Apollo 16

This is Apollo Control, Houston, at 194 hours, 56 [194:44] minutes Ground Elapsed Time. We're less than a minute away now from reacquiring Apollo 16 now [on] its 62 - sixty second revolution. We show a little more [than] 13 minutes away now for time of Lunar Module jettison and this will be coming up on this frontside pass, and the Command and Service Module separation is scheduled some 5 minutes later. This is at 195 hours, 15 minutes Ground Elapsed Time. It will be [a] two foot per second retrograde burn. We'll stand by and await conversation with the crew of Apollo 16. At 194 hours, 57 minutes continuing to monitor, this is Apollo Control, Houston.

We're now receiving data from the spacecraft.

This is Apollo Control, Houston 195 hours, 9 minutes Ground Elapsed Time. Standing by now for word on LM jettison.

Mattingly working with his onboard computer now and Program 41, the RCS program.

Apollo Control, Houston. The loss of attitude control on Lunar Module Orion precludes the possibility of a targeted burn. A decision is still pending, whether a burn attempt should be made. Data makes it questionable as to whether or not it is possible, in fact. We're at 195 hours, 34 minutes ground elapsed time. This is Apollo Control Houston.

Apollo Control, Houston. Ken Mattingly reporting the Mass Spectrometer boom has been jettisoned. We're at 195 hours, 36 minutes [195:24] Ground Elapsed Time.

This is Apollo Control, Houston at 196 hours, 11 minutes Ground Elapsed Time. We've just had Loss of Signal with Apollo 16 now on its 62nd revolution around the Moon. Meanwhile in the Mission Control Center, we're in the process of a change of shift. Pete Franks' Orange Team of flight controllers coming aboard now. The Flight Director for the shift departing, Phil Shaffer. We're at 196 hours, 11 minutes Ground Elapsed Time, and this is Apollo Control, Houston.

This is Apollo Control at 197 hours, 10 minutes. During the change of shift briefing we reacquired Apollo 16. The Spacecraft [is] now in its 63rd revolution of the Moon. We expect this to be a relatively quiet front side pass. Among the things that we'll be reading up for the crew, will be the numbers that they will use, these will be preliminary numbers, for the Trans-Earth Injection maneuver. Which is to occur on the 65th revolution at about 200 hours, 33 minutes Ground Elapsed Time. Ken Mattingly is presently operating the cameras getting some pictures from the Command Module and also we'll have the Pan Camera operating during a portion of this front side pass. We have accumulated a small amount of taped conversation we'll replay that for you at this time and then continue to stand by live.

This is Apollo Control, that completes our tape playback we'll continue now to stand by live. Although we haven't gotten confirmation from the crew our telemetry data shows that the sub-satellite has been ejected, from the CSM, from the service module, the SIM bay. And we expect that we will be getting a confirmation from the crew on that also, however at the present time they are quite busy with the cameras on board. And we've been keeping the amount of conversation and the amount of request we've been making on the uplink to a minimum.

This is Apollo Control at 197 hours, 41 minutes [197:29]. Our Return to Earth Officer is in the process of computing a preliminary set of numbers for the Trans-Earth Injection maneuver, That maneuver will start Apollo 16 on its way back to Earth [and] is scheduled to start at 200 hours, 33 minutes [and] 20 seconds [200:21:30] Ground Elapsed Time. And the burn will be performed with the spacecraft Service Propulsion System engine will be about a 2 minute, 50 second maneuver. And with the completion of that burn a splashdown time will be set at 266 hours, 2 minutes [and] 7 seconds. That time is subject to change a little bit but the time of Entry Interface will be quite fixed once the Trans-Earth Injection maneuver has been performed. We also have some times for Acquisition of Signal with and without the Trans-Earth Injection maneuver. If the burn is performed as planned, the Acquisition of Signal time as Apollo 16 comes around from behind the Moon after performing the burn will be 200 hours, 43 minutes [and] 10 seconds [200:31:20]. If for some reason the burn is not performed as scheduled on the 65 revolution, the Acquisition of Signal time will be 200 hours, 52 minutes [and] 50 seconds [200:41:00]. Looking a little farther down the Flight Plan, the time now for Mid-Course Correction Number 5 is 217 hours, 34 minutes. And the time for the CSM EVA is 221 hours, 5 minutes. Correction on that the - yes, that would be hatch open [at] 221 hours, 5 minutes for hatch open, and hatch closed at 222 hours, 15 minutes. In Central Standard Time that would compute to 4:47 pm Central Standard Time the hatch open and 5:57 pm central standard time for the hatch closed. And again the splashdown time that we are looking toward is 266 hours, 2 minutes 7 seconds. We expect that that number will probably be updated somewhat following the Trans-Earth Injection maneuver. Apollo 16 at the present time is in an orbit with a high point or apocynthion of 66.5 nautical miles and a low point above the lunar surface of 52.4 nautical miles.

This is Apollo Control. We would like to point out that these numbers that were just passed along for such events as TEI, the Mid-Course Correction, the Trans-Earth EVA and splashdown all do not take into account the fact that we are expecting to do a clock update. That clock update will move the clock ahead about 21 hours [and] 50 minutes. That 21 hours [and] 50 minutes will have to be added to the times that we have given - to the GET times that we have given, in order to keep them in sync with the time we'll be using in Mission Control once the GET update has been done. We still haven't settled precisely on when that update will be made. The primary purpose for it is to bring the clocks into synchronization with the Flight Plan. At this point there are two things we can do. We can either go through the Flight Plan as we have been doing up to now and changing all of the times that are in the Flight Plan to make them agree with the clock or, and this is a more simple procedure, we can simply change the clock to make it agree with the times that are already in the Flight Plan. This eliminates a great deal of changes that have to be made to the Flight Plan and will be done at a convenient point. However, just when that point will be reached we haven't decided on yet. It will be sometime after the Trans-Earth Injection maneuver. The Central Standard Times, of course, are not affected and they will remain the same for the hatch open, hatch close. Again, that Central Standard Time for the Trans-Earth EVA hatch open is 4:47 pm Central Standard Time [and] hatch close 5:57 pm Central Standard Time. The playing that we do with the clocks here in the control center and on the spacecraft will not affect those Central Standard Times.

This is Apollo Control. We lost radio contact with Apollo 16 while John Young was in the process of reading back those numbers. The numbers that he was reading back to us are the preliminary numbers that will be used for the Trans-Earth Injection maneuver. That maneuver occurs at a Ground Elapsed Time of 200 hours, 33 minutes [and] 21 seconds. And, it will be performed using the spacecraft Service Propulsion System engine [and] the primary guidance and navigation system. It comes at the very end of the 64th revolution while the spacecraft is behind the Moon. We'll get our first report on the outcome of the maneuver as the spacecraft comes into acquisition on the 65th revolution of the Moon. The total velocity change is predicted at this point to be 3,371 feet per second and that will be achieved by burning the Service Propulsion System engine for 2 minutes, 42 seconds. With that burn performed nominally we would predict a time of entry interface of 265 hours, 49 minutes [and] 12 seconds leading us to that splashdown time of 266 hours, 2 minutes [and] 7 seconds. The amount of time the spacecraft spends on the chutes after entry interface seems to be a little bit more variable than the time of entry interface. But, those times should not change a great deal given a nominal SPS Trans-Earth Injection maneuver. We'll be reacquiring Apollo 16 in 42 minutes as the spacecraft went around the corner of the Moon we were showing an orbit of 66.6 nautical miles by 52.6. At 198 hours, 11 minutes; this is Apollo Control, Houston.

This is Apollo Control at 198 hours 54 minutes. And we have just reacquired Apollo 16 now in its 64th revolution of the Moon, this will be the last complete orbit of the Moon that Apollo 16 will make. At the end of the 64th revolution, the crew will burn the Service Propulsion System engine for 2 minutes and 42 seconds to start them on their way back to Earth for a 65 hour, 29 minute flight return to Earth. During this revolution while on the frontside of the Moon in radio contact, we'll be passing up the final set of numbers that the crew will put into their onboard computer for the spacecraft's Service Propulsion System burn. And we'll be getting final looks at all of the CSM systems prior to committing to Trans-Earth Injection.

This is Apollo Control at 199 hours, 11 minutes. That was Astronaut Stuart Roosa who has been running a number of simulations in the simulators here at the Manned Spacecraft Center reproducing the problem that has existed in the thrust vector control in the Apollo 16 backup guidance system. He was going through with Ken Mattingly what the crew on Apollo 16 -

This is Apollo Control. Our spacecraft communicator for the Trans-Earth Injection maneuver will be astronaut Don Peterson. He is accompanied at the CapCom console by astronaut Stu Roosa, who a few moments ago was discussing with Ken Mattingly from his experience in the simulators what Mattingly and the crew of Apollo 16 should experience. If for some reason they had to switch over to the backup guidance system to control this Trans-Earth Injection maneuver, with the problem that they have had with the thrust vector control, how that system would control, and what they should expect to see and feel. In essence, Roosa's comments, from operating with a similar system in the simulator, were that the backup system should control very well. But there will be some oscillations due to the oscillation in one of the two axis of control of the thrust vector control system which transmits the commands to the SPS engine bell that gimbal it from side to side and up and down. In the yaw direction there are some oscillations in the backup control mode. However, Roosa found that with a precise sort of a set up that the Apollo 16 spacecraft has, and what he described as some sideloads that are characteristic of the way this engine is burning. It will damp out most of the oscillation shortly after the engine ignites, and would control properly, and would control the burn very well. This again, we'd reiterate, is a backup control system from everything that we've seen on the primary control system is expected to function normally and give the same excellent account of itself that it has in previous burns. The advice to Ken Mattingly, in the event that there is some unforeseen problem with the primary control system, is that he would go on around, not perform the burn, let us take a look at the primary system back on the frontside of the Moon. See if there would be any way of restoring that, and if not, the burn would be performed with the backup system which we would also expect to do a very good job of controlling the maneuver.

This is Apollo Control. Those were the final set of numbers that the crew will use for the Trans-Earth Injection maneuver. And they were virtually unchanged from the preliminary which were read up on the previous revolution, the time of ignition remains the same 200:33 21 seconds, the total velocity change 3,370.9 feet per second and the burn duration is unchanged 2 minutes 42 seconds, and the time of re-entering the Earth's atmosphere also unchanged, [at] 265:49:12 seconds. We have about 45 minutes remaining before we lose radio contact with Apollo 16, on this revolution. When next we reacquire radio contact with the spacecraft they'll be at the start of their 65th revolution and should be on their way back to Earth.

Apollo 16 at the present time is passing over the Descartes landing site for the final time on this mission. We have about 38 minutes now until we lose radio contact on this revolution.

That was Ken Mattingly reporting that the sub-satellite was launched from its position in the Scientific Instrument Module bay of Apollo 16 on time. The connection between the Lunar Module batteries and our ability to turn on the sub-satellite [to] begin receiving data from it is that the Lunar Module and the sub-satellite operate on the same frequency. The Lunar Module, of course, is no longer - we're no longer able to command it. It will not be impacted into the lunar surface; however, its communication system is still functioning and it is still putting out radio frequency energy - still transmitting and for that reason we're not able to activate the sub-satellite begin receiving data from it. This will continue until the Lunar Module batteries go dead.

This is Apollo Control. A few moments ago Ken Mattingly reported the spacecraft was beginning to maneuver to the proper attitude for the Trans-Earth Injection burn. We expect when they do that we'll momentarily lose lock on with the High Gain Antenna. In fact, we are hearing a bit of increase in the noise level now and we just had break in the lock. We'll be reacquiring [and] should have a good solid lock up again shortly. In the mean time we'll continue to have rather noisy communications between the ground and the spacecraft. And communications controller here INCO reports that we should be locking up shortly on an Omni antenna. And we've just done hat. We've got good solid lock on now. As an additional note of interest on the interference problem that we're having with the Lunar Module transmitter which is as we said on the same frequency as the sub-satellite. We're predicting that the LM batteries will die at about 211 hours ground elapsed time give or take an hour and a half. So at about 211 hours we should be able then to command the sub-satellite and to begin receiving data from it. Now there is a small possibility that we'll get a lock on the Lunar Module for a long enough period of time that we can command it to shift frequency so that we no longer have the interference problem. However, as soon as the LM breaks lock it will again revert to the original frequency so this would only be a temporary assist in the problem. And, until 211 hours plus or minus an hour and a half we don't expect to be getting any consistent data from the sub-satellite. We' re showing now 19 minutes, 25 seconds until we lose radio contact with Casper. As the spacecraft goes around the corner behind the Moon it should be in the proper attitude for the burn and flight controllers here will be getting a last look at all the systems and we'll be giving the Apollo 16 crew [the] Go for Trans-Earth Injection.

Ken Mattingly has reported a successful star check[. That] is an indication that the spacecraft is in the proper attitude for the Trans-Earth Injection burn. We're now 4 minutes, 22 seconds away from loss of radio contact with Apollo 16. When next we reacquire spacecraft and crew should be on route back to Earth. With a good TEI burn we would expect to reacquire Apollo 16 at 200 hours, 43 minutes [and] 10 seconds Ground Elapsed Time. If for some reason the burn is not performed on this revolution we would reacquire at 200 hours, 52 minutes [and] 50 seconds. The spacecraft weight prior to that 2 minutes, 42 second burn of the Service Propulsion System is predicted to be 38,232 pounds. Following the burn it will be 27,487 pounds. The difference of 10,845 pounds being in the propellant that'll be consumed in that 2 minute, 42 second burn. At the time of the Trans-Earth Injection maneuver the Lunar Module will be about 16 miles behind Casper - the Command and Service Module - and about one mile above. We're now three minutes away from loss of radio contact.

Apollo 16 [is] now behind the Moon out of radio contact [and] 26 minutes away from the 2 minutes, 42 second burn that will start them on their way back to Earth. About 45 seconds prior to loss of radio contact CapCom Don Peterson advised the crew that we were coming up on loss of con - loss of signal and said "see you on your way home", and we got a terse roger from John Young at that point. Again, those time of acquisition with a normal Trans-Earth Injection burn 200 hours, 43 minutes [and] 10 seconds, [and] without the burn 200 hours, 52 minutes [and] 50 seconds. And, when we reacquire Apollo 16 they should be moving rapidly away from the Lunar surface. From the Apollo 10 mission where we had television of that particular portion of the mission we recall [a] very spectacular view of the Lunar surface out the window of the spacecraft. The Moon dropping rapidly away and shrinking rapidly in size. At 200 hours, 8 minutes [and] 38 seconds this is Apollo Control, Houston.

This is Apollo Control. Now one minute, 30 seconds from reacquiring Apollo 16. Should the spacecraft for some reason not have burned it's Trans-Earth Injection maneuver we will be reacquiring in about 11 minutes. This burn with the Service Propulsion System engine was to be a 2 minute, 42 second burn producing a total change in velocity of some 3,371 feet per second, increasing the speed of Casper from 3,600 nautical - rather 3,600 statute miles an hour to about 5,900 statute miles per hour. In the course of this 2 minute, 42 second burn the Service Propulsion System engine would consume some 10,845 pounds of propellant. One of the things that's accomplished with the Trans-Earth Injection maneuver; and of course the prime objective, starting the spacecraft on its trajectory back to Earth. Well, also with this maneuver we set the splashdown time. From that point on there are minor corrections to the trajectory primarily to control the entry interface angle which is set at negative 6.51 degrees. Correction, negative 7.37 degrees. And with no problems of weather, and what we would have to change weather- Now we've just gotten the call of Acquisition of Signal right on time. We should be getting the first words from the crew. We're waiting for the antennas to lock up and communications are still quite noisy.

John Young, and Charlie Duke with the reactions very similar to what we've seen from previous crews as the spacecraft moves out very rapidly from the Lunar surface. We're sure that they are all eyes - every chance they get - looking out the windows and watching the Moon receding rapidly beneath them, growing rapidly smaller. The spacecraft velocity now is 7,957 feet per second.

That was John Young reporting [that] the burn was completely nominal.

Apollo 16 already 333 nautical miles above the Moon.

Apollo 16 now 583 nautical miles from the Moon and the velocity is dropping off down to 7,425 feet per second. John Young, so far, has been doing most of the talking reporting that Charlie Duke and Ken Mattingly were at the available windows taking pictures.

And Apollo 16 just passed through 700 nautical miles.

Apollo 16 is now some 1,400 nautical miles from the Moon.

And here in the Control Center, the Flight Dynamics Officer just confirmed John Young's reports from on board the spacecraft that that burn was almost precisely as planned. With a very small midcourse correction requirement showing at this time.

The ring that Charlie Duke was asking about is the glove lock ring. The problem that he described is in getting the gloves locked onto the suit and you heard him say that it does take some force to do it, but once they get it done, and get the gloves locked in place they're maintaining a good seal and the suit is passing suit integrity check alright. The recommendation, from Capcom Don Peterson, was that there is little we can do about cleaning the grit out of those wrist locks. They looked into the possibility of perhaps pouring water into them but they felt that that would only turn the dirt that's in there to mud and would really not improve the situation any. So the crew was advised to leave them as they are and apply the necessary force to get them locked. It appears that this will cause no problem. Apollo 16 at the moment is 1,766 nautical miles from the Moon continuing to climb out rapidly, although the velocity is dropping off, down now to 6,245 feet per second. And about 12 hours from now or at 212:53:36 seconds the spacecraft will again cross that mythical line we call the Lunar sphere of influence. At that point they will be under the dominant effect of Earth's gravity. We'll have our displays switched over from Moon reference to Earth reference and we'll begin seeing Apollo 16 accelerating toward Earth.

This is Apollo Control at 201 hours, 33 minutes [202:21]. Apollo 16 now 2,735 nautical miles from the Moon. The velocity [has fallen] to 5,782 feet per second and it's continuing to drop slowly.

This is Apollo Control at 202 hours, 14 minutes [202:02]. We're preparing to update the clocks in the Control Center and aboard Apollo 16. You heard Capcom Don Peterson a short while ago discuss this with the crew. And the clock update will amount to 24 minutes, 34 seconds - or 34 minutes - We'll try that again - 24 hours, 34 minutes, 12 seconds and at 202 hours, 30 minutes [202:18], or about 16 minutes from now that update will be entered into the clocks here in the Control Center and also into the clocks aboard the spacecraft. Faced with the problem with correcting flight plans all the way to - Here's a call from the crew - we'll pick that up.

This is Apollo Control. We have now completed the clock sync and update, synchronizing the clock aboard the spacecraft and the clocks here in Mission Control with an updated time, advancing them 24 hours, 34 minutes [and] 12 seconds. Faced with the choice of making the Flight Plan agree with reality would require updating events item by item to account for the difference in time introduced when the LM landing was delayed and the subsequent early departure for Earth, or making reality in effect agree with the Flight Plan we've chosen to do the later. Which means that we moved the clocks ahead 24 hours, 34 minutes and 12 seconds. And having completed that we're in effect back on the normal Flight Plan. At present time our clock reads 227 hours, 11 minutes 20 seconds . And at this point in the Flight Plan the crew will be preparing for their rest period. We've asked them to go back and pick up items about 30 minutes prior to that. Which includes putting the spacecraft in the Passive Thermal Control mode, rotating it about its longitudinal axis at the rate of 3 revolutions per hour to maintain the proper temperature equilibrium. Completing that they'll then begin their pre-sleep checklist and probably begin the rest period around 227:30 [202:44] although we expect that they will be a little late getting to this. And will begin the sleep period probably 30 to 45 minutes after that. That's somewhere around 228 to 228:30. In making this clock update it should now eliminate the need for most of the Flight Plan updates that we have been forced to make for the last several days. The clocks now agree with where we should be in the Flight Plan. An arbitrary change keeps all of the sequences as they should be and the intervals between the events where they should be. And we'll also have another clock with a nomenclature TV 5, which would be viewable on the - on the monitors in the news center, which is counting the actual ground elapsed time. Which is 202 hours, 17 minutes. But [the] time that is in sequence with the Flight Plan is the updated time, which now reads 227 hours 3 minutes. This time by the way, is arrived at by taking the Flight Plan time for Entry Interface and subtracting the predicted Entry Interface time, using the original or the older GET, the previous GET before we updated, then subtracting the Entry Interface time that we would have with our previous GET or Ground Elapsed Time, from the Entry Interface time that is showing on the Flight Plan. Now we come up with the difference in time, which is taken care of in the clock update of 24 hours, 34 minutes and 12 seconds. This then is the time that is used for the clock update. And as mentioned previously, we are now more or less back on the nominal Flight Plan. Now there would be several minor changes, but nothing like the number of changes that we have been experiencing for the last several days.

That was Charlie Duke giving us a visual description of the Moon from a distance of 7200 nautical miles. We are working on some Central Standard Time conversion figures which we'll pass along to you shortly. We'd like to get those checked and verified by the Flight Activities Officer. We hope that will assist in the process of converting the updated GET time to a Central Standard Time.

That was Charlie Duke telling us he'd like to send us some TV. Our network controller is - says we're working that right now. The primary problem, of course, is to get the necessary ground lines up -

And network says we just happen to have lines coming up for television that we were planning to receive from the Lunar Communications Relay Unit on the Moon's surface. So we hope that if we can get things in configuration, we'll attempt to get a television picture from the Command Module of the lunar surface.

This is Apollo Control. We're standing by now to receive television from the Command Module. Again to reiterate the situation as far as the TV goes. Charlie Duke reported being very impressed with the view of the lunar surface from an altitude of some 7,000 nautical miles, [and] requested that we get things set up on the ground to receive TV. Fortunately we were in fact set to do that but not from the Command Module. We were planning to turn on the camera aboard the [Lunar] Rover on the lunar surface at 11 pm Central Standard Time. Consequently, the lines between Goldstone, which is the Manned Space Flight Network station on which we were to receive the television from the Lunar surface - those lines were up and we were ready to go when we got the word from Charlie Duke that he was planning to turn on the television camera. So, we should be in good shape to receive a color picture from the Command Module of the Lunar surface. The plan as far as the television that we were going to get from the Rover is simply to delay that until the crew has completed the television transmission that their planning and then to pick up television from the Lunar surface. At the present time Apollo 16 is 7,697 nautical miles from the Moon travelling at a speed of 4,951 feet per second, and we're standing by for [a] television picture. Flight Director Pete Frank estimates that it would take the crew about five minutes to get the camera out and in operation.

This is Apollo Control. Our Network Controller reports that we're seeing sync and it looks like the camera is coming up. We don't yet have a picture, but we should have that shortly. And we've [now] got a black and white picture. That should be through the converter.

We suspect Charlie Duke is the camera operator, and that view a moment ago was John Young.

That view of the Moon came to us from about 8,400 nautical miles above the Lunar surface.

This is Apollo Control. That unscheduled TV transmission of the Moon and the interior of the Command Module lasted for about 15 minutes and it showed us the surface of the Moon from about 8,000 nautical miles. Now the crew will shortly be putting the spacecraft into the slow rotation and on its Passive Thermal Control or the Passive Thermal Control mode. And we hope before too much longer they'll be getting ready to begin their rest period.

This is Apollo Control. We're now getting ready to bring up the camera aboard the rover at Cayley Plain Descartes site. And expect to have the camera in operation for about 30 minutes. We have about 10 minutes acquisition time remaining with the 210 foot dish antenna at Goldstone, California. We'll then be handing over to one of the 85 foot antenna sites for the remainder of the 30 minutes that we expect to get television from the lunar surface.

The noise that we are getting on the downlink [from the] spacecraft is due to the handover from the 210 foot dish antenna at Goldstone to the 85 foot dish also at Goldstone. We've now gotten good lock-on and should have good solid communication.

This is Apollo Control. We're standing by now for the antennas at Goldstone, California which were locked-up on the Command Module.

As soon as the Goldstone antenna is properly pointed at the lunar surface we'll be switching over to the Lunar Communications Relay Unit camera.

This is Apollo Control. We're in the process of a shift handover in Mission Control at the present time. Flight Director Gerry Griffin and his team coming on now to replace the Pete Frank team and the spacecraft communicator on this shift, in fact already on duty is astronaut Tony England. We do have an updated time now for the EVA from the Command Module. That is scheduled to occur at the Flight Plan time of 242 hours, 55 minutes, that's our updated Ground Elapsed Time and that would be at 2 hours - rather 2:03 pm Central Standard Time tomorrow. That is the time - the predicted time for the hatch opening for the EVA, again that time is 2:03 pm central standard time. That's a change from the previous time that we had listed of 4:47 pm Central Standard Time. The Flight Plan time again, 242 hours, 55 minutes Ground Elapsed Time. In computing Central Standard Time, from our new updated GET, perhaps the easiest method is to - in the Flight Plan change the time notation at the top of each page which is the hour plus 54 minutes for example, the present GET time is 228 hours 43 minutes at the top of that page in the Flight Plan, which starts with 228, hours 00 minutes above that notation is the Central Standard Time notation of 23:54 or 11:54 [pm]. That time on the top of that particular page would then change to 11:08 [pm] or 23:08 Central Standard Time and that time would follow through the rest of the way through the Flight Plan. At the top of every page, that time updates one hour. The next page would go from 23:54 to 01:54, the way it is currently printed in the Flight Plan. To update that to the present Central Standard Time, it would simply be necessary to change it to 08, change the last two digits from 54 to 08. If a Flight Plan is not available, the total amount of time added to the clock since liftoff is 24 hours, 46 minutes. It would therefore be possible to get a corrected GET or in effect an actual Ground Elapsed Time rather than an updated Ground Elapsed Time by subtracting 24 hours, 46 minutes from the GET time that we're currently showing in Mission Control. In other words, we're not showing 228 hours, 44 minutes and 22 seconds. To get the actual Ground Elapsed Time, from that updated GET time, it would be necessary to subtract 24 hours, 46 minutes from that time. We do have a clock in the Control Center which is counting actual GET time and does reflect that difference of 24 hours and 46 minutes. On the TV monitors, that would be the clock with the nomenclature TB 5 and currently, that clock is showing 203 hours, 58 minutes, 53 seconds.

Tony England giving Apollo 16 a Go for spinup. That's the signal that they may begin the Passive Thermal Control mode, puting the spacecraft in a slow rotation of three revolutions per hour. Prior to the - following the PTC, after getting [the] spacecraft spun up, the crew will have completed all of the activities required before beginning their sleep period. At 228 hours 46 minutes [204:00] updated Ground Elapsed Time, this is Apollo Control Houston.

This is Apollo Control [at] 229 hours, 35 minutes [204:48] Ground Elapsed Time. Apollo 16 presently is 12,791 nautical miles out from the Moon approaching Earth at 4,700 feet per second. During the change of shift press conference just completed there have been no communications with Apollo 16. We'll continue to stay up live with the air/ground circuit until the final sign off. But it appears there will likely be a great deal of dead air.

This is Apollo Control at 230 hours, 7 minutes [205:20] Ground Elapsed Time. Apparently [the] Apollo 16 crew has indeed gone to sleep, without saying good night. Distance, 14,250 nautical miles out from the Moon, velocity 4,658 feet per second relative to the Moon. Spacecraft now weights 27,427 pounds. And at 230 hours, 8 minutes [205:21] Ground Elapsed Time; this is Apollo Control, out.

This is Apollo Control [at] 231 hours, 47 minutes [207:00] Ground Elapsed Time. Apollo 16 crew asleep at this time. No communications from them in over 2 hours - 2 and a half hours. Distance 18,747 nautical miles outbound from the Moon. Velocity 4,568 feet per second. For the statistical minded, here is some numbers on leaving the Moon's sphere of influence. The halfway mark in distance, the halfway mark in time. We exit the lunar sphere of influence in about 6 hours at a Ground Elapsed Time of 237 hours 27 minutes 51 seconds [212:41:49] and at which time the distance from the Moon will be 33,821 nautical miles. Height above the Earth at that time 187,827 nautical miles. The halfway point and distance will take place at Ground Elapsed [Time of] 266:39:00 [241:52:58]. The distance to both bodies, Earth and Moon at that time will be 112,726 [miles]. The halfway time in the Moon-Earth transit will take place at Ground Elapsed Time of 257:45:12 [232:59:10]. At the halfway point in time the distances are 87,593 [miles] from the Moon and 138,683 [miles] from the Earth. At 231:49 [207:02], this is Apollo Control.

This is Apollo Control [at] 232 hours, 47 minutes [208:00] Ground Elapsed Time. Some 3 hours, 12 minutes remaining in the Apollo 16 crew rest period. Crew apparently sound asleep at this time. Meanwhile the spacecraft is 21,445 nautical miles out from the Moon approaching Earth at 4,532 feet per second. And during this graveyard shift that's about all there is to say. At 232:47 [208:00], this is Apollo Control.

This is Apollo Control [at] 234 hours, 47 minutes [210:00] Ground Elapsed Time, One hour and 12 minutes remaining in the Apollo 16 crew rest period. However, they will likely sleep in another hour beyond this time. Apollo 16 presently is 26,754 nautical miles out from the Moon, approaching Earth at 4,484 feet per second. The Spaceflight Meteorology Group of the National Weather Service said this morning that weather conditions for the landing and recovery operations of Apollo 16 [on] Thursday are expected to be satisfactory. The planned landing area, near the equator some 1200 nautical miles south of Hawaii, has a weather forecast calling for scattered clouds, easterly trade winds at 10 knots, 3-foot seas, and a temperature near 82 degrees. At 234:48 [210:01], this is Apollo Control.

This is Apollo Control [at] 235 hours, 47 minutes [211:00] Ground Tlapsed Time. Although the wake clock shows 12 minutes remaining in the sleep period the crew actually will probably sleep an additional hour and half. No more than that unless they wake up and call the Control Center earlier than hour and half from now. Distance 29,421 nautical miles out from the Moon. Velocity 4,469 feet per second. Some of the major events coming up during the day would be the Mid-Course [Correction] 5 if it's actually performed. That still hasn't been pinned down yet why they're not [sic]. The velocity change is great enough to warrant doing it this time. The Trans-Earth EVA to retrieve the film cassettes from the Scientific Instrument Module, additional runs with some of the instrumentation in the SIM bay, Gamma Ray and X-Ray equipment. And that pretty well fills up the work dav with the next rest period scheduled to begin at about 252 hours 30 minutes [227:43]. At 235:49 [211:02], this is Apollo Control.