The change of shift press conference takes place at about 2:15 am Houston time on December 27. With the mission proceeding smoothly and following a fairly quiet shift, combined with the fact that the re-entry is a few short hours ahead, this press conference is not surprisingly very brief. After only ten minutes, the press have run out of questions and Cliff Charlesworth actually offers to stay for a few more minutes.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Milt Windler and the Maroon Team now take over for the final shift of the mission. Splashdown is less than eight hours away. Ken Mattingly is at the CapCom console.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
This is Apollo Control at 139 hours, 15 minutes. At the present time Apollo 8 is at an altitude of 51,198 nautical miles [94,819 km] and our velocity is 8,698 feet per second [2,651 m/s]. A short while ago we had this conversation with Bill Anders.
139:19:13 Mattingly: Apollo 8, we'd like to have you, before you get in a P52 going here, we'd like to have you re-zero the optics and read us the mechanical CDUs. We're trying to collect a little data for troubleshooting.
139:19:29 Anders: Roger. Stand by.
139:19:31 Mattingly: Thank you. [Long pause.]
139:19:45 Anders: What's the trouble you're trying to troubleshoot?
139:19:51 Mattingly: This goes back to some of the problems we had prior to LOI; trying to see if the software readouts we're getting down here compare with the mechanical readouts. It's not a current problem as far as we know.
139:21:33 Mattingly: Okay. Why don't you just read me the mechanical CDUs there now, and then it looks from the ground like you're clear to go ahead with the P52.
139:21:44 Anders: Okay. We'll get the navigator squared away here in just a minute.
139:21:51 Lovell: Good morning, Captain.
139:21:53 Mattingly: Good morning, sir.
139:21:57 Lovell: This'll be a P52 out of a deep sleep. Okay, stand by one. [Long pause.]
139:22:17 Lovell: The trunnion mechanical CDU looks like it's reading about one one-hundredth.
139:22:25 Mattingly: Roger. [Long pause.]
139:22:52 Lovell: And the shaft mechanical C - OCDU looks like it's reading about four hundredth below zero, which would be about, what, 364. Yeah.
139:23:12 Mattingly: Understand, Jim. That's four hundredth below zero on the shaft; is that affirm?
139:23:17 Lovell: Yes. Stand by one. [Pause.] About 35996 I get.
139:23:27 Mattingly: Okay. Thank you. And you can go ahead with P52 now.
139:26:34 Mattingly: Okay. It looks like we're getting down on the Service Module RCS to the place where we ought to go ahead and activate the secondary Service Module RCS propellant.
139:26:48 Anders: Okay. Stand by.
Comm break.
Each of the four RCS clusters around the Service Module has its own fuel and oxidiser supply. Within each cluster, there are primary and secondary tanks of propellant, making four tanks. The mission up to now has been run using only the primary tanks but it is difficult to accurately determine how much propellant has been used. Therefore, when calculations suggest a certain level has been reached, around forty percent, the crew switch over the the full secondary tanks. By doing so, everyone now knows exactly how much propellant remains.
139:28:36 Mattingly: Okay. We've got a new PTC attitude. For the pitch, 180; and the yaw, 315.
139:28:45 Anders: Roger. Yaw, 315.
139:28:48 Mattingly: Roger. And pitch, 180.
139:28:52 Anders: Okay.
139:28:57 Anders: Could you pick one a little further away?
139:29:02 Mattingly: Not in our normal sphere. [Long pause.]
139:29:48 Lovell: Ken, this is Jim.
139:29:51 Mattingly: Go ahead.
139:29:52 Lovell: Aren't we still a little high on the quantity side to activate the secondary?
139:30:01 Mattingly: Negative. We have - let's see, we have quad Bravo and quad Delta which are getting right down, according to the calculated numbers, next to where we ought to be activating them. The numbers you're reading are going to be a little bit high, but the computer data on the ground shows that you have about 134 pounds in Bravo and Delta, and about 130 pounds is where you ought to be on the secondary.
139:30:33 Lovell: Okay. Roger. We'll activate the secondary and turn off the primary.
139:30:40 Mattingly: Okay. It's just to keep you from running one of them out.
139:30:44 Lovell: Rog.
Comm break.
The full load of each quad is about 335.6 pounds (152.2 kg). 130 pounds represents 38.7 percent of total.
139:31:54 Lovell: Secondary activated.
139:31:57 Mattingly: Roger.
Very long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control here at 139 hours, 52 minutes; and a good, good morning from the Maroon Team. We're 48,000 [nautical] miles [89,000 km] from home, moving at nearly 9,000 feet per second [2,750 m/s]. And in the last half hour we've had these bits and pieces of conversation with the crew. Among other items of interest, Jim Lovell awakened, which you may already know. He awakened a little bit earlier than his planned seven-hour sleep period; he was awake at least a half an hour ago. Here's our recorded conversation.
140:28:17 Borman: Ken, on this maneuver, MCC-7, are you going to - are we going to burn the PAD data that we got sometime ago, or is there a new maneuver coming up, or what's going on in that regard? [Pause.]
140:28:35 Mattingly: Okay, Apollo 8. If required, we'll give you a new one. Right now, we are looking at not making a maneuver burn at all.
140:28:46 Borman: You're saying we may not even have that one now?
140:28:48 Mattingly: That's right. [Long pause.]
140:29:04 Borman: Okay. You're the boss.
Comm break.
The following audio clip consists only of a series of unanswered calls to the spacecraft. As the spacecraft rolls in PTC, the omnis need to be constantly switched in order to maintain contact.
140:35:52 Mattingly: Okay. Read you loud and clear now. Just wanted to remind you that in the event of a loss of comm, we don't want you to burn MCC-7. Your present entry PAD is good. We'll be updating your landing point at the same time that you would have gotten MCC-7, and I'd like to have a crew status report from you when it's convenient. [Long pause.]
140:36:38 Borman: Okay, Ken. I understand now, if we would lose comm, you do not want us to burn MCC-7, just go ahead and use the entry PAD that you've given us?
140:36:46 Mattingly: That's affirmative. You'll be within 0.06 degrees of your entry angle target line.
In the end, there will be no MCC-7. Mission Control has slowly been arriving at this conclusion after continuing to track the spacecraft in its final hours leading up to Entry Interface. The ability to have reached the entry corridor with a single midcourse correction is a phenomenal tribute to the accuracy and reliability of the Flight Dynamics and Guidance teams, having been able to hit the narrow re-entry corridor all the way from the far side of the moon (TEI) with only one small tweak.
140:36:54 Borman: All right. The crew status is, everybody has gotten real good rest last night, and everybody's in good shape. Jim is just waking up, Bill's starting the initial stowage, and we're - we all feel very well.
140:37:12 Mattingly: Okay. [Pause.]
140:37:17 Mattingly: Okay. And we'd like to - guess we need a PRD reading from you. And we'll be needing one in the neighborhood of 145-hour period, somewhere when it's convenient in there again.
Long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
This is Apollo Control, Houston; 140 hours, 40 minutes into the flight and we just had a chat with the crew which was significant in two respects. They were advised that we would not have another midcourse. None was necessary. And we heard from Frank Borman that the crew is up now, and alert and awake, and Frank said they had a real good night's rest. And they are all set for the re-entry. Here's the conversation.
140:45:41 Mattingly: Apollo 8, Apollo 8, Houston. Go ahead.
140:45:45 Borman: Roger. Could you give us our range - correction, our velocity and range from the Earth now?
140:45:50 Mattingly: Stand by.
Comm break.
140:46:59 Mattingly: Apollo 8, Apollo 8, Houston. At time 51, your velocity will be 9,526, altitude 42,946. Over.
140:47:14 Borman: Thank you.
Very long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control, Houston here; 140 hours, 55 minutes into the flight. And before we get all wrapped up in the entry process, why don't we take a final look at our onboard system quantity readings? Our cabin pressure remains, as it has now for some days, at 4.9 pounds per square inch [33.8 kPa]; cabin temperature, 78 degrees [F, 26°C]. The amount of waste water on board right now is 69.5 percent of the tank capacity or 38.9 pounds [17.6 kg]. The potable drinking water quantity remains as it has throughout most of the mission at slightly over 100 percent, it is constantly being refilled from the fuel cell production. The potable quantity in pounds is 37.3 pounds [16.9 kg]. And the temperature of the water dump nozzle is 65 degrees Fahrenheit [18°C]. Now in the oxygen area, tank 1 has 59 percent of its oxygen supply remaining, tank 2 has 59.5 percent. And the hydrogen area; the number on tank 1 is 40.4 percent, tank 2, 42.5 percent. As we dial up further displays, we'll give you that information. And pilot biomed harnesses, we are not taking information right now apparently, (we) have turned that system down for the duration of the mission. And we're still searching here, stand by one. For your information, we're 42,293 [nautical] miles [78,327 km] away from Earth now, and velocity's built up to 9,600 feet per second [2,926 m/s]. To convert that to statute miles per hour, you multiply by 0.68. The oxygen flow is running at 0.3 pounds [0.14 kg] per hour. Point 3 pounds per hour. Fuel cell status: still load sharing very nicely. Fuel cell 1 carrying 33.1 percent; fuel cell 2, 32.2; fuel cell 3, about 34 percent; all very steady values, no problems at all on our fuel cells during the flight. And we have some conversation recorded from the crew, why don't we play that now.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
This is Apollo Control, Houston here at 141 hours, 29 minutes. It's been at least a half an hour since we've heard from the crew but no concern here. Things are very quiet obviously in the spacecraft. They're very quiet here in the Control Center. I suppose the two most active areas are the recovery forces. They're working very hard to ensure the adequacy of their communications circuits. They're running almost constant checks. And the retro people, who work very hard over this final entry-into-atmosphere maneuver. And all the members associated with it; they're working and comparing and talking to each other at a brisk pace. Other than that, it's all quiet at 141 hours and 30 minutes.
141:41:37 Mattingly: Okay. I've got some weather and recovery force status and a couple of last minute items to run down any time it's convenient for you.
141:41:47 Borman: All right. It's convenient right now.
141:41:50 Mattingly: Okay. For the mid-Pacific, the general condition is good. You can expect cloud bases 2,000 foot scattered, visibility 10 miles, wind 070 at 12, wave heights 4 feet, altimeter 2974. [Long pause.]
The Command Module has an altimeter that works in a similar way to a traditional aircraft altimeter by measuring the atmospheric pressure and displaying the result as an altitude. It is unclear whether this pressure reading of 29.74 inches is meant to allow adjustment of the altimeter given its coarse display. Expressing atmospheric pressure in inches is relatively archaic although it is still used in the United States. It comes from the use of a column of mercury in a glass tube to balance the weight of air above, a method of constructing early barometers. In much of the rest of the world, the unit to express atmospheric pressure is the millibar. One bar is about the same as normal atmospheric pressure, and standard atmospheric pressure is defined as 1013.25 millibars which is equivalent to 29.921 inches of mercury.
141:42:26 Mattingly: Okay, sunrise will be 17:10 Zulu, and first light, 16:49 Zulu. Recovery forces: ship will be Yorktown; the aircraft will be Airboss number 1 and 2, and Recoveries 1, 2, and 3. [Pause.] The estimated time to a target point: the ship is - Yorktown is on the target point; Airboss aircraft, 15 minutes and will be on-scene commander. Recoveries 1, 2, and 3 are SH3 Alphas, and they go with the Yorktown, so they're at the target point. All of them have swimmers aboard. If the recovery aircraft do not hear from the spacecraft, they'll go ahead and put swimmers in the water, and if you're in good shape and give them a call, they may hold off on dropping swimmers until sunrise.
141:43:45 Borman: Roger. Say again the sunrise and first light time for me, would you, please?
141:43:53 Mattingly: Say again, 8. [Long pause.]
141:44:23 Mattingly: Apollo 8, Houston. Notice the rather large middle gimbal angle. Over.
If the middle gimbal angle becomes too large, the gimbal system may become 'locked'; i.e. two of the three axes around which the gimbals turn will approach lining up. The nearer they get to each other, the more difficult it is to drive the motors that maintain platform alignment. There comes a point when the platform loses its intended alignment.
141:44:32 Borman: Thank you. [Pause.]
141:44:38 Borman: Would you say again the daylight time, please; sunrise, and first light.
141:44:44 Mattingly: Okay. Sunrise is 17:10 Zulu, and the first light is 16:49 Zulu. [Pause.]
141:45:01 Borman: Thank you.
Comm break.
141:46:05 Mattingly: Okay, 8. Looking over the weather I gave you was the 2,000 foot scattered at the target point. May have a 6,000 foot broken layer above that. At the max lift point, you have about the same thing, and altimeter's the same down the range. As you go further to the east, the weather should improve slightly; there's no problem with thunderstorms or rain showers in any of your recovery area.
141:46:42 Borman: Very good; thank you. [Pause.]
141:46:51 Mattingly: The items that we still need will be a PRD reading as late as you can do it conveniently prior to a final stowage. And we don't have any numbers on the last crew sleep period. I'd like to verify that the secondary RCS was activated on all four quads. And I have about five comments on the entry checklist procedures to verify.
141:47:24 Borman: It was activated on all four quads; that's correct. Our final stowage is completed. We'll read out the PR - we'll read out the PRDs for you now.
141:47:35 Mattingly: All right. Thank you.
141:47:40 Borman: The LMP's reads 0.64; I believe it's been that way throughout the flight. [Pause.] CMP's reads 0.11, that's 1.11.
141:47:58 Mattingly: Roger.
141:48:02 Borman: Stand by a minute while we look at it closely. That's 0.11.
141:48:09 Mattingly: Roger. 0.11.
141:48:13 Borman: And the one I ended up with reads 3.10.
141:48:37 Borman: Okay. Go ahead, Ken. What else do you want to talk about?
141:48:41 Mattingly: Okay. To make everybody happy, we can use an estimate of the number of hours sleep that people got.
141:48:50 Borman: Oh. Okay, sorry.
141:48:52 Borman: Just a minute, I'll give you that; I forgot.
141:48:55 Mattingly: Thank you.
141:48:57 Borman: Bill Anders got about 5 hours, [pause] and Jim Lovell got about five, and I got about five and a half or six.
141:49:09 Mattingly: Sounds good.
141:49:10 Borman: Right.
141:49:11 Mattingly: Okay. We went through an exercise with the mockup on the pre-entry preparations, and we noticed that in the LMP's checklist on page S-12, when you go to top off the repress bottles, I believe it's a misprint; it should read the PLSS fill valve rather than the Repress valve, and we should be going to the fill position as opposed to going to On.
141:49:47 Borman: Roger. That's what we do.
141:49:51 Mattingly: Okay. And on - go ahead. [Pause.]
141:50:01 Borman: Go ahead. We agree that's what we do.
141:50:04 Mattingly: Okay. On page E-7 of the entry checklist and under step 34, as long as you have panel 382 open, that's a convenient time to go ahead and have the evaporator water controls, both primary and secondary, to Auto, and the suit heat exchanger for the secondary glycol to Flow.
141:50:27 Borman: Those items are already accomplished.
141:50:27 Mattingly: Very good. On page E-9, when you're getting ready to transfer the RCS to the Command Module position, if you want to avoid having the engines fire as a result of attitude correction, you might want to take the manual attitude switches to Accel Command or Minimum Impulse. And again on E-9 Alpha at step 41 Bravo, if you want to go back to attitude hold, bring the manual attitude switches back to Rate. [Pause.]
141:51:13 Borman: What was that last step?
141:51:15 Mattingly: Step 41 Bravo on page E-9 Alpha. It's if you decide to use either Minimum Impulse or Accel Command on page E-9, step 41 Bravo would be a good place to go back to Rate Command.
141:51:31 Borman: Okay. We do - that's where we do it.
141:51:35 Mattingly: Okay, fine. And...
141:51:37 Borman: I don't...
141:51:39 Borman: I didn't put all those control configurations changes in the checklist, but that's exactly what we do, use Minimum Impulse.
141:51:47 Mattingly: Okay. Real fine.
Long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
This is Apollo Control, Houston, and everything seems to be proceeding very nicely. Ken Mattingly's been running through a entry - pre-entry checklist with Frank Borman. We're content, so are they. At the news conference a little while ago, numbers were passed to the press based on a final maneuver of something on the order of one or two feet per second. As you know, we scrubbed it, there is no need for such a maneuver, and has been terminated, but the fact that we are not going to have the maneuver matters almost not at all on the numbers. For instance, it changes the splash time by one second, so if you recorded numbers earlier, let's stick with those. And we have recorded the checklist conversation with Apollo 8, we'll play it for you now.
142:01:07 Mattingly: Apollo 8, Apollo 8. Go ahead.
142:01:11 Borman: I'd like to confirm one item on the PAD message, please.
142:01:15 Mattingly: Roger.
142:01:17 Borman: Time to retro the drogues, reference your last time to drogues, please.
142:01:28 Mattingly: Okay. I'll check that one out.
142:01:31 Borman: And also, Ken, we're going to turn on our VHF now, about 4 hours before entry.
142:01:37 Mattingly: Real fine. Thank you. I'll let you know when we pick it up.
142:01:41 Borman: A Simplex.
142:01:42 Mattingly: Affirm. [Pause.]
142:01:52 Anders: Ah, we're listening on VHF now too, Ken.
Very long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
This is Apollo Control, Houston at 142 hours, 3 minutes into the mission. A word or two on some of the congratulatory message traffic that we've experienced during this mission. I would call it unusually high. Probably associated with the general interest in the mission. The fact that it is the holiday season and more people have more time to express themselves. In general, far and away, the comments have been extremely laudatory, praiseworthy, and of course, there has, as there always is, a very small but an extremely vocal minority who thinks we shouldn't have done the mission or if we should have, we shouldn't have done it over religious holidays. Still others who have criticized any religious overtones that have crept into the mission. But perhaps, typical of the happier kinds of messages is one that was received here just a few hours ago simply from an anonymous well-wisher in Hornsby - H-O-R-N-S-B-Y, New South Wales, Australia. It reads, 'Happy landing Apollo 8 astronauts.' At 142 hours, 4 minutes into the flight; this is Apollo Control, Houston.
142:17:37 Mattingly: Okay. We have checked into your drogue time, and the number of 08:16 on your entry PAD is correct. We'll be giving you an updated entry PAD on the scheduled time of 143:30. At the same time, we'll be giving you an update of your state vectors for the LM and CSM.
142:18:01 Borman: Okay.
142:18:02 Mattingly: The midcourse correction number 7 was less than seven-tenths foot per second, and we will not execute it.
142:18:11 Borman: Very good.
142:18:12 Mattingly: You have a - You have a P52 scheduled at 143:30 which is not required. Your option. However, if you decide to delete the P52, the CMC self-check and DSKY condition light test are still requirements. Over.
142:18:32 Borman: What - what do you mean, they're still requirements? We weren't planning to do the CMC self-test. [Long pause.]
142:18:53 Borman: On that DSKY check, for goodness sake, that's...
Comm break.
Frank's tone, usually very dry and matter-of-fact, exhibits some impatience with what he's hearing.
142:51:31 Mattingly: Go ahead, Apollo 8. [No answer.]
142:51:45 Mattingly: Apollo 8, go ahead.
142:51:49 Anders: I'm just - It's my understanding we're going to bring up the secondary loop at 1 hour prior to Sep, is that right?
142:51:54 Mattingly: That's affirmative, about page Echo-9. [Pause.]
142:52:10 Anders: Okay. [Pause.]
142:52:16 Mattingly: And Bill, Rod suggested that if we have the water boiler going on the primary loop, that you - you might wait about 5 minutes or so before you initiate the secondary loop. [Pause.]
142:52:38 Anders: Wait 5 minutes from what? From the time the primary loop starts or from 1 hour?
142:52:43 Mattingly: From the time the primary loop starts; this'll give you a check to see if it had a chance to dry out or not. [Long pause.]
142:53:04 Anders: I'm with you. Okay.
142:53:09 Mattingly: And for your own information, we already have a VHF downlink. It's poor quality, but we do have contact.
142:53:22 Anders: Okay. We haven't turned anything over to VHF yet.
142:53:25 Mattingly: Okay.
142:53:27 Anders: We tried to call you on the VHF though, Ken.
142:53:30 Mattingly: Rog. I say, the quality's pretty poor; they may not be able to understand you.
142:57:01 Mattingly: Go ahead, Apollo 8. [No answer.]
142:57:14 Mattingly: Apollo 8, Houston. Go ahead.
142:57:17 Anders: Ken, we got two things going here which make this suit heat exchanger flow a little different. One of them is we're not doing a cold-soak, and the other one is we're powering down the secondary loop prior to Sep. And I wonder if it's a good idea to have the suit heat exchanger only on a secondary loop in that case. And plus the fact that we haven't got any cabin heat exchanger.
142:57:45 Mattingly: I don't think that was the intent, Bill. What they had in mind, we'd have both loops - have the suit heat exchanger on both loops; and if they got too cold, you could use the panel switching to shut down the primary loop through the heat exchanger. But in any event, you'd always have something going to the suit heat exchanger. I recognize that we are going to be shutting down the secondary heat exchanger pre-Sep and then turning it back on prior to entry, but the idea was to have both primary and secondary loops on the suit heat exchanger simultaneously.
142:58:24 Anders: Yeah, my checklist doesn't reflect that, but I think that's a good idea since we're a little suspect of our cabin fans and don't plan to use them.
142:58:31 Mattingly: Rog.
Long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control, Houston here; 142 hours, 59 minutes into the flight. And the velocity increase we're seeing is now becoming dramatic. We're up to 11,298 feet per second [3,444 m/s] and it's really building. We're at 30,424 [nautical] miles [56,345 km] from home. Here's the conversation with the crew.
143:02:08 Mattingly: Apollo 8, Apollo 8. Go ahead.
143:02:12 Anders: Roger. What's Rod's estimate of our post-separation main bus voltage?
Very long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control, Houston here. That brings us up to date. And to amplify one remark I think you heard Bill Anders say, he'd try to call on VHF. If it was received, it was badly garbled. If I recall correctly, on the way out, and they're quite a way from the Earth, we - they heard us broadcasting on VHF out to about 22,000 [nautical] miles [41,000 km]. They've got just about the reverse situation here where it's slightly more than 29,000 [nautical] miles [54,000 km] out. At 143 hours, 4 minutes into the flight, this is Apollo Control, Houston.
143:16:24 Anders: I'm still a little bit confused on this - activate the secondary loop. You indicated in - activating it at 1 hour or 5 minutes after the primary evaporator comes on the line. My checklist shows that the primary evaporator probably won't come on the line until we bypass the radiators. Have you got something else in mind that I don't know about? [Pause.]
143:16:56 Mattingly: Okay, Bill. We passed up an update some time back on page E-9, step 38, right at the beginning; and you've got a final GDC drift check. And then between there and the - and the step 39 where it says to terminate CM RCS preheat, that was the place we wanted to activate the primary loop by putting the glycol evaporator water switch to Auto and the glycol evaporator steam pressure to Auto. [Long pause.]
143:17:41 Anders: Roger. I don't expect it to boil, though. Do you?
143:17:45 Mattingly: Okay, Bill. We're hoping that it will there. It looks like we'll have had a stable attitude for some time, and we anticipate that it will be warm enough to make it boil. That is the reason it's suggested if it is boiling, that you wait. If it isn't, go ahead and turn on the secondary loop.
143:18:04 Anders: Okay. Well, that's where I was confused. I'm waking up. Thank you.
143:20:11 Mattingly: Okay, Apollo 8. We'd like to update your LM state vector, CSM state vector, and target point. And if it's convenient now, why, we'll go ahead and do that if you'll go to P00 and Accept. [Pause.]
143:29:25 Mattingly: Okay. The loads are in and verified, and the computer is yours.
143:29:29 Anders: Thank you.
143:29:30 Mattingly: You can take it back to Block, and for Bill's information, latest guess on the main bus post-Sep voltage to 27.5 [volts].
143:29:41 Anders: Guess?! [Pause.] You mean the EECOMs are guessing? [Pause.]
143:29:57 Anders: At least, they're honest for a change.
143:30:02 Mattingly: That's more than you can say for the computers.
143:30:06 Anders: Or the crew.
Long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control, Houston here at 143 hours, 36 minutes into the flight. And we've been chatting more with Bill Anders primarily on how things look. The spacecraft is now 26,458 [nautical] miles from Earth [49,000 km], moving in a velocity of 12,075 feet per second [3,680 m/s]. The weight of the spacecraft is 31,600 pounds [14,300 kg]. Now that weight will change dramatically 15 minutes before we reach the 400,000-foot mark when the Service Module leaves us and it will go from 31,600 down to about 12,000 pounds [5,400 kg] and will hold close to that on in. Here's the conversation.
143:36:40 Mattingly: Apollo 8, Houston. [No answer.]
143:37:00 Mattingly: Apollo 8, Houston.
143:37:03 Borman: Go ahead, Houston. Apollo 8.
143:37:05 Mattingly: Okay, 8. We have an entry PAD for you.
143:37:10 Borman: Good! Just a minute. [Long pause.]
143:37:33 Anders: Ready to copy, Houston.
143:37:38 Mattingly: Okay. This will be the mid-Pacific; 357, 152, 359; 146:29:00; 268, plus 08.13, minus 165.03; 06.5, 36221, 6.45, 1212.2, 36301, 146:46:14, 00:28. The next block is November Alpha: DO 4.00, 02:12; 00:25, 03:34, 08:14; 16, 059.0, 31.2; Zeta Persei, up 16.5, right 3.4; up. Use non-exit EMS pattern, GDC Align; primary star Sirius, secondary Rigel; roll, 308; pitch, 209; yaw, 357. This entry will not involve P65. Over. [Pause.]
143:40:25 Lovell: Houston, Apollo 8. Entry PAD as follows: mid-Pacific; 357, 152, 359; 146:29:00; 268, plus 08.13, minus 165.03; 06.5; 36221, 6.45, 1212.2, 36301, 146:46:14, 00:28, next block not applicable, 4.00, 02:12; 00:25, 03:34, 08:14; 16, 059, 31.2; Zeta Persei, up 16.5, right 3.5, up. Use non-exit EMS pattern, backup alignment; Sirius, Rigel; roll, 308; pitch, 209; yaw, 357; and we won't see P65.
143:41:37 Mattingly: Okay, Apollo 8. I'd like to verify sextant star shaft 0590, and the boresight star.
143:41:49 Lovell: Roger.
143:41:50 Mattingly: The last one is right 3.4. Over.
143:41:56 Lovell: Roger. Boresight star is right 3.4. And I have the sextant shaft; that's 059.0.
143:42:03 Mattingly: That's correct, Apollo 8.
Very long comm break.
This entry PAD is preliminary and will be updated in 90 minutes time. As with all PADs, there is a very strict format associated with it. Both astronauts on the ground and in the spacecraft are using a form that contains all the necessary details for interpreting the numbers.
Form for the Entry PAD, page E-4 of the Entry checklist.
Before interpreting the PAD, it may be useful to explain some of the terminology used. The first important concept is that of Entry Interface, a completely arbitrary event which is defined as the time when the spacecraft (then consisting of only the Command Module) reaches an altitude of 400,000 feet (65.83 nautical miles, 121.92 km). Being arbitrary, it is not subject to the vagaries of the atmosphere and allows calculations to be made with respect to the spacecraft's current state vector.
A second concept is the 0.05g event. This is the point at which the increasing drag of the atmosphere's outer fringes cause a deceleration measuring a twentieth of a g. For calculation sake, prior to entry actually occurring, it is taken to occur at an altitude of 297,432 feet (48.95 nautical miles, 90.66 km) but it will occur when the spacecraft's guidance system detects a change in velocity of 0.49 m/s2 (0.05g). This detection triggers a change in the entry program run by the computer and also begins the monitoring of the trajectory by the EMS (Entry Monitoring System).
Note that some events in the PAD are tied to the Entry Interface event, others to the 0.05g event. The data passed up for this entry PAD are interpreted as follows:
Purpose: Entry.
Landing target: The landing target is in the Mid-Pacific.
IMU gimbal angles required for trim at 0.05g: Roll, 357°; pitch, 152°; yaw, 359°.
Time of the horizon check: 146 hours, 29 minutes, zero seconds GET.
Spacecraft pitch at horizon check: 268°. This is 17 minutes before time of entry.
Splashdown point: 8.13° north latitude, 165.03° west longitude.
Entry flight path angle at Entry Interface: 6.45°. This is very close to the angle they are aiming for, 6.5°.
Range to go to splashdown point from 0.05g event: 1,212.2 nautical miles. To set up their EMS (Entry Monitor System) before re-entry, the crew need to know the expected distance the CM would travel from the 0.05 g event to landing. This figure will be decremented by the EMS based on signals from its own accelerometer.
Predicted inertial velocity at 0.05g event: 36,301 feet/second. This is another entry for the EMS. It is entered into the unit's Delta-V counter and will be decremented based on signals from its own accelerometer.
Time of Entry Interface: 146 hours, 46 minutes, 14 seconds GET.
Time from Entry Interface to 0.05g event: 0:28 (seconds).
The next four items are not applicable to this version of the Entry PAD as they are only concerned with flight path profiles that exit the atmosphere for a short period.
Planned drag level (deceleration) during the constant g phase: 4.00g.
Time to VCIRC: 2:12. This is the time from Entry Interface to when their velocity has slowed sufficiently to allow a circular orbit around the Earth. The practical implication of this is that this is the "capture point" where the CM will no longer be able to skip off the atmosphere. Since the spacecraft will already be within the Earth's sensible atmosphere at this point, drag will continue to slow the spacecraft and the return to Earth is assured.
Time from Entry Interface that the communications blackout begins: 0:25.
Time from Entry Interface that the communications blackout ends: 3:34.
Time from Entry Interface that the drogue parachutes will deploy: 8:14.
Sextant star: 16 (Procyon, Alpha Canis Minoris.)
Sextant shaft angle at Entry Interface minus 2 minutes: 59.0°.
Sextant trunnion angle at Entry Interface minus 2 minutes: 31.2°.
Boresight star: Zeta Persei. This is an attitude check made using the COAS sighted on a star two minutes before Entry Interface.
Boresight Star pitch angle on COAS: Up 16.5°.
Boresight Star X position on COAS: Right 3.4°.
Lift vector at Entry Interface: Up.
The PAD includes a comment about which part of the EMS scroll to use. The EMS scroll has multiple patterns, one each for the two different types of entries the spacecraft can make. Apollo 8 is to use the version suited to their non-exiting type of re-entry.
GDC Align stars: Stars to be used for GDC Align purposes are Sirius and Rigel. If the primary guidance system fails, it cannot be used to align the GDCs, which provide a backup attitude reference. Another means of aligning the GDCs per the REFSMMAT is to view these stars through the telescope until they are aligned with the graticule or reticle in a known way. The spacecraft's attitude, with respect to the REFSMMAT, would then be as given by a stated set of angles. These are dialled in via a set of thumbwheels to provide a starting point for the GDCs.
The final note reiterates that this will not be an exiting re-entry since P65 controls the start of that exit and is not being used.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control here, and that brings us up to the point where we are now. For those newsmen watching the projection on monitors in our MSC Auditorium news area, you'll be able to see very shortly the spacecraft do a long loop-the-loop kind of maneuver against a flat map such as we're viewing. The maneuver will be quite similar to that that we saw the other day after the TLI burn when we did a big loop before we started tracing a steady flight path away from the Earth. Of course, we are going to see this morning the mirror image of that maneuver, only in this case it will be performed almost directly over India. The spacecraft is now looking down on the southern tip of India. It's directly over Ceylon [now Sri lanka], and it will, for Earth-mapping purposes, seem to proceed in a northwesterly direction. As it prepares to make its entry, as it lines up for its entry path back to the Earth and the Pacific Ocean. We're 25,309 [nautical] miles [46,872 km] away from the spacecraft and it is moving at 12,328 feet per second [3,758 m/s]. At 143 hours, 47 minutes; this is Apollo Control, Houston.
143:59:37 Mattingly: Apollo 8, Houston. [No answer.]
143:59:50 Mattingly: Apollo 8, Apollo 8, Houston.
143:59:56 Lovell: Go ahead, Houston.
143:59:58 Mattingly: Okay, Apollo 8. Can you tell us if you've done anything with your potable water? We've noticed our readout has gone from 100 percent down to 56 in the last couple of minutes. [Pause.]
144:00:17 Lovell: We're reading about 50 percent right now.
144:00:22 Mattingly: Roger. That correlates with what we see. Have you done anything to change configuration? Over. [Long pause.]
144:04:58 Mattingly: Apollo 8, Apollo 8, go ahead.
144:05:01 Lovell: Roger, Houston. We're still showing about 52 percent here, and we had our switch on waste so we don't know whether it dropped from a higher value or not. Has yours been stabilized now?
144:05:15 Mattingly: That's affirmative; ours has stabilized now. And it was reading full just a few minutes ago.
144:05:25 Lovell: Roger. I don't think - we can't account for any sudden drop in water.
144:05:31 Mattingly: Okay. We looked in the malfunction procedures, in number 28. And [it] doesn't reveal anything very startling.
144:05:42 Lovell: Bill's looking there now.
Long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
This is Apollo Control, Houston; 144 hours, 8 minutes into the flight. And things are continuing to rock along. We're - In the last few minutes, we had a little surprise here with a not-yet-completely-explained water dump. We chatted with the crew about it and, apparently, Bill Anders had dumped some waste matter, some urine overboard earlier, which had collected for a while. We still don't completely understand it. We're talking a little about this and here's how the conversation goes.
144:09:00 Anders: Okay. I'm looking at malfunction 28, and it takes you to box 6, but I don't really think that's the problem because the waste tank quantity hadn't changed any. Over.
144:09:11 Mattingly: Okay. I concur. We're watching the same thing.
144:09:15 Anders: Look, we don't care about the potable tank, but we do about the waste tank, so I'm just gonna - just in case there is a problem somewhere, I'm going to shut the potable tank off and leave the waste tank inlet valve open. How's that sound to you?
144:09:29 Mattingly: Stand by. [Pause.] Okay, 8. We concur.
144:09:37 Anders: If I see any water floating around, I'll give you another call.
144:09:40 Mattingly: Alright. Thank you.
Long comm break.
At this point, communications are temporarily lost due to a problem linking Houston to the tracking station at Carnarvon. The following audio file (not reflected in the transcript) contains sporadic communication between the Network flight controller and Carnarvon as they attempt to reconnect.
[Download MP3 audio file of . Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
As Apollo 8 reaches lower altitudes, the three main tracking stations (Honeysuckle, Goldstone and Madrid) can no longer provide continuous coverage. In addition, as the spacecraft speeds up, it "catches up" with the Earth's rate of rotation and its ground track does a loop from westbound to eastbound, passing westward across Australia, northward through India, and then eastward across China and the Pacific, heading towards splashdown. As a result, spacecraft communication will pass through Carnarvon and thence to Guam, the Pacific-based tracking ships Redstone (at 24°N, 169°E), Huntsville (at 12°N, 173°W), the aircraft-based ARIA, and eventually the recovery forces themselves (at 8°N, 165°E).
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
So much for our water situation. It's apparently been laid to rest now. As Anders said, not - not really a problem. Just not immediately explainable so he turned off the potable tank. There are two tanks here; a potable tank - the drinking water, and the waste water tank. He had vented the waste water tank to some degree but apparently had not - they saw some kind of action on the potable meters. In any case, it's been adjusted. Our present distance; 22,276 nautical miles [41,255 km] from Earth. This puts the spacecraft at the synchronous orbital altitude and it will now begin to sink its direction in relation to our lunar map. In other words, it'll start flying in the direction of the turn of the Earth. Or, at least, it will appear to us down here on Earth to do that. The spacecraft, in fact, is a fixed point in inertial space, just as the Earth is. But for mapping purposes, it will appear to turn from approximately this point forward. Our velocity's 13,102 feet per second [3,993 m/s]. At 144 hours, 13 minutes; this is Apollo Control, Houston.
144:18:30 Mattingly: Apollo 8, Houston. Radio check. [No answer.]
144:18:47 Mattingly: Apollo 8, Apollo 8. Radio check.
144:18:51 Lovell: Read you loud and clear.
144:18:53 Mattingly: Roger. We had a momentary loss of comm on the ground then. Read you loud and clear.
Long comm break.
During the pause, Carnarvon and Houston continue to struggle to maintain communication with each other (and hence to the spacecraft). The following clip records this exchange.
144:27:13 Borman: Houston, Apollo 8. Did you call?
144:27:17 Mattingly: Apollo 8, Houston. You're loud and clear. We've taken a look at this water...
144:27:23 Borman: Houston, Apollo 8.
144:27:27 Mattingly: Apollo 8, Apollo 8, Houston. Read you loud and clear. We've taken a look at your potable water quantity problem, and it appears to be a transducer problem. Suggest that you leave the potable tank isolated. You have sufficient water in the waste tank to continue the entry. Over.
144:32:03 Borman: Houston, how do you read? Apollo 8.
144:32:06 Mattingly: Read you loud and clear, Apollo 8, and we're checking on the PTC problem now. [Pause.]
144:32:19 Mattingly: Apollo 8: Houston. You're cleared with entry attitude at this time.
144:32:23 Borman: Okay. Fine. Thank you.
Very long comm break.
The spacecraft is sufficiently near to the time of Service Module jettison that the Passive Thermal Control is no longer required. Frank is eager to stay ahead of the timeline as much as possible and is now cleared to maneuver to entry attitude.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control, Houston here at 144 hours, 38 minutes into the flight. Apollo 8 is 19,000 [nautical] miles [35,188 km] from the Earth; it's moving at 14,029 feet per second [4,276 m/s]. Present combined weight of the Command Module and Service Module: 31,600 pounds [14,300 kg]. We have some conversation - we've had some conversation. Let's hear it now.
144:46:22 Houston Comm Tech: Houston voice. Go to voice 425.
Very long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control here, that brings us up to date. We look good all across the board. People - the Control Center is beginning to fill up now with official observers, officials of the program. The 70-seat viewing-room immediately behind this Control Center is about half-filled right now, and within the next hour, I imagine we will see it filled to overflowing, which it's been during every critical event of this mission. At 144 hours, 41 minutes; this is Apollo Control, Houston.
144:58:28 Network: Carnarvon, Network. GOSS conference voice check. How do you read?
144:58:36 Carnarvon Comm Tech: Network, Carnarvon. Read you weak but clear.
144:58:41 Network: Roger, Carnarvon. I read you loud and clear.
144:58:44 Carnarvon Comm Tech: You're loud and clear now. Thank you.
144:58:57 Mattingly: Apollo 8, Houston. Stand by for hand over to Carnarvon.
144:59:02 Anders: Roger.
Comm break.
Bill seems to be having fun as he mimics the plummy accents of the Australian communications technicians whose voices have found their way onto the air/ground loop.
145:06:18 Mattingly: Apollo 8, Houston. State vector load is complete. Verify the computer is yours. [Long pause.]
145:06:35 Mattingly: Apollo 8, Apollo 8, Houston. State vector load is complete; the computer is yours. [Pause.]
145:06:47 Borman: Roger, Houston. We're going to Block.
145:06:50 Mattingly: Roger.
Long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control, Houston here. And the spacecraft is now a mere 15,256 [nautical] miles [28,254 km] from the face of the Earth. Its velocity is almost a match in feet per second; 15,459 feet per second [4,712 m/s]. Its weight; 31,600 pounds [14,300 kg]. The Service Module, or approximately 20,000 of those pounds [9,000 kg] will be jettisoned abruptly at 15 minutes before we reach the 80-mile high, the 400K, 400,000-foot mark. At - one other mention, the viewing room as we've said earlier is beginning to fill with visitors and among them is Dr. Kurt Debus, director of the Kennedy Space Center, and his number one deputy for launch operations, Rocco Petrone, two gentleman who had so much to do with the departure of Apollo 8 from the - six mornings - six days ago. They're here to watch it come back to Earth this morning. At 145 hours, 09 minutes into the flight; this is Apollo Control, Houston.
145:11:00 Mattingly: Okay. Two fast items: number one, it's been suggested that since Marezine takes some time to take effect, you might consider whether you'd be interested in taking some now. And I have an entry PAD which has some very small updates to go on it if you would like to copy that.
145:11:22 Borman: Okay. Stand by, and we'll get out the entry PAD. [Long pause.]
145:11:38 Lovell: Okay. Go ahead with the entry PAD, Houston.
145:11:42 Mattingly: Okay. We're still going to the mid-Pacific; 357, 152, 359; 146:29:13, 267; plus 08.13, minus 165.03; 06.6; 36221, 6.47; 1216.6, 36301; 146:46:13; 00:28; the next block is November Alpha; D0 4.00, 02:10; 00:25, 03:35, 08:16; 16, 059.0, 31.2; Zeta Persei, up 16.5, right 34; up. Non-exit EMS pattern; Sirius and Rigel: roll, 308; pitch, 209; yaw, 357. No P65 involved. Over. [Long pause.]
145:14:11 Lovell: Roger, Houston. Entry PAD as follows: mid-Pacific, 357, 152, 359; 146:29:13, 267; plus 08.13, minus 165.03; 06.6; 36221, 6.47; 1216.6, 36301; 146:46:13; 00:28; N/A; 4.00, 02:10; 00:25, 03:35, 08:16; 16, 059.0, 31.2; Zeta Persei, up 16.5, right 3.4; up. Use non-exit EMS pattern; Sirius, Rigel, 308, 209, 357, no P65.
145:15:11 Mattingly: That's correct, Apollo 8. [Long pause.]
This is the final entry PAD for Apollo 8. It is interpreted as follows:
Purpose: Entry.
Landing target: The landing target is in the Mid-Pacific.
IMU gimbal angles required for trim at 0.05g: Roll, 357°; pitch, 152°; yaw, 359°.
Time of the horizon check: 146 hours, 29 minutes, 13 seconds GET.
Spacecraft pitch at horizon check: 267°. This is 17 minutes before time of entry.
Splashdown point: 8.13° north latitude, 165.03° west longitude.
Entry flight path angle at Entry Interface: 6.47°. This is even closer to the angle they are aiming for, 6.5° than in the preliminary PAD.
Range to go to splashdown point from 0.05g event: 1,216.6 nautical miles. To set up their EMS (Entry Monitor System) before re-entry, the crew need to know the expected distance the CM would travel from the 0.05 g event to landing. This figure will be decremented by the EMS based on signals from its own accelerometer.
Predicted inertial velocity at 0.05g event: 36,301 feet/second. This is another entry for the EMS. It is entered into the unit's Delta-V counter and will be decremented based on signals from its own accelerometer.
Time of Entry Interface: 146 hours, 46 minutes, 13 seconds GET.
Time from Entry Interface to 0.05g event: 0:28 (seconds).
The next four items are not applicable to this version of the Entry PAD as they are only concerned with profiles that exit the atmosphere for a short period.
Planned drag level (deceleration) during the constant g phase: 4.00g.
Time to VCIRC: 2:10. This is the time from Entry Interface to when their velocity has slowed sufficiently to allow a circular orbit around the Earth. The practical implication of this is that this is the "capture point" where the CM will no longer be able to skip off the atmosphere. Since the spacecraft will already be within the Earth's sensible atmosphere at this point, drag will continue to slow the spacecraft and the return to Earth is assured.
Time from Entry Interface that the communications blackout begins: 0:25.
Time from Entry Interface that the communications blackout ends: 3:35.
Time from Entry Interface that the drogue parachutes will deploy: 8:16.
Sextant star: 16 (Procyon, Alpha Canis Minoris.)
Sextant shaft angle at Entry Interface minus 2 minutes: 59.0°.
Sextant trunnion angle at Entry Interface minus 2 minutes: 31.2°.
Boresight star: Zeta Persei. This is an attitude check made using the COAS sighted on a star two minutes before Entry Interface.
Boresight Star pitch angle on COAS: Up 16.5°.
Boresight Star X position on COAS: Right 3.4°.
Lift vector at Entry Interface: Up.
The subsequent notes are the same as for the preliminary PAD. Apollo 8 is to use the EMS scroll pattern suited to their non-exiting type of re-entry.
GDC Align stars: Stars to be used for GDC Align purposes are Sirius and Rigel.
145:23:19 Anders: Okay. It doesn't appear that we are going to be able to trigger the primary evaps, so I'm going to go ahead and start up the secondary loop. [Pause.]
145:26:58 Mattingly: Apollo 8, Apollo 8, go ahead.
145:27:01 Borman: Roger. Since we're going as smoothly as we are here, we've got good comm, let's start this pyro circuit check about 10 minutes early. What do you say? [Long pause.]
145:27:25 Mattingly: Apollo 8, Apollo 8. We can conduct the pyro check at any time.
145:27:31 Borman: Alright. Why don't we do it here just momentarily then?
145:27:36 Mattingly: Roger.
145:27:38 Borman: We'll give you a call when we're ready.
145:27:40 Mattingly: Roger. [Long pause.]
145:27:58 Borman: Houston, we're ready to proceed with the pyro circuit check.
145:31:07 Borman: MSFN, are you monitoring the sequential test now? [Pause.]
145:31:15 Borman: Houston, Apollo 8. [Pause.]
145:31:23 Mattingly: Apollo 8, Apollo 8. That's affirmative. [Long pause.]
145:31:38 Borman: Hello, Houston. Apollo 8.
145:31:43 Mattingly: Apollo 8, Apollo 8. Loud and clear. Affirmative we are monitoring.
145:31:48 Borman: Okay. [Long pause.]
145:32:07 Anders: Standing by for Go for Pyro Arm.
145:32:13 Mattingly: Apollo 8, Apollo 8. You have a Go.
145:32:17 Anders: Roger.
Long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control, Houston here at 145 hours, 32 minutes into the flight, and the trajectory of Apollo 8 is programmed against the - our flat wall map here is carrying it on a path up the west coast of India. It will proceed northerly - northeasterly in a very few moments, and curve, and start in an easterly direction carrying it across China, perhaps before then it will see a little of the southern extremities of the Soviet Union, the Himalayas, China and then down across Guam. Present velocity is 17,272 feet per second [5,265 m/s]; the spacecraft is only 11,626 [nautical] miles [21,531 km] from the face of the Earth. A few minutes ago, Frank Borman called us and suggested we might entertain doing the pyro arm check a little early. It was considered here, we quite agree with him and we're all set to go on it. Here's how the conversation went.
145:41:41 Borman: Houston, this is Apollo 8; How's your tracking looking?
145:41:47 Mattingly: Looking great.
145:41:50 Borman: Okay. Everything went fine with the check. We're all armed and ready to go here.
145:41:55 Mattingly: Okay. If you're not doing anything else, how about let's make a VHF check.
145:42:02 Borman: Okay. I'll turn off my S-band; the other two will stay on S-band.
145:42:06 Mattingly: Roger. I'll give you a count in just a second. [Long pause.]
145:42:30 Mattingly: Apollo 8, Houston. Simultaneous VHF and S-band. Over.
145:42:37 Borman: Rog. I'm not reading you on VHF.
145:42:40 Mattingly: Rog. Stand by one. [Long pause.]
145:43:31 Mattingly: Apollo 8, Houston. Simultaneous VHF and S-band. Do you verify that you are on the left hand VHF antenna? Over. [Pause.]
145:43:48 Borman: We can verify the antenna, but we can't verify reading you on S-band or on VHF.
145:43:54 Mattingly: Okay. We're receiving some downlink, although it's considered to be poor quality.
Long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control, Houston here at 145 hours, 45 minutes into the flight. And all is continues to operate quite satisfactorily. We tried a VHF check with the spacecraft a few minutes ago. It didn't work out so well. Neither Carnarvon nor Guam picked up on VHF; that from about 10,000 miles out. We're now 9,600 [nautical] miles [17,800 km] from the Earth. The velocity is up to 18,532 feet per second [5,649 m/s]. And we have a little conversation backed up on us, let's hear it now.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control here. Some may be wondering what happens to the Service Module. Well, it's jettisoned at 15 minutes before we reach our Entry Interface or entry point. And there's a preset burn of 90 feet per second [27 m/s] cranked into the Service Module. It departs from the Command Module at that rate. The burn continues for some period of time, exactly which period, I don't have in front of me; but at any case, the new trajectory of the Service Module carries it about 100 miles or more south of the track of the Command Module. It's not known exactly what will happen to the Service Module. Some people think it will come on down to an altitude of perhaps 300,000 or 400,000 feet, hit the thicker atmosphere and then bounce out into a sun-circling orbit. Others think it will be captured and will certainly burn up before any of its pieces reach the Pacific Ocean. We just can't predict at this point. We are certain it will be safely out of the way of Apollo 8. At 145 hours, 48 minutes; this is Apollo Control, Houston.
145:57:21 Mattingly: Apollo 8, Houston. Stand by for handover from Carnarvon to Guam on the hour. We should have continuous contact except for the blackout period beginning at 146:51.
145:57:36 Borman: Roger.
Very long comm break.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
This is Apollo Control, Houston at 146 hours, 12 minutes into the flight. I think all the consoles here have been reconfigured for this re-entry effort now. Probably the most noticeable item, leaving the consoles, are the lunar maps. They're being replaced by maps which rested right under the lunar maps, which were simply projections of good old Earth. A few minutes ago, the crew checked some of the events that will take place in the re-entry process and here's what we passed them.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
Apollo Control here. And now the velocity acceleration pickup is quite dramatic. Our display here integrates a new value every 12 seconds, I believe. Let me give you a sample of how it is building; 23,303 feet per second [7,103 m/s] right now; altitude, 4,950 [nautical] miles [9,167 km]. Still reading 23,353, 23,403. It's been stepping up here in these last few minutes in increments of 50 to 60 feet per second. For reference purposes, the peak velocity previously reached prior to this mission by a manned vehicle was the Gemini 11 spacecraft, at perigee after its high altitude burn, which was the other two altitude record as well, 740-odd miles. But that velocity was 26,352 feet per second [8,032 m/s]. Today, we should, at the point of Entry Interface or the 80-mile mark, as we come back into the Earth, we should see a velocity on the order of 36,220 feet per second [11,040 m/s]. Converted to miles per hour, that is 24,530 miles per hour. And at 146 hours, 16 minutes into the flight; that's our status and this is Apollo Control, Houston.
[Download MP3 audio file of PAO announcer recording. Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.]
PAO release line test. 1 2 3 4 5 - 5 4 3 2 1 - the quick brown fox jumps over the lazy dog's back. Test out.
