptic, another based on the alignment of the landing site at the time of lunar landing, and others based on the computed alignment for major engine burns.
The realignment of the platform was generally done by sighting on stars, and computer carried a catalogue of the positions of 37 prominent stars distributed across the sky.
Scott, from 1998 correspondence: "But the crew had to know how to locate all 37 stars within the celestial sphere - one of the more interesting aspects of training. [We trained in] planetariums and [studied] the night sky while flying cross-country. The sky and its constellations became very familiar. Even though we did have a small diagram in the checklist, it was very important to be able to locate and positively identify each of the 37 stars. If the platform was too far from its desired orientation, the computer would not be able to point to the proper star."
The star maps from the G&C checklist are pages 6-8, 6-9 and 6-10.
The star reference numbers were given by their octal (base 8) number. The two stars used for Al Worden's first realignment were Antares (number 33) in the constellation Scorpius, and Dabih (number 41) in Capricornus. After the star sightings, the computer found that Al's measured angle between the stars, as given by Noun 05, differed from the angle the computer knows is between them, by only 0.01°. The difference between the intended platform orientation and its actual state was 0.019° in x, 0.021° in y, and 0.061° in z. These values were displayed through the Noun 93 display on the DSKY and were used to bring the platform back into correct alignment at 50 minutes into the flight.
The full list of stars, along with their reference numbers is as follows:-
The Apollo start list, with octal code numbers.
Note that four of these are not stars as such but allow the crew member to refer to other celestial objects to the computer.
000:54:07 Fullerton: Roger. Copied. And the torquing angles are minus 00.019, plus 00.021, and a minus 00.061. Over.
000:54:18 Worden: That's affirm.
000:54:20 Fullerton: Thank you.
Comm break.
This is Apollo Control. Cabin pressure aboard Apollo 15 [is] holding at 5.7 pounds per square inch [39.3 kPa]. Heart rates for Scott, Worden, and Irwin, respectively, are 70, 83 and 88.
000:55:39 Scott: And, Houston, one other comment. Apparently sometime during launch, the RCS-B secondary propellant isolation valve closed, and we recycled it and got a gray talkback.
000:55:52 Fullerton: Roger, Dave.
The "gray talkback" referred to by Dave Scott is an example of the indicators which were mounted around some of the instrument panels. Each talkback consisted of a small window with a black and white stripe pattern behind it - the "barber pole" often referred to during the mission. A gray flag could move in front of the barber pole stripes to indicate the status of a particular system. The gray flag would be driven by a control signal from the system in question and it told the crew what was going on in that system, therefore the indicator was called a talkback. Gray was essentially a normal or "doing nothing" indication. A barber pole in the talkback usually meant an abnormal or transient status.
Photograph of RCS talkbacks onboard Odyssey
The RCS talkbacks (bottom row) in the Apollo 13 Command Module, Odyssey.
This photograph, kindly supplied by Bruce Yarbro, shows the RCS talkbacks below the propellant switches in the Apollo 13 Command Module, Odyssey. The two talkbacks to the left are for the Command Module's RCS system, which will not be activated until re-entry. The four talkbacks to the right show half-barber pole in this photo and are the same as those in question.
For those who wonder at the term "barber pole", it comes from the red-and-white-striped pole that barbers display outside their establishments to make them identifiable to their clients. It harks back to a time when barbers indulged in dentistry and surgery. The photograph here is from a barber's shop in Maryhill Road, Glasgow.
Irwin, from the 1971 Technical debrief: "We had one secondary propulsion barber pole."
Scott, from the 1971 Technical debrief: "Yes, that's right."
Irwin, from the 1971 Technical debrief: "Insertion [means RCS-] B, B secondary, right?"
Scott, from the 1971 Technical debrief: "Yes, we sent that and it went great. ...[probably reading from notes] RCS-B secondary isolation valve barber pole, cycle to gray. It didn't come on at insertion. It came on at some other point."
Irwin, from the 1971 Technical debrief: "Yes, we noticed it when we did the check."
Scott, from the 1971 Technical debrief: "I made an SM [Service Module] RCS minimum impulse check, just to make sure that the RCS was working okay. I did that at 01:00 GET, and it worked fine. It was night and we could see the flashes. So I was fairly well convinced it was okay, that there wasn't any problem with it then. I don't remember what event would have triggered those barber poles unless somebody hit a switch, and nobody remembered hitting a switch. We talked about it, how did that thing get barber poled? When we noticed it, Al and I had been down in the LEB getting the helmet bags or something."
A recurring problem in the Apollo program was that the RCS propellant isolation valves [essentially, shut-off valves] occasionally closed during periods of heavy vibration or shock, rendering that particular RCS thruster unusable. Because the Service Module and Lunar Module used similar components, the valves in the RCS systems of both spacecraft could be affected by this. Indeed, one of the first post-landing steps for the Lunar Module was to cycle these valves to ensure they were open. Fortunately, this problem usually was regarded as a nuisance, since it was easily remedied. The postflight mission report concluded that variations in the supply voltage combined with the launch vibration was most likely to blame for closing these magnetic latching valves.
000:57:54 Worden (onboard): We should have Mag...
[Download MP3 audio file. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
000:57:55 Fullerton: Apollo 15, Houston. About 15 seconds to LOS. Estimating [contact with the] United States at 1:30 [GET].
000:58:06 Scott: Roger. 1:30.
000:58:09 Irwin (onboard): Al, my doggone checklist says Mag M ought to be on here for the UV.
000:58:14 Scott (onboard): Mag N?
000:58:15 Irwin (onboard): Mag M, man.
000:58:16 Worden (onboard): Yes, that's right...
000:58:17 Irwin (onboard): Yes...
000:58:18 Worden (onboard): That - that...
000:58:19 Irwin (onboard): ...
000:58:20 Worden (onboard): ...has the color stuff there, too.
000:58:21 Irwin (onboard): Oh.
000:58:22 Scott (onboard): ...take a picture ...
000:58:23 Irwin (onboard): Yes ... better get two of these...
000:58:26 Worden (onboard): Davy?
000:58:27 Scott (onboard): Yes.
000:58:28 Worden (onboard): You want to put that on there?
000:58:30 Scott (onboard): ...monitor?
000:58:31 Worden (onboard): Yes.
000:58:33 Scott (onboard): Yes. I don't know what we're going to do with this thing. I guess Jim has to hold this during TLI. Or something like that.
000:58:44 Irwin (onboard): Why - why can't I put it on the bracket?
000:58:47 Worden (onboard): You can.
000:58:48 Scott (onboard): ... Okay. Where's the bracket?
000:58:56 Worden (onboard): It's down in - A-1.
000:59:00 Scott (onboard): Okay.
000:59:03 Irwin (onboard): Bracket's in A-1.
000:59:04 Scott (onboard): Okay ... get it.
000:59:20 Worden (onboard): Man, that was some fantastic ride! Gaa!
000:59:26 Scott (onboard): Something you're not likely to forget for a while.
And we've had Loss Of Signal through the Carnarvon, Australia tracking station. We're standing by now for the post-launch press conference at press site 39 at Kennedy Space Center. And at 59 hours, 22 minutes [means 59 minutes, 22 seconds] Ground Elapsed Time; this is Apollo Control."
Flight Plan page 3-002
Acquisition of Signal (AOS) will be picked up 31 minutes later by the Goldstone station in California.
000:59:32 Irwin (onboard): And when you get a chance, Al, I need the - the UV bracket.
000:59:36 Worden (onboard): Okay.
000:59:46 Worden (onboard): The UV bracket, and the UV ..., and the UV lenses.
000:59:50 Irwin (onboard): Yes.
000:59:51 Worden (onboard): Yes.
000:59:54 Irwin (onboard): Am I supposed to be ... you, Al?
000:59:56 Worden (onboard): No.
000:59:57 Irwin (onboard): Okay.
Flight Plan page 3-2.
001:00:02 Worden (onboard): Here's the UV lenses.
001:00:18 Worden (onboard): Here's the UV bracket.
001:00:25 Scott (onboard): Camera checkout. Can I have the ... up here, Jim?
001:00:32 Irwin (onboard): Yes.
001:00:33 Scott (onboard): Yes.
001:00:34 Irwin (onboard): Okay, Al. Where'd it go? Let me trade you. Hold the lens for me. While you're holding the lens - If you'll hold that, I'll get you the bracket.
001:00:42 Worden (onboard): Okay. I'm holding it.
001:00:58 Worden (onboard): Okay ... UV bracket.
001:01:06 Irwin (onboard): Could you put this - here, I guess - can you put this lens away? Up there, or do you want me to keep it up here?
001:01:12 Worden (onboard): ... You'll - you'll need it if you take any color pictures ... lots of ... already. What's the matter, Davy?
001:01:30 Scott (onboard): (Laughter) You got to have the pyro arm circuit breakers in to turn the RCS command on.
001:01:36 Worden (onboard): How about that?
001:01:38 Irwin (onboard): We're going to keep you honest.
001:01:40 Worden (onboard): Okay, where do you want it?
001:01:41 Irwin (onboard): I'll take the...
001:01:42 Worden (onboard): Oh!
001:01:43 Irwin (onboard): I'll take the lens now.
001:01:44 Worden (onboard): Hmm. Okay...
001:01:53 Scott (onboard): ...
001:01:58 Worden (onboard): Okay, your pitch rate.
001:02:01 Scott (onboard): Why don't you...
001:02:03 Scott (onboard): Good ...
001:02:04 Worden (onboard): Okay, pitch?
001:02:05 Scott (onboard): Yes. Pitch, roll; roll, pitch. Good ...
001:02:11 Worden (onboard): Good.
001:02:14 Scott (onboard): And quad D going open.
001:02:21 Worden (onboard): ...
001:02:22 Irwin (onboard): Let me know when you all are...
001:02:24 Worden (onboard): ... in the way.
001:02:26 Irwin (onboard): ...ready for your TSBs, and I'll hand them to you.
001:02:28 Scott (onboard): Okay. Hey, you can give me mine, Jim. He's taking yours.
001:02:31 Irwin (onboard): Then when you get a change...
001:02:33 Scott (onboard): Okay, ... TV bracket.
001:02:34 Irwin (onboard): - - you can give it back.
001:02:51 Irwin (onboard): Okay, Al, here's your TSB.
001:02:53 Worden (onboard): Okay ....
001:02:56 Irwin (onboard): Dave, here's yours.
001:02:58 Scott (onboard): Gee, thanks a lot, Jim.
001:02:59 Irwin (onboard): Any time.
001:03:07 Scott (onboard): ... but the University of Michigan was well represented.
001:03:11 Irwin (onboard): Is that right? (Laughter)
001:03:14 Scott (onboard): Yes. Couple of little calling cards here.
001:03:16 Irwin (onboard): You know, I keep going up to the top of the vehicle.
001:03:18 Scott (onboard): Well, that's a common phenomenon.
001:03:20 Irwin (onboard): Up toward that hatch.
001:03:21 Scott (onboard): Everybody always has.
001:03:22 Worden (onboard): ... funny.
001:03:24 Scott (onboard): That's exactly right. We did that for 10 days and never figured out why.
001:03:38 Irwin (onboard): Shoot! ... somebody ... this hatch...
001:03:45 Scott (onboard): Al, I'm going to give you the ... to put back up there.
001:03:47 Worden (onboard): Okay.
001:03:48 Scott (onboard): So we don't lose track, here.
001:03:51 Worden (onboard): That's the name of the game for the next 12 days, gang. Put it back.
001:03:56 Scott (onboard): ...
001:04:14 Scott (onboard): Okay. Let's see, Al. Do you have the...
001:04:17 Worden (onboard): What? The TV lens? Where's the TV?
001:04:20 Scott (onboard): Right on the couch.
001:04:23 Worden (onboard): ... back here and see if I can bump into it.
001:04:26 Scott (onboard): Okay.
001:04:27 Irwin (onboard): Do you have the right settings on it? Want me to read them to you?
001:04:29 Worden (onboard): Yes, what are they?
001:04:34 Irwin (onboard): I don't know why we've been putting that TV up so early_
001:04:37 Worden (onboard): Just to get it out of the way.
001:04:46 Irwin (onboard): Okay. We want ALC to peak. And f/44.
001:04:55 Scott (onboard): Peak - and average.
001:05:02 Irwin (onboard): ALC to peak.
001:05:03 Worden (onboard): No, wait a minute; f/44.
001:05:l0 Scott (onboard): Okay, f/44.
001:05:12 Irwin (onboard): Yes.
001:05:30 Irwin (onboard): Guess we - we might as well leave the - the lens cover on until we're ready to use it.
001:05:35 Worden (onboard): Dave, did you do - do that SCS attitude reference - reference check?
001:05:38 Scott (onboard): I'm doing it right now.
001:05:39 Worden (onboard): Okay.
001:05:52 Irwin (onboard): Sunrise in about 16 minutes.
001:05:57 Scott (onboard): Okay, f-stop at 44, with about - ...
001:06:04 Worden (onboard): Get the - judge that...
001:06:07 Scott (onboard): Okay.
001:06:08 Worden (onboard): ...ground direction.
001:06:09 Scott (onboard): ... f-stop, 30, and the focus at - at infinity...
001:06:20 Worden (onboard): That's right.
001:06:21 Scott (onboard): I'll take those. I guess it doesn't really matter...
001:06:25 Worden (onboard): Yes.
001:06:26 Scott (onboard): Okay, Jim, if you want to stick that in the -
001:06:31 Worden (onboard): ... back you up.
001:06:35 Scott (onboard): And I'll plug it in.
001:06:56 Worden (onboard): Okay. Attitude reference check.
001:07:00 Scott (onboard): Okay.
001:07:15 Scott (onboard): Hey, Jim. You got the SPS monitoring check all right? ECS monitoring check? EPS?
001:07:23 Irwin (onboard): Yes. I've taken care of all those checks, Davy. [Garble] come up to the - docking probe.
001:07:35 Scott (onboard): Yes.
001:07:37 Irwin (onboard): After that SCS reference.
001:07:42 Scott (onboard): Okay, Jimmy, you're all hooked up.
001:07:44 Irwin (onboard): Okay. If I can just get my bracket in here. Pointed in the right dir...
001:07:49 Worden (onboard): Do we need anything else out of A-1, before I close it?
001:07:53 Irwin (onboard): When you get a chance, Al, out of R-12, I think I need that - probably need - [garble].
001:08:01 Worden (onboard): Just like that cardboard - for the window.
001:08:12 Scott (onboard): You - you want - you want to pull R-12 out?
001:08:15 Irwin (onboard): Yes, that whole brack - that temporary sto - that bracket? Yes. Yes, I think I'll probably stow the cardboard in there.
001:08:26 Worden (onboard): Okay. We really don't have a place to put this if you got the TV up [garble].
001:08:38 Scott (onboard): That's what you got a Flight Plan volume for.
001:09:07 Worden (onboard): Whoops.
001:10:03 Scott (onboard): How you doing, Jim?
001:10:06 Irwin (onboard): All right...
001:10:07 Worden (onboard): What do we have in there?
001:10:08 Scott (onboard): Flight Plan, Malfunctions, and all that jazz is in there.
001:10:11 Worden (onboard): Okay.
001:10:12 Irwin (onboard): The card - is my cardboard window shade in there, or something else?
001:10:15 Scott (onboard): We didn't find it here [garble].
001:10:18 Irwin (onboard): Thank you.
001:10:19 Scott (onboard): Probably [garble] supposed to be with the cue cards.
001:10:25 Worden (onboard): Okay, I didn't find it.
001:10:38 Scott (onboard): I don't know. Our Flight Data File boxes up here, they're almost empty.
001:10:44 Irwin (onboard): Maybe they just happened to fall open.
001:10:46 Scott (onboard): No, there's just very little in here.
001:10:47 Worden (onboard): That's all we need, is that Flight Plan. I talked to Ted Guillory [garble] all we really need. Up there is Volume I?
001:10:56 Scott (onboard): Yes. I've already [garble] all through these containers,
001:10:58 Worden (onboard): Oh.
001:10:59 Scott (onboard): Well, we got all our data - got all that...
001:11:03 Worden (onboard): It just doesn't take up a whole container. All those checklists ...
001:11:14 Irwin (onboard): [Garble]. There I need Mag N.
001:11:19 Worden (onboard): You need Mag N. (Cleared throat) Okay, coming up.
001:11:22 Scott (onboard): Where are the rest of the cue cards?
001:11:25 Worden (onboard): I think we got the [garble] in the pocket.
001:11:27 Scott (onboard): Do we?
001:11:28 Worden (onboard): Yes, I think so.
001:11:29 Scott (onboard): [Garble] reversed hoses here...
001:11:41 Irwin (onboard): [Garble].
001:11:51 Irwin (onboard): [Garble].
001:11:52 Worden (onboard): Nmm, ORDEAL.
001:11:54 Scott (onboard): ORDEAL?
001:11:56 Worden (onboard): Yes, man. [Garble] seems like it can be just a hell of a [garble].
001:11:59 Scott (onboard): Well, don't hurry.
001:12:00 Worden (onboard): Yes, let me - get my coffee here.
001:12:04 Scott (onboard): Yes.
001:12:10 Irwin (onboard): Did you finish that check, Dave?
001:12:14 Scott (onboard): Yes, the attitude reference check is complete.
001:12:22 Worden (onboard): Goddam [garble].
001:12:25 Scott (onboard): The what?
001:12:26 Worden (onboard): [Garble] the whole spacecraft.
001:12:41 Worden (onboard): Yes, the red one.
001:12:44 Scott (onboard): Here's Mag M, Jim.
001:12:48 Irwin (onboard): Okay [garble].
001:12:50 Worden (onboard): Okay, coming down to ORDEAL, David.
001:13:11 Worden (onboard): Oh! [Garble] can't - we can't do this - [garble] I can see [garble] hoses [garble].
001:13:15 Scott (onboard): Al, don't [garble]...
001:13:16 Worden (onboard): Okay, there we go, Dave.
001:13:17 Scott (onboard): No, that's all right.
001:13:18 Worden (onboard): I just got my hoses [garble] If you - if you can...
001:13:24 Scott (onboard): Yes, I can get it.
001:13:28 Worden (onboard): [Garble], Dave. There we go.
001:13:29 Scott (onboard): Good. We got it.
001:13:38 Scott (onboard): Okay. Got it?
001:13:40 Worden (onboard): Yes. Thank you.
001:13:55 Scott (onboard): Need some help?
001:13:58 Worden (onboard): Okay.
001:14:06 Worden (onboard): Well, this is going to be a backroom brawl.
001:14:09 Scott (onboard): What?
001:14:11 Worden (onboard): It's always your fault, Dave.
001:14:13 Scott (onboard): [Garble].
001:14:14 Worden (onboard): Got to be [garble].
001:14:17 Scott (onboard): But it's all of that?
001:14:24 Worden (onboard): [Garble] get myself hooked up on everything here.
001:14:32 Irwin (onboard): Hey, Al, if you get a chance on this - Did you find my cardboard window covering?
001:14:37 Worden (onboard): No.
001:14:39 Irwin (onboard): Data Card Kit?
001:14:41 Scott (onboard): Which part of the Data Card Kit?
001:14:43 Irwin (onboard): Well, I don't know. I don't know.
001:14:47 Worden (onboard): Here, let me look some more.
001:14:49 Scott (onboard): Yes. I don't even see where the cue-card part of the Data Card Kit is.
001:14:54 Worden (onboard): Uh-huh.
001:14:55 Scott (onboard): [Garble].
001:15:08 Worden (onboard): [Garble] Data Card Kit.
001:15:13 Scott (onboard): Okay [garble].
001:15:45 Worden (onboard): UV Card Book [garble].
001:15:49 Irwin (onboard): Okay. I guess I don't need it.
001:15:56 Worden (onboard): [Garble]. Okay.
001:16:06 Worden (onboard): Whoop!
001:16:12 Scott (onboard): Bet that ought to be [garble].
001:16:18 Scott (onboard): [Coughing.] Hey, you know, I got your meal, Al?
001:16:21 Worden (onboard): Do what?
001:16:24 Scott (onboard): [Garble] chow.
001:16:25 Worden (onboard): Oh, yes. Yes.
001:16:40 Irwin (onboard): Hey, I think I'm pretty well caught up with the UV photography here.
001:16:44 Scott (onboard): Good, Jim.
001:16:45 Irwin (onboard): Getting around with the...
001:16:47 Worden (onboard): Goody, goody. Read over the procedures.
001:16:51 Irwin (onboard): Want me to read them to you?
001:16:52 Worden (onboard): No, why don't you read them to yourself?
001:16:54 Irwin (onboard): Well, that's what I'm doing.
001:16:55 Worden (onboard): [Garble], Jim.
001:16:56 Scott (onboard): I - I - Did you get the - Oh, you're looking for the cue cards, is that right?
001:16:59 Worden (onboard): Yes, I'm just trying to get them all sorted out.
001:17:02 Irwin (onboard): And...
001:17:03 Worden (onboard): [Garble].
001:17:05 Irwin (onboard): Who has the tape?
001:17:07 Scott (onboard): Just a second, Jim, and I'll get it.
001:17:11 Worden (onboard): I can reach it. Have to push these back - Watch your foot!
001:17:17 Irwin (onboard): Oh!
001:17:18 Scott (onboard): [Laughter.]
001:17:19 Irwin (onboard): Man, you hit my foot; it really...
001:17:21 Scott (onboard): Did it really bug you?
001:17:22 Irwin (onboard): Yes.
001:17:35 Worden (onboard): I don't think we need the Data Card Kit out right now.
001:17:38 Irwin (onboard): May- maybe we could - Is there a good place to stow this down there?
001:17:40 Worden (onboard): Uh, I - I think you'd be better off if you stuck it right back in the window pouch, there.
001:17:45 Scott (onboard): Is this just for this pass, Jim?
001:17:46 Worden (onboard): Shade.
001:17:47 Scott (onboard): Yes.
001:17:48 Irwin (onboard): Uh...
001:17:49 Scott (onboard): Are you going to...
001:17:50 Irwin (onboard): Yes.
001:17:51 Scott (onboard): ...take it down?
001:17:52 Worden (onboard): I think - Yes, that's probably...
001:17:53 Scott (onboard): When?
001:17:54 Worden (onboard): ...that's probably true. The next pass is at about [garble].
001:17:59 Irwin (onboard): Yes, I'll have the cardboard up for it.
001:18:01 Worden (onboard): Yes.
001:18:02 Irwin (onboard): I need the - probably the [garble].
001:18:04 Worden (onboard): I guess we could put - we put that back up before we do TLI, don't we?
001:18:07 Scott (onboard): Yes.
001:18:09 Worden (onboard): You need what, Jim?
001:18:11 Irwin (onboard): Yes...
001:18:12 Scott (onboard): Oh, look at the horizon.
001:18:13 Worden (onboard): Okay, you guys, let that thing be - let it be.
001:18:15 Irwin (onboard): Oh, boy!
001:18:16 Scott (onboard): Come on up here and look at this. [Garble] switches.
001:18:22 Worden (onboard): Okay; all right. All right, have you got - have you got [garble] This is unreal to watch.
001:18:31 Scott (onboard): You've got to watch this, boy. This is one of the beauties that few people ever...
001:18:36 Worden (onboard): Ah!
001:18:37 Scott (onboard): ...get to see.
001:18:38 Irwin (onboard): [Garble]. Ooo!
001:18:39 Worden (onboard): Gaa.
001:18:40 Scott (onboard): [Garble]. Look at the clouds.
001:18:41 Irwin (onboard): Yes.
001:18:42 Scott (onboard): Just watch it, there. Watch this for a few minutes...
001:18:47 Worden (onboard): Look at that. You can see lightning. Looks like streaks of lightning around there?
001:18:54 Scott (onboard): See the little light thing out there?
001:18:57 Irwin (onboard): [Garble]. Oh, yes.
001:18:59 Scott (onboard): Oh, yes. I didn't see that.
001:19:00 Worden (onboard): I didn't either.
001:19:01 Irwin (onboard): [Garble].
001:19:04 Worden (onboard): Ooo, like - Oh, that - that's fantastic.
001:19:06 Scott/Irwin (onboard): That's a...
001:19:07 Worden (onboard): Yes.
001:19:08 Scott (onboard): That's a satellite.
001:19:09 Worden (onboard): Hey, you're right! That's got to be.
001:19:11 Scott (onboard): Yes.
001:19:13 Irwin (onboard): Sure it's a sat - satellite, not a - a planet?
001:19:16 Scott (onboard): That's a satellite, Jim.
001:19:18 Worden (onboard): Well, look.
001:19:20 Irwin (onboard): Come on. [Garble] planets are like...
001:19:21 Scott (onboard): Son of a gun.
001:19:22 Worden (onboard): I'm backwards.
001:19:25 Scott (onboard): Huh, I guess it is a planet. It's sure bright, though, isn't it?
001:19:28 Irwin (onboard): Yes [garble] rest.
001:19:32 Scott (onboard): It's sure bright, but it's a planet.
001:19:39 Worden (onboard): Is it going to be black like this all the way out?
001:19:46 Scott (onboard): Look at those clouds.
001:19:47 Irwin (onboard): Yes.
001:19:48 Worden (onboard): Yes...
001:19:50 Scott (onboard): I've got something like [garble].
001:19:54 Irwin (onboard): [Garble] see a damn thing.
001:19:55 Worden (onboard): [Garble].
001:19:56 Scott (onboard): No.
001:19:57 Worden (onboard): [Garble].
001:20:00 Scott (onboard): By golly, it's getting bright and early.
001:20:02 Irwin (onboard): I've got [garble] 8. [Garble] about like this.
001:20:14 Irwin (onboard): [Garble].
001:20:20 Worden (onboard): That Earth is a big mother.
001:20:23 Scott (onboard): Yes, it looks pretty big, but I think it's probably going to be small.
001:20:25 Irwin (onboard): [Laughter.]
001:20:26 Worden (onboard): Yes [laughter].
001:20:28 Scott (onboard): I hope it does.
001:20:30 Worden (onboard): [Cough] Yes, that must be a planet, Dave, because...
001:20:36 Scott (onboard): You were right.
001:20:37 Worden (onboard): ...it's staying in inertial, and we're going Orb Rate now.
001:20:42 Scott (onboard): [Garble].
001:20:44 Worden (onboard): [Garble].
001:20:47 Irwin (onboard): Boy! Get your sunglasses.
001:20:49 Scott (onboard): Yes, it's bright, isn't it?
001:20:50 Irwin (onboard): Boy, oh, boy!
001:20:55 Worden (onboard): Yes. [Garble]. Let's see, I'm going to start getting up around [garble].
001:21:10 Irwin (onboard): I don't think you can [garble].
001:21:11 Worden (onboard): I can. [Garble].
001:21:13 Irwin (onboard): I hear you. [Garble].
001:21:15 Worden (onboard): Too much trouble for me to get - for you to get [garble].
001:21:16 Scott (onboard): [Cleared throat.]
001:21:18 Worden (onboard): Looks like Aquarius coming up back there.
001:21:20 Scott (onboard): Yes. How about your rendezvous window, Jim?
001:21:24 Irwin (onboard): It's fine. Yes.
001:21:30 Scott (onboard): Okay. [Garble] load it with [garble].
001:21:37 Irwin (onboard): Yes.
001:21:40 Scott (onboard): [Garble]. You think you need a [garble] there, Jim?
001:21:42 Irwin (onboard): I've got it, man. It shouldn't.
001:21:43 Scott (onboard): I couldn't prove it to you.
001:21:47 Worden (onboard): [Garble] Oh, I see [garble].
001:21:51 Scott (onboard): Beautiful!
001:21:52 Worden (onboard): [Garble].
001:21:53 Scott (onboard): Check that.
001:21:54 Worden (onboard): [Garble].
001:21:55 Scott (onboard): I've got to get that [garble] to dock.
001:22:00 Worden (onboard): So you're going to [garble].
001:22:01 Scott (onboard): [Garble].
001:22:02 Worden (onboard): Which reminds me, I've got my own docking checklist.
001:22:05 Scott (onboard): Oh, you did?
001:22:06 Worden (onboard): Got your [garble]?
001:22:08 Scott (onboard): What's the matter with this other one?
001:22:10 Worden (onboard): Well, the one - the one I found, it's the one that doesn't have any, you know, any references in it.
001:22:15 Irwin/Scott (onboard): [Laughter.]
001:22:17 Scott (onboard): You never got the other one changed?
001:22:21 Worden (onboard): There ain't no way I could do that.
001:22:22 Scott (onboard): Okay.
001:22:25 Worden (onboard): [Garble] okay.
001:22:26 Scott (onboard): [Garble].
001:22:29 Worden (onboard): [Garble].
001:22:33 Scott (onboard): We'll be watching you.
001:22:34 Worden (onboard): Hand controller, not a [garble] control. Okay.
001:22:37 Scott (onboard): Okay. Why don't [garble] the program?
001:22:39 Irwin (onboard): [Cleared throat.]
001:22:40 Worden (onboard): ...
001:22:41 Scott (onboard): What do we have to do?
001:22:42 Irwin (onboard): Where are we stowing the tape?
001:22:43 Worden (onboard): Just ... it.
001:22:44 Scott (onboard): We should be stowing it back where it goes.
001:22:47 Irwin (onboard): Here's the tape, Al. Where are you putting it, down there ?
001:22:49 Worden (onboard): Okay...
001:22:57 Irwin (onboard): Well, we got 8 more minutes.
001:22:59 Worden (onboard): ...
001:23:00 Scott (onboard): Are you ready for the UV, Jim?
001:23:02 Irwin (onboard): Yes, ... It says 1:35.
001:23:05 Scott (onboard): Yes.
001:23:07 Irwin (onboard): I - I guess - I guess I might as well wait until then.
001:23:10 Scott (onboard): Yes, I think you should. Let's do everything right on the money.
001:23:14 Worden (onboard): The UV is on time ...
001:23:17 Irwin (onboard): Yes, sir.
001:23:18 Scott (onboard): When do we shut it off? Do you shut it off ...?
001:23:21 Worden (onboard): Yes. I agree with you.
001:23:22 Scott (onboard): I just want to...
001:23:23 Irwin (onboard): Do you want to wait until we get...
001:23:25 Scott (onboard): ...
001:23:27 Irwin (onboard): ...AOS before we do the docking probe, don't you?
001:23:29 Scott (onboard): Oh, I don't know.
001:23:30 Worden (onboard): (Cough)
001:23:31 Irwin (onboard): Do you want to go through it now?
001:23:33 Scott (onboard): Yes, let's go through it.
001:23:34 Irwin (onboard): Okay, CB Docking Probe, two, close. Two, verify.
001:23:36 Scott (onboard): Two, verify.
001:23:37 Irwin (onboard): Docking Probe Extend/Release to Extend/Release until full probe extension.
001:23:41 Scott (onboard): Okay, ready.
001:23:43 Worden (onboard): Okay, here it goes. You've got it, man.
001:23:46 Irwin (onboard): Yes.
001:23:47 Worden (onboard): Pretty good. Okay, got a barber pole to gray.
001:23:50 Irwin (onboard): Okay. Docking Probe Extend/Release to Retract. Talkback gray.
001:23:53 Worden (onboard): Retract. Talkback gray.
001:23:55 Irwin (onboard): Okay.
001:23:56 Scott (onboard): Okay, let's get ... here.
001:24:01 Irwin (onboard): There are a lot of clouds out there, huh?
001:24:03 Scott (onboard): Sure are...
001:24:18 Scott (onboard): Hey, Al, you got the - the Hasselblad down there?
001:24:21 Worden (onboard): Yes, it's in the TSB. The Hassel - Well, the Hasselblad's set up for the UV window.
001:24:25 Irwin (onboard): Yes.
001:24:26 Scott (onboard): The spotmeter. Did you get...?
001:24:27 Worden (onboard): Yes.
001:24:28 Irwin (onboard): Yes. Yes, it's...
001:24:29 Worden (onboard): Sure did.
001:24:30 Scott (onboard): The TV is all ready.
001:24:31 Irwin (onboard): Yes.
001:24:34 Worden (onboard): ...
001:24:37 Scott (onboard): ... the pad. You got your updates. Pyro Arm ...
001:24:45 Irwin (onboard): ...
001:24:47 Worden (onboard): ... the TLI Prep Book.
001:24:48 Irwin (onboard): Yes, ...
001:24:49 Scott (onboard): Hey, now, do you have the TLI card in your pocket?
001:24:52 Worden (onboard): No, I have it.
001:24:54 Irwin (onboard): No use in finding mine. I did look.
001:24:56 Scott (onboard): Okay.
001:24:59 Irwin (onboard): ...
001:25:01 Scott (onboard): It must be in my...
001:25:03 Worden (onboard): It must be in your...
001:25:05 Scott (onboard): Oh, yes? You get a better ... (laughter).
001:25:12 Worden (onboard): You carried my lunch; I carried your card.
001:25:16 Irwin (onboard): Did you really get it?
001:25:17 Worden (onboard): Sure.
001:25:20 Scott (onboard): ... S-IVB/TLI.
001:25:22 Irwin (onboard): ...
001:25:33 Worden (onboard): ...
001:25:34 Scott (onboard): Yes, I...
001:25:36 Worden (onboard): Well, I got a ... here ... a little culture.
001:25:48 Irwin (onboard): When we get past this cloud bank, I think I might take some of these UV pictures.
001:25:53 Worden (onboard): They want some clouds for the UV.
001:25:55 Irwin (onboard): Yes, I know. But I didn't want...
001:25:57 Worden (onboard): Oh.
001:25:58 Irwin (onboard): ...solid clouds.
001:25:59 Worden (onboard): What are you all looking at out there? Can you tell?
001:26:01 Scott (onboard): Oh.
001:26:03 Irwin (onboard): You mean what part of the world?
001:26:07 Worden (onboard): No - about where the camera's pointing .... They didn't care what time, but we need to correlate it ....
001:26:33 Worden (onboard): [Cleared throat.]
001:26:39 Irwin (onboard): ...
001:26:43 Worden (onboard): Hey, look. There's ... out there, I think.
001:26:44 Scott (onboard): Where?
001:26:45 Worden (onboard): Huh?
001:26:46 Scott (onboard): Yes.
001:26:47 Worden (onboard): ...
001:26:48 Scott (onboard): Yes.
001:26:49 Irwin (onboard): Oh, yes.
001:26:50 Scott (onboard): Hey, man.
001:26:51 Worden (onboard): Can you see ... over there?
001:26:52 Scott (onboard): Oh, that must be it.
001:26:53 Irwin (onboard): Yes.
001:26:54 Scott (onboard): Man. That must be it.
001:26:55 Worden (onboard): ...
001:26:56 Irwin (onboard): I'll take some UV pictures of it.
001:26:57 Worden (onboard): Okay.
001:26:58 Scott (onboard): That's good, Jim. Good deal.
001:26:59 Worden (onboard): Except I don't think we know the right time...
001:27:02 Scott (onboard): Yes.
001:27:03 Irwin (onboard): Oh, you can see some of that pattern...
001:27:06 Scott (onboard): ... far-reaching pattern.
001:27:08 Worden (onboard): Hey, yes. We know where it is.
001:27:15 Scott (onboard): ...
001:27:28 Worden (onboard): ... Is that the right thing?
001:27:40 Worden (onboard): This thing is really, really weird.
001:27:47 Irwin (onboard): ...I didn't even notice the S-IVB flashes, but you can see them now.
001:27:52 Scott (onboard): Yes. The S-IVB...
001:27:54 Worden (onboard): Yes, I noticed them. [Cleared throat.]
001:28:02 Scott (onboard): Well, let's see. I guess somebody's got to be ready to copy pads.
001:28:07 Worden (onboard): Yes.
001:28:08 Scott (onboard): Jim, I guess you're going to be busy with the...
001:28:11 Irwin (onboard): No, no, I'll be doing that. It won't take long to do this.
001:28:13 Scott (onboard): All right. I'll get the pyro arm check when we get the comm back.
001:28:19 Irwin (onboard): ...
001:28:22 Scott (onboard): Al, why don't you get the...?
001:28:24 Worden (onboard): Yes.
001:28:25 Scott (onboard): Why don't you get this thing...?
001:28:27 Worden (onboard): [Garble]?
001:28:28 Scott (onboard): [Garble].
001:28:29 Worden (onboard): Okay.
001:28:30 Scott (onboard): Okay.
001:28:31 Worden (onboard): Do you - do you want me to [garble] the [garble].
001:28:35 Scott (onboard): Yes. Yes, I've already scratched mine [garble].
001:28:50 Worden (onboard): Get the [garble] quantity...
001:28:54 Scott (onboard): The glycol pump? Get the glycol pump?
001:28:59 Worden (onboard): [Cleared throat.]
001:29:10 Fullerton: Apollo 15, Houston. Over.
001:29:12 Scott: Hello, Houston, 15.
001:29:15 Fullerton: Would you put the - You're loud and clear, Dave. Would you put the IU Uptel to Accept, please?
001:29:20 Scott: IU Uptel, Accept.
During the hour and a half since launch, tracking stations around the world have been refining the estimates of Apollo 15's position and velocity, collectively known as its state vector. The latest estimates are to be relayed to the guidance systems in the S-IVB's IU (Instrument Unit), and to the CMC (Command Module Computer). Ground controllers cannot update these computers at will, however. Two switches on the Main Display Console can enable either the IU or the CMC to accept data from the ground, or to block it. Section 29 of the Insertion and Systems Checklist calls for Mission Control to send a freshly calculated state vector to the IU once the crew has commanded the IU's computer to accept the data via uplinked telemetry (Uptel in short).
001:29:22 Fullerton: Okay; we're going to update the IU Nav vector based on tracking at Carnarvon. We'll have you leave that in Accept all the way through the [United] States pass. When we get a better track here across the States, we'll update it again - before the end. Over.
[Download MP3 audio file. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
This is Apollo Control. We join the conversation in progress with Apollo 15 through Goldstone.
001:29:38 Scott: Okay; will do. And we're down through 27 on the checklist. The docking probe is out. Looks good. And standing by for a sequence arm and a logic check when you're ready.
At the apex of the Command Module, a tripod shaped assembly, the docking probe, is extended out as a check of its operation and in preparation for docking operations to come. At the tip of the tripod, an articulated knob with three simple, sprung latches will make the initial contact with the LM's docking assembly, the concave, conical "drogue." The shape of the drogue guides the probe to a central hole where the latches engage to achieve "soft dock." If the probe had not extended, there could be no link-up with the LM and therefore no landing. In this circumstance it is perfectly feasible for the crew to continue to carry out a lunar orbit mission though whether Mission Control would have allowed it is speculation.
The crew's request for Mission Control to monitor their arming of the Sequential Events Control System (SECS) arm and logic check is at section 30 in the checklist.
001:29:53 Fullerton: Roger. We can do that now. [Pause.] Go ahead.
001:30:03 Scott: Okay. Logic one, On, now. Logic two, On, now. [Long pause.]
001:30:18 Fullerton: Logics are good. You're Go for pyro arm.
001:30:21 Scott: Okay; and we had one other little one [an anomaly]. At about an hour [GET], we noticed that the primary and secondary propellant isolation valves on Quad Delta were barber pole. We cycled the switch, and they are now gray. And the RCS checks okay.
This is a restatement of the RCS valve problem as discussed at 000:55:52.
001:30:38 Fullerton: Roger. [Pause.] I have a TLI plus 90 and lift-off plus 8 abort PADs, when you're ready.
Throughout the mission, large lists of numbers, called PADs, will be read up to the crew which give them the information necessary to carry out a particular maneuver. PAD stands for Pre-Advisory Data. Some of these "block data" are for planned maneuvers such as the TLI (Translunar Injection) or LOI (Lunar Orbit Insertion) burns. Other PADs, such as the "TLI plus 90" and "Lift-off plus 8" mentioned here are the first of 27 abort options which will be read up to the crew at scheduled times throughout the early and middle portions of the mission. Note that the TLI+90 PAD has nothing to do with TLI itself but would occur 90 minutes after a successful TLI burn in the event of an abort. However, mission planners have decided that at no time beyond Earth orbit will the crew be without a get-us-home PAD. Then, any time they might lose communication with Earth, they will have the information to hand to get themselves back manually.
To simplify the voice transmission of these huge lists of numbers and reduce the likelihood of errors, each type of PAD was precisely formatted both in Mission Control's and the crew's paperwork - all the crew needed to do was fill in the blanks.
Scott, from 1998 correspondence: "Another example of precision planning (a major key to Apollo success)."
The abort PADs are the responsibility of RETRO, one of the flight controllers in the front row of the MOCR (Mission Operations Control Room). Chuck Deiterich was one of those who occupied the RETRO console throughout Apollo.
Chuck Deiterich, from 2003 correspondence: "There is quite a bit of protocol in the PAD process. Empty PADs were in tablets of no carbon required (NCR) paper. We would make about 6 copies and use a red ballpoint on the top (original) so the CapCom would be sure what was part of the printed form and what was data."
Chuck supplied a sample PAD form from the Apollo 8 mission.
Apollo TEI PAD as generated by Chuck Deiterich for Apollo 8.
Apollo Trans-Earth Injection PAD as generated by Chuck Deiterich for Apollo 8.
Deiterich, from 2003 correspondence: "You can see where the CapCom checked each item during the crew readback. A printed X on the PAD said no data goes here, a printed 0 indicated the computer would always have a zero here (ignition time for example), a heavy box on a square indicated a + or - sign should go here (sometimes a letter like D.) Only the red data was read up, thus saving comm time."
Page 2-15 of the Flight Plan includes a schedule of all the "Return to Earth Block Data" PADs. Three basic types of abort PAD are shown; "Complete P30" which defines all the parameters for a return to Earth, "P37" short versions which give data for the computer's P37 Return to Earth program, and the "Abbreviated P30" which assumes some data already has already been given in a full P30 abort PAD. The intention of these PADs is to ensure that at all stages of the flight, the crew have the information to hand with which they can get themselves on a homeward trajectory, in the event that they permanently lose communication with Earth.
001:30:52 Scott: Can you stand by one, please, Gordo?
001:30:54 Fullerton: Okay.
001:30:56 Scott: Getting a little UV here. [Pause.]
Even at this early stage of the mission, and despite the huge workload, the crew have begun to fulfil their science objectives by taking a sequence of photographs of Earth using ultra-violet (UV) sensitive film, on magazine N. From the point of view of the couches, looking towards the apex of the CM, the extreme right-hand window, no. 5, has quartz panes fitted for high UV transmission rather than the coated tempered glass used in the other windows. A Hasselblad camera, fitted with a 105-mm f/4.3 Zeiss Sonnar UV transmitting lens, is used with four filters, each with a different spectral response, one being in the visual range. The CSM launch checklist, at page 2-19, describes the procedure for this particular sequence of photographs. Two images are taken at 1/60th of a second exposure with filter 1. With the camera's shutter set to B (time exposure), two more are taken through filter 2 with 20 second exposures. Filter 3's pair of exposures are at 1/250th while filter 4's are at 1/500th of a second. The eight photographs are AS15-99-13402 to 13409. AS15-99-13408 is an example of one of the exposures through filter 4. Although the checklist called for an additional photograph to be taken through the same window/lens combination on conventional colour daylight film, the crew have decided that, because of the pressure of time, they would delete this item.
Irwin, from the 1971 Technical debrief: "I don't know that we had a color mag[azine] out at that time. I think we just had a UV mag out."
Worden, from the 1971 Technical debrief: "I recall now, we did discuss that in-flight. I think we decided that the color mag would be nice if we could get the same area that we had taken the UV pictures of. But we couldn't do that because of the time. It wasn't valuable taking a color [picture] of some spot other than where we had taken the UV."
By the time their orbit brings them back over the spot where they took the UV pictures, they will be occupied with preparations for TLI. After the UV sequence is finished, the camera is configured with the 80-mm lens and colour film in preparation for photography of the T, D & E (Transposition, Docking and Extraction) maneuver after TLI.
001:31:06 Irwin: Okay, Gordo. I'm ready for the TLI [means TLI plus 90] PAD.
When all three crewmen are occupying the Command Module, it is usually Jim Irwin who takes the task of being the secretary and writing down the data read up from Earth.
001:31:09 Fullerton: Okay. This is the TLI plus 90 abort PAD, Jim.
001:31:14 Irwin: Okay.
001:31:16 Fullerton: TLI plus 90, SPS/G&N; Noun 47 is 66938; minus 0.52, plus 1.90; GET for ignition is 004:19:56.99; Noun 81, minus 0425.4, plus 0000.1, plus 4921.7; attitude, 180, 166, 002; HA is N/A [not applicable], HP, plus 0021.0; 4940.1, 6:34, 4920.8. Sextant star is 40, 079.5, 35.9; boresight star, N/A; Noun 61, plus 16.04, minus 030.00; 1099.0, 34492; GET for 05g, 017:43:58; GDC Align stars are Deneb and Vega; 112, 128, 356; no ullage. Go ahead. [Long pause.]
As Fullerton read the PAD, a complete P30 type, the Lunar Module Pilot, Jim Irwin, copied the values to the appropriate form in the checklist. An example of the form is on page 5-11 of the CSM Launch Checklist.
Interpretation of this particular PAD is as follows: Delta-VC requires a little more depth of explanation. SPS engine burns are normally controlled by the G&N system. If it is a long burn, that is, greater than six seconds, the control is closed loop. The system monitors the achieved Delta-V and shuts down the engine at the appropriate time to reach the required Delta-V. In doing so, it takes account of the engine's tail-off impulse, which is the amount of thrust that the engine continues to impart after the shutdown command. It knows the thrust that is expected from this tail-off and can calculate the resulting tail-off Delta-V based on this and the spacecraft mass.
If the G&N system were to fail during a burn, the EMS provides a backup means of shutting down the engine at the right time. This equipment carries a separate accelerometer which measures Delta-V along the longitudinal axis of the spacecraft. Prior to the burn, the crew enter the expected Delta-V into a display on the EMS. As the burn progresses, the figure showing the remaining Delta-V drops towards zero, at which time the EMS sends a shutdown command to the SPS in case the G&N system has not already done so. However, the EMS has no knowledge of the tail-off thrust. The flight controllers take this into account and give the crew a low Delta-V figure for entering into the EMS so that if it is called upon to shut down the engine, it will do so early enough for the tail-off thrust to effect the correct total Delta-V.
Continuing with the explanation of the PAD: The next five parameters all relate to re-entry, during which an important milestone is "Entry Interface," defined as being 400,000 feet (121.92 km) altitude. However, in this context, a more important milestone is when atmospheric drag on the spacecraft imparts a deceleration of 0.05g. GDC Align is another term that needs a little more explanation. The spacecraft has two independent systems for determining attitude and changes in attitude. The primary system is the IMU and its stable platform, held orientated to the stars by gyroscopes. A secondary system, usually tied to the SCS, comprises a set of gyros that are attached to the spacecraft structure. In other words, being mounted directly to the body of the spacecraft, their mounts are not stable. Unlike the IMU, which measures absolute attitude, these gyro assemblies only measure the rate of attitude change. However, absolute attitude can be derived from these measurements by integrating the change, a job carried out by the GDCs (Gyro Display Couplers). This technique is imprecise so at regular times, the crew presses the GDC Align button to make the GDCs knowledge of attitude match the IMU's. The question then arises; what happens if the IMU is not working? The crew then have a backup method of aligning the GDCs by sighting two stars through the scanning telescope in a particular way. They know what the spacecraft's attitude should be when this is achieved and can dial this into the GDCs, properly aligning them.
The final note in the PAD concerned the ullage burn. Since the SPS propellant tanks are full, there is no need to perform a small RCS burn, known as the ullage burn, to settle their contents.
As CapCom Gordon Fullerton was reading up the PAD, the communication route was transferred to a ship in the Atlantic, USNS Vanguard. The changeover has caused Jim to miss some of the information. Journal Contributor Brian Lawrence adds, "I'm guessing that USNS means US Navy Ship? I DO know that it means that it's a ship crewed by civilians - where USS is a Navy-crewed vessel."
001:34:15 Fullerton: 15, Houston. [No answer.]
001:34:29 Fullerton: Apollo 15, Houston. Over. [No answer.]
001:34:46 Fullerton: Apollo 15, Houston. We're not reading you. Over.
001:34:50 Worden: Okay, Houston; there is a breakup - breakup in the VHF, and Jim lost some of the first part of the transmission. Could you go through it again?
001:34:58 Fullerton: Okay, just what do you need?
001:35:00 Irwin: We have Noun 47 through roll, pitch and yaw.
001:35:04 Fullerton: Okay, Jim. Noun 47 is 66938; minus 0.52, plus 1.90; Noun 33, 004:19:56.99; Noun 81, minus 0425.4, plus 0000.1, minus 4921.7 - correction on Delta-VZ is a plus 4921.7; roll, pitch, and yaw are 180, 166, 002. Go ahead.
001:36:10 Irwin: Okay; readback: TLI plus 90, SPS/G&N; 66938; minus 0.52, plus 1.90; 004:19:56.99; minus 0425.4, plus 0000.1, plus 4921.7; 180, 166, 002; N/A, plus 0021.0; 4940.1, 6:34, 4920.8; 40, 079.5, 35.9; N/A, plus 16.04, minus 030.00; 1099.0, 34492; 017:43:58, Deneb and Vega; 112, 128, 356, and no ullage.
001:37:13 Fullerton: Okay, Jim, your readback's correct. Lift-off plus 8 PAD is 008:00, 6076, minus 175, 027:06. Go ahead.
001:37:38 Irwin: Roger. 008:00, 6076, minus 175, and 027:06.
The Lift-off + 8 PAD carries data for P37, a program in the computer that will calculate the details of a burn that will return the crew to Earth. An important condition for P37 is that the spacecraft must still be in Earth's sphere of influence, thus simplifying the calculations. The program takes the four values from the PAD; the specified time for ignition of the engine, a specified maximum change in velocity (or Delta-V), the longitude of the splashdown and the GET for the start of re-entry. These act as a set of constraints with which it calculates the desired trajectory and the details of the burn to achieve it. The CSM G&C Checklist provides spaces for the P37 data on pages 4-23 and 4-24.
001:37:51 Fullerton: Roger. And I'll have the TLI PAD when you're ready for that one. [Pause.]
001:38:03 Irwin: All right. Go ahead. I'm ready for the TLI PAD.
001:38:07 Fullerton: Okay. Time base 6 predict 2:40:23; attitude for TLI, 180, 045, 001; burn time 5:55; 10401.1, 35599; Sep attitude, 359, 077, 320; extraction attitude, 301, 257, 040. R2 align, 045.0, 038.0; ORDEAL start, 56:45; Yaw 001; ejection time 4:16:00. Go ahead.
The data read up by Fullerton is structurally different to other PADs as the maneuver is controlled by the IU on the launch vehicle, and not the computer in the CM. A form for filling in the numbers is available on page 2-21 of the launch checklist.
The timings for events relating to the launch vehicle are defined relative to a number of time bases, each of which start with a particular event. This allows complete sequences of events to occur relative to indeterminate points of the flight rather than to the overall mission time. The restart sequence for the S-IVB's single J-2 engine is tied to time base 6, itself determined by tracking of the stack's orbit. When TB-6 begins, all subsequent events to restart the engine such as tank repressurisation, engine chilldown, ullage, etc., follow on, leading to the engine start command 9 minutes, 30 seconds later, and ignition 8 seconds after that.
The crew also has tasks to perform in the minutes leading up to the TLI burn and they use their event timer to help them. Around 002:40:23, TB-6 begins and this is shown by both the 'Uplink Activity' and 'S-II Sep' lamps coming on. The former is illuminated for ten seconds, the latter for 38 seconds. At 9 minutes to ignition, the point at which the 'S-II Sep' lamp is extinguished, Dave will start the event timer counting up, having previously set it to 51:00. This will give a visual count-up to and beyond ignition to aid the crew in sequencing their final tasks before and during TLI. Items in the checklist are therefore shown with times from 51:00, through (1:)00:00 and upwards.
The PAD is interpreted as follows: The term 'orbital rate' refers to a how a spacecraft is orientated in orbit. If a spacecraft is in orbit with a fixed attitude relative to the celestial sphere (i.e. the spacecraft keeps pointing to the same stars no matter where it is in its orbit), then its attitude relative to the body it is orbiting (Earth, Moon or whatever) is constantly changing. For example, at one point in its orbit, the front of a spacecraft can be pointing directly at the planet below. Half an orbit later, it will be pointing directly away. This is known as "stellar inertial."
Diagram explaining difference between orb-rate and stellar inertial attitude
Diagram explaining difference between orb-rate and stellar inertial attitude.
Conversely, if the spacecraft is to be flown in 'orb-rate,' keeping the same face towards the surface (to point cameras for example), it must rotate around one of its axes, usually the pitch axis, at a rate which matches the orbital period. Normally, the FDAI displays the spacecraft's attitude relative to the celestial sphere (i.e. it normally shows the inertial attitude) but the function of the ORDEAL is to provide the correct drive signal to rotate the FDAI at a rate which also matches the orbital period. With the ORDEAL, the FDAI can be made to display attitudes relative to the surface below.
During Apollo 15's TLI, the crew are going to use the ORDEAL to drive the FDAI at a rate which matches the pitch rate of the S-IVB during its powered flight. This way, the crew can monitor the progress of the TLI as far as the vehicle's attitude is concerned, and they can take over manual attitude control if required during the burn. They must start the ORDEAL working at a precise time if the FDAI is to show zero attitude errors, otherwise the spacecraft's further motion around Earth will cause it to be offset one way or the other.
001:39:35 Irwin: Roger. TLI readback: 2:40:23; 180, 045, 001; 5:55; 10401.1, 35599; 359, 077, 320; 301, 257, 040; 045.0 [garble] 56:45; 001; and extraction at 4:16:00.
001:40:15 Fullerton: Okay. A little static on two readbacks. Read back Yaw for extraction and R2 align, please?
001:40:24 Irwin: Roger. 040 and 045.0.
001:40:29 Fullerton: Okay. Readback's correct, Jim. [Long pause.]
Within their high-tech environment, it may seem somewhat strange for the crew to be given large quantities of mostly numerical information in such a low-tech fashion. At first glance it may appear easier to simply have the data uplinked to them and stored in the computer. However, the computer was not designed as a repository of data in the sense that we have come to think of computers thirty years after Apollo. It functions more like a real-time controller, albeit a very sophisticated one, and not completely unlike the embedded controller chips found in a VCR or microwave oven. The abort PADs are, in essence, a 'checklist' of items that the crew have to sequence through (Program 30 can be quite long), and although there are minimum keystroke ("minkey") options, there was never a 'scripting capability' that would automatically execute a program using stored responses. Additionally, there are verbal comments included in the PADs which cannot be entered into the computer.
In light of later, post-Apollo computer systems, it was an incredible feat to get the programming into the CM computer's 32Kwords of storage; most of this being hardwired into rope core memory. There was only 2Kwords (4K bytes) of erasable storage in the machine, and this was used to the maximum. During the Apollo 11 landings, using the very similar LM computer, the resource that the 1201/1202 alarms were complaining about was the lack of erasable memory.
The crucial importance of the data requires that the crew write it down and have 'hard-copy' available to them in case of the very systems failure that might invoke such an abort. Say, for instance, that the guidance computer fails. Having the abort PADs stored electronically would make them inaccessible. Or, say an oxygen tank blows on the way to the Moon, and you have to power down the entire Command Module, computer and all à la Apollo 13. It's tough to beat having a piece of paper with all the vital information for getting home written on it.
It's important to realize that although the computer is a critical part of the spacecraft, it isn't an absolute requirement for its operation. Early in the development of the computer, there were even serious doubts that it would remain functional for the entire mission! As a result, Apollo was designed to be flown without an operational computer. All the tasks that it normally manages could be done manually. (Making attitude adjustments, firing the engine, etc.) An essential design philosophy: Always try to have survivable options even when a critical piece of equipment fails.
Scott, from 1998 correspondence: "The design philosophy was even more precise than 'survivable' options - survivable' being exactly what? The back-up system was usually of a completely different design, never two - prime and backup - of the same 'kind.' This was one of the major factors in 'What Made Apollo a Success?' Operating, maintaining, and learning two completely different systems for one purpose was far more difficult and costly than having two identical systems for redundancy - but the concept proved its worth, time and again."
001:41:00 Fullerton: 15, Houston. We have a question regarding the primary and secondary isolation valve. Over.
001:41:07 Scott: Go ahead.
001:41:08 Fullerton: We're wondering if you happened to just notice them [as] barber pole at one hour [GET], or did you notice them close at one hour? Over.
Although the RCS isolation valve problem was a previously known occurrence, Mission Control would like to understand it better, in case they are facing a new problem.
001:41:16 Scott: Ah, no. We just noticed that they were closed at an hour, But apparently in the shuffle here, somebody probably bumped the one switch which would do it.
001:41:26 Fullerton: Roger. You don't - you can't tie them to any other action or event there then? Is that right?
001:41:32 Scott: Negative.
001:41:33 Fullerton: Okay; thank you.
001:41:35 Scott: Okay.
Comm break.
001:42:58 Fullerton: 15, Houston. [Could you put] IU Uptel to Block? We have put in a second IU Nav[igation] vector, based on Stateside data.
Like the computer in the Command Module, the computer in the IU can either accept data from the ground (via uptelemetry) or that data can be blocked, depending on a switch on Panel 2. The IU now has a more accurate knowledge of the vehicle's trajectory.
001:43:08 Irwin: Uptel to Block. [Long pause.]
001:43:26 Fullerton: 15, Houston. We'd like P00 and Accept.
001:43:31 Scott: P00 and Accept. You've got it.
Comm break.
Now the Command Module's computer, the CMC, is set to receive the updated state vector. The CMC must be in an idle status (running P00, essentially a "do-nothing" program) with switches set to accept ground updates. P00 is commonly pronounced "pooh" by all the Apollo crews as in the character from A. A. Milne's book "Winnie the Pooh. As recounted in Murray & Cox's book, Apollo: The Race to the Moon, this program name even entered the daily lingo of the flight controllers. To 'go to poo' meant to go to sleep."
As an aside, the CMC has 39 programs available to the crew. Numbered in octal (base eight), they are arranged into categories depending on their function. Note that not all available numbers within these groups are used.
001:45:21 Fullerton: 15, Houston. IU Uptel [means CM Uptel] to Block. You have a new state vector now.
001:45:27 Scott: Roger. CM Uptel going to Block.
001:45:31 Fullerton: Roger. My mistake. Also have a short update for your TLI checklist ORDEAL angles because of the slight performance difference in the S-IVB. Over.
001:45:49 Scott: Okay; go ahead, Gordo.
001:45:51 Fullerton: Okay. On the launch checklist, page L2-30, bottom of the page. Tell me when you have it. [Pause.]
001:46:04 Scott: Go ahead, Gordo.
001:46:06 Fullerton: At 56 minutes, slew FDAI number 1 to pitch equals 17 degrees rather than 16; and, at the top of the next page, ensure FDAI number 1 pitch equal 14 degrees rather than 13. Over.
001:46:24 Scott: Roger. Copied. 17 degrees instead of 16, and 14 instead of the 13.
001:46:36 Fullerton: Okay; then on the next page, 2-32 at 59:55, change 7 degrees to 8 degrees, ensure FDAI number 1 pitch equal 8 degrees.
001:46:49 Scott: Copy, 8 degrees.
001:46:50 Fullerton: One more on the cue card for TLI down slightly below the middle, the long cue card that the CDR uses at 54 minutes. The 24 degrees should be changed to 25 degrees. "Ordeal 300/Lunar, 25 degrees.
001:47:09 Scott: Okay, we've got that; 25 degrees.
001:47:15 Fullerton: And then there will be a 1 degree difference on the rest of the ORDEAL numbers.
001:47:19 Scott: Okay; looks like they all fit.
001:47:22 Fullerton: That's it.
Comm break.
001:48:46 Fullerton: Apollo 15, Houston. We're about to LOS. Nothing further. We'll see you at Carnarvon at 2:25 GET.
001:48:53 Scott: Ah, Roger. 2:25...
Very long comm break.
This is Apollo Control. Apparently, we have had Loss Of Signal through the Vanguard tracking ship in mid-Atlantic. During that pass over the United States, the numbers for the upcoming Translunar Injection maneuver was passed up - were passed up to the crew. This maneuver, slightly over an hour from now, [is] planned at 2 hours, 50 minutes Ground Elapsed Time. The burn, lasting 5 minutes, 55 seconds with the S-IVB third stage, will place the spacecraft into a trajectory toward the Moon. It will increase the velocity by some 10,414 feet per second (actually 10,401.1 fps [3,170.3 m/s]). The measurement of the Apollo 15 Earth orbit as it passed over the Texas Tracking Station; the display here in Mission Control showed the present orbit at 96.5 by 93.8 [nautical miles, 178.7 by 173.7 km]. During the launch phase, the heart rates of the crew of Apollo 15 were 110 for Scott, 104 for Worden and 115 for Irwin. We'll be communicating with the crew of Apollo 15 through the Carnarvon Station at Ground Elapsed Time of 2 hours, 24 minutes and some odd seconds and almost continuous communications through ARIA or Apollo Range Instrumented [means Instrumentation] Aircraft between Carnarvon and the Hawaii Tracking Station. The TLI burn begins just about the commencement of the pass over Hawaii. And at 1 hour, 51 minutes Ground Elapsed Time, this is Apollo Control.
Flight Plan page 3-005.
The crew has moved on the "TLI Preparation" section of the launch checklist on page 2-29. They have settled into weightlessness easily and are not reporting any of the adaptation problems which other crews have experienced.
Scott, from the 1971 Technical debrief: "I had fullness of head as I expected to have. I had no other sensation whatsoever. On Apollo 9, I had felt some tendency not to want to move my head, but in this case I felt completely at ease. I noticed in looking around, that I felt quite well adapted immediately upon getting into orbit. I think that probably had to do with all the flying we did prior to the flight, the acrobatics and everything in the T-38. That's the one thing that I did different from Apollo 9. I really believe that was a help, because that was the only thing that was different. I felt much better this time than I had on Apollo 9."
Dave was CMP on Apollo 9 when Rusty Schweickart became sick. After this (and Frank Borman's similar illness during the Apollo 8 mission) crews began flying vigorous aerobatics in the T-38 jet aircraft they had available to them. Mike Collins discusses this attempt at inner-ear conditioning in Carrying the Fire. "The idea of the T-38 was not so much to fly weightless parabolas, but rather to perform a variety of violent aerobatic maneuvers, loops and rolls, to slosh that fluid (in the inner-ear canals) around, in poor but hopefully adequate imitation of the sloshing motion induced by moving around the Apollo cabin in weightlessness."
Journal contributor David Harland adds that the Russians report that having been up once makes the second flight a piece of cake, as if the body remembers how to cope with the weightless conditions. Also, although Dave flew with Neil Armstrong on Gemini VIII prior to the Apollo flight, they were strapped inside a very cramped spacecraft on a flight that was aborted early. Nausea induced by weightlessness only became a problem when crews experienced the freedom of movement permitted by the relatively roomy Apollo CM.
Worden, from the 1971 Technical debrief: "I had the same thing, a little fullness in the head. But I never at any time noticed any problems with equilibrium, sensation of spinning, or any problems with moving my head. The thought crossed my mind at the time that it was probably a result of zero-g flight. I was ready to move right away, get down in the LEB [Lower Equipment Bay] and get on with that part of it, Dave kept telling me to slow down a little bit. I think we both came to the conclusion that there wasn't really any reaction. We weren't getting any reaction out of it. We could proceed on normally after a few minutes."
Scott, from the 1971 Technical debrief: "Yes, that's right. How did you feel, Jim?"
Irwin, from the 1971 Technical debrief: "Well, I definitely had a fullness of head that persisted for 3 days. I had just a slight amount of vertigo. I didn't want to move my head very fast or move very fast in any direction. That was more pronounced, of course, once we got inserted [into Earth orbit]. That feeling gradually subsided, but I still had a slight amount of vertigo, even after 3 days."
Worden, from the 1971 Technical debrief: "I really felt like we were right at home when we got into orbit. I really felt very comfortable in the environment. Maybe that's part of it too. If you feel comfortable with that kind of environment, that may help you adapt more to it."
Irwin, from the 1971 Technical debrief: "I just didn't want to move very fast, but [I was] not nauseous."
Scott, from the 1971 Technical debrief: "That's the way I felt on Apollo 9. I just didn't want to go fast. It might just be the time of year, as far as anybody knows. But there were no problems. As far as any other anomalies, I can't think of anything else prior to TLI. We were well ahead of the checklist all the way. We had plenty of time to look out the window and watch the scenery. We took in a couple of looks at the sunrise and the Earth airglow and everything. I think the time line was well organized."
Worden, from the 1971 Technical debrief: "As a matter of fact, I thought we had a lot more time in flight to just look out the windows, see the Earth and see what was going on, etc., than we ever had in simulation. The time line seemed to work out so much better, for some reason, that we really had additional time, and it just flowed so smoothly that we didn't miss anything in the checklist."
001:53:35 Irwin (onboard): ...[garble], Inject.
001:53:36 Scott (onboard): Inject.
001:53:37 Irwin (onboard): EDS Power, On, up.
001:53:42 Scott (onboard): Okay. Well, I checked the Delta-V on the EMS; and, I guess, you might as well just hold on until we get all the way around here - until we get the ... again. There's nothing else really to do.
001:53:57 Irwin (onboard): Okay. You got EDS Power, On, up?
001:53:58 Scott (onboard): No, hold...
001:53:59 Irwin (onboard): You want me to hold off?
001:54:00 Scott (onboard): Yes.
001:54:01 Irwin (onboard): Okay...
001:54:02 Scott (onboard): Really not much more to check. GDC align; I'll wait until we get a little bit farther down the road to do that.
001:54:10 Irwin (onboard): Okay. Where is my kitchen timer, Al?
001:54:13 Worden (onboard): Down below. You want it?
001:54:15 Irwin (onboard): Yes, I guess I ought to put it to use when I start cycling on the cryo fans here shortly. You know, we - actually, we have plenty of time. I could put that 105 lens on again and take a colored picture.
001:54:33 Worden (onboard): Yes.
001:54:34 Scott (onboard): Colored picture? ...
001:54:36 Irwin (onboard): ... there's a requirement to do it.
001:54:38 Scott (onboard): Yes.
001:54:39 Irwin (onboard): ... - with the 105 lens.
001:54:41 Scott (onboard): Good idea, Why not do it?
001:54:43 Irwin (onboard): It's - it's not the same place, but -
001:54:47 Worden (onboard): Yes, yes - Well, there's no - no - If you want to take a color picture, they - what they want is a color picture to back up the scene you're seeing in the UV. So, if you can't get a color picture of that area, there's no sense taking it. But you might go ahead and take some pictures with the 80 millimeter. There's nothing wrong with that. On the...
001:55:22 Scott (onboard): Have you got the Update Book out, Jim?
001:55:25 Irwin (onboard): No, I don't.
001:55:26 Worden (onboard): Did you log - you didn't log the UV pictures in here, did you?
001:55:29 Irwin (onboard): Yes.
001:55:30 Worden (onboard): Where did you log them?
001:55:31 Irwin (onboard): Oh, on - in the photo procedures here ...
001:55:32 Worden (onboard): No, we want to log them on the - on the ...
001:55:58 Worden (onboard): Photo Log - 70 millimeter, Mag N, was it?
001:56:05 Irwin (onboard): Yes, Mag N.
001:57:27 Scott (onboard): Ohh! ...
001:58:13 Irwin (onboard): (Laughter) Get the - get the ... out.
001:58:17 Worden (onboard): (Laughter) Yes, I reckon. How's old Davy?
001:58:22 Scott (onboard): Oh, we're muttering along, flying across the sea.
001:58:32 Worden (onboard): ...
001:58:34 Scott (onboard): ...
001:58:40 Irwin (onboard): ...
001:58:50 Scott (onboard): ...
001:59:22 Worden (onboard): Do you have yourself strapped in the seat there, Dave ?
001:59:24 Scott (onboard): Yes. I do that most of the time, I think.
001:59:26 Irwin (onboard): Yes, I like to do...
001:59:27 Scott (onboard): It's a lot more comfortable. ... relative position.
001:59:30 Worden (onboard): Yes.
001:59:31 Scott (onboard): Because, otherwise, you're fighting the panel all the time.
001:59:33 Worden (onboard): Yes. My problem.
001:59:39 Scott (onboard): ...
001:59:40 Irwin (onboard): Why?
001:59:45 Scott (onboard): ...
001:59:48 Worden (onboard): We could take these lifevests ...
001:59:50 Scott (onboard): Yes, we could.
001:59:55 Worden (onboard): ...
Flight Plan page 3-5.
002:00:01 Scott (onboard): ...
002:00:11 Worden (onboard): Should we stow the lifevests?
002:00:14 Scott (onboard): Yes.
002:00:16 Irwin (onboard): Yes ...
002:00:17 Scott (onboard): Get that in there somewhere?
002:00:20 Worden (onboard): ...
002:00:38 Irwin (onboard): Not nearly as loud at 5 psi.
002:00:40 Scott (onboard): Yes.
002:01:12 Scott (onboard): Get your lifevest put away, Jim?
002:01:15 Irwin (onboard): Yes.
002:01:51 Scott (onboard): ... things on?
002:01:52 Irwin (onboard): Okay.
002:02:34 Scott (onboard): Got your ...?
002:02:40 Worden (onboard): Yes, I ...
002:02:50 Worden (onboard): Can't get it quite as tight as ...
002:02:59 Irwin (onboard): Where would you keep the Update Book?
002:03:07 Scott (onboard): R-3 is a pretty handy place for all those books up there.
002:03:15 Irwin (onboard): Do we have a strap?
002:03:18 Worden (onboard): Velcro ...
002:03:21 Scott (onboard): Is there a snap up there?
002:03:25 Irwin (onboard): No, ...
002:04:38 Worden (onboard): I think I see it now.
002:04:47 Scott (onboard): Ah, it'll be dark pretty soon. We'll get to see the never-never land. There's no horizon.
002:04:58 Scott (onboard): We got to have some place to put the ...
002:05:02 Irwin (onboard): Well, we could unhook it. Maybe - -
002:05:05 Scott (onboard): Matter of fact, why don't we get everything stowed for TLI? ... couple helmets - Why don't you put it down in the LEB somewhere, and we'll just leave them there until after TLI - -
002:05:15 Irwin (onboard): The helmets?
002:05:17 Scott (onboard): Yes.
002:05:18 Irwin (onboard): Yes.
002:05:19 Scott (onboard): Let's - let's just leave them until we get docked and start getting up into the tunnel...
002:05:23 Worden (onboard): Yes.
002:05:24 Scott (onboard): [Garble] put them on.
002:05:25 Worden (onboard): Okay.
002:05:36 Worden (onboard): Could just stick these PGA bags in there.
002:05:40 Scott (onboard): Yes.
002:05:41 Worden (onboard): Whoops! Did I do it again?
002:05:43 Scott (onboard): I don't know, did you?
002:05:44 Irwin (onboard): You're pretty consistent down there, Al.
002:05:47 Scott (onboard): I can't imagine you did that twice in a row.
002:05:56 Worden (onboard): [Garble].
002:05:57 Scott (onboard): Huh?
002:05:58 Worden (onboard): [Garble].
002:06:01 Scott (onboard): The emergency cabin regulator check book.
002:06:05 Worden (onboard): [Garble].
002:06:06 Scott (onboard): Huh?
002:06:07 Worden (onboard): [Garble].
002:06:08 Scott (onboard): Must have been.
002:06:14 Irwin (onboard): We're getting a good check at that, Al.
002:06:18 Scott (onboard): [Garble]. Watch your big feet.
002:06:54 Irwin (onboard): Are we going to eat before TLI?
002:06:57 Worden (onboard): You're kidding.
002:07:00 Scott (onboard): No, [garble].
002:07:06 Irwin (onboard): We need an emergency [garble].
002:07:12 Worden (onboard): Sort of an early time.
002:07:42 Worden (onboard): Okay, give me your helmet back there, Dave, and I'll stash it away.
002:07:46 Scott (onboard): Okay.
002:08:03 Irwin (onboard): Gets dark fast, doesn't it?
002:08:04 Scott (onboard): Yes, it does. Yes, you see never-never land out there?
002:08:06 Worden (onboard): [Garble].
002:08:16 Irwin (onboard): Yes. No - no horizon at all.
002:08:25 Worden (onboard): Anything else you want [garble]?
002:08:27 Scott (onboard): No, that's all right.
002:08:28 Irwin (onboard): Let's just take a look at this [garble]. Sort of interesting.
002:08:33 Worden (onboard): [Garble].
002:08:35 Scott (onboard): Yes.
002:08:36 Worden (onboard): [Garble].
002:08:50 Worden (onboard): [Garble].
002:09:00 Scott (onboard): What, that over there?
002:09:04 Worden (onboard): [Garble].
002:09:06 Scott (onboard): [Garble].
002:09:16 Irwin (onboard): Boy, that's - Look at that planet, how orange it is out there, Dave? Directly ahead.
002:09:21 Scott (onboard): Yes, it is. isn't it? How come we saw the same planet in the sunlight, Jim? Huh? Tell me that.
002:09:41 Worden (onboard): [Garble].
002:09:43 Irwin (onboard): It wasn't the same one.
002:09:44 Scott (onboard): Huh? Tell me that.
002:09:46 Irwin (onboard): Oh, you're - you're still saying it's a satellite, huh?
002:09:48 Scott (onboard): Well, I - I don't know what I'm saying now, because you convinced me it's a planet. But now, it's in the same position it was...
002:09:55 Irwin (onboard): Yes?
002:09:56 Scott (onboard): ...when we had sunrise as we go into sunset. So that tells me something.
002:10:01 Worden (onboard): [Garble].
002:10:08 Scott (onboard): Two hours 10 minutes and 7 seconds. Turn the lights out. [Garble] never-never [garble]. Now I can put the COAS on it. And for the COAS, [garble]. It's right on it. It's depressed - just about 18 degrees. [Garble]. Here we are. Here we are at Orb-rate. Time's going to be 10 - 2:10. Okay, I'm going to mark it. [Garble]. Get a writing pad. Two hours and 11 minutes exactly.
002:11:01 Scott (onboard): Mark. Two hours and 11 minutes. COAS is on - 7 degrees depressed below our image - our attitude towards the Earth.
002:11:24 Irwin (onboard): [Garble] that flash out there [garble].
002:11:27 Scott (onboard): Oh, that's the S-IVB.
002:11:28 Worden (onboard): [Garble] the S-IVB [garble].
002:11:31 Irwin (onboard): Okay.
002:11:34 Worden (onboard): Well, you know, that's got to be Saturn. Saturn is over by Scorpio.
002:11:44 Scott (onboard): Yes, it could be.
002:11:45 Worden (onboard): Yes, and Antares [garble].
002:11:57 Worden (onboard): [Garble].
002:12:00 Scott (onboard): Look at all the [garble].
002:12:05 Irwin (onboard): [Garble], Al. The Earth?
002:12:08 Scott (onboard): Yes.
002:12:19 Scott (onboard): Okay, let's see. We got everything stowed now?
002:13:13 Scott (onboard): Anybody want to eat anything now?
002:13:15 Worden (onboard): I'm going to wait until we get everything squared away after docking.
002:13:20 Irwin (onboard): [Garble] docking [garble].
002:13:23 Scott (onboard): What did you say?
002:13:24 Irwin (onboard): [Garble] Al [garble]. How about yours?
002:13:33 Scott (onboard): Okay. Is your suit dry today, Jim?
002:13:36 Irwin (onboard): Well, you haven't smelled too much urine, have you?
002:13:38 Scott (onboard): No.
002:13:39 Irwin (onboard): Okay, it must have worked then.
002:13:40 Scott (onboard): Good.
002:13:43 Irwin (onboard): Well, I'll tell you, I used it three or four times [garble]. (laughter).
002:13:46 Scott (onboard): Did you really?
002:13:47 Irwin (onboard): Yes. Three times before launch and once in orbit.
002:13:52 Scott (onboard): God, you really [garble].
002:13:55 Irwin (onboard): I really drank the Gatorade yesterday.
002:14:15 Scott (onboard): Twenty-six minutes to go before ignition.
002:14:20 Irwin (onboard): Yes, I have ignition at 2:50:31.
002:14:33 Irwin (onboard): You want to wait until we get AOS and then start through it?
002:15:11 Worden (onboard): We should have gotten [garble].
002:15:13 Scott (onboard): What?
002:15:14 Worden (onboard): [Garble].
002:16:47 Irwin (onboard): We changed [garble].
002:16:49 Scott (onboard): We have?
002:17:18 Scott (onboard): Getting ready to go to sleep?
002:17:20 Worden (onboard): No, lot of work to do [garble].
002:17:22 Scott (onboard): (Laughter) Yes. About time.
002:17:27 Worden (onboard): Yes, it is.
002:17:37 Scott (onboard): I've been feeling a little more full in the head all the time.
002:17:40 Worden (onboard): Yes.
002:17:41 Scott (onboard): And...
002:17:42 Irwin (onboard): You mean it gets more and more?
002:17:43 Scott (onboard): Well, for - it's up - everybody's a little different. For me, it gets a little more and more after the first - like 7 or 8 hours. And then it stabilizes, and you don't even notice it after the first night. I didn't. Ever - everybody's a little different. Your - your body adjusts - adjusts to the whole thing.
002:18:16 Worden (onboard): [Garble] feel tired quicker because we don't have anything to push against. Seems like ...
002:18:26 Scott (onboard): No.
002:18:27 Worden (onboard): [Garble] suddenly you don't have anything [garble].
002:18:29 Scott (onboard): No, I didn't feel any muscle fatigue [garble]. Well, Jim, why don't we go through this thing now? We're going to be [garble].
002:18:37 Irwin (onboard): Translunar to Inject.
002:18:39 Scott (onboard): [Garble].
002:18:40 Irwin (onboard): Verify.
002:18:41 Scott (onboard): That's a verify.
002:18:46 Irwin (onboard): EDS Power, on, up.
002:18:47 Scott (onboard): EDS Power, on, up.
002:18:50 Irwin (onboard): Perform EMS Delta-V test and null bias check.
002:18:52 Scott (onboard): Complete.
002:18:53 Irwin (onboard): Set Delta-VC.
002:18:55 Scott (onboard): Set to 10401.1.
002:18:59 Irwin (onboard): 10401.1.
002:19:01 Scott (onboard): Okay.
002:19:02 Irwin (onboard): EMS Function, Delta-V.
002:19:04 Scott (onboard): Delta-V.
002:19:05 Irwin (onboard): GDC Align.
002:19:07 Scott (onboard): Okay, I'm ... check that.
002:19:16 Scott (onboard): ... your ... box, it's real loose.
002:19:18 Worden (onboard): Oo-wee! That is.
002:19:20 Scott (onboard): ...
002:19:21 Worden (onboard): ...
002:19:30 Irwin (onboard): ... get that ... right.
002:19:54 Scott (onboard): Three degrees on the GDC at 2 hours.
002:20:00 Irwin (onboard): What was it? What?
002:20:05 Scott (onboard): Take 3 and a half degrees for 2 hours.
002:20:08 Worden (onboard): Three and a half in 2 hours ...
002:20:10 Scott (onboard): Yes.
002:20:27 Worden (onboard): ...
002:20:29 Scott (onboard): Ah. Yes, pitch and -
002:20:36 Scott (onboard): What was the pitch? But that makes sense because we're ... in pitch.
002:20:41 Worden (onboard): Yes.
002:20:43 Scott (onboard): Okay. The GDC's aligned.
002:20:46 Irwin (onboard): Okay. Check the - check the DAP.
002:20:55 Scott (onboard): 31102.
002:20:58 Irwin (onboard): Good.
002:20:59 Scott (onboard): 01111.
002:21:00 Irwin (onboard): Good. Okay, key Verb 83, at ORDEAL.
002:21:16 Irwin (onboard): You want to set ORDEAL, 90 and Earth.
002:21:19 Scott (onboard): It's 90 and Earth and it's tracking very nicely.
002:21:22 Irwin (onboard): Okay. Sequence Pyro Arm, two, to on, up.
002:21:25 Scott (onboard): Pyro Arm, two, on, up. Two on, up. Okay.
002:21:36 Worden (onboard): You didn't get P31 after you get - -
002:21:40 Irwin (onboard): Might be a ...
002:21:41 Worden (onboard): Get started.
002:21:42 Scott (onboard): Yes.
002:21:45 Irwin (onboard): Do you want to wait?
002:21:46 Scott (onboard): Yes. Let's do.
002:21:47 Worden (onboard): ... on the angle ... a good shape.
002:22:13 Irwin (onboard): ... to put that on and watch it?
002:22:14 Worden (onboard): Mm-hmm.
002:22:15 Irwin (onboard): Turn it?
002:22:16 Worden (onboard): Yes.
002:22:18 Irwin (onboard): It looks to me like you could turn it first.
002:22:20 Worden (onboard): No, do it yourself. It's running ...
002:22:27 Scott (onboard): Yes. Right on the money.
002:22:30 Irwin (onboard): I just don't believe we're here.
002:22:32 Worden (onboard): Yes. It's the greatest, for sure.
002:22:50 Scott (onboard): ...
002:22:52 Worden (onboard): That's for sure.
002:22:53 Scott (onboard): Yes.
002:22:54 Irwin (onboard): You think we'll ...?
002:23:22 Scott (onboard): It's not bad up here in zero-g either, is it?
002:23:24 Worden (onboard): No, hell no, it's not too bad at all.
002:23:27 Irwin (onboard): Don't even feel supper.
002:23:28 Scott (onboard): Did you - did you this morning?
002:23:31 Worden (onboard): Yes.
002:23:32 Scott (onboard): I can't imagine why people - some people suffer.
002:23:37 Worden (onboard): ...
002:23:38 Scott (onboard): Make sure you take your timer down, Jim, before we start the burn.
002:23:43 Irwin (onboard): Ah...
002:23:44 Worden (onboard): How about putting it up in there? Okay. Set it right before ...
002:23:50 Scott (onboard): As a matter of fact, get - get all that stuff secured. The S-IVB hasn't got much, but when we get down to the SPS stuff, why it's got a pretty good kick.
002:23:57 Worden (onboard): Yes.
002:23:58 Irwin (onboard): Sure. Well, it ought to be all right on the girth shelf, won't it?
002:24:04 Scott (onboard): I guess.
002:24:12 Worden (onboard): Well, the seat's kind of tight right underneath there.
002:24:14 Scott (onboard): Huh?
002:24:15 Worden (onboard): Just passed through the ...; we're in good shape.
002:24:23 Scott (onboard): Yes, should be right here.
002:24:25 Worden/Irwin (onboard): There it is.
002:24:27 Scott (onboard): Yes.
[Download MP3 audio file. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
This is Apollo Control; 2 hours, 24 minutes Ground Elapsed Time. We've just had acquisition [of signal] through the Carnarvon station and Gordon Fullerton [is] giving them a call at this time.
002:24:31 Fullerton: Apollo 15, Houston through Carnarvon. Over.
002:24:35 Scott: All right, Houston; [Apollo] 15 here. [You are reading] 5 by [5].
002:24:39 Fullerton: You're 5 by [5] also.
5 by 5 is a radio term where the quality of the voice is given marks out of five. The first figure represents the strength or loudness of the voice, the second its readability. 5 by 5 is 'loud and clear' whereas 5 by 2, for example, would represent rather loud though distorted voice communications. 2 by 5 would represent faint though clear speech. Its use is due to the aviation background of the crews and many others in the program.
002:24:41 Scott: Okay. [Pause.]
002:24:50 Scott: Houston, 15. We're down to the middle of the TLI Prep [on page L2-29], and everything's in order.
002:24:56 Fullerton: Roger.
Comm break.
002:26:06 Fullerton: 15, Houston.
002:26:07 Scott: Houston, 15.
002:26:10 Fullerton: We're showing the Manual Attitude switches in Rate... [correcting himself] in Min Impulse, and we recommend Rate Command.
Three switches, to the far left of the Main Display Console, alter the way the spacecraft attitude is controlled in roll, pitch and yaw. They have three positions; Accel(eration) Command, Rate Command, Minimum Impulse.
002:26:16 Scott: Roger. Rate Command. And the pyros are armed.
002:26:22 Fullerton: Roger.
Long comm break.
The pyrotechnic devices which will separate the CSM from the launch vehicle have been armed in case of a serious problem with the S-IVB.
Flight Director Gerry Griffin [is] preparing to poll his flight controllers, here in the Mission Control room, for Go/No-Go, which shows in the Flight Plan, to be passed up through one of the [ARIA] aircraft in the mid-Pacific. However, it looks like the Go/No-Go signal will be voiced up to the crew just prior to the Loss Of Signal here at Carnarvon. 22 minutes - Mark, 22 minutes to ignition for Translunar Injection.
002:29:47 Fullerton: Apollo 15, Houston.
002:29:50 Scott: Houston, 15.
002:29:52 Fullerton: You are Go for TLI.
002:29:54 Scott: Roger. Go for TLI. [Pause.]
002:30:04 Scott: And the S-IVB oxidizer looks like about 36 [psi]. The fuel looks like about 19 [psi].
002:30:11 Fullerton: Roger.
Long comm break.
The LOX pressure has not decayed far since the end of the first S-IVB burn. The CVS (Continuous Vent System) in the LH2 tank is properly regulating LH2 pressure at 19 psi. In about 10 minutes, at 002:40:25, Time Base 6 will commence. This launch vehicle time base provides the relative timing sequence for the restart of the J-2 engine on the S-IVB. 42 seconds into TB6, the sequence begins by igniting a burner which will heat helium to provide pressurisation of the propellant tanks.
[Download MP3 audio file. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
We've had Loss Of Signal at Carnarvon. However we will leave the circuit up live for the relays through the aircraft in mid-Pacific - relay through the Guam station, for any continuing conversation with the crew of Apollo 15. 17 minutes, 35 seconds to ignition for Translunar Injection. The S-IVB with the Apollo 15 spacecraft now weigh around 103,000 pounds - as you were - 309,630 pounds [140,448 kg]. After the burn is complete the spacecraft [mass] will have shrunk to 103 thousand pounds approximately [46,700 kg approx.]. After Translunar Injection burn, velocity will rise from the present 25,620 feet per second [7,809 m/s] to 35,655 feet per second [10,868 m/s], an increase of slightly over 10,000 feet per second [3,000 m/s].
About 20 minutes after burn cut-off, the S-IVB will maneuver to the separation attitude, and at 3 hours, 20 minutes Ground Elapsed Time, the Apollo 15 spacecraft will separate and do a turn-around maneuver and prepare to dock with the Lunar Module, which is housed in the spacecraft/LM adapter atop the S-IVB stage. The four panels will shed away. The spacecraft, after docking with the Lunar Module, is ejected from the S-IVB stage. The Lunar Module landing gear struts are attached at the knee joints to fittings inside the Spacecraft/Lunar Module [Adapter] or SLA as it is called in acronisms - acronym. Springs eject the spacecraft at slightly over 1 foot per second [0.3 m/s]. We're still about 2 minutes away from acquisition by the first of two ARIA aircraft, or Apollo Range Instrumented Aircraft. From then on, we should have fairly continuous coverage until Hawaii. And the Translunar Injection burn, which is now some 14 minutes, 6 seconds away from this point, will begin just at the start of the Hawaii pass and from then on, until going behind the Moon some three days from now, we'll have continuous coverage - continuous contact with Apollo 15.
We've had Acquisition Of Signal with the first ARIA aircraft. During the docking - separation and docking maneuver, we should have a live color television picture from the Command Module Westinghouse television camera.
002:30:45 Worden (onboard): Function Delta-V is on.
002:30:48 Scott (onboard): Mm-hmm, Don't bump your head on those lights ...
002:30:55 Worden (onboard): Yes, right.
002:30:57 Scott (onboard): Put your head back here in that little old cubbyhole.
002:31:00 Worden (onboard): Think that will help?
002:31:01 Scott (onboard): It might.
002:31:30 Scott (onboard): ... it's daylight. Think we can see this pretty burn ?
002:31:33 Irwin (onboard): Yes, I'm sure we will.
002:31:38 Worden (onboard): You ready?
002:31:39 Scott (onboard): Yes.
002:31:40 Worden (onboard): 809 ... 58.
002:31:41 Irwin (onboard): Sunrise at 2:48.
002:31:42 Scott (onboard): 58, Verb 48.
002:31:57 Irwin (onboard): Okay. Launch Vehicle Guidance, IU.
002:32:01 Scott (onboard): Verified.
002:32:03 Irwin (onboard): Okay. We're standing by for time base 6.
002:32:06 Scott (onboard): Okay.
002:32:15 Worden (onboard): What's EPS?
002:32:16 Scott (onboard): Burn time - 5:55. And, when you get the shutdown, you got a 2-second thruster VI. Right?
002:32:27 Worden (onboard): Right.
002:32:29 Scott (onboard): ... degrees per second rate. The first one is at 59. Make sure you got that. 45 degrees pitch and yaw.
002:32:39 Worden (onboard): That's 48 deg - degrees.
002:32:42 Scott (onboard): ... degrees per second roll. The S-IVB guidance function ... Okay.
002:33:14 Scott (onboard): Do we have Hawaii all the way through the burn?
002:33:18 Irwin (onboard): I don't think so.
002:33:20 Worden (onboard): No, we haven't .... No, we have...
002:33:23 Irwin (onboard): AOS at 2:5 ...
002:33:24 Scott (onboard): We go through a keyhole ...
002:33:25 Irwin (onboard): LOS at ...
002:33:26 Worden (onboard): No. We have LOS at 49:52 for ... minutes.
002:33:30 Irwin (onboard): No, we get them back at 2:55.
002:33:49 Scott (onboard): Ooh.
002:34:32 Scott (onboard): Yes, well, we tried it the other day.
002:34:34 Worden (onboard): Yes.
002:34:35 Irwin (onboard): I hope so.
002:34:36 Worden (onboard): If you did, you can change your Delta-V ... 20 feet per second.
002:35:07 Scott (onboard): There's ullage.
002:35:08 Worden (onboard): Yes.
002:35:09 Irwin (onboard): I bet you it's from the S-IVB.
002:35:17 Scott (onboard): Huh?
002:35:20 Irwin (onboard): You're running about an 80-amp load.
002:36:16 Irwin (onboard): ... what that was?
002:36:25 Worden (onboard): ...
002:36:39 Irwin (onboard): We're down to 5 on the cabin.
002:36:43 Scott (onboard): Get that waste vent closed.
002:36:47 Worden (onboard): When do we close that?
002:36:48 Scott (onboard): When we get ready to dock, and the cabin's up to 5 pounds.
002:36:52 Worden (onboard): I thought we were supposed to leave some pressure for that.
002:36:57 Irwin (onboard): I think we do.
002:36:58 Worden (onboard): Right after - -
002:36:59 Scott (onboard): Right after TLI?
002:37:00 Irwin/Worden (onboard): Yes.
002:37:01 Worden (onboard): I think we do it.
002:37:04 Irwin (onboard): Right after Waste Stowage Vent, Closed.
002:37:57 Scott (onboard): There's ARIA.
002:38:00 Irwin (onboard): Keep - keep looking.
002:38:02 Worden (onboard): ...
002:38:22 Fullerton: Apollo 15, this is Houston through ARIA. Over. [No answer.]
002:38:31 Scott (onboard): You don't have the S-band squelch on, do you?
002:38:35 Irwin (onboard): Yes, yes, I thought it was...
002:38:37 Scott (onboard): ... we ought to be able to get that ...
002:38:40 Scott (onboard): Oh, that's pretty - that is loud. Isn't it?
002:38:42 Irwin (onboard): Yes.
002:38:45 Fullerton: Apollo 15, this is Houston through ARIA. Over.
002:38:51 Scott: Rog, Houston, 15. You're about 1 by 1 through ARIA. [i.e. very poor.]
002:38:57 Fullerton: Roger. You're about 3 by [3]; clear enough to understand.
002:39:04 Scott (onboard): What'd he say?
002:39:05 Worden (onboard): He said we're clear enough ..., I think.
002:39:10 Scott: Roger. We have somebody else on the loop with us, too.
Comm break.
Coming up on 10 minutes to TLI ignition. Mark, 10 minutes.
002:39:22 Worden (onboard): ...
002:39:25 Scott (onboard): ... Uplink Activity light.
002:39:27 Worden (onboard): Okay.
002:40:02 Scott (onboard): It's a familiar sound, and I can't remember what I - what it is.
002:40:07 Worden (onboard): Just a minute ...
002:40:08 Scott (onboard): You can't change the frequency there. You might hook up...
002:40:12 Worden (onboard): It seems to...
002:40:19 Irwin (onboard): It's a bull's-eye.
002:40:20 Worden (onboard): Why don't we hook up the speakers, and let's do some checking...
002:40:25 Scott (onboard): Don't count too far.
002:40:27 Worden (onboard): S-II Sep light.
002:40:28 Irwin (onboard): Yes.
002:40:29 Worden (onboard): It just came on, Dave.
002:40:30 Scott: We have the S-II Sep light?
002:40:33 Irwin (onboard): You stand...
002:40:33 Fullerton: Roger. Sep light.
Comm break.
002:40:37 Scott (onboard): Okay.
Layout of launch vehicle indicator lamps
Layout of launch vehicle indicator lamps
On the left of the Main Display Console there are a cluster of launch vehicle annunciator lights. Five of these are arranged in a pattern similar to the layout of engines on the S-IC and S-II stages and provide the crew with cues of each engine's status. Above are three lights which indicate other events. The central light of these three is labelled "S-II Sep," a label only relevant to the light's first functions as it is reused to indicate other later events. By using the same lights for multiple functions in the spacecraft, designers could save on precious panel space and weight by not duplicating monitoring lights for systems that would only be used for a tiny fraction of the journey.
As per page 2-30 of the Launch Checklist, the "Uplink Activity" and "S-II Sep" lights comes on, indicating the start of Time Base 6, the S-IVB restart sequence. TB-6 begins at 002:40:23 GET leading to an eventual ignition at 002:50:01 GET; 9 minutes, 38 seconds later. The "Uplink Activity" lamp goes out after ten seconds while the "S-II Sep" lamp goes out after 38 seconds, exactly nine minutes to ignition. To help the crew orchestrate their actions before and during TLI, the Mission Timer is preloaded to 51:00. When the "S-II Sep" lamp indicates nine minutes to go, the timer is started and counts up so that reaching 00:00 should coincide with ignition. The checklist is marked with times that match the 'count-up', aiding the crew in following events as they occur.
Originally, we were not sure how long the "S-II Sep" light came on for. The checklist makes it clear that the "Uplink Activity" light goes out after ten seconds. Eventually, it was pointed out by Journal contributor, Lennie Waugh, that the Apollo 12 Launch checklist specifically states that the "S-II Sep" comes on for 38 seconds.
The crew is now in the middle of page 2-30 and they are monitoring the repressurisation of the S-IVBs fuel and LOX tanks.
002:40:43 Irwin (onboard): The Uplink Activity light went out.
002:40:45 Scott (onboard): Okay.
002:41:08 Irwin (onboard): Okay. Monitor launch-vehicle tank-pressure sequence.
002:41:11 Scott (onboard): Very well. It should come on now. Come on, baby.
002:41:34 Scott (onboard): Here it comes. Come on.
002:41:44 Worden (onboard): It might fool you ...
002:41:46 Scott (onboard): Yes.
002:41:53 Scott (onboard): And coming up on 52 minutes.
002:41:57 Irwin (onboard): Okay. ORDEAL FDAI 1 to Orb-rate; 2 to Inertial.
002:42:05 Scott (onboard): Okay, stand by one.
002:42:06 Scott: Okay, Houston. It looks like we have a slow repress start. We're up to about 22 to 23 on the fuel pressure.
The fuel tank pressure has to rise from 19 psi [131 kPa] to its operational value of 30 psi [207 kPa].
Scott, from the 1971 Technical debrief: "The one thing that I noticed, which was a fair surprise, was that the helium repress was very slow compared to the CMS [Command Module Simulator]. In the simulator, helium repress goes very rapidly, and pressure on the oxidizer tank comes right up. In this case, it came up very slowly. It was almost an imperceptible beginning. I called the ground and questioned them on it. They called back and said it was a normal repress. I think we ought to have the simulator people take a look at that. It was a little bit of concern even though we had the ambient bottle if we didn't have the repress. But in the back of my mind, I was wondering what was wrong, and nothing was wrong."
The ambient bottle Dave refers to is one of the nine helium storage spheres mounted on the outside of the S-IVB's thrust structure next to the J-2 engine. Unlike the helium tanks mounted inside the S-IVB's fuel tank which are therefore very cold, the ambient spheres are not cooled and rely on high pressures to store their contents.
Scott (onboard): Okay. Orb-rate, Inertial.
002:42:17 Irwin (onboard): Okay; ORDEAL Mode, Hold/Fast.
002:42:17 Fullerton: Roger, Dave. You're just barely readable. Understand you're getting a normal Repress. We're - It looks good down here.
002:42:20 Scott (onboard): Hold/Fast. Go on.
002:42:22 Irwin (onboard): All right.
002:42:26 Scott: Okay. Normal Repress.
Long comm break.
During the TLI burn, the guidance of the vehicle will be monitored using the FDAI in front of the Commander. The Saturn third stage will pitch up at a preprogrammed rate as the burn continues and the ORDEAL will drive the FDAI at a matching rate to compensate for the pitch motion. This will allow the FDAI to indicate a zero attitude all through the burn. Therefore, if necessary, the burn could be steered manually by Dave, just by keeping the FDAI and the associated rate needles zeroed. Checklist lines at the bottom of page 2-30 and the top of 2-31 deal with setting up the FDAI and ORDEAL in preparation for this.
Scott (onboard): Go, Jim.
002:42:34 Scott (onboard): Okay; 300 on the Lunar.
002:42:36 Irwin (onboard): And RH...
002:42:39 Scott (onboard): Armed.
002:42:40 Irwin (onboard): Uptelemetry, CM and IU, both to Block.
002:42:43 Scott (onboard): Block's on.
002:42:44 Irwin (onboard): Standing by for 56 minutes.
002:42:48 Scott (onboard): At 54, we go 25 degrees.
002:42:53 Irwin (onboard): What - what was that on repress that you ... normal?
002:42:57 Scott (onboard): It's - it's just something that's a little slow in here.
002:42:59 Irwin (onboard): Oh.
002:43:00 Scott (onboard): It's normally quite fast. ... At 54 minutes, we want to be at 25 degrees.
002:43:39 Scott (onboard): Wonder who all that is?
002:43:40 Worden (onboard): Yes, I wonder?
002:45:01 Scott (onboard): Coming up on 55 minutes.
002:45:04 Irwin (onboard): ...
002:45:08 Scott (onboard): Okay. Coming up ...
002:45:10 Irwin (onboard): Okay; at 56, slew FDAI 1 to Pitch at 17.
002:45:59 Scott (onboard): Okay. ...
002:46:00 Irwin (onboard): Seventeen.
002:46:04 Irwin (onboard): Okay; at 56:45, it should be 14 degrees.
[Download MP3 audio file. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Plot boards here in Mission Control Center on the center screen are being set up now to monitor the Translunar Injection burn. Some 5 minutes, 43 seconds away from ignition. Should be in about a minute and a half acquired by the second ARIA spacecraft - [correcting himself] aircraft in mid-Pacific. BOOSTER reports that the tanks in S-IVB stage have been pressurized.
002:46:08 Fullerton: Apollo 15, Houston through ARIA number 2. Over.
002:46:11 Scott (onboard): ... talking to him.
002:46:14 Scott: This is 15. Say again.
002:46:17 Worden (onboard): We lost him, Dave.
002:46:18 Fullerton: 15, Houston. You're way down in the static, but I can hear you transmit. Over.
002:46:27 Scott: Okay. We'll pick you up at the keyhole.
Comm break.
Scott (onboard): You ought to be ORDEAL, Operate. Right?
002:46:36 Irwin (onboard): Yes, Operate/Slow.
002:46:38 Scott (onboard): What angle? 14 degrees?
002:46:42 Irwin (onboard): Fourteen degrees.
002:46:46 Worden (onboard): ...
002:46:49 Scott (onboard): Minus.
002:47:13 Worden (onboard): Daylight?
002:47:15 Irwin (onboard): Yes.
002:47:30 Irwin (onboard): Why don't they have a picture like that in the simulator?
002:48:01 Worden (onboard): Two hours and 48 minutes.
002:48:17 Scott (onboard): ... Blank ....
002:48:21 Irwin (onboard): TVC Servo - SCS TVC Servo Power 1 to AC 1/Main A.
This is Apollo Control. There was some doubt in the BOOSTER Engineer's mind that the engine bell of the S-IVB J-2 engine had been properly chilled down from the data that he got through the ARIA 1 aircraft. However, his new data coming in through ARIA 2 has confirmed that the chilldown procedure prior to start has been accomplished as scheduled. Some 2 minutes, 15 seconds away from TLI ignition. Continuing to standby as we approach acquisition at Hawaii in some 2 minutes from now. Still standing by through the ARIA 2 aircraft. Communications through ARIA 2 have been somewhat scratchy - almost unintelligible from the spacecraft.
002:48:25 Scott: Average g is on.
002:48:28 Irwin (onboard): Two, off.
002:48:28 Fullerton: Roger. Average g.
Average g is the process of averaging out the acceleration experienced during a burn. It is used to reduce the error inherent in sampled (digital) data. The DSKY blanks at about 1 minute, 45 seconds before ignition. Five seconds later, it returns displaying the time relative to ignition, the velocity to be gained and the overall inertial velocity of the spacecraft. This data is based on the output from the spacecraft's accelerometers and indicates that "Average g" mode has begun. These displays give the crew a confirmation that the Guidance & Navigation system is operating properly.
The motors which drive the gimbals to point Service Module's engine are powered up in case the CSM has to depart from an errant booster. The DSE (Data Storage Equipment), essentially a tape recorder, is set to record the spacecraft's telemetry throughout the burn.
002:48:32 Irwin (onboard): Tape Recorder's going High Bit Rate.
002:48:39 Scott: Sep light.
002:48:43 Fullerton: Roger. Sep light.
Comm break.
At 1 minute, 24 seconds to go, the "S-II Sep" light comes on again. Soon after, the APS (Auxiliary Propulsion System) modules at the base of the S-IVB fire to settle the contents of the tanks. This ullage burn also provides an initial head of pressure of the propellants towards the engine's turbopumps.
002:48:44 Scott (onboard): Thrust mode, Normal.
002:49:33 Scott (onboard): Put it in between the camera, Al. No, don't force it.
002:49:37 Worden (onboard): ... Jim.
002:49:38 Scott (onboard): Can you get it up there?
002:49:48 Scott (onboard): Okay. Get ready, gang.
18 seconds before ignition, the "S-II Sep" light goes out to signal the final phase of starting the J-2. On this starting sequence, the supercold fuel will flow through the combustion chamber walls for 8 seconds to condition them prior to discharge of the Start Tank's GH2 through the turbines to spin them up. Previously, this was for only one or three seconds but the J-2 has been exposed to the heat of the Sun and is expected to take longer to chill down. A full description of the J-2 engine and its ignition sequence is at 000:02:58 in the Journal.
Communications are now through the tracking station in Hawaii.
Looking at ignition time of 2 hours, 50 minutes, 1 second Ground Elapsed Time. Cut-off at 2 hours, 55 minutes, 54 seconds. Total spacecraft velocity at cut-off should be 35,608.7 feet per second [10,853.5 m/s]. Coming up on 20 seconds. Mark, 20 seconds to TLI ignition.
002:49:57 Scott (onboard): Okay, 8 seconds. Three [garble].
One second before ignition, the light for the number one engine in the cluster of five indicator lights comes on. Actual S-IVB ignition is at 002:50:02.6 GET and two seconds later the light goes out. When the light next comes on, it will be to announce engine cut-off and the end of the burn.
002:50:03 Scott (onboard): Fire is on.
002:50:04 Scott: We have ignition.
002:50:05 Fullerton: Roger; ignition. [Pause.]
002:50:15 Scott (onboard): Okay. We're pitching now.
002:50:17 Worden (onboard): ... full, high.
002:50:17 Fullerton: 15, Houston; we're showing good thrust. [Long pause.]
002:50:22 Scott (onboard): Okay. Yes.
Velocity building up. Now 26,270, 26,347 feet per second [8,007, 8,031 m/s]. Resulting apogee building up, now 679 [nautical] miles [1,258 km], 706 [1,308]: clicking over very rapidly.
002:50:27 Scott (onboard): It's tracking's real good.
002:50:36 Scott (onboard): Load's about a half a g. ORDEAL ... should be tracking with it.
002:51:03 Scott (onboard): Well, it had a little surge right at this ...
002:51:05 Worden (onboard): Picked up right there.
002:51:13 Scott: Okay. S-IVB pressure is 40 [psi for the LOX tank] and 30 [psi for the fuel tank] and we had a little surge at about one minute.
002:51:20 Fullerton: Roger. That was PU shift and that looks - the thrust looks good.
002:51:26 Scott: Okay.
Comm break.
Fifty four seconds after ignition, the mixture ratio control valve operates, altering the ratio of fuel to oxidiser to ensure maximum propellant utilisation or PU. At this point, the thrust rises to its nominal level of about 890 kilonewton (200,000 pounds).
Scott, from the 1971 Technical debrief: "One minute after ignition on the S-IVB we had PU shift, which we hadn't been aware of and which we weren't expecting. We did feel a very noticeable change in thrust, and that hadn't been discussed preflight. It was something, I guess, we just missed along the way. It seemed strange to me that we didn't have it in our checklist or time line. We had the PU shift for launch, and I think it, might be a nice thing to stick in the TLI time line also, just so you'll know it's going to happen. It's no big deal."
Mission planners have taken account of the possibility that the TLI burn could have been delayed by one orbit. Knowing that the LH2 fuel is constantly boiling off, they have allowed a small excess to compensate. Then, with a successful boost to the Moon at the first planned opportunity, the engine is set to run fuel-rich at a ratio of 4.5:1 for the first 56.5 seconds of the burn. After the PU shift, the mixture ratio changes to 5.0:1. Had TLI been delayed one orbit, almost the entire burn would have been made at the leaner ratio with the shift coming soon after ignition.
Velocity continuing to build, 26,700 feet per second [8,140 m/s]; resulting apogee 1,661 [nautical miles, 3,076 km].
002:51:33 Scott (onboard): You feel a very slight amount of bumping ...
002:51:37 Worden (onboard): Yes, it does.
002:51:39 Irwin (onboard): Could have been vibration.
002:51:41 Worden (onboard): Or trouble.
002:51:52 Scott (onboard): Yaw's tracking at about 1 degree.
002:51:53 Irwin (onboard): ORDEAL's right on the money.
002:52:02 Worden (onboard): Track is Go ....
002:52:16 Scott (onboard): Coming over the Hawaiian Islands.
002:52:40 Worden (onboard): Pressures are steady. ORDEAL's tracking.
Coming up on 30 thousand... [PAO is interrupted by Dave Scott]
002:52:54 Scott: Okay, Houston, 15. And we're about halfway through. Pressures are steady at 40 [psi] and 30 [psi] and ORDEAL is tracking right on through.
002:53:01 Fullerton: Roger, 15. At 3 minutes, it looks completely nominal to us.
002:53:07 Scott: Roger.
Comm break.
Scott, from the 1971 Technical debrief: "The new procedures that Mike Wash worked out for the TLI, putting that automatic and manual together, were really good. The ORDEAL setup was just right. The numbers came out just right, and ORDEAL track was right on zero until the last minute when the guidance starts trimming things out. Had we been required to fly a manual TLI, the ORDEAL would have been excellent because it really worked well."
Worden, from the 1971 Technical debrief: "That procedure is nice, too, because it is easy to keep up with. It is sequenced in the checklist so that there are plenty of check points in there so you can get everything squared away. It really works best."
Scott, from the 1971 Technical debrief: "Yes, if you ever had to step into a manual TLI, you could do it about any place and wouldn't be behind. I think you did a good job on that."
Coming up on 30,000 feet per second - Mark. 30,000 feet per second [9,144 m/s]. Resulting apogee, 4,685 nautical miles [8,677 km].
002:53:22 Scott (onboard): Delta-VCG.
002:53:24 Worden (onboard): My countdown's going to be off probably 2 seconds here. Let's start my watch and ... it again. I want to be sure the engines ... start.
002:53:36 Scott (onboard): You can feel it, can't you?
002:53:38 Worden (onboard): Yes.
002:53:41 Irwin (onboard): Converter's started.
002:53:42 Worden (onboard): Pitchover's...
002:53:43 Irwin (onboard): I get the little surge before the bang.
002:53:47 Scott (onboard): Okay, we're on P45.
002:53:50 Worden (onboard): Pressure's looking good. ORDEAL's tracking. A quarter g - a half g ...
002:54:00 Irwin (onboard): That computer has ... DSKY ...
002:54:04 Worden (onboard): That computer ...
002:54:06 Scott (onboard): Really?
002:54:14 Worden (onboard): 31,925.
002:54:37 Irwin (onboard): ... pressure.
002:54:39 Scott (onboard): Okay.
002:54:41 Irwin (onboard): ... Houston.
002:54:56 Scott: Okay, Houston. We have about a minute to go. We're tracking 39 and 30 on the pressures and ORDEAL's about zero.
Scott, from 1998 correspondence: "The objectives and settings for ORDEAL during TLI were different from its use in Earth or lunar orbit. For TLI, ORDEAL was set to drive the FDAI [8-ball] at a pitch rate equal to the S-IVB IU-programmed attitude change such that the center of the FDAI remained at zero; that is, the artificial horizon was always level, or at zero displacement. Also, as I recall, the attitude error needle was nulled [remained at zero if the actual S-IVB pitch rate was correct]. This provided a display for the CDR to both monitor the S-IVB performance as well as to takeover and fly [control] the S-IVB in its proper pitch rotation in the event the IU failed. ORDEAL was not, in this case, set to an 'orbit rate,' it was set at a programmed pitch rate."
002:55:03 Fullerton: 15, Houston; Roger. Looks good here. [Pause.]
002:55:06 Worden (onboard): O2 flow, high.
002:55:14 Scott (onboard): That should be on for cut-off.
002:55:17 Irwin (onboard): Yes, that's right.
002:55:19 Fullerton: 15, Houston. We're estimating cut-off about 4 seconds earlier than the PAD time.
002:55:25 Scott: Roger. Understand; 5 plus 51.
002:55:28 Fullerton: That's affirmative. [Long pause.]
The PAD, read up to the crew at 001:38:07, gave an estimated burn time of 5 minutes and 55 seconds based on predicted engine performance. The actual time for engine cut-off is controlled by the guidance systems in the IU determining that the spacecraft has reached the required velocity. If the engine over- or under-performs, actual cut-off will change accordingly. A slightly low thrust means a longer burn. In this case, the J-2 is producing a slightly better than expected performance and this has shortened the burn by 4 seconds.
Scott, from the 1971 Technical debrief: "I guess we all felt that same low amplitude 10 or 12 cps [cycles per second] vibration all the way through S-IVB burn, just like we did during the launch. And we got a call from the ground on, it seems to me, a 3-second-early shutdown."
Velocity rapidly approaching TLI cut-off speed.
002:55:32 Worden (onboard): I'll give you a countdown to 55.
002:55:42 Scott (onboard): Go ahead ... Go to ...
002:55:46 Worden (onboard): Okay. Here's the countdown.
002:55:47 Scott (onboard): Okay.
002:55:48 Worden (onboard): 10, 9, 8, 7, 6, 5, 4, 3...
002:55:55 Scott: Okay.
002:55:56 Scott: Shutdown, 5 plus 51.
Scott (onboard): Okay. Cameras...
The Number 1 light on the launch vehicle indicator comes back on to indicate engine cut-off. It also signals the beginning of Time-Base 7, concerned with controlling the pressure in the S-IVB fuel tank, and with control of the Saturn's attitude in preparation for the separation and docking manoeuvre.
002:55:58 Fullerton: Roger. [Long pause.]
002:56:02 Worden (onboard): ... stuff down here.
002:56:07 Scott (onboard): Okay. Al, get the data there.
002:56:09 Worden (onboard): Yes.
002:56:10 Scott (onboard): Check S-IVB tank pressures.
002:56:12 Scott: S-IVB [fuel] tank pressure is about 32 [psi], coming down. The oxidizer at about 28 [psi], coming down on the fuel.
002:56:21 Fullerton: Roger. [Long pause.]
Cut-off. Velocity; 35,522 feet per second [10,827 m/s]. Resulting apogee from that maneuver; 290,682 nautical miles [538,342 km].
While the S-IVB continues firing during TLI, Mission Control are calculating the resulting apogee which would be reached if the booster's engine were to cut-off immediately. At the planned engine cut-off, the apogee was given as 538,342 km, based on a speed of 10,827 m/s. This apogee figure does not take into account the intervention of the Moon's gravity on the spacecraft's trajectory. Bringing this into consideration, the flight dynamics team calculate that the S-IVB burn will result in a 257.4 km (139 nautical miles) pericynthion (the trajectory's closest point to the Moon), instead of the intended 146.3 km (79 nautical miles). The upcoming manoeuvres to extract the LM from the top of the S-IVB will reduce the pericynthion by about 18.5 km (10 nautical miles). Two midcourse manoeuvres will further bring the achieved pericynthion to 125.9 km (68 nautical miles).
002:56:23 Scott (onboard): SCS TVC Servo Power went Off - went Off. PCM Bit Rate going Low.
002:56:49 Irwin (onboard): FDAI 1 to Inertial.
002:56:52 Scott (onboard): Yes.
002:56:53 Worden (onboard): RHC number 2, locked.
002:56:55 Scott (onboard): Inertial and locked. Okay, when Al gets through with ...
002:57:02 Irwin (onboard): Okay, it's time to switch around.
002:57:04 Scott (onboard): Okay.
002:57:12 Worden (onboard): ...
Soon after losing contact through Hawaii, the spacecraft is picked up by the MSFN (Manned Space Flight Network, pronounced 'misfin' by the crews). Coverage will be continuous for the coast to the Moon with this first portion being via Goldstone in California and subsequently through Honeysuckle Creek in Australia and Madrid in Spain. Communications will rotate through these three as Earth turns.
002:57:16 Scott: Okay, Gordo. Got some data for you, if you're ready to copy.
002:57:22 Fullerton: 15, Houston. We're getting a lot of static for some reason. Say again, please.
002:57:27 Scott: Roger, Gordo. I've got the cut-off residuals when you're ready to copy.
002:57:32 Fullerton: Go ahead.
002:57:35 Scott: [Initially faint.] Okay. We cut-off on a VI of 35,614 [fps]. TFC was plus 02; VG was plus 145; Delta-VC was minus 14.9. And I've got the H-dot now if you want it. H-dot was 4,353 [fps] and altitude is 167.4 [nautical miles].
002:58:07 Fullerton: 15, Houston. Most of your readback is blocked by static. Let's wait a little while and try it again.
002:58:14 Scott: Okay, Gordo. [Long pause.]
002:58:15 Scott (onboard): Okay, you got all your data, Al?
002:58:17 Worden (onboard): Yes. The EMS is off.
002:58:19 Scott (onboard): Okay. Let's switch over. Okay. Switchy, switchy.
002:58:23 Irwin (onboard): Okay, when the Comp Activity light's out, you're just supposed to ..., Al.
002:58:27 Worden (onboard): ... switchy, switchy.
002:58:30 Scott (onboard): I need a Verb 66.
002:58:31 Worden (onboard): Okay.
002:58:35 Scott (onboard): Then when you all get down in the LEB, get that waste storage vent valve closed.
002:58:40 Worden/Irwin (onboard): Yes ...
002:58:47 Scott: And, Houston, we have the S-IVB in Orb-rate.
The orb rate maneuver puts the spacecraft heads down, rotating at 0.3° per second to keep it in a constant attitude with respect to Earth's surface below.
Worden, from the 1971 Technical debrief: "One further thing on TLI. I guess we wrote them down in the Flight Plan, but the [velocity] residuals on the CMC at the end of TLI were very close to zero. We wrote them down. The CMC kept very good track of the TLI burn."
002:58:51 Fullerton: Roger. You're loud and clear now.
002:58:54 Scott: Okay. [Long pause.]
002:59:16 Scott: Okay, Houston. I've got the data if you want to copy.
002:59:20 Fullerton: Okay. Sounds good now. Go ahead again.
002:59:24 Scott: Okay. DSKY was 35599; VG plus 145; and the Delta VC, minus 14.9; TFC, plus .02. [Pause.] And, for your information, the H-dot was 4353 and the H was 167.4 at cut-off.
Flight Plan page 3-6.
At cut-off, the DSKY displayed their current speed as 35,599 fps (10.850.6 m/s). VG is a measure of velocity to be gained, and was 145 fps (44.2 m/s). H-dot is the rate of change of height (or the time-derivative of height) and was 4,353 fps (1,326.8 m/s) and the height was 167.4 nautical miles (310 km). The value for H-dot is much less than the final velocity because a large component of that velocity was still parallel to Earth's surface. As Earth curves away from the departing spacecraft, the altitude will mount steadily, and H-dot will become a greater proportion of the overall velocity. Dave's call of VC refers to the velocity display on the EMS after the burn finished.
003:00:01 Fullerton: Roger. Say again what that figure 'plus 02' was?
003:00:07 Scott: Yeah. TFC.
003:00:12 Fullerton: Roger. Okay. Copied all that. And, for your information, the maneuver to the TD&E [Transposition, Docking and Extraction] attitude should start about one second earlier than the Flight Plan. 3:10:53.
003:00:26 Scott: Roger. 3:10:53.
Previous Index Next
Launch and Reaching Earth Orbit Journal Home Page Transposition, Docking and Extraction