ALSEP Off-load

Drilling the Deep Core

 

Losing the Heat Flow Experiment

Corrected Transcript and Commentary Copyright © 1996 by Eric M. Jones.
All rights reserved.
Scan credits in the Image Library.
Video credits in the Video Library.
Except where noted, audio clips by Roland Speth.
Last revised 24 April 2017.

MP3 Audio Clip ( 12 min 43 sec )

[Charlie is deploying the Heat Flow Electronics (HFE) package 30 feet south of the Central Station as per LMP-14 and LMP-15. See Brian McInall's ALSEP Deployment Planimetric Map (10 Mb).]

[When the TV came on, the camera was pointed at the surface in a direction a bit north of up-Sun. Fendell raises his aim and begins to pan clockwise.]

[Fendell is panning along Stone Mountain.]

[I asked Charlie to point out the Cinco Craters that he and John will visit during EVA-2.]

[Duke - "They're about 3/4 of the way up on the right there."]

[Jones - "Below the break in slope. That's a good climb."]

[Charlie later pointed out that the location of the Cincos can also be seen in AS16-113- 18339, the first of the photos he took of John jumping at the flag. In that picture, the tips of the fingers of John's left hand delineate the upslope rim of the largest of the Cincos, Cinco A. They will do Station 4 just to the right of Cinco A.]

[Duke - "One thing, the picture that we took right after we landed as we looked out this left window (such as AS16-113- 18300) showed a lot more features than this. The higher the Sun got the more it washed out. So it's hard to pick out the craters at this Sun angle, which is now ten hours or so after we landed. When the Sun was low, there were a lot of features. You saw a lot of lineations and striations across Stone Mountain from bottom to top. Cinco Craters and the others were plainly visible when we landed. But, the higher the Sun got, the less you could make out these landmarks. And it really is important to have a low Sun angle, I think, to help you identify stuff. Especially for landing."]

["We learned that low-Sun angles give you the long shadows and definition of craters and stuff; it's really what your going to need, I think, for the long-duration missions where we stay up quite a while. When we start going out with the Sun higher in the sky, it's going to be difficult to navigate to specific craters. But, for specific landmarks like mountains and stuff like that, of course, you'll be able to do it. It's just amazing how the features seem to change with the angle of the Sun."]

120:56:35 England: Okay; we copy that.

[As indicated in the "EVA-I, III; 1 of 3" map, the larger of the Double Spot Craters is near BZ.6/80.7. John had planned to land at CA.0/81.0 and, as indicated in Figure 6-15 from the Preliminary Science Report, he actually landed near CB.1/80.6. See, also, a detail from Pan Camera frame AS16-4618. The ALSEP Central Station is near CA.7/80.2. They are about 220 meters north and slightly west of Double Spot.]

[When the white ejecta blanket surrounding South Ray Crater comes into view, Fendell stops his clockwise pan and reverses direction.]

120:57:00 Duke: John, we're not much off, I'll tell you.

120:57:04 Young: Yeah, I hope not, Charlie. (Pause)

120:57:13 England: (Passing on a question) John, did you happen to notice what heading you were driving on the way out to the ALSEP site?

[Fendell reaches the counter-clockwise stop. He may have been looking for the LM.]

120:57:36 Duke: (Grunting) Gummit. (Pause)

[This is Charlie's abbreviation of "Dadgummit". He is probably trying to release four Boyd bolts that secure the probe package to the Heat Flow Electronics package as per Item 2 on LMP-13.]

[Training photo 72-HC-137 shows John at another point in the ALSEP deployment and a labeled detail indicates the locations of four of the many Boyd bolts.]

[John's "nothing" sounds more like "Nah-thing" and causes some confusion in Houston. He is doing the steps under "Connect RTG" on CDR-17.]

[Training photo KSC-72P-111 shows John extracting the cable he will use to connect the RTG to the Central Station. Charlie is watching, probably to make sure he understands the procedure in case he has to make the connection during the mission.]

[Fendell starts a slow, clockwise pan with frequent pauses so the geologists in the Backroom in Houston can take Polaroid shots of their monitor.]

120:57:59 Duke: (Garbled) Boyd-bolt release. (Long Pause)

120:58:18 Duke: There we go. (Here) comes that beauty. (Pause)

120:58:35 Duke: Boy, I'll tell you, John, getting your alignments up here is gonna be something. (Pause)

120:58:48 Young: Okay. We'll work that problem, Charlie, when the time comes.

120:58:51 Duke: Okay, Tony, the old idiot-proof decal has made it...The probe is in the left hand, and the wires are not crossed.

120:59:05 England: Very good. (Pause)

[I have been unable to find, in the Lunar Surface Procedures volume, a decal that might have been on the probe package. It may have been added late in training after Charlie had trouble getting the probe wires crossed.]

[Fendell has the South Ray ejecta blanket in view.]

120:59:39 Duke: Tony, let me give you a question here. The down-Sun heat probe is gonna be within 2 meters of about a 5-meter (diameter) crater. Over. That's maybe a meter deep. Is that okay, or do you want me to move it?

[AS16-113- 18368 is a photo of the west probe and shows the 5-meter crater at the center of the frame. The object in the middle distance beyond and to the left of the crater is the jack with which Charlie will remove the deep core. The South Ray ejecta blanket is just below the distant hills. Kenesaw is the hill furthest left.]

121:00:03 Duke: Yes, I can; but it'll be more towards the portable (magnetometer)...(Correcting himself) I mean the LSM (Lunar Surface Magnetometer).

121:00:12 England: Okay, we'd like to do that.

[In Figure 3.4-3 from the Lunar Surface Procedures volume, the LSM is the three-armed instrument 35 feet northwest of the west (No. 1) heat flow probe. The Portable Magnetometer is a separate instrument that is mounted on the back of the Rover and will be used at several of the geology stops.]

[The crew is now in view. John is working at the Central Station, connecting the RTG cable as per CDR-18; and Charlie is closer to the Rover, working with the Heat Flow equipment. The large boulder north of the Central Station is beyond it to the right and Smoky Mountain is in the distance. Note that the Central Station is tipped up so that what will be the back-bottom edge is upright. This positioning allows John to connect the RTG cable without having to get close to the ground. AS16-113- 18371 shows the RTG and 18348 shows the Central Station in its final configuration. In the latter picture, the RTG cable is the thick, round one coming off the lower-left corner. Charlie moves east of the HFE package to position the up-Sun probe.]

121:00:22 England: Very good. (Pause)

[Charlie is sidestepping to his right as he lays out the cable for the up-Sun probe.]

121:00:34 Duke: Yeah, this is a super place right here for this up-Sun one. Okay, here we go with a big drill coming up!

[Fendell reaches the clockwise stop. The LM can be seen across the top of the console.]

[Off-camera, Charlie heads for the Rover to get the drill. His footprints to and from the Rover can be seen in AS16-113- 18365, 18366, 18367, and 18368. These photos also show the drill and the Heat Flow Electronics package]

121:00:54 Young: Yeah.

121:00:58 Duke: Boy, John, I'm gonna need about 23 gallons of water. This stuff sure tastes good. (Pause)

[Readers should note that John is unable to reach his drink valve and will go thirsty for the entire EVA.]

[Fendell pans counter-clockwise and finds Charlie at his seat, taking the seatbelt off the drill which rode out to the ALSEP site on the LMP seat.]

121:01:15 Duke: (Thinking about what he needs) Okay; drill.

121:01:18 Young: (I'll go) back over here and straighten out the line.

[Fendell pans counter-clockwise past John, who is walking over to the RTG. Fendell stops panning with the camera roughly centered on the boulder which is between the drill stem rack and the LSM on the right side of AS16-114- 18388. To the right of John in this picture we see the drill, the Heat Flow Electronics package, the RTG and, at the right edge of the picture, the Central Station. In the background, particularly on the right side of the picture, note the east-west ridge that forms the local horizon.]

121:01:25 Duke: Well, I almost tried...(Answering Tony) Oh, yeah, bearing to the LM is 033, the heading is 195.

121:01:36 England: Okay; 195.

121:01:41 Duke: Rog. (Long Pause)

[Fendell has pulled back on the zoom and moved his aim to the right. John is using a Universal Handling Tool (UHT) to straighten the RTG cable and is trying to get it to lay flat on the ground. Figure 35 in Judy Allton's Catalog of Apollo Lunar Surface Geological Sampling Tools and Containers shows a UHT with an Apollo 17 LRV sampler attached to the business end. Without the LRV sampler, the UHT is used to remove Boyd bolts and, when fitted into an adapter socket, can be used to carry equipment.]

121:01:57 Duke: What's that, John?

121:01:59 Young: That line between the - see it - the Central Station and the ALSEP (means the RTG) is gonna float in the air.

[Duke - "That was a premonition that things were really stiff."]

[Later in the ALSEP deployment, John will catch his foot under the cable connecting the HFE and the Central Station and will pull it loose.]

[John rests the UHT against the far side of the RTG.]

121:02:10 Young: Yeah. (Reading CDR-18) Okay, the collar is locked on the Central Station. I'm gonna get the subpallet, here. (Long Pause)

[Fendell zooms in on John who leans down, gets the UHT, and starts loosening the Boyd bolts that secure the Central Station antenna packages on the RTG pallet. In releasing a Boyd bolt, John only has to make about a quarter turn with the UHT. The Heat Flow Electronics package is in the foreground with a second UHT sticking up into the air. Charlie used that UHT to carry the Heat Flow package out from the Central Station.]

[John reaches down and takes two packages off the RTG pallet, heads toward the Central Station, but then stops to look at the base of the RTG pallet.]

121:03:24 England: Okay, we'll work that. (Pause) No, it doesn't have to be all white.

121:03:31 Young: Okay. That's my first question of the day. (Hearing Tony) Okay.

Video Clip ( 2 min 44 sec 0.7 Mb RealVideo or 25 Mb MPEG )

121:03:34 England: (And that's) our first answer.

[Charlie has backed into the field-of-view and we get an out-of-focus look at a recharge decal on the back of his PLSS.]

121:03:42 Duke: Tony, the drill tripod deployed just as advertised.

121:03:51 England: Very good. (Pause)

[Charlie has backed up a little farther and we see him separating the jack from the drill-stem rack.]

[Charlie sets the drill-stem rack on the ground next to the Rover, but it promptly falls over.]

[Charlie lays the jack on his seat and goes to his knees to retrieve the core caps. Although he is too close to the TV for us to see much of what he is doing, he is undoubtedly holding onto the Rover as kneels.]

[Charlie takes a few steps away from the Rover, bends his knees and bobs down to his left to retrieve the rack. The relatively large size of the rack undoubtedly made this grab relatively easy.]

[Charlie sets the rack down again. It starts to tip but he grabs it and, after a moment, gets it to stay upright.]

[Charlie turns to his left and starts away from the Rover toward the Heat Flow equipment. He has the core stem bag and the drill and grabs the rack as he goes by. He has left the jack on the seat. As he straightens up after grabbing the rack, he comes upon a football-sized rock, shifts his weight onto his left foot, raises his right foot, and hops past the rock. He then resumes his signature sideways hop.]

[This is the crater just beyond the drill in AS16-113- 18365. Note the depth of his footprints in the soft soil on the rim closest to the Rover.]

[Fendell follows Charlie.]

121:05:49 Duke: Boy, my suit feels good.

[Charlie goes down into another shallow crater and then out the far side. This is the crater on the left side of AS16-113- 18368. The 5-meter crater Charlie described earlier is at the center of the picture.]

121:06:00 Young: For what?

121:06:02 Duke: (Gesturing at the 5-meter crater) I'm gonna have to drill away from that crater. Tony, I'm about 4 or 5 meters away, is that okay? From that crater I described?

121:06:08 England: That sounds good.

[Charlie sets the rack down and then hops around to the east side of it.]

121:06:12 Duke: Okay, we'll start drilling right here, then. (Pause)

121:06:21 Young: Well, I don't think...That won't be any problem. The only thing goes down past there is the LSM.

121:06:28 Duke: That's what I thought.

[Charlie is holding the drill by a wire loop and puts the drill down so that he can remove the drill stems from the bag.]

121:07:05 England: Stand by a second, John. (Pause)

[Charlie is struggling to loosen the Velcro on the core stem bag.]

121:07:32 Young: Okay, (reading the bottom of CDR-18) "Level and align experiments package, by eyeball."

[Charlie gets the top of the bag off and flings it, with an underhand motion, off-camera to the left.]

[Charlie removes one drill stem from the bag and then lays the rest on the rack.]

121:07:51 Young: Right. (Long Pause)

[Charlie tries to thread the drill stem into the drill but without luck. The stems have a single thread which circles the stem in a rise of about a centimeter and, in shirtsleeves, it is trivial to get them threaded. Here, Charlie's finger motions are restricted by the bulky gloves and his arm motions are restricted by the pressure suit. All of the astronauts who tried this - Scott, Duke, and Cernan - had trouble.]

121:08:08 England: (To John) Okay, and we need about 30 feet between that heat flow hole and the LSM. (Pause)

121:08:26 Young: Understand. We'll give you that.

121:08:31 England: Very good. (Long Pause)

[On his fourth attempt to get the stem threaded, Charlie thinks he has succeeded and picks up the drill by the wire loop, only to have the stem detach. He puts the drill down again, moves around to the northeast of it - probably to get a better view - and finally gets the stem threaded. This first stem is 54 inches (137 cm) long.]

121:09:13 Duke: Whoo! Finally got it, Tony.

121:09:15 England: Very good. (Pause)

[Charlie picks up the drill by grabbing the stem just above the chuck, turns the assembly over and positions the bit in the ground next to the probe he laid down previously.]

[Charlie pushes the bit a few inches into the ground, removes a thermal cover from the drill and tosses it off-camera to our left.]

121:09:40 England: Outstanding. (Pause)

[Charlie gets about a foot of penetration; but, then, the rate slows dramatically. Something similar happened on Apollo 15 when the joint between the first and second drill stems went into the surface but, in that case, the cause was a faulty drill-stem design which prevented the cuttings from flowing upward past the joint. The drill stems were re-designed after Apollo 15. In Houston, someone comments, "Looks like he hit a rock".]

121:09:50 England: It slowed down.

121:09:51 Duke: It's not going in. Something hard in there. (Pause) Whatever it was, we got through it, Tony. It's speeding up again.

121:10:10 England: Okay, good show.

121:10:13 Duke: Right on down now. It's super now. It must have been a rock. I'm sure the regolith is covered with...(Pause)

[Charlie is speculating that, because the surface is littered with rocks, there are numerous subsurface rocks as well.]

[Charlie finishes the first stem.]

121:10:27 Duke: Okay, and first, the long stem is in.

[This first stem is about a meter long.]

[John is deploying the Passive Seismic Experiment as per CDR-19.]

[Charlie has propped the toes of his left boot on the drill stem, with his heel pressed in the ground, in an attempt to prevent the stem from turning when he tries to take the drill off.]

[Duke - "Sometimes the foot worked. In training, it would work real good."]

[Charlie goes to the rack to get the wrench, a tool that was added to the drilling kit as a result of the Apollo 15 experience. The wrench is slightly out of reach and, to get it, he picks up the rack, takes the wrench off, and resets the rack on the ground.]

121:10:58 England: Yeah, we were watching.

121:11:00 Duke: Gonna have to use the wrench.

121:11:01 England: Okay. (Long Pause)

[Charlie gets into position a meter or more from the drill, leans forward and puts his left hand on the drill to support himself while he reaches down with his right hand and engages the wrench on the drill stem. He then stands up, blocks the wrench with the outside of his left leg, and twists the drill off.]

121:11:32 Duke: That works like a champ.

121:11:34 England: Right. That new wrench is pretty slick.

121:11:39 Duke: Yeah, it is. (Pause)

[Charlie gets the drill off, grabs it by the wire loop and puts it down, well out of the way.]

Video Clip ( 1 min 12 sec 0.3 Mb RealVideo or 11 Mb MPEG )

121:11:53 Duke: (Don't) fall over, drill. (Pause)

[Charlie bobs down and tries a dynamic grab but he misses the wrench. The suit forces him upright. He moves around the drill-stem and bobs down into what might be described as a partial kneel and grabs the wrench successfully.]

[Jones - "The second time, you had your right leg well forward and the left leg was back - with the knee almost touching. It looked like you were fairly stable."]

[Duke - "Uh-huh. I was."]

[With the wrench in hand, he lets himself spring upright.]

121:12:11 Duke: (Garbled) How about that?

[Like the drill, the wrench has a wire-loop on the handle which Charlie now uses to hang the wrench on the rack.]

[There are ballet references in the Apollo 17 transcript starting at 144:56:23. Indeed, the crater at Apollo 17 Station 3 is now known as Ballet Crater.]

121:12:41 England: We sure agree.

[Charlie took a second, shorter drill-stem out of the bag and threaded it onto the one in the ground without any problem.]

[Charlie grabs the drill by the wire loop and attaches it to the top of the second drill stem.]

Video Clip ( 2 min 58 sec 0.8 Mb RealVideo or 26 Mb MPEG )

121:13:11 England: Mark (Marcus Langseth, the Heat Flow PI)'s pretty happy too.

[Duke - "Mark isn't going to be so happy in a little while."]

[Charlie has turned the drill a number of times to get it seated and, to stop the drill stem from turning with it, he grabs the stem with his right hand and turns it through three more complete revolutions. Once satisfied, he grabs the handles so that he can start drilling again.]

[Progress slows noticeably when the joint between the two stems goes into the ground.]

121:13:55 England: Okay, give it time to clean the flutes.

121:14:01 Duke: I'm not leaning on it. It may appear that I am leaning on it, Tony; but I guarantee you I am not.

121:14:08 England: Okay, we understand.

[It does look like Charlie is leaning on the drill. His feet are slightly back and his legs are straight. As the drill gets below waist, he bends his knees slightly so that he can keep his grip on the drill without putting more weight on it. After a few seconds, he splays his feet to the side to get lower still.]

[Charlie has finished the second stem. He jumps to his feet with ease and goes to the rack to get the wrench.]

[Charlie is probably referring to a crater just north of the spacecraft with blocky ejecta on the rim. He described the crater at 105:14:57, shortly after the landing. It is probably the crater above the thruster on the right side of AS16-113- 18307.]

[Charlie leans on the drill and attaches the wrench without difficulty. He then blocks it with his left leg and starts twisting the drill off. It takes quite a bit of force to get it to start turning.]

[It takes a bit less then two complete revolution of the drill before it comes off the stem. Charlie puts the drill off to the side and positions himself to get the wrench off.]

[Charlie jumps slightly, gets his left leg behind him, bends his right knee, and bobs down to get the wrench. Charlie's left knee doesn't get quite low enough to touch the ground and, at the lowest point, he grabs the wrench without difficulty and hops back up.]

121:15:18 England: Oh, beautiful! (Long Pause)

[Charlie stows the wrench on the rack, gets a third drill stem.]

[Charlie gets the third stem threaded without trouble. He seats it in the stem in the ground and them uses the tips of the fingers on both hands to do the threading. In the process, he is using small arm motions to do the threading and doesn't have to flex the glove.]

Video Clip ( 3 min 07 sec 0.8 Mb RealVideo or 28 Mb MPEG )

121:15:48 Duke: Hey, John, it looks great. How can you get that thing leveled out there? Amazing. (Long Pause)

[Off-camera, John is completing the steps under "Deploy PSE" on CDR-19. In his next transmission, he will "Report sun compass align". Figure 9-1 from the Apollo 16 Preliminary Science Report is a sketch showing the alignment mechanisms on the top of the instrument, the stool on which it sits, and the aluminized Mylar skirt that provides thermal protection. NASA photo KSC-71P-578 shows John spreading the thermal skirt around the flight instrument on 30 November 1971 during a final check before stowage. AS16-113- 18360 shows the deployed PSE with the LM in the background and 18347 is a closer shot with the Central Station in the background. In 18347, the object on top that looks like a cricket wicket is the combination gnomon and handle. The level bubble is in the white cup just to the left of the gnomon. The RTG is beyond the Central Station to the left and the upright object to the right of the Central Station is an anchoring post for the thumper-geophone line which runs west from the anchor. The cable running past the RTG is the LSM cable and the cable going off to the south is the Heat Flow cable which, by the time this picture was taken, had already been broken.]

[In Houston, EVA notes to Flight that they "sure don't know what the Commander's doing." As so often happens in such circumstances, the next transmission is from John.]

[Because Experiments was talking to Flight, no one in Houston is sure they heard what John said and they ask Tony to get confirmation.]

121:16:28 England: Okay, Charlie. Say that again, John. (Pause)

121:16:34 Young: 064-1/2. I pointed it at that thing that said "Sun", but that sure didn't do it. I guess you can handle that.

121:16:48 Duke: Tony, it bogs down as it goes down through rocks and things. Now it's getting really hard. It's giving me a lot of torque. Just...The third stem is just about in. (Pause)

[In Houston, they think John is talking about the PSE Sun compass but aren't sure. However, before Tony can ask, John's next transmission tells them where he is on CDR-19.]

[On camera, Charlie has nearly finished the third drill stem. He has his weight on his right leg, with the knee bent and his left leg out behind him. With his hands on the drill, he looks very stable.]

121:17:20 Duke: (Finishing the third stem) Mark. Okay, I'll call it quits on that one, Tony. (Pause as Charlie gets the wrench)

[In Houston, Experiments is telling Flight that they want the gnomon shadow on 090 on the Sun compass.]

121:17:35 England: (To Charlie) We copy that. (Pause)

[In Houston, Flight points out that John probably has the thermal skirt out and asks Experiments if they really want him to re-align the instrument. Re-alignment would require that John move the skirt and there would be a considerable risk of getting dirt on it. Under those circumstances, Experiments decides they don't want a re-alignment.]

[Young, from the 1972 Technical Debrief - "The PSE deployed normally. I had some misgivings about where we put it; but, we leveled it and deployed the thermal skirt. And we padded it (meaning the dirt under the stool) so that it would be level. The last picture I saw of it (see, for example, AS16-113- 18359) shows that it is up, off the ground, a little bit (where the cable emerges from under the skirt) and I don't know what to tell them (the PSE experimenters) about that because we sure made an effort to make sure it was flat. We did go back and check it three or four times during the mission, but it was up off the ground on one side. Maybe that will give them a thermal problem. With that rock between the PSE and the Central Station (see AS16-113- 18347), walking on one side or the other of that rock would tend to get a little dirt on the skirt. But it was level and they should be getting good data."]

[Charlie has attached the wrench to the drill stems and starts to twist the drill off. Fendell pulls back on the zoom and shifts his aim to the right so they can see John.]

121:17:52 Young: That's affirmative.

121:17:54 England: Okay.

121:17:56 Young: Can't you see it on the TV?

121:17:57 England: We're just now coming around there. Okay, that 064 will be fine, there.

121:18:02 Young: It (meaning the thermal skirt) ought to blind you (with reflected sunlight). (Long Pause)

[Fendell gets John centered and zooms in. John is standing next to the Central Station and has his back to us. He has just removed a dust cover from the thumper/geophone package and tosses the cover off to the north. We get to see the entire trajectory. Note that John has not yet raised the top of the Central Station. He will do that after he removes the mortar package and the Lunar Surface Magnetometer. The PSE is on the right side of the TV picture.]

[John steps over a cable and then backs away from the Central Station to the east, paying out the thumper/geophone cable.]

121:18:48 England: John, do you remember where the bubble was on the top of the PSE?

121:18:54 Young: In the middle (of course)!

121:18:56 England: Very good. I should have known.

121:19:02 Young: Gary (Latham, the PSE Principal Investigator) said we couldn't come back unless we put the bubble in the middle.

[Fendell zooms in on the Central Station, just as it rotates a few degrees counter clockwise because of unavoidable tension in the thumper/geophone cable.]

121:19:10 Duke: What's wrong.

121:19:11 Young: Charlie?

121:19:12 Duke: Huh?

121:19:14 Young: This thing pulled so hard that it pulled the Central Station.

121:19:17 Duke: Yeah. Can't you re-align it later?

121:19:20 Young: Yeah, that's a thought.

121:19:22 Duke: That was my problem with the RTG package, I...(Long Pause)

[The thumper/geophone cable has gotten fouled on the thumper assembly John is holding. The thumper assembly is shown in Figure 10-2 from the Preliminary Science Report and the conical housing on the bottom contains a cable reel. Just before his next transmission, John gets the cable cleared and resumes the deployment, angling to the north as he continues to back away from the Central Station. He reaches the mortar package subpallet - which Charlie had previously placed northeast of the Central Station as per LMP-13 - and rests the thumper assembly on it.]

[John heads for the Central Station, reading his checklist as he goes. He will get the mortar package off the top of the Central Station and, as per the last item on CDR-19, will take it NNE of the subpallet.]

[This is a training joke of some sort. There is only one rammer and Charlie is using it to emplace a heat flow probe in the first hole. Figure 9-1 from the Apollo 16 Preliminary Science Report shows the multi-element probe.]

121:20:41 Duke: And Tony, Mark (Langseth) has his first one - all the way in to the red mark (on the rammer) - on the Cayley Plain.

121:20:50 England: Outstanding! The first one in the highlands. (Pause)

[Dave Scott drilled two heat flow holes at Apollo 15 site, which was on the mare. Charlie also plans to drill two holes but, here, his "first one" refers to a thermal shield on the top of the deepest gauge. He is using marks on the rammer to judge emplacement depth.]

121:21:08 Young: Ask him what we're going to do if the temperature shows like it does at Hadley. (Pause)

[The heat flow readings at the Apollo 15 site were higher than expected and, consequently, the experimenters are very interested in the Apollo 16 results.]

121:21:37 England: Okay; Baker 7 and 8. (Pause)

[While Charlie was talking, John lifted the mortar package off the top of the Central Station. As he turns to his right and takes his first step toward the subpallet, we can see his trailing right foot catch a ribbon cable. The initial, telltale motion of the cable is subtle but, as he brings his left foot forward, we can clearly see the cable caught on his foot. As he goes between the Central Station, he lifts his right foot to clear another cable - as he had done previously - and, either because of tension on the cable draped on his left foot or because he catches his left toe on something, he stumbles slightly. Recovering from the stumble, he bends his right knee enough that his left knee almost touches the ground. He steps forward with his left foot and, again with his right, Fendell tilts the TV down slightly, perhaps having seen the cable caught on John's foot. As John makes a final step with his left, he appears to feel tension in the cable and, as he turns to his left to see what's happening, the cable pulls taut and tears loose from the base of the Central Station. John hops backwards away from the Central Station to get the cable off his boot and surveys the damage.]

121:21:46 Duke: What?

121:21:47 Young: Something happened here.

121:21:48 Duke: What happened?

121:21:49 Young: I don't know. (Brief Pause) Here's a line that pulled loose. (Pause)

[John puts the mortar package down and goes to his right knee to try to get the end of the heat flow cable. He rises without it.]

121:21:58 Young: What is that? What line is it?

[John kicks the end of the cable toward the rock and then gets down on his left knee, steadying himself with his left hand on the rock and his right leg out to the side. He picks up the severed end of the cable.]

121:22:05 Young: I don't know how it happened. (Pause)

[John rises easily, having moved his right foot slightly forward and inward, rocks his torso back far enough that he can push himself upward with his right legs and, then, merely has to step forward to get his feet under him. All of his movements are amazingly stable.]

121:22:12 Duke: Yeah.

121:22:14 Young: God almighty. (Pause)

121:22:17 Duke: Well, I'm wasting my time.

[John drops to his knees at the back of the Central Station, puts his left hand on a protruding piece of attachment hardware, and examines the connector. Photo AS16-113- 18348 is a close-up of the end of the cable and the connector.]

[John rotates back to get his center-of-gravity over his feet and rises easily, finishing off with a slight hop backwards to get his balance.]

121:22:36 Young: (lost under Tony) had our first catastrophe. It's broke right at the connector.

[John starts walking toward the mortar package; and Charlie comes into view, going to the Central Station to inspect the damage.]

121:22:45 England: Okay, we copy. (Pause)

[To get past the rock, John actually steps up on it and over. To my knowledge, this is the only record in Apollo of someone stepping up on something. The rock is approximately 20 centimeters tall and is equivalent to the rise of an ordinary household step.]

121:22:55 Duke: Yeah, I'll go do the (deep core). (Pause) Oh, rats!

121:23:02 Young: I'm sorry, Charlie. God Damn...

121:23:04 Duke: (Lost under John)

121:23:05 Young: ...I didn't even know it.

121:23:08 Duke: A bunch of spaghetti over there.

121:23:11 England: Boy, we can sure see that on TV. It looks like a mess. (Long Pause)

[Fendell follows John, who is backing away from the Central Station, paying out the mortar package cables. The two-meter boulder, that Charlie described at 120:40:46, is beyond John.]

121:23:34 England: I'm sure we're working it. (Pause)

[In Houston, Jim Lovell, the spokesman for the Science Support Room, tells Flight, "That might be a detachable connector. We're looking at it right now. We might want them to go back and look at it."]

121:23:47 England: We understand that the cable came off the connector, and we've got just the free end of the cable, is that right?

121:23:54 Duke: That's right. (Long Pause)

[John deploys the legs on the mortar package. This takes him quite a while but he gets them out eventually and places the package on the ground. Photos AS16-113- 18379 and 18380 show the mortar package in it's final configuration.]

[Young, from the 1972 Technical Debrief - "One of the legs on the mortar package hung up. I couldn't extend it. I can show whoever wants to know how that pin was hung up. If I had a pair of tweezers, I could have gotten in there and pulled the pin. But, with the pressure-suit glove, I couldn't get my fingers in there to do it. So, we deployed it in the ground with three legs extended."]

[John goes to the north side of the Central Station and, once there, uses the UHT to flip a cloth cover out of the way to the north. We get to see the entire flight.]

[Charlie and I stopped to discuss the loss of the heat flow experiment.]

[Duke - "This was probably the biggest strain that I think I had in the whole flight - when he pulled that loose. It was just a bitter pill to swallow, to have that happen."]

[Jones - "The first time I heard this, it seemed to me that the level of enthusiasm dropped precipitously for five or ten minutes."]

[Duke - "Oh, yeah; it did. It did until we got over this, 'cause it was a big loss. We'd worked hard on that. You know, we re-designed the whole experiment, really, as far as the drill goes and the tubes (meaning the drill stems) and the wrench and everything. So I really had to swallow hard."]

[Jones - "Do you remember anything about how you got yourself back on track?"]

[Duke - "No; we just got back to work. And I did the deep core, which helped. They said they'd work on it; and they said we might be able to fix it and don't worry now."]

[Jones - "It is a wonder that it didn't happen to somebody before this. Did you and John talk about this when you got back in, after you got off mike?"]

[Duke - "I don't remember. I think we probably bitched about it - the spaghetti and the memory of the things and that they won't lie flat. We'll have to wait to the debriefing to see if we talk about it."]

[Jones - "For somebody who wasn't involved, it just seemed like a heart-wrenching experience. And I, for one, admire the way the two of you were able to get it back together in just a few minutes and get on with it."]

[Duke - "Well, you've only got so much time on each EVA and you've got so much to do, you might as well fill it in with something instead of just standing around and feeling sorry for yourself. We got to work."]

[Young, from the 1972 Technical Debrief - "My feeling is: that kind thing is almost unavoidable. If the cables are way up off the ground, you never knew whether you were stepping on them or not. When you are standing in one-sixth gravity with a backpack (and RCU) on, you're looking about 3 to 4 inches in front of your toes - unless you make a positive effort to look over at them. Every one of those cables had a memory and were all at some distance off the surface. If you want to make that whole business compatible with the suit operation - when you run into the cable - it will be strong enough that it does something like pull the Central Station a little so that you know you're moving something. Maybe it should be such that it can stand a tangle and trip. That cable, evidently, was really flimsy. Some cables allowed you to do that. I was pulling the Active Seismic experiment around (at 121:19:02) and that cable was on there so taut that I actually moved the Central Station and had to go back and adjust it. I didn't pull the PSE cable; but I had the feeling that, if I had, it would have moved the Central Station. The LSM cable was very strong. But that (Heat Flow) cable wasn't. I didn't know I'd done it. And I certainly didn't mean to."]

[Slayton, from the 1972 Technical Debrief - "We should have helped you from the ground, some, on that. You can go back and look at the color TV and we could see it (especially the orange glint off the ribbon cable). The CapCom was looking at the black & white set and it isn't very obvious on black & white. Besides the time delay, we had the wrong flight display up."]

[I do not know exactly what Deke means by "we had the wrong flight display up", but it suggests that key people weren't looking at the TV picture.]

[Young, from the 1972 Technical Debrief - "It's an 8-second time delay for the whole thing to get through. You can probably do a lot of damage in 8 seconds."]

[The theoretical communications round-trip is about 2.67 seconds, but the color-wheel technology used to produce the color TV picture introduced an additional delay. However, according to Ed Fendell, the added delay was only about 0.5 seconds. John is probably overstating the delay, perhaps to make a point.]

[Journal Contributor Markus Mehring notes that John may be remembering the delay seen by the public TV audience and not the delay seen by people in the MOCR. "It seems as if the broadcast from the Westinghouse color camera in the CSM took roughly 10 seconds to be prepared to commercial TV-standards for public broadcast. This was not necessarily the case for the RCA camera system on the Rover, though, which basically was fully capable of sending in NTSC. What the public saw from the Rover camera merely had an extra 2-second delay (making a total delay of 2.67 seconds plus 2 seconds) because the signal went over a loop between two tape-recorders for synchronization purposes on the broadcasting side. Note that this applies to public broadcast only, while Houston had the direct signal, since they didn't need to cope with TV-standard limitations and thus could skip this signal conversion. Either the nearly 5-second delay for the Rover picture as seen by the public or the corresponding 10-second delay for the CSM picture could be the source of Young's '8-second delay'."]

[Slayton, from the 1972 Technical Debrief - "That's right. It probably would have been too late, anyway. But, it might not have been."]

[Young, from the 1972 Technical Debrief - "It was sure a tragedy. If it had just moved the Central Station before it broke. I would have stopped right there and fixed it."]

[Duke, from the 1972 Technical Debrief - "Every one of those cables had a memory. Every one of them were off the ground."]

[Young, from the 1972 Technical Debrief - "A guy really can't lift his feet too high around the Central Station because, when he does, he kicks dirt all over the PSE. It was a bad thing; but I still think it (the cable) was incompatible with the kind of limitations that we were working with in the pressure suit. I blew it. I tripped over the whole thing; but I didn't even know that I had done it. I was completely out as far as the Active Seismic Experiment (subpallet) when I looked around and saw this cable following me."]

[Duke, from the 1972 Technical Debrief - "It wasn't your fault."]

[Young, from the 1972 Technical Debrief - "It was my fault. I didn't know I did it."]

[Readers may also wish to examine an Apollo 15 video clip which shows Jim Irwin losing his balance at about 124:41:05 while he was attaching the SIDE cable to the Central Station. Dave had already attached the heat flow cable and it is easy to imagine that Jim narrowly avoided a loss.]