Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.
173:19:30 Duke: Hello, Apollo 10. Houston. We're to lose the High Gain. We'll come back around again at 173:25, and at that time we will be Go for High - the TV. Over.
173:19:44 Stafford: OK. Sounds real good, Charlie. Thank you.
Long comm break.
173:19:55 That's approximately 5 minutes from now. We will be getting another television transmission from Apollo 10 in about 5 minutes.
173:24:58 Young: Houston, Apollo 10. Over.
173:24:59 Duke: Go ahead, 10.
173:25:01 Young: Roger. Do you have a picture?
173:25:05 Duke: We're on the Omnis there, 10, and we'll - We'll be about another minute.
173:25:12 Young: Roger.
173:25:15 Duke: Hey, and we got some information on Snoop at 173:30, 5 minutes from now. He's 208,966 nautical miles [387,005 km] above the Moon, and he's 405,188 nautical miles [750,408 km] above the Earth. And stand by on his hyperbolic.
173:25:42 Young: Boy, he's getting up there.
173:25:50 Duke: And he's going hyperbolic with respect to the Earth and the Moon, so he's moving out away from us. And his velocity with respect to the Earth is 7,530 feet per second [2,295 m/s], and he's going into solar orbit.
173:26:07 Stafford: Wonderful. Looks like Snoop's going to take a long trip. Over.
173:26:10 Duke: A real long one.
173:26:54 Young: Houston, do you have a picture? Over.
173:27:22 Young: Roger. Looks like this is the Moon, and we're about 110,000 miles [204,000 km] from it. It still has a sort of a brownish cast to it, and it's still rotating very slowly. You can see when you look out your window tonight, you'll see it's only a three-quarter Moon or so.
173:27:53 Duke: OK. We just got it up - We just got it up on the...
173:27:58 Young: Roger.
173:27:59 Duke: ...on the telemonitor now.
173:28:02 Young: This is...
173:28:03 Duke: Excuse me, John. Go ahead. Over.
173:28:05 Young: This is a full zoom on the lens, so it actually is a little smaller than it is on your screen. It's hardly enough to make any definition out of it at all.
173:28:20 Duke: 10, Houston. We can apparently make out the mare, the colors on our Vidicon are - has a greenish cast to it, but I think the color quality for the commercial is a little bit better than this, but we [garble] see the maria on it. Over.
173:28:39 Young: Roger. And at about 110,000 miles [204,000 km], I don't think you expect to see very much.
173:29:11 Young: It'll be a couple of minutes before - before the Earth comes around, so let us show you the interior.
173:29:18 Duke: Roger. We're standing by for your smiling face. I've heard of the big eye before, but the big hand is ridiculous.
173:30:09 Duke: OK, 10. I think we're looking at Tom's right - left shoulder there now, and the Sun coming in his window. Yes. There's his old grinning face, clean shaven.
173:30:35 Young: Roger. This is a remarkable innovation. After spending a lot of money on mechanical shavers which always manage to leave the whiskers flying around in the atmosphere, somebody finally came out with the idea of using a straight razor and brushless shaving cream. You rub it on, it keeps the whiskers when you shave it off, you put it in a towel and dispose of it, and you end up clean shaven. And after 8 days of wearing a beard, I guess you're looking at a couple of guys who aren't much hippies.
173:31:13 Duke: That's amazing, 10. Absolutely. That's what the space age does for you.
173:31:19 Cernan: I'll tell you, Charlie. That's one of the most refreshing things that's happened in the last couple of days. That was really great.
173:31:25 Duke: You guys really look good, Gene. Over.
173:31:28 Cernan: You know, actually - you know, it feels a lot different. We were getting where we could barely stand ourselves there for a while.
173:31:45 Stafford: We'll take you down to the Lower Equipment Bay and show you how different our navigator looks today compared to yesterday. On the panel in front of me, you can see the Lower Equipment Bay with the guidance and navigation panel that John works all the time to determine our position and attitude.
173:32:10 Duke: There's old one-eye. We got him.
173:32:21 Young: There's really not much difference today, is there?
173:32:40 Cernan: John likes to play in here. Every time he gets something in his hand, he has to do something different to it.
173:32:46 Stafford: How's the color coming in now, Charlie? Over.
173:32:49 Duke: Roger. The interior colors are fine. Little greenish tints, but I think that's a problem we got, Tom, with our converter here in building 30. The exterior also had a - quite a greenish tinge to it. It's better than the black and white. The black and white has a lot better definition, however, though.
173:33:12 Stafford: OK. We'll take you outside now and show how the Earth looks today. It's starting to get bigger as we approach 100,000 miles [185,200 km].
173:33:20 Duke: Roger. We'll stand by for your commentary.
173:33:46 Cernan: Charlie, we'll have it in a minute, and it's just coming right over the window edge. Here it comes now.
173:33:52 Duke: Roger. We have it, 10. Out.
173:34:11 Duke: OK, 10...
173:34:12 Stafford: OK. Again as you look at the - pardon me Again as you look at the Earth, it's upside down, so to keep all of you from standing on your heads, we'll just turn the camera upside down for the convenience of your viewing pleasure here.
173:34:26 Cernan: Charlie, we'll be looking at - at the east coast of - of the United States. Primarily down from - off the tip of Florida. Actually to us here we can see the Grand Bahama Banks. You can see the color changes in the water. You can see most of Florida. It looks like almost all the Gulf of Mexico is extremely clear. The Gulf Coast of the United States, Florida, Alabama, Mississippi, Louisiana, on down through Texas all looks clear. We can look on across from Houston all the way into the San Joaquin Valley, all the way into the Los Angeles area coming over the horizon into Baja California.
173:35:15 Cernan: We're vertically right now above the Earth, somewhere between Caracas and Panama. Charlie, how does the TV look to you down there?
173:35:27 Duke: Roger, 10. It's looking real good. Black and white is excellent. Definition of color is coming through on the commercial real fine. Our vidicon here on the big screen has got a lot of greens to it, but on commercially, it's looking great. Over.
It's likely that Duke is referring to a commercial TV set nearby as providing a good colour rendition, and that their large display, what Duke is referring to as the vidicon but actually called an Eidophor, is less that ideally adjusted. In the days of analogue television, it was a constant task to keep the three colour signals, red, green and blue, properly aligned.
173:35:47 Cernan: Is it saturating right now?
173:35:51 Duke: Negative. Only in the North Pole area where the cloud banks are pretty heavy, and then only partially up there so - We've got one clear spot up towards the Arctic Circle that we can't figure out what it is. Could you give us a little run-down on that? Over.
173:36:10 Stafford: OK. Wait just a minute. It's starting to disappear out the left hatch window, and John will take the camera there and go right and take it out through our center hatch window. And here you can see the Earth as it starts to go out the left side window.
173:36:24 Duke: Roger.
173:36:37 Duke: 10, Houston. We got just 30 seconds left on the High Gain on this pass.
173:36:47 Cernan: Looks like we won't catch you this time, Charlie, but that big low-pressure cloud so very distinctive over the Alaskan area, Aleutian area is very distinctive to us with the naked eye. We can't quite get it for you out the hatch window at this time, as we're going.
173:37:06 Duke: Roger. We'll stand by then. We got about 20 seconds left or so and if you want to show us, it will be - Standby. Eight more minutes and we'll have the High Gain back, if you want to keep the camera up. Over.
173:37:34 Stafford: OK. We just wanted to get a - show you how things are going aboard Apollo 10 today. So after shaving we all feel refreshed. In fact, we feel just great up here, and looking forward to splashdown tomorrow. We got about 100,000 miles [185,200 km] more to go, but we really pick up the majority of it in the last few hours. Over.
173:37:55 Duke: Roger, 10. We copy. Thank you very much for the show. Over.
173:37:58 Duration of that transmission was 10 minutes, 22 seconds. And Apollo 10's distance is now 98,650 nautical miles [182,700 km]. Velocity, 6,558 feet per second [1,999 m/s].
173:38:02 Stafford: Roger. And we just wanted again to show you the relative size of the Moon and the Earth today, as we see it here nearly equidistant between the two, about 110,000 miles [204,000 km] from the Moon and 100,000 miles [185,200 km] from the Earth. And we'll see you tomorrow. Over.
173:38:17 Duke: Roger. Thank you much again, 10, for the show. See you later. Out.
173:40:01 Cernan: Houston, this is 10.
173:40:03 Duke: Go ahead.
173:40:06 Cernan: For my own long-range planning, do you anticipate bringing fuel cell 1 up once more tomorrow, prior to entry?
173:40:16 Duke: Stand by, Gene.
173:41:36 Duke: Apollo 10, Houston. We don't plan to bring fuel cell 1 back on the line for the rest of the flight. And we got your E-memory dump and it's Go. No mistakes after 7 days. And on your entry checklist, we got a couple of minor changes if you'd like to break that book out, and we'll talk to you about it. Over.
173:42:11 Stafford: OK. Stand by.
173:43:50 Stafford: Hello, Houston. Apollo 10. Go ahead on that entry checklist. Over.
173:43:55 Duke: Roger, 10. We'd like on page 2.2 correction 2.2 step 6, about the middle of the page; we say, "fuel cell 2 main A and B Off." We'd like to change that, of course, to fuel cell 1. Over.
173:44:22 Stafford: OK. John's got it in now, fuel cell 1 main A and main B.
173:44:27 Duke: Roger. And we'd like to - We're going to have to reservice the primary Evap before we bring it on the line. So you could just pencil that in. And that will be done at about minus 1 hour, when we manually bring it on the line. Over.
The primary evaporator in the Environmental Control System began operation soon after lift-off but dried out after only a few minutes. It was reserviced just prior to LOI, and again dried out after a couple of hours operation. It would preferable to have both the primary and secondary evaporators available during re-entry, although either one would suffice.
173:44:47 Young: Roger. I'd like to get the servicing of it done a little sooner, if that's possible. Over.
173:44:50 Duke: OK. Stand by.
173:45:16 Duke: 10, Houston. It's your choice on where you insert the servicing of that Evap - 3, 4, or 5 hours, anywhere around in there is OK with us. And we'd like you to service it for 3 minutes. And final thing is, due to the problem that we've had with this Evap, they'd like to run some altitude tests on it after we get it back to Downey. And, Gene-o, if you have time, on the - after the mains, if you could close back pressure valves on both the secondary and the primary, they would appreciate it. However, it's not a mandatory call. Over.
So that post mission analysis of the evaporators can be carried out at North American, the CSM manufacturers in Downey, California, MCC-H are requesting that following the deployment of the main parachutes, the crew close the back pressure valves on both evaporators. To do so on the Primary Evaporator, the Glycol Evap, Steam Press switch should be moved to the 'Man' position, for the Secondary Evaporator, Sec Coolant Loop, Evap switch should be moved to the Reset position.
Glycol Evap, Steam Press switch and Sec Coolant Loop, Evap switch - CM panel 2.
173:45:58 Cernan: OK. That - that [garble].
173:46:23 Duke: Hello, 10. Houston. We're now on the High Gain. Did you copy my last, about the back pressure valves? Over.
173:46:30 Cernan: Yes. I did, Charlie. I'll give it a go on both of them after we get on the mains.
173:46:33 Duke: Roger. That's all we had on the entry checklist at this point. Out.
173:46:39 Young: OK, Charlie. We want to service the evaporator right around 2 hours, if that's OK, right with the logic sequence check.
173:46:46 Duke: That's fine, John.
173:47:07 Young: And, Charlie, how important is it to get the secondary evaporator serviced - to get the evaporator serviced and running? If it doesn't come up, we'll just go without it like 8 did, won't we?
The Primary Evaporator on Apollo 8 dried out during the early lunar orbits, took two attempts to reservice and again dried out during re-entry. After drying out during re-entry, there was no opportunity to reservice it, so the remainder of the descent replied on the Secondary Evaporator. Young is making the point that a single evaporator is sufficient, but it would be preferable to have both evaporators operating.
173:47:17 Duke: Stand by. That's affirmative.
173:47:24 Young: OK. Is this just to find out if it will run?
173:47:31 Duke: That's essentially correct, John. We'll have some more words on it for you, in a little bit.
Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.
173:49:33 Duke: Hello, Apollo 10. Houston. We've had second thoughts on the fuel cell. We'd like you to bring it on for the midcourse, and we'll let you know. If we didn't bring it on, it would die out on us at about 180 hours and we don't want to do that. We'd like to keep it for - until SEP. So, we'll give you a minimum time around the midcourse to have it on. Over.
Duke is referring to the malfunctioning fuel cell 1.
174:00:26 McCandless: Apollo 10, this is Houston. Over.
174:00:31 Stafford: Roger, Houston. This is 10. We're standing by to set up the optics calibration at this time. Over.
174:00:37 McCandless: Roger. Since we've slipped the midcourse correction number 6 about 30 minutes, to roughly 177:20, we suggest that you stay in PTC for about another one-half hour and slip your P23 by half an hour, to something on the order of 174:50, commencement or thereabouts. Over.
174:01:09 Stafford: Houston. We're all configured for it, and John's getting pretty weary of making all these sights; and we want to go ahead and get it over with. Over.
Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.
This is Apollo Control at 174 hours, 20 minutes. Apollo 10 is 96,025 nautical miles [177,838 km] from Earth. Velocity is 6,649 feet per second [2,027 m/s] and we're about 3 hours away from the midcourse correction burn.
174:27:45 Engle: Boy, look at that one.
174:27:49 Stafford: Yes. John's put it right on the money.
Comm break.
Mission audio not available until 176:27.
174:35:40 Young: OK, Houston. That completes the sightings.
174:35:44 McCandless: All right, 10. This is Houston. Roger. We copy. And for your information, our latest analysis on fuel cell number 1 shows that it will not be necessary to bring it back on the line at all prior to separation from the service module; and if this changes, we will keep you posted.
174:36:08 Young: Roger. [Pause.]
174:36:13 Young: What's your...
174:36:27 McCandless: Apollo 10, this is Houston. Go ahead. Over.
174:36:30 Young: Roger. What's the best burn time you got now?
This is Apollo Control at 174 hours, 44 minutes. Apollo 10's distance from the Earth now at 94,434 nautical miles [174,892 km], approaching at a velocity of 6,706 feet per second [2,044 m/s]. Showing weight; 25,200 pounds [11,430 kg].
174:47:10 Young: OK, Houston. You saw our P37 numbers. What do you think?
174:47:16 McCandless: Roger. We're comparing them with our solution for Min Delta-V [garble] center of the corridor, Also Over.
174:47:24 Young: Well, just offhand, why don't we burn yours?
174:47:29 McCandless: OK.
174:47:58 Young: It didn't really look like it was big enough to get us in trouble, whether it was right or wrong.
174:48:03 McCandless: Roger. Out.
Very long comm break.
175:05:52 McCandless: Apollo 10, this is Houston. Over.
175:05:56 Stafford: Go ahead.
175:05:58 McCandless: Roger. The pressure decrease in your hydrogen Cryo tank continues. We are expecting you to get a master caution warning light at about 175 hours, 30 minutes, due to low pressure in the hydrogen tank. We would like you to just punch this out and let the pressure continue to decrease, and we'll set you up in configuration for this evening, based on that lower pressure and building it up overnight. Over.
175:06:30 Stafford: OK. Apollo 10. Over.
Very long comm break.
175:17:31 Stafford: Houston, Apollo 10. How does it look now to start the PTC? Over.
175:17:38 McCandless: Roger. You can go ahead and start the PTC now.
Comm break.
175:23:11 McCandless: Apollo 10, this is Houston. When you are ready to copy, I have your PAD for midcourse correction number 6.
175:23:23 Young: Roger. Just a second. OK. Go ahead.
175:23:29 McCandless: Roger. Midcourse correction 6, RCS/G&N: 25200, pitch and yaw trim not applicable. Noun 33 stuff: 177:19:58.00; plus 00010, plus all balls, plus all balls; roll 088, 354, 350; HA not applicable, plus 00210; 00010, 004, 00010; sextant star 40, 275.6 33.8; boresight star 033, up 007, left 13; GDC align Vega 36, Deneb 43; roll align 148, 013, 018. This will be a two-quad burn, use Bravo and Delta. Remarks: Go with the onboard entry PAD. If you have - it's still valid. Read back. Over.
175:25:43 Cernan: OK, Bruce. MCC 6. RCS/G&N: 25200, 48 is NA; 177:19:58.00; plus 00010, plus all balls, plus all balls; 088, 354, 350; apogee is NA, perigee is plus 00210; 00010, 004, three balls 10; sextant star is 40, 275.6, 33.8; 033, up 007, left 13, Vega 36, Deneb 43; 148, 013, 018. Using two quads, Bravo and Delta. And our onboard entry PAD is still good.
The P30 PAD is interpreted as follows:
Purpose: This PAD is for midcourse correction 6 to fine turn the re-entry trajectory.
Systems: The manoeuvre will be made using the SM RCS under the control of the Guidance and Navigation system.
CSM Weight (Noun 47): 25,200 pounds (11,430 kg).
Time of ignition, TIG (Noun 33): 177 hours, 19 minutes, 58.00 seconds.
Change in velocity (Noun 81), fps (m/s): X, +0001.0 (0.3) Y, +0000.0 (0.0); Z, +0000.0 (0.0).
Spacecraft attitude: Roll, 88°; Pitch, 354°; Yaw, 350°. The desired spacecraft attitude is measured relative to the alignment of the guidance platform.
HA, expected apogee of resulting orbit (Noun 44): Not applicable. The trajectory being modified has no sensible apogee, at least in terms of the computer.
HP, expected perigee of resulting orbit (Noun 44): 21.0 nautical miles (39 km). This will their altitude at closest approach according to the trajectory resulting from this burn. When they reach this point, they will make their first LOI burn to place them into lunar orbit.
Delta-VT: 1.0 fps (0.3 m/s). This is the total change in velocity the spacecraft would experience. (It is a vector sum of the three components given above.)
Burn duration or burn time: 4 seconds.
Delta-VC: 1.0 fps (0.3 m/s). This value is entered into the Delta-V display of the EMS (Entry Monitor System) panel. They will watch this figure descend to zero as the RCS fires, giving them a confirmation of the burn's progress.
Sextant star: Star 40 (Altair) visible in sextant when shaft and trunnion angles are 275.6° and 33.8° respectively. This is part of an attitude check.
Boresight star: 033 (This may refer to Antares (33 on the Apollo star list) but the leading zero gives us pause to wonder.) This star is used to check the spacecraft attitude through the COAS. up 0.7° COAS bore-sight star pitch angle, and left 1.3° X position on COAS.
GDC Align stars: Stars to be used for GDC Align purposes are Deneb and Vega. This would be used in the event that the IMU could not be used for aligning the gyro assemblies. The spacecraft would be manoeuvred so that the two stars could be viewed in the scanning telescope in a certain configuration. On achieving this, the spacecraft would be in a known attitude, the same one given in the PAD, allowing the GDC to be manually aligned.
An additional note is that this manoeuvre will use two RCS quads, Bravo and Delta.
175:26:38 McCandless: 10, this is Houston. Readback correct. Out.
175:27:00 McCandless: 10, this is Houston. If you'll go to Accept on your up telemetry, we'll give you a new state vector and target load. Over.
175:27:15 Cernan: OK. We're going to Accept.
175:27:18 McCandless: Roger. Out.
175:27:50 Cernan: Houston.
175:27:51 Cernan: Mark.
175:27:52 Cernan: We just got the Cryo pressure light.
The Cryo Press caution and warning light on panel 2, has illuminated due to the pressure in one of the H2 storage tanks has fallen below 220 psia.
175:27:55 McCandless: Roger.
Comm break.
175:31:48 McCandless: Apollo 10, this is Houston. We've completed the uplink. The computer is yours again, You can go to Block.
175:31:59 Young: Thank you.
175:32:03 McCandless: Roger. Out.
Long comm break.
This is Apollo Control at 175 hours, 32 minutes. Apollo 10 is 91,316 nautical miles [169,117 km] from the Earth. Velocity is 6,820 feet per second [2,079 km]. We're a minute - an hour, 46½ minutes away from the midcourse correction. Time for that midcourse burn; 177 hours, 19 minutes, 58 seconds. Will be done with the Reaction Control System, 2 quads of that system, Delta-V of 1 foot per second (0.68 m/s), duration of the burn will be 4 seconds, and the spacecraft will be oriented out of plane to the east during that very short burn.
This is Apollo Control at 176 hours. Apollo 10 is 89,458 nautical miles [165,676 km] from the Earth approaching a velocity of 6,891 feet per second [2,100 m/s]. We're an hour and 18 minutes away from the midcourse correction.
AS10-27-3981 - View of Earth showing North America and the Central American isthmus on the terminator - Image by NASA/ASU.
176:08:30 Stafford: Hello, Houston. Apollo 10.
176:08:33 McCandless: Apollo 10, this is Houston. Go ahead.
176:08:35 Stafford: Roger. Have you loaded P30 in the last uplink? Over.
176:08:46 McCandless: That's affirmative. You had a target load and a state vector in the last uplink. Over.
Program 30 is the External Delta V program. It allows the AGC to accept a target load from MCC-H for upcoming manuevers. The target load provides the time of ignition and the Delta-V along the CSM local vertical axes at ignition.
176:08:54 Stafford: OK. Thank you.
176:09:04 Stafford: We'll go ahead and go through P30 at this time. Over.
176:09:09 McCandless: Roger. And for John's information, based on the resultant of his P23 Marks, we ran the data in our computer and got the same Delta-V resultant out as you did on board using P37. Over.
176:09:32 Young: I figured you would.
176:09:35 McCandless: Roger. We just wanted to run it through the same thorough routine, and give you confirmation that the routine you've got was working.
176:09:44 Young: OK. Thank you kindly.
176:09:46 McCandless: Roger. Out.
176:11:23 Stafford: OK, Houston. We've gone through P30. It looks good here. Over.
Very long comm break.
Using the target load provided by MCC-H, the crew can run program 30 to establish the resultant orbital parameters, the magnitude of the Delta-V, the time from ignition to the planned manoeuvre, and the middle gimbal angle at ignition, when the vehicles +X axis is in the direction of thrust. The crew have run the program to gain reassurance that the resultant parameters are satisfactory for the upcoming MCC-7.
176:11:31 McCandless: Houston. Roger. Out.
AS10-27-3982 - View of Earth showing North America and the Central American isthmus on the terminator - Image by NASA/ASU.
AS10-27-3983 - View of Earth showing North America and the Central American isthmus on the terminator - Image by NASA/ASU.
This is Apollo Control at 176 hours, 21 minutes. Apollo 10's distance from the Earth is 88,011 nautical miles [162,996 km]. Velocity 6,948 feet per second [2,118 m/s].
Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.
176:30:17 Young: Houston, were going into our REFSMMAT Realign now.
176:30:21 McCandless: This is Houston. Roger. Out.
Long comm break.
176:37:16 McCandless: Apollo 10, this is Houston. Over
176:37:20 Stafford: Houston, go ahead.
176:37:23 McCandless: Roger, 10. We'd like to make a correction to our scheduled midcourse correction plan of operations here, by canceling midcourse correction number 6 and definitely having midcourse correction 7. A little background on this is that with the long fuel cell purge and the secondary evaporator checkout, the tracking still hasn't stabilized to the point where we can give you a midcourse correction number 6 and be confident 100 percent that midcourse 7 will not be required. And if there is a possibility of having to burn 7, the tracking people would like to consider - would like to continue their tracking without the perturbation caused by midcourse correction 6. For your information, you're still well within the corridor. These burns were in the form of tweaking, to get you in the center of the corridor, We anticipate a Delta-V for midcourse correction 7 on the order of 3 to 4 feet per second, at the nominal time in the Flight Plan. Over.
Remembering that this is only the second manned translunar mission, MCC-H are keen to ensure that they obtain the best quality tracking to ensure that the best data is available to calculate the parameters of any required midcourse correction. They want to take the extra time that is available to them to fine tune the tracking data.
176:38:36 Stafford: OK. Roger. Stand by.
176:38:40 McCandless: Roger.
176:38:57 Stafford: Roger. Houston, Apollo 10. That's what we practiced all along in the simulator, so it really doesn't matter to us one way or the other. We can sure do it. Over.
176:39:06 McCandless: Roger,10. Then we'll go with not burning 6 and definitely planning on having a midcourse correction 7, at 188:50 GET.
176:39:17 Stafford: At 188:50. OK.
176:39:21 McCandless: Roger. As nominal.
176:39:24 Stafford: Roger.
176:40:40 Stafford: Apollo 10 is going back to the PTC mode. Over.
176:40:45 McCandless: 10, this is Houston. Roger. Out.
176:44:21 Young: You're definitely getting larger in diameter there, Earth.
176:44:29 McCandless: Roger. We understand you see us growing larger. We can't see you yet with the naked eye, but hope to tomorrow. We're showing you about 90,000 miles [166,700 km] out at the present time.
176:44:46 Stafford: Roger. Got a beautiful view here of the Earth. It seems like there is a little - from here like a cumulus thunderstorm up on the cloud cover that covers up near the polar ice cap. It really is beautiful, the way it stands out. We got a couple of pictures of it. Over.
176:45:00 McCandless: Roger. Out.
176:45:53 Stafford: Hello, Houston. Apollo 10. Can you check and see at what GET should we hit night time just before we approach the Entry Interface? Over.
176:46:04 McCandless: Roger. Stand by a second.
176:46:37 McCandless: Apollo 10, this is Houston. Time of local sunset will be 191:19:51 GET. Over.
176:46:52 Stafford: Roger. Could you say again, Bruce, please?
176:47:04 Stafford: Roger. Copy. Sunset at 191:19:51.
Comm break.
As the spacecraft approaches Earth, it will pass through the planet's shadow. This is the time that they enter that shadow. The crew of Apollo 12 found the view of Earth to be particularly captivating when they flew through its shadow. This was greatly helped by the Earth/Moon/Sun geometry at the time that meant that the night-time Earth was being illuminated by a full Moon.
176:49:17 Young: Houston, this is Apollo 10. Over.
176:49:20 McCandless: Go ahead, 10. We can hear you over the jukebox.
176:49:27 Young: OK. Would it be OK to run P37 through, taking your midcourse 7 time and see what we come up with? With this state vector we've got now?
Program 37 is used to calculate the return to Earth trajectory. The astronauts provide the time of ignition, Delta-V and the specified re-entry angle. The program will provide the time from the manoeuvre ignition until re-entry, the re-entry inertial velocity, the resultant re-entry flight path angle, latitude and longitude of the splashdown, and the manoeuvre Delta-V. If the resultant parameters are accepted by the crew, they are stored for use by program 41 when using the SM RCS for the mid-course manoeuvre.
176:50:02 McCandless: Apollo 10, this is Houston. Affirmative, and we'll run it down here, too. We can compare results if you like. Over.
176:50:10 Young: Rog.
Comm break.
AS10-27-3984 - View of Earth showing the western part of North America on the terminator - Image by NASA/ASU.
AS10-27-3985 - View of Earth showing the western part of North America on the terminator - Image by NASA/ASU.
Clip courtesy John Stoll, ACR Senior Technician at NASA Johnson.
176:58:35 McCandless: Apollo 10, this is Houston. Over.
176:58:40 Stafford: Houston, go ahead.
176:58:42 McCandless: Roger. Using your vector and our machinery, we came up with burn of 2.2 feet per second [0.67 m/s] in X, 0 in Y, and minus 0.1 [fps, 0.03 m/s] in Z, compared with the observed calculations you had onboard of plus 2.50 [fps, 0.76 m/s] and minus 0.1 [fps, 0.03 m/s]. Over.
176:59:06 Stafford: Roger.
176:59:09 Young: Ours plus, 2.5 and minus 0.1.
176:59:13 McCandless: Roger. That's what we saw on the DSKY. We got 2.2.
176:59:22 Young: What's the matter with your machinery down there?
176:59:38 McCandless: Yes. We've got one problem down here right now. There's a rumor going around that by stepping outside the Mission Control building, we can see you all with the naked eye. So a lot of us are out there looking.
176:59:53 Young: Did the machine go out there, too?
176:59:53 Stafford: We can see that the terminator is just passing over Houston right now.
177:00:01 McCandless: Roger. I believe that, but I haven't been outside in a couple of hours.
177:00:06 Cernan: Did somebody really see us out there?
177:00:10 McCandless: That's the report. Charlie is out there looking right now, and we expect to have an eyewitness account in a minute or so.
177:00:17 Cernan: I don't know what direction, but I would expect you would look to the southwest.
177:00:21 Stafford: Yes. From our angle, Bruce, where we are looking at you, I would say to the southwest. We're up at an angle of at least 45 or 50 degrees. Over.
177:00:33 McCandless: Roger.
177:00:34 Young: Anybody can see something 30 feet long [9 meters] at 90,000 miles [167,000 km] has really got the eyeballs.
177:01:09 Stafford: Hello, Houston. Apollo 10. Over.
177:01:12 McCandless: Go ahead, 10.
177:01:13 Stafford: Roger. I'm sure you saw the TV pictures the other day when we left the Moon straight away? Over.
177:01:19 McCandless: Right.
177:01:21 Stafford: OK. Well, right now it looks like we are just doing a reverse process, only we are heading straight for the center of the Earth above, but we all know that we're going to be entering west to east at a gamma of 6.5, don't we?
177:01:35 McCandless: Roger. We're working on that one, Tom.
177:01:39 Stafford: [Laughing.] OK.
Stafford is laughing at McCandless teasing that MCC-H are trying to come up with a trajectory that will take them to the nominal re-entry corridor, rather than the near vertical trajectory that seems apparent to the crew from their observations.
177:01:43 Cernan: Sure hope that is a problem you've solve.
177:01:59 Stafford: Bruce, from this position, it looks like we're going to hit oh, just down below Baja California, going straight in. Just watching the way it is slowly growing here. Over.
177:02:11 McCandless: Roger. Let me get you a current Entry Interface angle here.
177:02:16 Stafford: Oh, no. No problem. We're just kidding about that. It's really funny to watch. It's just a reverse process of after we started to climb out from the Moon the other day. Over.
177:02:25 McCandless: Roger.
177:02:39 McCandless: Right now, 10, we're showing an Entry Interface angle of approximately minus 6.8 degrees. Over.
177:02:48 Stafford: Roger. That sounds real decent. Thank you.
177:02:59 Stafford: Houston, Apollo 10. Are the FIDO's pretty well squared away with our c.g., and where we are stowing things? Over.
177:03:20 McCandless: Roger, 10. We're in good shape down here on the stowage and c.g.
177:03:27 Stafford: OK. Real fine. Thank you.
CG is centre of gravity, more meaningfully called centre of mass.
177:03:28 Cernan: We haven't yet told you where we are going to stow the canister, because we're not sure. We are probably going to wrap it up at the base of one of the suits. We'll have to let you know that.
Cernan is referring to the LM LiOH canister that didn't perform as expected during the LM solo operations, so they are returning it to Earth for further analysis. It is quite a bulky item, so secure storage during re-entry is important.
177:03:42 McCandless: OK. The last word I had on the canister was wrap it up in sleeping bag number 3 when you got through using it, and - let's see, you said that food compartment L3 still had food in it, I guess?
177:03:57 Stafford: Roger. You can tell the FIDO's that food compartment L2 and L3 all have - the ones here on the left - L2 and L3 are completely - no, I guess just L3 is just about completely filled with food, and our waste and one helmet is in B1 now.
177:04:26 McCandless: Say again what you got in B1 besides helmets, please.
177:04:30 Stafford: Just waste wrappings from the food packs. There was one helmet in there and just the waste wrappings from food. Couldn't be over a couple of pounds.
177:04:44 McCandless: Roger. So, when you all find a stowage location for the lithium hydroxide canister, if you'll pass it down to us, we'll crank it in.
177:05:00 Stafford: OK.
177:05:14 Stafford: Houston, Apollo 10. Do the rates look good to start the PTC? Over.
177:06:00 McCandless: 10, this is Houston. I'm afraid that report we got on visual observations of you earlier was erroneous. I think it was a planet over there.
177:06:10 Stafford: Roger.
177:06:12 Young: Roger. I was going to recommend about a 20-power telescope. Maybe 40.
This is Apollo Control at 177 hours, 6 minutes. Apollo 10's distance from the Earth is 84,986 nautical miles [157,394 km], velocity 7,071 feet per second [2,155 m/s].
Long comm break.
177:09:52 Stafford: OK, Houston. Apollo 10. We're going to start through the presleep checklist. We're going to purge the fuel cells, make the canister changes. Over.
177:10:10 McCandless: Apollo 10, this is Houston. Would you hold off on the fuel cell purge? You can proceed with the other items at the present time.
177:10:17 Stafford: OK.
177:10:18 Cernan: OK. Can I take the battery charge off?
177:11:05 Cernan: Hello, Houston. Will you give me a hack on when you want to start that fuel cell purge, and also do you desire to stay High Gain tonight?
177:11:22 McCandless: Roger. We'll give you the word on the fuel cells here in a minute.
177:11:42 Stafford: Houston, Apollo 10. Are you ready to copy the CM RCS thruster temps? Over.
177:11:47 McCandless: Roger. Send your message, 10.
177:11:51 Stafford: Roger. 5C is 5.1, 5D is 5.1, 6 Alpha is 5.1, 6 Bravo 5.1, 6 Charlie is 4.0, 6 Dog is 4.6. Over.
Using the systems test meter on panel 101, the crew can select various hardware parameters. The crew are reading off the CM RCS oxidizer valve temperatures, as follows:
5C - -pitch on system B reading of 5.1 translates to 52°F (11.1°C)
5D - +yaw on system B reading of 5.1 translates to 52°F (11.1°C)
6A - counter clockwise roll on system A reading of 5.1 translates to 52°F (11.1°C)
6B - -pitch on system A reading of 5.1 translates to 52°F (11.1°C)
6C - -yaw on system A reading of 4.0 translates to 30°F (-1.1°C)
6D - clockwise roll on system B reading of 4.6 translates to 42°F (5.6°C)]
177:12:12 McCandless: Roger. We copy; And the S-band operations this evening will be Omni. Request you select Omni Bravo and Omni on board, and we'll do the switching from down here.
177:12:25 Cernan: Okey doke. Going Omni at this time.
177:12:58 McCandless: Apollo 10, this is Houston. You can proceed with the oxygen purge on fuel cells 2 and 3. Over.
177:13:07 Cernan: Roger.
177:13:46 Stafford: OK, Houston. Apollo 10. We're ready for some onboard readouts on the batteries and RCS. Over.
177:13:54 McCandless: Roger, 10. Press on.
177:14:06 McCandless: Apollo 10, this is Houston. Go ahead with your onboard readouts.
177:14:09 Stafford: Roger, Bruce. Batt C is 36.8 [VDC], Pyro Batt A is 36.8 [VDC], Pyro Batt B is 36.8 [VDC]. RCS A 53 percent, RCS B 65 percent, C is 65 percent, and D is 60 percent. Over.
177:14:30 McCandless: Roger, 10. We copied.
177:15:40 Stafford: Houston, Apollo 10. Over.
177:15:42 McCandless: Go ahead, Apollo 10.
177:15:43 Stafford: All right. Looking forward to tomorrow morning, we don't want to miss the major events; and so, what we'd like to have you do is wake us up about an hour earlier since we're going to hit the sack a little earlier tonight. We would like to have you wake us up at a GET of 85 hours. Over.
177:16:03 Stafford: That is, 185.
177:16:06 McCandless: Roger. We'll wake you up at GET of 185 hours.
177:16:11 Stafford: Roger. You can put a call into the desk and just have them wake us up with some soft music, please.
177:16:36 Cernan: And, Bruce, put in an order for sausage and eggs, too, would you please?
177:16:45 McCandless: I suggest you hold off on those until lunch time.
177:16:50 Stafford: OK. We'll try to. [Long pause.]
177:17:37 McCandless: Apollo 10, this is Houston. Over.
177:17:44 Stafford: Go ahead, Houston.
177:17:47 McCandless: Roger. I've got your Cryo tank configuration for the night.
177:17:53 Stafford: OK. Stand by 1 second. We'll get it.
177:17:55 Slayton: Sounds like things are lively up there in the malt shop tonight.
177:18:10 Stafford: Hello there, Deke. Yes, we're just taking things easy here and relaxing and going through the total program for tomorrow morning. In fact, we've gone through the checklist a couple of times and rebriefed it; so we're just taking it easy, watching the scene outside; which is beautiful, and listening to some music. Over.
177:18:27 Slayton: Roger. That's great.
177:18:33 Stafford: Yes. Did you hear me tell Bruce what our impression was of coming back to the Earth, how it looks just about opposite of going away from the Moon? Over.
177:18:40 Slayton: Roger.
177:18:44 Young: Boy, this is really something, Deke.
177:18:48 Slayton: That last couple of hours is going to be the bear.
177:18:53 Young: Yes.
177:18:56 Stafford: Now, from this angle it looks like we're going to just approach the Earth here at a gamma of about 90 degrees. [Laughing.]
Stafford is jokingly suggesting that from their current observation, it looks like the re-entry angle will be near vertical.
177:19:10 Slayton: Yes. We indicate about 78.
177:19:16 Stafford: [Laughing.] Oh, that's great.
177:19:20 Cernan: That food's getting to you.
177:20:05 Cernan: OK, Houston. I'm ready for the Cryo fan. If you want to go right down the panel, I'll configure it.
177:20:11 McCandless:. OK. I'll just run down the row of switches here. H2 heaters: 1 Off, 2 Off. O2 heaters: 1 Off, 2 Auto. H2 fans: 1 ON, 2 Off. O2 fans: Off, Off. Over.
177:20:50 Cernan: OK. I got heaters: H2 1 is Off, 2 is Off; O2 1 is Off, and 2 is Auto. On the fans: H2, I've got 1 ON, 2 Off; O2 fans, 1 Off and 2 Off.
177:21:10 McCandless: Roger. Readback correct. I think you're properly configured for the evening.
177:21:18 Cernan: Thank you.
177:22:04 This is Apollo Control estimating the change of shift news conference for 9:30 pm central daylight time.
177:33:20 Stafford: Roger, Houston. This is 10. We're going to go ahead and sack out at this time. Over.
177:33:24 McCandless: Roger. Can you give us a crew status report prior to turning in?
177:33:32 Stafford: Oh, we'd be glad to do that, Houston.
177:33:35 McCandless: Roger. They're interested in getting a hack on the - the radiation now, and then after you get back down through the Van Allen Belt.
This being only the second manned translunar mission, the radiation readings taken are extremely important to get an understanding of the exposure received as they pass through the Earth's Van Allen belt.
177:33:44 Stafford: Roger.
177:35:48 Cernan: Hello, Houston. This is 10.
177:35:49 McCandless: Roger. Go ahead, 10.
177:35:52 Cernan: OK. The CDR is 26048, the CMP is 05048, and the LMP is 15049.
177:36:05 McCandless: Roger. We copy the PRDs.
177:36:08 Cernan: And, we've never seen, on any of the checks we've ever taken, either in here or in the LM, anything more than about 0.001 off of the meter.
177:36:18 McCandless: Roger. Copy. Nothing more than 0.001 on the meter.
177:36:31 Cernan: Well, maybe that scale is 0.01, Bruce, but it's on the 0.1 scale and it's barely readable. Barely above zero. I guess it's 0.01.
177:36:39 McCandless: Roger. Barely readable on the1 tenth scale.
177:36:43 Cernan: I take it back. It is 0.001 is the highest we've ever seen anywhere.
177:36:44 McCandless: Roger. Copy 1, one thousandth.
177:37:14 McCandless: OK, Apollo 10. This is Houston. The Black Team is signing off here. On behalf of everybody in the MOCR, we want to wish you a good night and a safe re-entry and happy landings, and we'll all see you on the ground when you get back.
177:37:31 Stafford: Roger, Houston. We just want to say thanks a lot to the whole team down there. There's been some fantastic support that we've had. We're going to come around and thank all of you personally, after we get back there to Houston. Over.
177:37:44 McCandless: Roger. And the Maroon Team is taking over now.
177:37:50 Stafford: Roger.
177:38:02 Young: Well done there, Black Team.
177:38:09 Cernan: And, thanks a lot, guys.
177:38:34 Engle: OK, 10. This is Houston. That big maroon got the eyeballs on you, so you guys hurry up every chance you get and get on home.
177:38:43 Cernan: We're on our way, Joe baby. You just keep alert tonight, keep us in the corridor, and we'll see you soon.
177:38:50 Engle: Roger that. Go get some huggy pillow. We'll keep our eyeballs on you.
177:38:56 Cernan: Some what?
177:39:00 Cernan: You ever spend the night in the command module?
177:39:04 Engle: Roger that.
177:39:10 Cernan: That's right, you did, and you know.
This is Apollo Control at 177 hours, 45 minutes, and we've completed the shift change here in control. The Maroon Team of flight controllers headed by Flight Director Milton Windler, has replaced the Black Team headed by Glynn Lunney, and our capsule communicator on this shift will be astronaut Joe Engle. You heard the crew advise that they would be turning in now, beginning their sleep period about 45 minutes early. They were able to do that because midcourse correction 6 which had been scheduled at 176 hours, 50 minutes has been deleted, and we intend to make that midcourse correction at the time planned for midcourse correction 7 which will come at 188 hours, 50 minutes. At the present time, Apollo 10 is 82,272 nautical miles [152,368 km] from Earth, and the velocity up now to 7,188 feet per second [2,191 m/s]. We don't expect a great deal of conversation out of the crew in the next hour or so as they complete preparations for their rest period, but we'll stand by. This is Apollo Control at 177 hours, 46 minutes.
Comm break.
This is Apollo Control at 178 hours, 19 minutes. During the change of shift briefing, we had one brief conversation with Gene Cernan. We now presume that the crew is attempting to get to sleep. We'll play back that short conversation for you now.
177:49:13 Cernan: Hello, Houston. Houston, this is Apollo 10. Over.
177:49:17 Engle: Roger, 10. Go ahead.
177:49:19 Cernan: OK, Joe. I just - We're just getting all configured. I got the duty. I just want to make sure that I can hear you in case I have to, and I guess I can.
177:49:27 Engle: OK. Mighty fine. Well, get a good night's sleep, and I'll see you in about 7 hours and 10 minutes or so.
177:49:33 Cernan: OK, babe. Listen, any - any news from the home front, Mike? At home or anything. Everything shipshape?
177:49:38 Engle: Just came from there. Yes, everything's ship shape. We just made a run on your table there on your patio, and I think I'm going to need a little more practice on that.
177:49:53 Cernan: Oh, man. There's - there's a few things you got to know about that one.
177:49:59 Engle: Well, I got the lesson from the expert.
177:50:02 Cernan: Oh, I believe it. I believe it. Listen, we'll try it when I get back. We'll see you, and I'll - If there's any question about calling, call, will you? And I'll see you tomorrow.
177:50:13 Engle: Righto, Buddy. OK. Good night.
177:50:18 Cernan: Good night.
AS10-27-3986 - View of Earth showing the Pacific Ocean - Image by NASA/ASU.
AS10-27-3987 - View of Earth showing the Pacific Ocean - Image by NASA/ASU.
At the present time Apollo 10 is 79,880 miles [147,938 km] from Earth and traveling at the speed of 7,295 feet per second [2,224 m/s]. At 178 hours, 20 minutes; this is Mission Control, Houston.
This is Apollo Control at 179 hours, 29 minutes. The Flight Surgeon reports that Gene Cernan, the one crewman on whom we have biomedical data tonight, appears to be sleeping at this time. The crew advised that at 177 hours, 40 minutes that the they were going to begin their rest period a little early, with the plan of getting up a early for tomorrow's re-entry activities. About 20 minutes after announcing that they planned to begin the sleep period, Cernan appeared to be sleeping. At the present time, Apollo 10 is 74,921 nautical miles [138,754 km] from Earth and the spacecraft is traveling at a speed of 7,531 feet per second [2,295 m/s]. During the night the Flight Dynamics Officer and the Return to Earth Officer on this shift will be actively involved in getting the trajectory data and burn data prepared for the midcourse correction number 7, the 7th midcourse correction opportunity which will actually turn out to be the first midcourse correction on route back from the Moon. And the current plan is to perform that maneuver at the normal time in the Flight Plan at 188 hours, 50 minutes Ground Elapsed Time. We estimate at this time that that would be about 1 foot per second [0.3 m/s] change in velocity, which of course would be performed with the reaction control system jets. At 179 hours, 31 minutes this is Mission Control, Houston.
