Apollo Flight Journal logo
Previous Index Next
Day 1, part 6: Housekeeping and TV transmission Journal Home Page Day 2, part 8: Mid course correction and TV transmission

Apollo 10

Day 1, part 7: PTC concerns and sleep

Corrected Transcript and Commentary Copyright © 2009-2022 by W. David Woods, Robin Wheeler and Ian Roberts. All rights reserved.
Last updated 2022-08-01
This is Apollo Control. It appears that we'll have no further conversation with the crew at this time. They either are, or will shortly be in their rest period. Tom Stafford advised about 15 minutes ago, that Gene Cernan, had begun a rest period, under the right hand couch, and reported at that time, that he and John Young were also beginning their sleep period shortly. Apollo 10 is now 54,487 nautical miles [100,909 km] from Earth, traveling at a speed of 8,000 feet per second [2,440 metres per second]. We just had a call from the spacecraft.
011:04:39 Stafford: Hello, Houston, Apollo 10.
011:04:42 Engle: Roger, Tom. Go ahead.
011:04:44 Stafford: Roger. What's the - the latest consensus on that chlorination?
011:04:48 Engle: Oh, I'm sorry. I thought - thought we'd passed that on. I'm afraid we got to do that, Tom. As per agreement with the doctors.
011:04:58 Stafford: All right.
011:05:02 Stafford: Hey, how about checking...
011:05:03 Engle: Hey...
011:05:06 Engle: Go ahead.
011:05:08 Stafford: Yes, there was supposed to be some agreement that if the water was serviced right and we lifted off on time, we wouldn't have to do it for a day or two.
011:05:16 Engle: Yes, I know. We've already - already wrestled that one out, and we lost on that.
011:05:24 Stafford: Okay.
011:15:06 Stafford: Hello. Houston, Apollo l0.
011:15:08 Engle: Roger. Go ahead, Tom.
011:15:10 Stafford: Okay. We've put in the chlorine, just shot the buffer to it. Now do you want the potable tank inlet valve Open? It's been isolated all this time; do you want it Open?
011:15:20 Engle: Negative. We want to leave it Closed, Tom, until tomorrow.
011:15:26 Stafford: So you want to have some really good chlorinated water, then, right?
011:15:29 Engle: Boy, I'm afraid so. We've been wrestling that one out, but it looks like we've got to put it in again.
From the Apollo 10 Mission Report, August 1969: - The waste stowage vent valve was closed at 10.5 hours, and in two hours the oxygen flow decreased from 0.7 to 0.2 lb/hr. Prior to the first sleep period, the crew was instructed by the ground to service the potable water system with chlorine while the potable tank inlet valve was closed. The crew twice requested clarification of this procedure, since it was contrary to the normal procedure. With this valve closed, it appeared the chlorine would not circulate into the potable tank. Upon awakening, the crew soon discovered by taste that the potable water lines were full of chlorine and the valve should have been opened, as originally suspected.
011:15:34 Stafford: All right.
011:15:35 Engle: I know what you mean.
011:15:38 Young: Okay. But you - you just want to leave it Closed, right?
011:15:41 Engle: That's right, John.
011:15:43 Young: Okay.
011:22:14 Stafford: Hello, Houston, Apollo 10.
011:22:17 Engle: Roger, 10. Go ahead.
011:22:19 Stafford: Okay. I'm about to finish that ... thing, and we're going to sack out. And I've got the duty for the night and the sleeping bag up in the left seat so if anything comes up, give me a call.
011:22:29 Engle: Okay, Tom. We sure will. Have a good night's sleep. We got a lot of eyes looking down here.
011:22:35 Stafford: Okay.
011:22:42 Engle: I guess in - in discussing this chlorination thing, Tom, if we get through this first one, why that's the worst one; we get on the schedule then, the 24-hour schedule where you - you give it the chlorine in the evening, and it has time to dissipate by morning, by the time you wake up.
011:22:58 Stafford: Yes, the only question I want to know is we had a brand new load of water; it was completely isolated and plain when they put it on board the spacecraft, then why did we have to give it another shot?
011:23:08 Engle: Well, it - It turns out that I guess they feel that the chlorine becomes pretty inactive as far as killing bacteria in about a 24-hour period, and when we chlorinated this morning, if we were to wait to get on this schedule where you chlorinate in the evening, which is really the best time, because that you get - you drink your water and then you chlorinate and it has time to dissipate during the sleep cycle. Then by morning it isn't quite so had, and in order to get on that cycle, we had to do it tonight.
011:23:37 Stafford: Okay.
The CDR (Stafford) will sleep in the right couch during the first night, wearing a headset in case voice communications are necessary, whilst CMP (Young) and LMP (Cernan) sleep in restraints below the left and right couches.
Sleep restraint
This is Apollo Control at 11 hours 25 minutes. We've just been advised by Tom Stafford that he and John Young are now beginning their rest period. Stafford also advised that he had chlorinated the onboard water supply. We'll play that tape back for you now.
It appears that Stafford and Young will be beginning their sleep period at about 11 hours, 30 minutes Ground Elapsed Time and that's about an hour and a half ahead of the original Flight Plan schedule and Stafford reported about 35 or 40 minutes ego that Gene Cernan had already begun him rest period under the right-hand couch. Young and Cernan resting in the sleep stations under the right end left hand couches with Cernan under the right hand couch and Young under the left hand couch and Tom Stafford as you heard will have the duty tonight and will be sleeping in the sleeping bag on the left hand couch. At 11 hours, 29 minutes into the flight, Apollo 10 now 56,372 nautical miles [104,400 km] from Earth and traveling at a speed of 7,908 feet per second [2,411 metres per second]. This is Mission Control, Houston.
Flight Plan page 3-13.
This is Apollo Control at 12 hours, 17 minutes. We've had no conversation with the spacecraft since our last report. Tom Stafford reported at 11 hours, 30 minutes Ground Elapse Time, about 47 minutes ago, that he and John Young would join Gene Cernan in beginning their rest periods. A short while ago, Flight Director Milton Windier, went around the control center and reviewed the status of the spacecraft with all flight controllers. That status is very good at this point. At the present time Apollo 10 is nearing the 60,000-mile mark, on route to the Moon. Presently 59,963 nautical miles [111,051 km] from Earth, and traveling at a speed of 7,627 feet per second [2,325 metres per second]. At 12 hours, 18 minutes into the flight; this is Apollo Control.
012:49:57 Cernan: Houston, Apollo 10. Over.
012:50:03 Engle: Roger. Go ahead, 10.
012:50:07 Cernan: I'm wondering if you can tell me anything about the way this PTC-REFS PTC G&N system is operating. We seem to be noticing quite a few thruster firings from here, and we are wondering what kind of on-time propellant consumption we're going to have out of this sort of thing.
012:50:32 Engle: Yes. Okay. Let me - Let me take a check and see if that's normal, to be firing that often.
012:50:41 Cernan: Hey, it seems to be kicking when we get on the edge of the deadband, just about almost all the time.
012:50:56 Engle: Roger. Okay.
012:54:28 Engle: Apollo 10, Houston.
012:54:31 Cernan: Go ahead, Joe.
012:54:33 Engle: Okay. For no longer than we've been monitoring it, it looks like the fuel consumption in this mode isn't too bad at all. In fact, it's just about what they figured you'd be using. We would suggest that you go back two and zero out your attitude. That'll give us some help there. And, unless the thruster firing is bothering, as far as the sleep concerns, we'd suggest that you stay in the 20-degree deadband. We could go to 30-degree deadband, but we'd rather stay in 20, unless it's bothering you.
012:55:44 Cernan: All right. I don't reckon I understood exactly what you're saying. You're saying that actually it's going to take less gas to go back and start over again, than it would to keep on going like this? Or not?
012:56:00 Engle: Well, I think the idea of zeroing out your attitude, Gene-o, is that it'll be - You won't get some firing for a while. Is - is the firing bothering - bothersome as far as the sleep goes? Or are you just concerned about fuel consumption alone?
012:56:16 Cernan: Well, every time the engine fires, it wakes you up.
012:56:20 Engle: Yes, I can understand.
012:56:26 Engle: I don't know that 30 degrees would be that much better. You're still going to get some firing. It'd probably be a little bit longer between firing.
012:56:38 Stafford: Yes, Joe. The thing that's kind of amazing is what was pointed out on 9. It seems like a real flexible structure when it fires in pulse. The whole thing shakes and it goes through about three cycles when it fires. I mean the - the structure vibrates for about three cycles.
012:56:53 Young: Also, the roll is up now to three-tenths of a degree per second, just about, and there is some yaw in there, and some pitch.
The initial PTC roll rate was 0.1 degree per second.
012:57:42 Engle: 10, this is Houston.
012:57:43 Stafford: Houston Apollo 10.
012:57:44 Engle: Roger. Go ahead, Tom.
012:57:45 Stafford: Go ahead.
012:57:47 Engle: Okay, Tom. Look - looking at it, Tom, we don't really see any way to get away from it. We could go to 30-degree deadband but you'd still get the thruster firings. That means they'd still be waking you up. As far as fuel consumption is concerned, it doesn't look, from the data that we've got monitoring it no longer than we have, it looks like it's just about what they figured. The fuel consumption isn't going to be too - too big a factor, but I can understand the thruster firings keeping waking you up, and I'm not real sure how to get away from it. I guess we're going to have to scratch our heads a while on that. The only advantage to zeroing out these attitudes is that it'll be a while before it fires again, but it eventually will start firing.
012:58:37 Stafford: Yes, I was wondering how much it was going to take us in fuel to go zero then out and get all set up again?
012:58:46 Engle: Roger. I - I think fuel wise you're just as well off to leave it like it is. We just thought that we might be able to get away with for - with having - giving you a little time before they started firing again to get back to sleep but -
012:59:03 Stafford: Yes. ...
012:59:13 Stafford: We're just going to leave it like it is for a while, okay?
012:59:16 Engle: Okay. Well, I don't think the fuel that you'd use getting back to the - zeroing out the attitudes Tom, would be anything to worry about. It will give you a little time to get back to sleep before it starts firing again. So I guess, that's kind of your option depending upon how bothersome it is. If you want to give that a try, why you could.
012:59:36 Stafford: Well, why don't we give it a try and see how she goes?
012:59:38 Engle: Okay.
This is Apollo Control at 13 hours into the flight of Apollo 10. A short while ago, we received a call from Gene Cernan aboard the spacecraft. He reported that the crew had noticed frequent firing of their attitude control thrusters, and they want an update from the ground on whether or not this was normal, and whether or not flight controllers here in Mission Control felt this would adversely affect their Reaction Control System propellant budget. The response from the ground to both questions was negative. They did not seem to feel that there would be any adverse effects on the propellant budget, and did not see anything abnormal in the thruster firing. We'll play back that conversation for you now.
As you heard in that conversation, Stafford and Cernan remarked that the thruster firing seem to be keeping them awake. Stafford remarked as to how the thrusters, when they fire, seem to cause the entire system oscillate about 3 cycles. The resolution to the problem was not too clear, and apparently there is not a great deal that can be done about it. CapCom Joe Engle, said that we would continue to scratch our heads about it here on the ground and see if something could be done to minimize the amount the thrusters fire to maintain the Passive Thermal Control attitude, but that at this point, it didn't seem that there would be a great deal that could be done about it. At 13 hours, 8 minutes into the flight; Apollo 10 is at an altitude of 63,527 nautical miles [117,651 km] from Earth; traveling at a speed of 7,367 feet per second [2,246 metres per second]. This is Mission Control, Houston.
013:10:29 Stafford: Okay. Houston, Apollo 10. We have reinitialized and we're going back to sleep now.
013:10:33 Engle: Okay, Tom. We'll keep trying to work out a way to keep those things from firing so often. That's - that kind of caught me by surprise, but I - I can see where that would wake you up, all right. Does that - does it give you pretty much of a jar, or is it noise that wakes you up?
013:10:48 Stafford: Well, there's a dull thud, Joe, and you - and the whole stack vibrates and it damps in about three cycles. It's kind of a boom - then you can hear it go rum-rum-rum, you know, for about three cycles.
013:10:58 Engle: Yes...
013:10:59 Stafford: ...real mild thud...
013:11:12 Engle: Okay. We copy, Tom, and we'll keep working that problem trying to figure something out here, a little more satisfactory.
013:11:20 Stafford: Yes, I think it's the vibration more than the noise. It's not but just a real light thud when the jet fires but the whole stack goes to a real bending vibration for about three cycles. Again, it's a real minor cycle but you can feel it, and that's what keeps you awake.
Young, from the 1969 Technical debrief: "The first night, the Passive Thermal Control mode we set up was 0.1 deg/sec, with 20-degree deadband, pitch, yaw, and roll, G&N, and four quad control, with a roll disable. The spacecraft plus X-axis was normal to the ecliptic when we started. This immediately produced considerable thruster firings when the vehicle got to the deadband after a short period of time. The thruster firings continued throughout the night. They were very disturbing and it kept Tom and me awake."
Stafford, from the 1969 Technical debrief: "It was not so much the dull thud of the thrusters that kept me awake as it was the associated dynamics of the vehicle. The vehicle would go through about 3 or 4 oscillations."
013:11:41 Engle: Yes, Okay. I understand I guess the only - only alternative we've got right now is that we could go to that wider deadband, but you'd still get the firings; they'd just be little bigger intervals is all.
013:11:50 Stafford: Yes. We'll stay here and see how this works out. I got all the lights turned back down and I'm going back to sleep.
013:11:55 Engle: Okay. Sorry about that, See you later.
013:12:00 Stafford: All right.
This is Apollo Control at 13 hours, 28 minutes. Our spacecraft now at an altitude of 64,938 - 64,938 nautical miles [120,265 km], traveling at a speed of 7,271 feet per second [2,217 metres per second]. We've had one additional brief conversation with the crew concerning thruster firing. We'll play that back for you now.
Here in Mission Control, at the present time, we are going through a change of shift. Pete Frank and his team of - his orange team of flight controllers coming on to replace Flight Director Milton Windler, and the Maroon Team. The capsule communicator on the upcoming shift will be Astronaut Jack Lousma. At 13 hours, 30 minutes into the flight of Apollo 10, this is Mission Control.
This is Apollo Control; 13 hours, 55 minutes Ground Elapsed Time. Apollo 10 presently is outbound for the Moon at a distance of 66,823 nautical miles [123,756 km] from Earth. And traveling at a velocity of 7,145 feet per second [2,178 metres per second]. The orange team of flight controllers headed up by Flight Director Pete Frank, has taken over here in Mission Control, and it is estimated that the Maroon Team Flight Director, Milton Windler will be at a press conference in the main auditorium, building 1 at MSC for a change of shift press briefing, within the next 5 or 10 minutes. He's now putting on his jacket and is leaving the Mission Operations Control Room. Crew apparently is asleep now. We've had no recent communications in the last half hour or more or at least since the orange team came on. And at 13 hours, 56 minutes Ground Elapsed Time; this is Apollo Control.
Flight Plan page 3-14.
This is Apollo Control at 15 hours, 1 minute Ground Elapsed Time. Apollo 10 still coasting outward toward the Moon and it is continuing to decelerate. The velocity has dropped now to 6,867 feet per second [2,093 metres per second], and the spacecraft now is some 71,240 nautical miles [131,936 km] away from Earth. The Orange Team Flight Surgeon Ken Beers reported recently that the crewmen apparently are sleeping well at the present time. And all is going quiet here in Mission Control. The Flight Director is getting briefed from the various console positions on the present status of all the systems; the guidance system, and so on. And at 15 hours, 2 minutes Ground Elapsed Time; this is Apollo Control.
This is Apollo Control; 16 hours, 1 minute Ground Elapsed Time. Apollo 10, according to the space digitals display here in the control center, is now some 75,104 nautical miles [139,092 km] away from Earth. And traveling at a velocity, ever decreasing, of 6,640 feet per second [2,024 metres per second]. Apollo 10 - Apollo 10 presently is being tracked through the antenna at the Honeysuckle Creek, Australia tracking station. With handover to Madrid antenna at half past the hour - some 28 minutes from now. Crew is still asleep, at some 4 hours remaining in the sleep period. The only additions to the preflight Flight Plan has been a new set of stars for the program 23. This is lunar navigation, which is star and earth horizon sightings. At 25 hours, a new group of stars is being generated and will be read up to the crew after they wake up. And water dump at 23 hours, 30 minutes. Other than that, the previously published Flight Plan is still in effect. And at 16 hours, 2 minutes Ground Elapsed Time; this is Apollo Control.
This is Apollo Control. 17 hours, 1 minute Ground Elapsed Time. Apollo 10, at the present time, is 78,855 nautical miles [146,039 km] away from the Earth continuing to decelerate in velocity. Now showing a velocity of 6,435 feet per second [1,962 metres per second]. The latest estimate on the track or trajectory of the S-IVB third stage following the LOX blown down, or the sling shot maneuver after the LM had been extracted from the S-IVB, shows that the stage will pass by the Moon's trailing edge or eastern limb at approximately 79 hours Ground Elapsed Time. We'll miss the Moon by some 1,700 nautical miles. The crew of Apollo 10 still asleep at this time. All systems are functioning almost perfectly. And a little over 4 hours remain in the sleep period. This sleep period was extended from the previous planned 9 hours to approximately 11 hours, when they went to sleep earlier than scheduled. Wake up time is still with the pre-mission Flight Plan. And at 17 hours, 2 minutes Ground Elapsed Time; this is Apollo Control.
This is Apollo Control; 18 hours, 3 minutes Ground Elapsed Time. Apollo 10, presently now some one-third the distance out to the Moon, is now showing on the display here a distance from Earth of 82,659 nautical miles [153,084 km]; traveling at a velocity of 6,240 feet per second [1,902 metres per second]. During the sleep watch here in Mission Control, the Orange Team, about an hour ago, had played back for it the onboard television from earlier in the day. When most of the flight controllers that are on duty now were home sleeping, the events of the day earlier - the lift-off and all the TV passes took place and most of them consequently missed it. Things are rather quiet here in the Control Center. The crew still asleep. All systems in the spacecraft are functioning extremely well. And at 18 hours, 4 minutes Ground Elapsed Time; this is Apollo Control.
This is Apollo Control at 19 hours, 1 minute Ground Elapsed Time. Space digitals showing positions in velocity for Apollo 10, now show velocity at 6,077 feet per second [1,853 metres per second]. Altitude above Earth at 85,999 nautical miles [159,269 km]. And we have here a weather forecast from a spaceflight meteorology group, of the weather bureau, ESSA, which said this morning that weather conditions in the planned landing areas are expected to be satisfactory for the next three days. Ocean areas of concern should have partly cloudy skies winds, 14 knots, seas 4 to 8 feet, temperatures 70 to 76 degrees. The Atlantic area should have widely scattered showers each day. The outlook for the end-of-mission area, that is at 15 degrees, 7 minutes south latitude by 165 west longitude, is satisfactory. Crew is still asleep at this time, scheduled to be awakened at 21:30 Ground Elapsed Time, which ia about two and a half hours from now. And the control center's still rather quiet, everyone boning up on the Flight Plan activities and preparing for a handover in some 2 hours to the Black Team of flight controllers as they come aboard. At 19 hours, 2 minutes Ground Elapsed Time, this is Apollo Control.
This is Apollo Control; 20 hours, 1 minute Ground Elapsed Time. Apollo 10 presently is some 89,499 nautical miles [165,751 km] away from Earth, continuing to slow down in its 2½-day trip to the Moon. Velocity is now 5,914 feet per second [1,803 metres per second] and here in Mission Control we are still monitoring the rather easy rest period of the crew, the first sleep period for the mission. We've got about another hour and a half in the rest period after which the crew will have their status report, get a consumables update from the Control Center here, also Flight Plan update for the coming day's activities, purge the fuel cell oxygen, and they will be given a new set of stars for the Program 23 exercise, that is the star- and Earth-horizon lunar navigation at 25 hours. It seems the original set of stars has some interference because of the field of view restricted by the Lunar Module out the window while in a docked configuration. Incidentally, the combined weight of the 2 spacecrafts, the LM and the Command Service Module, now stands at 94,027 pounds [42,747 kg]. We are now tracking through the Madrid antenna and will continue to track for another 5 hours, handing over to Goldstone at that time. All going well in the mission of Apollo 10. And at 20 hours, 3 minutes Ground Elapsed Time; this is Apollo Control.
This is Apollo Control; 21 hours, 1 minute Ground Elapsed Time; as Apollo 10 nears the 100,000-mile [185,200 km] mark in its trip from Earth out to the Moon. The distance now stands at 92,836 nautical miles [171,931 km], continuing to decelerate. Now showing velocity in feet per second of 5,765 [1,757 metres per second]. The crew has still not called back to the Control Center here, although the Flight Surgeon reports that Stafford and Cernan apparently are awake and John Young is still in a rather deep sleep. Members of the Black Team of Flight Controllers are beginning to drift into the Control Room here to take over from the Orange Team. The handover time will be half past the hour. We'll monitor the air-ground continuously and pick it up when the conversation does resume and the crew does wake up and begin their day's work, get their breakfast, and so forth. And at 21 hours, 2 minutes Ground Elapsed Time; this is Apollo Control.
This is Apollo Control; let's join the conversation in progress with Apollo 10.
021:31:39 Young: Houston, Apollo 10. Over.
021:31:44 Duke: Good morning, Apollo 10. You fellows slept in a little this morning.
021:31:51 Young: Yes, it's really great up here.
021:31:54 Duke: Yes, we can tell you like it.
021:31:56 Stafford: Yes we all ...
021:31:59 Duke: How did you sleep last night?
021:32:04 Young: Oh, we slept fine. Hey, we've got our morning weather report for you; you may be interested in it.
021:32:09 Duke: Roger. Go ahead.
021:33:10 Young: Roger. It's a European/African weather report. Portugal - Portugal is clear. Spain - Western Spain is clear, eastern Spain along the Med is under clouds. Italy - Italy is clear south of about Rome. Sicily - Sardinia and Corsica are under partly cloudy to cloudy skies. Greece is clear. Crete's clear. Turkey is under very scattered clouds. Bulgaria is clear with partially scattered clouds, but the rest of Europe is mostly under the clouds. There's a large part of the Soviet Union north of the Black Sea that's in the clear, but the rest of it appears to be under clouds, too. Arabia appears to be clear. Israel, clear. Jordan, clear. Libya and Egypt are clear except for a cloud strip along the center of the country in Saudi Arabia that runs from Saudi Arabia across the Sinai Peninsula and through Egypt. Africa is clear in the desert to the north and cloudy farther south. It's clear pretty much to the south except for the Cape where South Africa appears to be under the clouds. That's your morning weather report from about 100,000 miles.
021:33:34 Duke: Roger. Thank you, Apollo 10; the only thing missing was the music.
021:33:40 Duke: It looks like you're starting out the day real good there; we've go - go ahead.
021:33:47 Young: That's a special effect we're not carrying today.
021:33:54 Duke: Looks like old Charlie Brown is motoring right along in good shape, there; your consumables are ahead on everything, and Snoopy is hanging in there real well, too. Your midcourse correction will be on time and will be only 49 feet per second [14.93 metres per second], and we have a Flight Plan update when you are ready to copy.
021:34:17 Stafford: Okay; stand by. We want to get, a couple of pictures of Europe; we're in good position right now.
This is Apollo Control now, waiting for conversation to resume; that global weather report was by John Young. Apparently at 100,000 miles [185,200 km] out, he has a pretty good view of what the cloud cover and the weather situation is all over the visible face of the earth. We'll stand by monitoring this circuit for resumption of conversation.
This is Apollo Control; while we are waiting for the crew to get things sorted out so they can continue the Flight Plan updates and beginning the day's activity, Flight Director Glynn Lunney is briefing his team as they come aboard, and on all the things that have to be done today. Here comes the crew.
021:37:29 Stafford: Houston, Apollo 10.
021:37:22 Duke: Go ahead, Tom. Good morning.
021:37:36 Duke: How do you read me, Tom?
021:37:39 Stafford: Roger. Loud and clear. Like I told Jack earlier, we had a real great night's sleep, all three of us feel tremendous this morning, and it looks like we're running ahead on all consumables.
021:37:50 Duke: Roger. Good show. The only thing we really have for you when you can get squared away is a Flight Plan update - and we need some RCS totals I think on the consumables - about the only thing.
021:38:03 Stafford: Okay. You ready to copy?
021:38:05 Duke: Roger. Go.
021:38:06 Stafford: I'll give you - okay. On Ring A, 91 percent; Ring B, 94 percent. Ring C, 96 percent; Ring D, 92 percent.
021:38:28 Duke: Roger. We copy all that.
This is Apollo Control; Tom Stafford reported the percentage of propellants remaining in the various quads instead of rings, he said rings, although he probably meant quads on the Service Module. A, B, C, D; 91, 94, 96 and 92 percent, respectively on those 4 quads. We'll continue to monitor for further conversation - the various slips of paper being passed around here with all the Flight Plan updates - and Capcom is getting ready to jump in; let's listen.
021:39:56 Cernan: Morning, Charlie. We're ready to go ahead and copy your update.
021:40:00 Duke: Roger. On the Flight Plan, Gene?
021:40:03 Cernan: Yes, that's affirmative.
021:40:06 Duke: Okay. At crew convenience, we'd like you to get your personal dosimeters and put them on your person. It's no big deal on this, so if you don't feel like unstowing the suits, it looks like they are still on the suits, so it's your convenience on that. And at no later than 23 plus 30, we need a waste-water dump. And for John's P23 - Go ahead.
021:40:46 Stafford: Okay. I was going to say John wants to get a P52 in here before the midcourse, before that dump.
021:40:52 Duke: Roger. That's why we scheduled it no later than 23:30, Tom. We thought that would be a convenient time to get it in, and then schedule the P52 about an hour later.
021:41:07 Cernan: Okay, Charlie. Go ahead.
021:41:10 Duke: Okay, and at 25 plus 10, the P23 sightings - again, we forgot that Snoop was out there, so we have an update for your attitude and for the set - set stars - the stars for set 3 and 4. The attitude - We'd like a roll of 078 [degrees], pitch of 010 [degrees], and a yaw of 000 [degrees]. Okay, for sets 3 and 4...
021:41:44 Cernan: Okay. What about the stars?
021:41:49 Duke: Okay. I'm giving you those now. Sets 3 and 4 for substitute Nunki, N - U - N - K - I, 37 and far side.
021:42:03 Cernan: Charlie, you cut off. Start the stars again, would you? All I got was roll, pitch, and yaw.
021:42:07 Duke: Okay. For sets 3 and 4, Nunki instead of Antares, and we want the far side on Nunki.
021:42:31 Cernan: Okay. Is 1, 2, and 5 the same?
021:42:34 Duke: That's affirmative.
021:42:38 Cernan: Okay. I got 20 - let's see - for P23, roll 078 [degrees], pitch 010 [degrees], and yaw all zeros [degrees], and sets 3 and 4 changed to Nunki, far star.
021:42:50 Duke: That's affirmative. And at 27 hours after the midcourse, we'll have an update for you on your P37 PADs for 35 and 44 and 53 hours.
021:43:05 Cernan: All right.
021:43:07 Duke: And that's all we got this morning on the Flight Plan.
021:43:18 Cernan: Okey doke. I think I got it all, Charlie. We'll get that waste-water dump in prior to 23:30 and we'll make a valiant effort on the dosimeters.
021:43:28 Duke: Roger. We copy. And as soon as you settle down to breakfast, we'll, if you like, we got a news summary here we'll be glad to read up to you.
021:43:43 Cernan: Okay. Guess you can go ahead and read it right now, if you'd like.
021:43:46 Duke: Roger. Stand by. Let me get this squared away here with Flight, and we'll be with you in a minute.
021:43:54 Cernan: Okay. We'll just wait for you to continue on here. Go ahead with the planned O2 purge at 22 hours, is that correct?
021:44:03 Duke: Stand by. That's correct, Gene.
021:44:07 Cernan: Okay.
021:44:33 Duke: Hello, Apollo 10, Houston. We'd like you to give us a little idea of how the thruster activity disturbed you during the night and whether we could go ahead and continue on tonight with the same plan.
021:44:48 Stafford: Yes, Charlie. Roger. What happens is, if you've ever flown a B-47 or even a C-133, it seems like a loose dynamic structure after the thruster fires. The noise doesn't bother you at all; it's just the dull thud, but then you have an oscillation to three or four cycles after, with just a little minor oscillation that damps out.
021:45:09 Duke: Right.
021:45:10 Stafford: There's no problem; just keep on going; we slept good.
021:45:11 Duke: Okay. Fine, Tom.
021:45:12 Cernan: Charlie, it gives me the feeling like just a little minor pulse - waves that big engine bell back there around just enough to vibrate until it damps out.
021:45:24 Duke: Okay. Fine. Well, we will continue on, then. The surgeon, as I came on this morning, said that it looks like you all were sleeping like a log. How was your position on the couch there, Gene? Real comfortable?
021:45:40 Cernan: Yes. Pretty good.
021:45:41 Duke: Okay. Fine. Well, we will continue on, then.
021:45:44 Cernan: Works more.
021:45:45 Duke: Say again.
021:45:46 Stafford: Yes. Okay. For your friendly man on the left dosimeter reads 26021.
021:45:53 Duke: Roger.
021:45:57 Cernan: Okay, Charlie. Mine is 15030.
021:46:05 Duke: Copy.
021:46:09 Young: And mine is 05027.
021:46:15 Duke: Roger, John. 05027.
021:46:21 Young: I believe that's right, Charlie.
021:46:23 Duke: Right.
021:46:24 Young: These are very small numbers.
021:46:27 Duke: Roger. It's pretty early.
This is Apollo Control at 21 hours, 51 minutes into the mission. We will continue to stand by live. CapCom Charlie Duke does plan to read up a news summary to the crew. Apollo 10 is now 95,629 miles [177,104 km] from the Earth, velocity 5,648 feet per second [1,722 metres per second], and we're showing a weight of 94,027 pounds [42,747 kg].
021:51:47 Duke: Hello, Apollo 10. Houston. We're ready with a summary of news and sports as compiled by your friendly third floor astonisher, Jack Riley, and his office. Are you ready?
021:52:02 Cernan: Man, we are just about ready for anything.
021:52:04 Duke: Roger. This is a news team of McCandless and Duke, then. Newspapers, television, and radio are concentrating on the flight of Apollo 10. The Houston Post banner read 'Apollo 10 Out of This World,' and for the first time in memory, the entire front page of the Post is all space news. The newswires are commenting on the quality and quantity of the TV transmissions yesterday.
021:52:30 McCandless: Senator Barry Goldwater paid surprise visits to the Stafford and Young homes yesterday. He said he came to Houston because he had been to the Cape before and each time the launch had been postponed. Other than the Apollo 10 mission, the world has been relatively quiet.
021:52:45 Duke: In other news highlights, Leonard Bernstein left his position as conductor of the New York Philharmonic Orchestra.
021:52:52 McCandless: Governor Rockefeller is in Latin America this week on a presidential assignment.
021:52:56 Duke: And a Siamese cat in Vancouver, Washington, is mothering three baby skunks who are orphans.
021:53:04 McCandless: A Chicago art collector paid $12,000 for a 120-year-old paperweight.
021:53:11 Duke: And US Air Force planes are seeding clouds in the Philippine Islands to combat drought conditions.
021:53:17 McCandless: In the sports news, the Astros beat the Cubs for the second time in 2 days. The Sunday afternoon battle at the Astrodome ended with the Astros on top 6 to 5 before a crowd of over 13,000. In other games, it was Los Angeles Dodgers 6, Pittsburgh 5; St. Louis 6, San Diego 5; Atlanta 8, Montreal 3; Philadelphia 9, San Francisco 8.
021:53:46 Duke: And in the American League, it was Baltimore 5, KC zero; Detroit 8, Minnesota 2; Washington won two games with Chicago, both by 3 to 2; New York beat California twice, 3 to 1 and 1 to 0; and Seattle beat Boston 9 to 6.
021:54:07 McCandless: The trials at the Indianapolis speedway were washed out yesterday.
021:54:12 Duke: And Majestic Prince, who won the Preakness on Saturday, may not run in the Belmont Stakes, June 7. The horse's owner reports the horse is tired and has lost weight. Too bad. Majestic Prince is the first horse since 1948 that has a chance to win the Triple Crown.
021:54:32 McCandless: And here is your horoscope readings for today, Apollo 10. Tom Stafford: You should concentrate on finishing things that you have already started. Today's pace will be moderate. Use this time to take inventory.
021:54:46 Duke: And, Gene-o, your horoscope reads: Give careful thought to your working and driving habits. Do something nice for your friends.
021:54:54 McCandless: John Young: You will have a slow day today. This will give you time to concentrate on the work ahead. You will enjoy your surroundings and companions.
021:55:04 Duke: And the weather in Houston is beautiful this morning. The sky is clear and temperatures will rise to the low to mid-80's. Last night a clear, thin crescent of the Moon was visible. And this finishes the first annual McCandless-Duke radio-cast. Over.
021:55:22 McCandless: Roger. Good morning, Charlie.
021:55:23 Duke: Good morning, Bruce.
021:55:26 Stafford: You guys are too much down there. That's fantastic.
021:55:29 Young: Boy, you outdo me. I quit. You can give the weather next time, too.
021:55:34 Duke: Roger.
021:55:36 Stafford: That was tremendous.
021:55:37 Cernan: You're going to put someone out of business down there if you don't watch out.
021:55:42 Duke: Maybe you guys.
021:55:45 Cernan: Hey, we'll keep fanning the 'peacock' up here and you guys keep talking.
021:55:48 Duke: Okay. Fine.
021:56:18 Stafford: Hello, Houston. Apollo 10.
021:56:20 Duke: Go, 10.
021:56:23 Stafford: Okay. We just want to get this on the record. When we woke up this morning and took a drink out of the water gun, everything was just great and everybody had a good drink; and then I took a drink, and it is absolutely horrible.
021:56:35 Duke: Roger. That's kind of what we figured.
021:56:36 Stafford: Yes. It started out earlier this morning. It was good, and then I got a horrible slug of chlorine, and my mouth is still burning. No problem, And so did John.
021:56:47 Duke: Okay. I guess were getting a good...
021:56:49 Stafford: I just wanted to get it on the record.
021:56:50 Duke: Roger, Tom. I guess you were getting it out - the good stuff was in the lines there out of the tank, perhaps, or something. And once you got the tank water it was bad. We kind of figured.
021:57:01 Stafford: Yes.
021:59:17 Duke: Hello, 10. Houston.
021:59:23 Cernan: Go ahead, Charlie.
021:59:24 Duke: Hey. Roger, Gene. Last night when you chlorinated the water did you - We'd like to know if you left the potable tank inlet valve open for 10, minutes after you chlorinated.
021:59:38 Cernan: We discussed that with the ground and they said no.
021:59:45 Duke: Okay. I don't quite understand the problem from this end. We'll square it away and then get back with you. On this waste-water dump, we'd like you to give us the word exactly when you plan to do it. We have telescopes just about all over the world going to photograph this thing, and we'd like to give them as much notice as possible. Over.
Flight Plan page 3-17.
022:00:17 Cernan: Okay.
022:00:19 Duke: Roger.
This is Apollo Control at 22 hours, 4 minutes. There is a discussion going on in the Control Center here now concerning procedures that may be able to eliminate this strong chlorine taste that Tom Stafford was talking about. The EECOM officer is working the problem. Charlie Duke will probably be passing up some suggestions on clearing that problem up. We are showing now Apollo 10 96,235 miles [178,226 km] from Earth at a velocity of 5,624 feet per second [1,714 metres per second]. We will continue to stand by live for any transmissions.
This is Apollo Control at 22 hours, 8 minutes. Charlie Duke is going to put a call to the crew here very shortly.
022:08:40 Duke: Apollo 10, Houston. Before you use any of your water to mix any of your food, would you hold off? We're trying to get this resolved. Over.
022:08:52 Stafford: Okay, Charlie. We thought the chlorine would taste better in fruit juice than it would by itself. We've already pressed on.
022:08:59 Duke: Okay. It's probably going to be pretty horrible. Stand by one. We will have some word for you.
022:09:38 Duke: Apollo 10, Houston.
022:09:43 Stafford: Go ahead.
022:09:44 Duke: Roger. Tom, last night when you chlorinated and we told you not to open the potable tank inlet, it turned out we didn't get any of that chlorine mixed and now that stuff is in the lines, and when you draw off from the gun it's not mixed at all with any of the water. So we recommend that you open the potable tank inlet now, and take a bag and draw off about a bag full of water then get rid of it. Over.
022:10:19 Stafford: Roger.
022:10:31 Young: Charlie, I'm going to go ahead and give you an O2 purge now.
022:10:35 Duke: Roger.
022:10:41 Cernan: Okay, Charlie. That's why I asked the question last night.
022:10:44 Young: Purging fuel cell 3.
022:10:46 Duke: Right. Well, I didn't get a briefing on it, John, but it looks like we just gave you the wrong word, Over.
022:10:55 Stafford: Yes. That's why both of us were asking quite a few questions. If we had a complete isolated service water tank, why would we want to slug a slug of chlorine into it when no new water had come in?
022:11:04 Duke: That's a good question.
022:12:24 Duke: 10, Houston. On your orange juice this morning, we recommend that you probably not drink - you not drink that and you consider getting rid of it. It's possibly almost pure chlorine in the juice.
022:12:46 Stafford: Okay.
This is Apollo Control at 22 hours, 16 minutes. We'll take this release line down now and come back up when there is further conversation. They're calling now.
022:16:36 Young: Houston, Apollo 10. Over.
022:16:39 Duke: Go ahead, 10.
022:16:42 Young: Okay. The LM's Delta-P is up to nine-tenths today.
022:16:46 Duke: Roger. Copy, John.
022:16:48 Young: It's 0.09.
022:16:49 Duke: Roger.
022:16:50 Young: 0.9.
022:16:51 Duke: 0.9. Got you.
022:25:55 Cernan: Charlie, I'm going to start battery B charge here in the next 30 seconds.
CM Pyro battery B
022:26:00 Duke: Roger. We copy, Gene.
This is Apollo Control at 22 hours, 37 minutes. Apollo 10; 98,084 miles [181,651 km] from Earth; velocity, 5,547 feet per second [1,691 metres per second]. We have a conversation in progress. We will tune in.
022:36:30 Young: Houston, Apollo 10. How much notice for that water dump? Over.
022:36:35 Duke: Roger. Just as much as possible, 10, and that's all I can tell you, We would like an hour or so, I guess.
022:36:46 Young: It will be an hour from now then.
022:36:48 Duke: Okay. Looks like we got - Why don't we go ahead and plan it for 22:30? That will be fine. 23:30 as planned, John? We will put the word out.
022:37:00 Duke: Okay. Fine.
022:37:02 Duke: Roger.
022:37:03 Duke: We will put the word out.
022:37:04 Young: For 23:30.
022:37:05 Duke: Roger.
This is Apollo Control. Astronomers at a number of observatories throughout the world will attempt to watch this waste water dump scheduled for 23 hours, 30 minutes into the mission. The midcourse correction is scheduled for an elapsed time of 26 hours, 32 minutes, 56 seconds. It will be done with the Service Propulsion System, 49 feet per second [14.93 metres per second] delta-V. Duration of the engine firing, 6.7 seconds. With this maneuver, we will be doing part of the correction to place Apollo 10 over the proper ground track at the Moon. We want the same ground track that the Apollo 11 spacecraft will follow. We will attain part of it with this maneuver, and then the remaining part with the Lunar Orbit Insertion number 1 burn. This is Mission Control Houston.
022:47:54 Duke: Hello, Apollo 10. Houston. We'd like you to close the potable tank inlet valve now.
022:48:02 Stafford: Okay. I'll get it.
022:57:25 Cernan: Houston, this is 10.
022:57:30 Duke: Apollo 10, this is Houston. Go ahead.
022:57:35 Cernan: On this cycle, the Cryo fans - how long do you want us to leave them on?
022:57:41 Duke: stand by.
022:58:24 Duke: Apollo 10, this is Houston. On the Cryo fans, 2 minutes for each tank. Same for H2 and O2. Over.
The cryo fans in the H2 and O2 tanks each have two parallel 3-phase a-c circulating fans, to circulate the fluid over the heating elements to maintain a uniform density and decrease the probability of stratification. See illustration below.
Cryo tank heater and fan
022:58:32 Cernan: Okay.
022:58:34 Duke: Roger. Out.
This is Apollo Control at 22 hours, 59 minutes. Apollo 10 is 99,263 miles [183,834 km] from Earth. Velocity is 5,500 feet per second [1,677 metres per second]. We had some brief air-ground conversation just a few moments ago. We'll play that for you.
This is Apollo Control at 23 hours, 4 minutes. The Flight Surgeon, Dr. Willard Hawkins, advises that the radiation exposure to the crew to date is the equivalent of about three chest X-rays. This includes that received during passage through the Van Allen radiation belt, the area of highest radiation. We're having conversation now.
023:04:16 Cernan: Houston, this is 10.
023:04:20 Duke: Go ahead, 10.
023:04:24 Cernan: Listen. You guys were so good to us with the news this morning that we thought we'd bring you a little disc jockey work from up here, if you're prepared.
023:04:32 Duke: Roger.
023:04:39 Cernan: This is Tom and John on the guitar and three of us singing.
023:04:43 Duke: Okay.
023:05:00 Cernan: Here it comes.
023:05:01 Duke: We're ready.
Spacecraft: Music: "Up, Up, and Away".
023:07:27 Young: Sure hope you enjoyed the last one.
023:07:28 Duke: Hey, that was really beautiful. Somebody's voice is changing, though, or you stowed somebody away up there.
023:07:37 Cernan: I thought that song was sort of apropos.
023:07:40 Duke: It really was beautiful; it was really great, you guys. Y'all been practicing a lot.
023:07:46 Cernan: We had trouble stowing the drum aboard, but other than that, it came out pretty well.
023:07:52 Duke: Roger. We got you.
023:07:54 Stafford: Delta 5 psi makes your voice a little higher, Charlie [laughter].
023:07:56 Duke: Oh, oh, that's right. I forgot.
023:08:13 Duke: Are we having an encore, or are you saving your next rendition for later on?
023:08:19 Stafford: No, that's enough for one day.
023:08:22 Duke: I believe it [laughter].
023:09:03 Young: Got a few more, Charlie, but we will save them for a while.
023:09:06 Duke: Roger.
That's another space first for Tom Stafford, although it probably won't rank as high in the technical annuals as the first space rendezvous he and Wally Schirra performed.
This is Apollo Control at 23 hours, 20 minutes. Apollo 10 is 100,378 miles [185,899 km] from the Earth traveling at a velocity of 5,456 feet per second [1,663 metres per second]. We are in conversation with the crew concerning the water.
023:18:21 Duke: Hello, 10. Houston.
023:18:28 Stafford: Go ahead.
023:18:29 Duke: Roger. We were wondering, when you drew off your water to purge the lines, at what point you took it off. We think you ought to do both the drinking water supply and the food preparation unit. Over.
023:18:47 Stafford: It's too late now, Charlie. We've already gone through it.
023:18:50 Duke: Roger. Could you tell us where you drained it off, Tom?
023:18:56 Stafford: Yes. In my grape juice.
023:18:59 Duke: Okay.
023:19:04 Stafford: Yes. It came off the food servicing thing.
023:19:07 Duke: It came off ... okay, the...
023:19:13 Stafford: By the time you had already got the word to us - Don't sweat it, Charlie. Okay?
023:19:22 Duke: Roger.
This is Apollo Control at 23 hours, 28 minutes into the mission. Apollo 10 is 100,808 nautical miles [186,695 km] from Earth; velocity, 5,439 feet per second [1,658 metres per second]. We have given Apollo 10 a Go for the waste water dump at 22 hours, 30 minutes, and here is that conversation.
023:26:43 Young: Houston, Apollo 10. Over.
023:26:47 Duke: Go ahead, John.
023:26:51 Young: Got a Go for the dump at 23:30?
023:26:53 Duke: Stand by.
023:27:09 Duke: 10, Houston. You are Go for the dump at 23:30.
023:27:18 Young: Roger. Thanks.
023:30:04 Stafford: Okay, Houston, Apollo 10. We've started the water dump.
023:30:07 Duke: Roger. Copy, Tom.
023:30:11 Stafford: And it's really filling the sky out here, Charlie.
023:30:13 Duke: Roger.
023:30:17 Young: Boy, it really is.
023:31:08 Young: Boy, Charlie? Is this to fix the problem so it doesn't mess up the tracking? Is that what you're trying to do?
023:31:12 Duke: That's affirmative, John. We would have to dump before - we wanted to dump as close as possible to a midcourse - before midcourse, and if this one goes as planned, we wouldn't do another one until LOI. and we'd be over the - over the limit.
023:31:33 Young: Understand.
023:31:49 Duke: 10, Houston...
023:31:50 Stafford: Houston, Apollo 10. For comparisons - Go ahead, Charlie.
023:31:54 Duke: I'm sorry; I cut you out, Tom. Go ahead.
023:31:58 Stafford: I was just going to say, for comparative sizes, if we try to look at this stuff with the telescope there is a factor of 10 or 20 times the number of particles we have from our other dumps, but the particles are all about - maybe one-tenth the size.
023:32:12 Duke: Roger. We copy.
023:32:21 Duke: 10, EECOM's just corrected me. It looks like we'll have to do the dump once a day. We scheduled it a this time as close to midcourse as possible and yet still allow you, we hope, to clear it away so you can do the P52.
023:32:40 Young: Yes. There's a lot of stars out there right now.
023:32:42 Duke: Yes. I'll bet.
023:32:47 Duke: 10, I overlooked the consumables update we owed you at 23 hours. If you'd like to copy that, we have it for you any time.
023:33:02 Stafford: Okay. Go ahead
023:33:03 Duke: Okay. Your H - At 22:30 GET, your RCS totals were 92 percent across board. We had an H2 of - total of 48.2 pounds and an O2 total of 565 pounds.
023:33:29 Young: Okay, Charlie. That's at 22:30?
023:33:31 Duke: Roger.
023:34:50 Young: Houston, Apollo 10. Over.
023:34:52 Duke: Go ahead.
023:34:56 Young: Okay. I've got something out here now tracking that. I wonder if that could be the S-IVB. It keeps - seems to rotate and glimmer. It's not a - it's not a particle, Over.
023:35:08 Duke: Roger. Stand by, Tom. I'll see if we can get you - Correction, John, I'll see if I can get you some word on that.
023:35:23 Young: It's a long ways off.
023:35:26 Duke: Okay.
023:35:29 Young: It doesn't even fill the center of the reticle. It goes about half - half the width of the reticle.
023:35:38 Duke: Roger.
023:35:39 Young: Half the width of the lines in the center of the reticle.
023:35:43 Duke: Roger. Copy.
023:36:12 Young: Shaft is 947 and trunnion is 387 right now.
023:36:18 Duke: Roger. We copy, 10. We're copying down your attitude and your shaft and trunnion, and it will take us a while to run it out. The FIDO's are busy with the midcourse right now.
023:36:33 Young: Okay. Sure. That's something you can do post-flight if you want to.
023:36:39 Duke: Roger. And your water dump's okay. You can turn it off.
023:36:44 Young: Roger.
023:36:55 Young: We're in Pressure Relief 2, now.
Directs flow of excess potable and waste water to No.2 Pressure Relief valve. This valve provides automatic pressure relief.
In the event that both water tanks are full at the time the fuel cells are pumping, the excess potable water will be dumped overboard through the Pressure Relief valve on panel 352. However, automatic dumping through the relief valve is not desirable because the pumps in both the potable and waste water systems discharge water intermittently, rather than in a steady stream. Dumping water through the relief valve (No 2 pressure relief valve) in spurts results in some flash-freezing, which could result in a temporary blockage of the dump line. To preclude this the Pressure Relief valve was modified by removing the poppet of one of the two relief valves, so that it could be used as a dump valve, to dump water in a steady stream manually.
"H2O Pressure relief valve
023:36:58 Duke: Roger.
This is Apollo Control. Apollo 10 dumped about 18 pounds of water from 26 pounds down to 8 pounds of waste water.
This is Apollo Control at 23 hours, 41 minutes. We're showing Apollo l0's distance from the Earth now at 101,466 nautical miles [187,914 km]. Velocity; 5,414 feet per second [1,650 metres per second]. John Young reported he is tracking something in the optics that rotates and glimmers, and it's a long way off. He believes it may be the S-IVB, the third stage of their booster. Flight Controllers here will attempt to verify that a little bit later. They're busy now on the midcourse correction and following that work they will take a look at where the S-IVB is and attempt to verify for John whether that is indeed what he is seeing.
023:42:48 Young: Houston, this is 10. We're going to run through the main regulator checks. You want to watch it?
023:42:53 Duke: Roger. We're standing by.
This is a test of the redundant components of the environmental control system being performed now.
023:44:56 Duke: Hello, 10. Houston. We'd like you to repeat the second Reg check here. We noticed a funny on the manifold pressure.
The oxygen Main Regulator (panel 351) reduces the supply pressure from the SM O2 cryo tanks to 85-110 psig for use by the subsystem components. The regulator assembly is a dual unit regulator, A and B, which is normally operated in parallel. Two toggle valves at the inlet to the assembly provide a means of isolating either of the units in case of failure, or for shutting them both off. Integral relief valves limit the downstream pressure to 140 psig maximum. The output of the Main Regulator passes through a flowmeter, then is delivered to the Water & Glycol Tanks Pressure regulator, the cabin pressure regulator, Emergency Cabin Pressure regulator (all on panel 351), the O2 Demand Regulator (panel 380), the Direct O2 valve (panel 7), and the Water Accumulator valves (panel 382).
Main O2 Regulator - Panel 351
023:45:06 Young: Okay. Well, I let in - I pushed it in and then I let it out. Would that account for it?
023:45:10 Duke: Stand by. I think so.
023:45:12 Young: I didn't hold it in the full time.
023:45:18 Young: I pushed it in for about 2 seconds, and then I let up on it, and then I pushed in on it again.
023:45:23 Duke: Roger. The EECOMs would feel warmer if you'd just do it one more time for us, John.
023:46:24 Duke: 10, Houston. Check looks okay to us.
023:46:30 Stafford: Okay.
023:46:32 Young: I'm sure glad about that, Charlie.
023:46:35 Duke: Say again.
023:46:39 Young: I said, I'm sure glad that thing works.
023:46:42 Duke: Yes.
This is Apollo Control at 23 hours, 51 minutes. Apollo 10's distance is now 102,017 miles [188,934 km], velocity 5,392 feet per second [1,644 metres per second]. Spacecraft weight 93,872 pounds [42,677 kg], This is Mission Control Houston.
This is Apollo Control at 23 hours, 53 minutes and we are in conversation with the crew.
023:52:38 Cernan: Hello, Houston. This is Charlie Brown.
023:52:42 Duke: Go ahead, Charlie Brown.
023:52:45 Cernan: We finished the ECS redundant component checks, and everything looks good from here.
Main O2 regulators

MAIN REG B vlv - close
O2 press - 90-110 psig (from MSFN if avail)
MAIN REG B vlv - open
MAIN REG A vlv - close
O2 press - 90-110 psig (from MSFN if avail)
MAIN REG A vlv - open.
EMER CABIN PRESS vlv - BOTH (OFF if suited)

Secondary Glycol Loop

Open cool atten panel (If req'd)
GLY DISCH SEC PRESS - 39-51 psig
SEC EVAP STEAM PRESS .1-.15 boiling.
>.16 not boiling.
After 5 min
SEC EVAP TEMP OUT - 40-50.5 deg F
SEC COOL LOOP EVAP - RESET for 58 sec minimum..
then off (ctr)
023:52:51 Duke: Roger. We copied it all, Gene. Looks Go to us, too.
023:53:04 Cernan: Sure appreciate the little news bulletin. Plan another one tomorrow, will you?
023:53:08 Duke: Roger. We'll have our morning report when we first come on for you.
023:53:17 Stafford: Yes, Charlie. We just can't tell you how great that sounded this morning. That was just tremendous.
023:53:22 Duke: Well, I'm glad you enjoyed it.
023:53:24 Stafford (onboard): When you come...
023:53:25 Young: Especially that horoscope; we wouldn't want these guys to do anything wrong.
023:53:29 Duke: No, sir. You got to watch them, John. We appreciated your little rendition from 90,000 or so out, too.
023:53:40 Young: Got that through the sextant. Boy, you could see everything. We could see the - You could see the Nile Delta just like you were down there; you could see the whole island of Crete; you could see Italy. You could see the whole - You could see the whole - whole coast of Europe all the way around, except it's all under the clouds.
023:54:01 Duke: Roger. Must be a fantastic sight. How...
023:54:08 Cernan: It is, babe. A little later if we can show it to you. it - it's just beautiful.
023:54:12 Duke: Roger.
023:54:16 Duke: How does the sextant bring out the landmarks, John? Do you think you'd have any trouble tracking from way out there?
023:54:24 Young: I don't think you'd have a bit of trouble; I think it'd be a piece of cake. Those places that are open that we always planned to use for landmarks, like that coastal land down off of Arabia, down there is just as clear as a bell right now. And yesterday Baja California was wide open, too.
023:54:44 Duke: Roger. We could see that real clearly on the TV.
023:54:50 Young: Yes, and it would really be a piece of cake to track - to do any star landmark work.
023:54:57 Duke: Roger.
023:55:06 Duke: You have any trouble looking at the stars before the dump? Could you see all the stars you wanted to see, John?
023:55:21 Young: Can't see any - Can't see any stars with the LM on there, Charlie, except in Auto Optics.
Young, from the 1969 Technical debrief: "It is recommended that with the LM attached, these sightings be planned preflight, so that it won't take a lot of attitude fuel and so that the stars aren't too far for the planet to be observed, because you're really limited with the Lunar Module on as to how much viewing area you have through which to look with the optics. After discussing this a couple of days prior to flight, we changed those in real time to allow us to save more fuel. The first set of sightings was for calibrating the horizon to my eye (and the horizon I was sighting on, according to the data, was 32 to 34 kilometers). This was a very hazy layer above the horizon that appeared to be the highest line above the horizon where I could see a useful attitude. It was definitely well above the cloudline. The star/horizon sightings were no problem and had gone just as in training. A simulator is a very useful device for doing star/horizon measurements. I recommend that a slide which shows the same kind of horizon that we saw on an actual spacecraft be put in the simulator to improve the horizon display. During the second period of star navigation sighting after the sleep period, the horizon was much less definite. In face, it appeared to be almost nonexistent. Those sightings were no problem. The Auto Optics worked beautifully and in many cases a complete pass of star/horizon sightings could be done with just the Auto Optics alone, and in every case where it was possible this method was used. It is very difficult to fly this vehicle with the CMC with the MIN-impulse controller. You just cannot think 'roll, yaw, and pitch' when the axis is 35 degrees from your primary control axis. Optics calibration in both sets was very difficult. It was repeatable in every case where it was required, but with the LM attached it is very difficult to find a star near the body of interest to calibrate. It is certainly recommended that if this is seriously going to be done with the LM attached that some automatic mode be developed to find the star. The optics in the spacecraft handle easily during navigation sightings."
023:55:28 Duke: Well, that's what I meant.
023:55:33 Young: Sometimes you can see stars; there's about a 10- or 20-degree angle when you're directly opposite the Sun where you can see stars.
023:55:43 Duke: Roger.
023:55:44 Young: But, you can't see them - You can't tell what stars they are, so they wouldn't be any good for a P51. However, I did recognize what I believed to be Mars, off the Earth, and Jupiter, because of its four moons, so you could use those for a P51.
Young, from the 1969 Technical debrief: "P51s would have to be done with the planets: Jupiter, in the vicinity of the Moon; and Mars, in the vicinity of the Earth, could be seen. And of course they are about 180 out from each other. which would make them very poor. We didn't try to Sun options, but we had filters onboard to use the Sun. I think they would work okay."
023:56:01 Duke: Roger.
023:56:04 Duke: How do - How are the particles? You still got the particles around now, or are they all gone?
023:56:15 Stafford: I can see a few out the left side window, but within 5 to l0 minutes, most of them have dissipated.
023:56:23 Duke: Roger.
023:56:46 Young: The dump particles are so fine; they don't seem to be as big as the other ones that come from the waste system dump that we make, and they are not as persistent, apparently, too.
023:56:58 Duke: Roger. we copy.
023:59:18 Young: Well, I can tell you from here that Cuba's under - got some thunder bumpers over it today.
023:59:23 Duke: Roger.
023:59:31 Duke: John, can you really - through the sextant, can you really get an idea of the three-dimensional effect of the clouds.
023:59:40 Young: No. It just sort of looks like a picture.
023:59:43 Duke: Roger.
023:59:45 Young: To me, anyway.
Previous Index Next
Day 1, part 6: Housekeeping and TV transmission Journal Home Page Day 2 part 8: Mid course correction and TV transmission