Apollo 14 Lunar Surface Journal Banner

Landing at Fra Mauro

Corrected Transcript and Commentary Copyright © 1995 by Eric M. Jones.
All rights reserved. MP3 audio clips by Thomas Schwagmeier.
Last revised 26 June 2015.

[There was a 40 minute 2 second launch delay from Earth because of weather. Times given in the first column are measured from the time of actual launch (Ground Elapsed Time or GET). Times given in the text refer to the planned launch time (Mission Elapsed Time or MET). On the way to the Moon, the Apollo 14 trajectory was changed slightly to get the crew to the Moon at the planned time.]

[Note that Apollo 14 was the first mission used the CSM engine to put the LM in the low-perigee, "descent" orbit. Using the CSM to lower the LM perigee to 50,000 feet conserved LM fuel.]

[After Al Shepard and Ed Mitchell undocked the Lunar Module and began preparations for the descent, Houston noticed that a single bit in the memory was incorrectly set. This bit indicated whether or not the "abort push button" was open or closed. Normally, the button was open because, with the button in the closed position, the computer would use the Descent Engine to put the LM back in orbit. The abort switch bit indicated that the switch was closed. Houston asked the crew to physically tap the panel around the abort button and the result was that the bit cleared. Later, however, the condition returned and, in order to prevent an occurrence of the problem at just the wrong time during the descent, Houston decided to devise a set of modified computer procedures that would bypass the faulty bit. (Post-mission analysis suggested that the abort switch problem was caused by a stray piece of solder in the switch.) The new procedures weren't quite ready by the time Al and Ed went behind the Moon for the last time prior to the scheduled descent and, consequently, once they reappeared, Ed would have to copy the procedures in just a few moments and then, during the first few seconds of the descent engine burn, enter the new steps into the computer in the proper sequence and at the right times. Fortunately, there were few of the astronauts who knew the LM systems as thoroughly as Ed did and he did an outstanding job. Ed's knowledge of the LM was appreciated by other crews and, for example, Apollo 15 Commander David Scott specifically requested that Ed serve as CapCom during the Apollo 15 LM descent and lift-off.]

[Journal Contributor Paul Fjeld has provided a discussion of the abort problem and details of the program changes that were read up for Ed to implement, starting at 108:02:45.]

[Mitchell - "We disabled that circuit so that the system would not recognize the single point of the abort button. So that circuit was bypassed. Now that did, eventually, cause the radar landing problem that you were talking about earlier. Those two went hand in hand. That was a side effect of bypassing the abort switch."]

[Mitchell - "After the abort switch problem occurred, and we went behind the Moon, Al and I got ahead on our checklist because we knew we were going to be short on time before we started the burn to go to the lunar surface. And we did shift some of my duties to him, because I was the one who had to re-program the computer when they radioed up the changes, particularly the...Let's see. We had to do changes in both the main computer and the abort system computer. And I was the guy that changed them. Al flew the spacecraft and I did the programming changes that could not be done from the ground. So we departed from normal procedures in this period and, basically, Al was getting the spacecraft ready for descent and I was getting the computers ready for the descent as well."]

[Before beginning our review of the descent, I asked Ed to talk about normal LM cockpit procedures.]

[Mitchell - "Al controlled the DSKY (Display and Keyboard Assembly) and the main computer. And I double-checked him. As long as he was doing the entry on the computer and flying and controlling the spacecraft, I was acting as co-pilot and checking every entry that he made and keeping him straight and honest on the checklist. And there were certain periods of time when I would take over the DSKY, but we both knew I was going to do that. I mean, I never handled the DSKY at a period when he was handling it; and if he was doing something else and I was handling it, he never interfered with that. So we never reached across each other to throw any switches or make any entries, in any ad-hoc sort of fashion. It's just good cockpit procedure."]

[Ed was on the backup crew for Apollo 10, the final dress rehearsal for the first landing. During that flight, Tom Stafford and Gene Cernan flew their LM down to 50,000 feet above the lunar surface and then rehearsed the return to orbit by jettisoning the descent stage and firing up the ascent engine for a rendezvous with John Young in the Command Module. Although the maneuver had been successfully practiced in Earth orbit by the Apollo 9 crew, staging did not go smoothly on Apollo 10. As they approached the critical moment, the setting of a switch called the AGS (Abort Guidance Computer) Mode Control had to be changed and, unfortunately, Cernan and Stafford had a communications breakdown. According to Cernan (pp. 216-217 in his book The Last Man on the Moon), when the moment came, he changed the switch position and then Stafford, unaware that Cernan had already changed the setting, switched it back. Neither of them realized what had happened and, at staging, the erroneous switch setting resulted in unplanned thruster firings that soon had the LM spinning wildly. It took several seconds for the astronauts to diagnose the problem and regain control. The lesson, of course, is that they should have paid more careful attention in training to the details of who was going to do what and when and to make sure that, when switches were thrown, both of them knew what was happening. As Mitchell says, this is good cockpit procedure and it seems likely that he and many others paid close attention to the Apollo 10 lesson.]

[Mitchell - "I was on the backup crew for 10. Also, I'd been on the support crew for 9. Fred Haise and I probably knew more about the lunar module than any two guys alive at that point, since we helped build it at Grumman/Bethpage (the facility at Bethpage, New York, where the LMs were designed and built). And had been through all the cycles with all the spacecraft - with all of the lunar modules. And, of course, Stu Roosa and I were originally on Apollo 13 with Gordon Cooper. Then, when Al Shepard replaced Gordon on that flight, we switched flights with Jim Lovell's crew."]

[Jones - "Lovell's crew had been backup for 11 and, in the normal rotation, they would have flown 14."]

[Mitchell - "They'd been backup for 11 and, when Shepard came on the crew, we switched 14 and 13. So, by the time it came around to Apollo 14, I'd had a lot of simulator time on the lunar module and Fred Haise and I helped build the darn thing. And I'd been through Apollo 13 prime crew training. So there weren't many people around who knew the lunar module better than I did. And, during the Apollo 13 experience, where Fred and Jim had to bring their lunar module back as a lifeboat, I spent the 5 days of that emergency in the lunar module simulator, creating the procedures they had to use. And radioing 'em up to them in space. So, at this point, I could personally fly the lunar module blindfolded. Al was a very quick learner and a hell of a pilot, but he still didn't know the lunar module like I did. So our cockpit procedures were such that, when things were on his side of the cockpit and he was handling it, I kept hands off. But we double-checked everything, all the way down the line. And he knew what I was doing and I knew what he was doing, and we just double-checked each other all the way."]

MP3 Audio Clip ( 16 min 45 sec )

107:58:37 Shepard: And Antares is standing by for a PDI Go (Long Pause)

[The Flight Director is Gerry Griffin. Pre-flight photo S71-16804 (scan by J.L. Pickering) shows Apollo 14 Flight Directors Pete Frank (left), Milt Windler, Griffin, and Glynn Lunney posing in the MOCR.]
107:58:51 Haise: And, Antares; Houston. You're Go for Fra Mauro.

107:58:57 Mitchell: Good show, Fredo. Thank you.

107:59:00 Shepard: Thank you. You troops do a nice job down there...

107:59:02 Mitchell: That was beautiful. (Pause)

[The crew is thanking the ground for the quick fix to the abort switch problem.]
107:59:11 Shepard: Okay, if you watch us reset, we'll flip the page.

107:59:15 Mitchell: Let's go.

107:59:16 Shepard: Okay. (Pause)

107:59:25 Mitchell: (Garbled).

107:59:27 Shepard: Okay. All procedures are normal from here on in except at 26 (seconds into the engine burn), I actuate the Manual Throttle to Full on my side.

107:59:34 Mitchell: That's correct. I'll start reentering the DPS (Descent Propulsion System, pronounced "dips") after you have throttled up.

107:59:39 Shepard: Okay.

[As indicated above, Ed will complete the steps of the procedure designed to circumvent the abort switch malfunction after Al does the manual throttle-up.]
107:59:42 Mitchell: Won't have guidance until after I give it to you, after the first entry. (Pause) Okay. We covered everything on that last one (that is, on the page in the checklist they've just discussed)?

107:59:55 Shepard: Yes, sir. (Pause)

108:00:00 Mitchell: At 10 feet per second, we (garbled).

108:00:08 Shepard: You're breaking up to me. Would you run your (microphone) sensitivity up full?

108:00:10 Mitchell: Okay. VOX sensitivity is full up.

108:00:13 Shepard: Okay. (Long Pause)

[They are wearing suits, helmets, and gloves, albeit unpressurized because of the near impossibility of flying the spacecraft with a stiff suit.]

[Mitchell - "We were wearing suits, absolutely, but did we have helmets and gloves on?"]

[Jones - "The reason I think you do is that when you get down - after T-2, I think - you take them off."]

[Mitchell - "That sounds right. I can't imagine us going down...God, 20 years is a long time! I can't imagine us going down without helmets or gloves on. So it must be the case."]

108:00:25 Shepard: All righty; it's a beautiful day to land at Fra Mauro. (Long Pause) Okay, we'll bring Master Arm on 30 seconds in case simulations hit us again.

108:00:50 Mitchell: Okay.

[Mitchell - "What he's referring to there is that if we were going to get a malfunction introduced in a mission simulation, it was normally at this time. And the actual mission was a lot simpler than the simulations because (in the simulations) they were always playing war games and failure-games and what-if games. And there was nearly always one that took place at that time. I can't remember the exact failure, but we had the procedure there as to the exact point that Master Arm switch came on. And I don't recall what failure would take place if you didn't do that one sequence."]

[Jones - "And the Master Arm switch basically enabled the descent engine to fire and also enabled the explosive bolts in case you wanted to abort the descent."]

[Mitchell - "Right. And, as I recall, the Master Arm had to be on before the Engine Arm had any effect. Now, Al tended, quite often, to make cryptic remarks about simulations - well, we all did - because we tended to think of this as just a giant simulation and we'd think: 'Are the guys who induce the failures getting ready to induce another failure at this point?' And we were trying to be a little lighthearted about the fact that the abort switch problem was really a disaster. I mean, it had us pretty ginchy and gun-shy. God only knows what could happen next. And we suspected, in the back of our minds but didn't know for sure, that when you re-write a system and re-engineer a system as we did to get around that abort switch, you could create side effects. And it turns out we created one: the landing radar. But you never know that in advance. You don't know until it hits you. So we were a little nervous about all of that."]

108:00:52 Shepard: Houston, the Master Arm is On, and the A and B Lights are On.

108:00:57 Haise: Roger, Antares. (Long Pause)

[The electrical system - with which they will fire explosive charges to open the fuel valves or, in the event of an aborted landing, would detonate the explosive bolts that hold the two LM stages together - actually consists of a pair of redundant circuits. The A and B lights indicate that both circuits are healthy.]
108:01:19 Shepard: Looks quiet; looks good. (Pause)

108:01:28 Mitchell: Mark; 1 minute.

108:01:31 Shepard: Okay. And the radar temperature's coming up. (Pause) Okay. (Pause)

[This remark indicates that the radar circuitry, especially the device that actually generated the radar pulses, required a finite warm-up time. There is a radar temperature gauge on the instrument panel.]
108:01:45 Mitchell: Put that to Off?

108:01:50 Shepard: (I) see it. (Changing the switch position) There you go.

108:01:51 Mitchell: (Garbled) it got bumped.

[Mitchell - "I don't know which one it was, but something got bumped to the wrong position."]

[Jones - "There were guards on the switches?"]

[Mitchell - "On the real critical switches."]

108:01:54 Shepard: Okay....

108:01:55 Mitchell: (Garbled)

108:01:55 Shepard: ...(the) DSKY's on time.

[The DSKY is the Display and Keyboard Assembly for the Primary Guidance and Navigation System or PGNS, pronounced "pings".]

[Jones - "DSKY's on time? What does that mean?"]

[Mitchell - "It's counting down to time. And we ran independent checks - stopwatch checks. I was timing and checking the DSKY against the Abort Guidance System (AGS) computer...I was continuously checking. So, essentially, when he's saying the DSKY's on time, it really means it compares with stopwatch time."]

[Jones - "The AGS computer was designed to give you an abort capability in the event of a failure of the PGNS."]

[Mitchell - "The AGS was operable at any time when you went into abort. It didn't do a darn thing for you going down. But, when you went into abort, it continuously computed the trajectory back to orbit. What was missing was that we had to do the separation and the pitchover manually...Well, AGS might have done the pitchover. But we had to do the separation and the initiation of abort. Instead of a single-point abort switch, we had to go through a number of steps to do that."]

[Jones - "Jack Schmitt and Gene Cernan both talk about working during training for Apollo 17 to get the AGS in a condition where they could have used it to land had the PGNS failed. Did any thinking like that go into the preparations for Apollo 14?"]

[Mitchell - "The only thing we would have used it for would have been to get the descent velocity...well, to get velocity on all axes. We could do that. As I remember, the AGS only had one readout - instead of three like the DSKY. So, to get velocities in different directions, I'd have to call up a different program. I was pretty slick on the AGS. So I could call up programs pretty fast. And the main thing you would be interested in - landing with AGS - would be your descent velocity, because the guy flying it could pick up your horizontal velocity. What you didn't have a good (visual) feel for was descent velocity. Yeah, we could do that. We did a lot of things like that, that I don't know had been done on previous missions. And we did them only because I was so darn familiar with the systems that I could play games with them, you know, like a computer hacker. Those things were never designed into it. But I could do things with the AGS and with the main guidance system that really weren't in there, that weren't even in the checklist. But, here, what I'm doing is a double check, a double backup by timing procedures. I generally had a stopwatch going, checking the DSKY and the AGS against each other and playing all sorts of games."]

108:01:58 Mitchell: Engine Arm to Descent.

108:02:00 Shepard: Average g is On. The Descent Engine is armed.

108:02:04 Haise: Roger, Antares.

108:02:05 Shepard: There's Altitude and Velocity light. R3 looks quiet. (Pause) Okay. We're waiting for Ullage, Auto Ullage. (Pause)

108:02:18 Shepard: Okay, R3 looks good.

108:02:21 Mitchell: Ullage.

108:02:22 Shepard: Auto Ullage.

[The propellant tanks contain a mixture of propellant and helium used to provide pressure. In the absence of any acceleration against the direction of motion, there is no way of ensuring that it is propellant that flows through the valves and not helium. Consequently, the computer fires the RCS thrusters against the direction of motion, creating a small amount of acceleration which separates the lower density helium from the propellant. "Ullage" is literally the unfilled portion of a cask but, here, is used to describe the process of forcing the heavy propellant "down" toward the valve and the light helium "up" away from it. In the event that the computer did not give ullage, Shepard was prepared to do a manual backup.]
108:02:26 LM Crew: Pro(ceed).
[They are telling the computer to initiate engine ignition.]
108:02:27 Shepard: 3, 2, 1, 0...

108:02:29 Mitchell: Ignition.

108:02:30 Shepard: And we have Auto Ignition.

108:02:32 Mitchell: Ignition looks good.

108:02:33 Haise: Roger, Antares.

108:02:35 Shepard: We have an Auto Ignition.

108:02:39 Mitchell: Okay. Engine Arm, Override...(correcting himself) Engine Command, Override.

108:02:41 Shepard: Okay. And the Master Arm is Off.

[Mitchell - "This may have been a change in the procedure because of the abort button. We did not want anything going through there that would cause us to separate and switch to an abort orbit. So the procedure at this point (was) that any thing having to do with abort was totally manual. We would have had to have turned on the Master Arm; we would have to pitchover manually, we would have to switch the guidance systems via command, we would have had to have separated by command. Instead of a single point abort - as we would have normally had - there were, I don't remember now, maybe half a dozen steps to perform an abort. And one of the safety measures was to keep a spurious signal of any sort from going through there. We turned the Master Arm off so we would not get the surprise of inadvertent separation."]

[Journal Contributor Paul Fjeld has provided a detailed discussion of the modified procedures they are about to implement.

108:02:43 Mitchell: All right. Standing by for 26 (seconds into the burn).

108:02:45 Shepard: Okay. (Pause) We'll take the Throttle up at 26. (Pause)

108:02:54 Mitchell: Throttle up.

[Journal Contributor Paul Fjeld notes that, as can be seen in Table 8-V in the Apollo 14 Mission Report ( 9Mb PDF ), Al achieved the manual throttle up at 27.28 second after ignition, only about 1 1/4 seconds late.]
108:02:56 Shepard: Okay. We're at full throttle, Houston.

108:02:58 Mitchell: Command is Down. Verb (garbled) 5...

108:03:01 Haise: Roger, Antares.

[Fjeld - "Ed is starting to punch the sequence Verb 25 Noun 7 Enter, 101 Enter, 200 Enter, 1 Enter. This sequence sets ZOOMFLAG to permit Guidance Steering."]

[Jones - "All this down to about 108:03:32 are the manual procedures?"]

[Mitchell - "We're making changes to compensate for the fact that we've disabled the automatic system and are doing a whole series of things in a manual fashion...Not really manual. I mean, the computer was still flying the spacecraft down. But, as I recall, it was a modified manual/automatic procedure in order to get the ullage and to get the thing ignited. And, as I recall the throttle was in full instead of in...I don't know whether, on the normal procedures, we backed up this descent engine or not. But, in this case, it's clear that Al went up to full throttle and then, when we changed the internal logic, that disabled whatever we were doing at that point and returned it to an automatic procedure within the DSKY system."]

[Jones - "Because the computer was not getting some signals that it normally would have gotten, to trigger certain programs."]

[Mitchell - "That's right. Either that or we modified the procedure for safety sake, to make sure it didn't get spurious commands at that point. There were a number of things to consider. The first thing to consider was : we wanted to make sure, at this point, that we had a smooth descent engine startup. The guidance system worked and did start us down on our trajectory. The second thing: we backed that up with whatever procedures were necessary. All with a mind that it could either not work or it could throttle up and take us off on a different trajectory. So we were trying to box it in, so that it wouldn't fail out on the bottom side and it wouldn't go crazy on the upper side. And these procedures had to do with that."]

108:03:03 Mitchell: ...Noun 7, Enter 101.

108:03:09 Shepard: 1.7.

108:03:12 Mitchell: 001, Enter. Should have guidance. And you have Command and Throttle.

[Fjeld - "ZOOMFLAG is set."]
108:03:19 Shepard: Okay. We have guidance.
[Mitchell - "I think that all of this is change procedure, instead of automatic. I think that the computer would not automatically start guidance until I gave it control. And I think that's what these two or three lines is all about here."]
108:03:23 Mitchell: All right. I'm Disabling (aborts). Verb 25 Noun 7 Enter, 105 Enter,...
[Fjeld - "Ed is punching the sequence for resetting LETABORT, disabling aborts."]
108:03:31 Haise: You're Go at one (minute) Antares.

108:03:32 Mitchell: 400, Enter; 0, Enter. Okay. Landing radar enable: Verb 21 Noun 7 Enter, 1010 Enter, 77, Enter. The landing radar is there. Al, you can reduce your Throttle to Minimum.

[Fjeld - "Ed has now restored P63 in MODEREG so the State Vector routine will use the correct weighting function to apply to the radar delta H. '77' is the number for P63 in MODEREG."]
108:03:56 Shepard: Okay. It's coming down.

108:03:57 Mitchell: You have Command and Thrust (garbled) (Pause) Okay, Houston. The procedure is complete.

108:04:04 Haise: Roger, Ed.

108:04:06 Shepard: And we're standing by for Noun 69. As appropriate.

[They are asking if Houston has an update on their targeting based on tracking data.]

[Mitchell - "Well, I'm pretty sure that the Noun 69 portion was a normal part of our procedures. (True) The onboard system did its thing and started us down toward the programmed landing site, but Houston had the ability, of course, with that highly sophisticated tracking system they had...They had the capability very quickly after we ignited to see whether we were on what they computed was the desired trajectory. And, as I recall, Noun 69 was a standard program update - if needed - to correct for the landing site."]

[And, obviously, it worked very well.]

108:04:15 Haise: And, Antares, Noun 69...

108:04:15 Shepard: (Garbled under Haise) back to normal now, huh?

108:04:16 Mitchell: (Garbled under Haise).

108:04:18 Haise: ...is plus (+) 02800.

108:04:30 Shepard: Plus...What is it?

108:04:31 Mitchell: 02 - no, (only) one zero - plus 02800.

[The original 1971 NASA transcription of Ed transmission (on page 376) is "02 - no, 10 - plus 028 00." While reviewing David Woods’ 2015 draft of his annotated version of the landing film, I was puzzled by the original transcription until I realized that, while Al was entering the new value of Noun 69, Ed was monitoring what was being entered. Evidently, Al started by entering +00, rather than +0. Ed immediately called Al's attention to the error by saying "(only) one zero" and then repeated the entire sequence, "+02800". David and I exchanged e-mail about the transmission. In particular, David described Ed's "no, one zero" as a 'mild admonishion' and added that the incident 'goes with the idea that Al leaned on Ed's immense knowledge and competence with the LM throughout their time with Antares.']
108:04:42 Shepard: Okay, Houston, how does that look? (Pause)
[Mitchell - "As I recall now, (with regard to) virtually all of the change procedures as a result of the abort switch problem, I did the work on that. Al followed the normal procedures on the checklist and I did virtually all of the change procedures. And the way he's entering this (Noun 69), I can tell from the tone of his voice, that's something he'd practiced doing. That was our agreed upon way of doing it. So that Noun 69 was a part of our normal procedures."]

[Jones - "And I take it that Houston has the ability to look at what the computer's got and, at 108:04:42 when he asks Houston, 'How does that look?', Al is asking them to take a look and confirm that he's entered the correct value."]

[Mitchell - "Oh, yeah. They could read our DSKY, just like we could. And, of course, the difference is a two-and-a half second delay time."]

108:04:48 Haise: Okay; go for Enter.

108:04:53 Shepard: Okay, it's in.

[Journal Contributor Paul Fjeld notes that the ability to update the LM targeting was added on Apollo 12. He writes, "NOUN 69 was a very dangerous number. Every two seconds, among many other things, each pass of the computer through Guidance would update the Landing Site position in the Platform Coordinate frame to account for the turning of the moon, and reconstruct the Guidance Coordinate frame. On every pass, the computer would also add the vector DLAND to the Landing Site Position and then set DLAND to zero. DLAND is NOUN 69 and the astronauts could completely mess things up (and even kill themselves) if they set it wrong. NOUN 69 was loaded into the computer before PDI as all zeros (all balls), and, a couple of minutes into the descent, Houston would give them a Z (downrange) value (only) of the NOUN 69 vector to add to the Landing Site Position. They would punch the number into the first register only and wait for Houston to tell them it was okay before they hit Enter. Modifying DLAND on a whim or without a confirmation from Houston of the number entered could be suicidal)."]
108:04:55 Mitchell: Okay. Give me a two-minute-30-second hack, Al.

108:04:58 Shepard: Okay; my mark.

108:05:00 Mitchell: 2:30. Okay, we're a little fast. (The horizontal velocity is) about 10 feet per second (too fast). Little slow on H-dot and a little low. PGNS and AGS, that was in 2 foot per second; it looks good, it looks good.

[H-dot is the rate of descent, the time derivative of altitude. Ed is comparing their velocities and altitude with a chart which he has in front of him showing the desired values at particular moments of the descent. They are a bit lower than planned and, to compensate, the computer is giving them a slightly lower than normal descent rate. Ed is also comparing the descent rate estimates being displayed by the two computer systems and is finding only a very small difference of 2 fps.]
108:05:19 Shepard: Okay, it's almost back on the track.

108:05:20 Mitchell: Yep. (Pause) I'll give it a 3-minute mark, again.

108:05:28 Shepard: (Garbled).

108:05:29 Haise: And, Antares; you're Go at 3.

108:05:31 Mitchell: Go at 3. Okay, V-sub-i (total velocity) is good.

108:05:36 Shepard: Okay; understand. Go at 3.

108:05:37 Mitchell: H-dot is low; H is a little low; PGNS and AGS (have) a foot per second difference.

108:05:46 Shepard: Okay. (Pause) A little higher than AGS at the moment. Okay, you want to get those ED Batts out of the way.

108:05:57 Mitchell: Yeah. I was going to wait just another 10 seconds here.

108:06:02 Shepard: I'll look at the throttle convergence.

108:06:04 Mitchell: Take a look at ED Batts.

[Ed is going to check the voltages on the batteries which would provide current to the Explosive Devices (ED's) with which they would jettison the Descent Stage in the event of an abort using the ascent engine for the return to lunar orbit.]

[Mitchell - "We had a problem with one of the batteries on the way out. They'd noticed that one of the LM batteries was running a volt and half low as I recall. (Actually, LM battery 5 was running at about 36.7 volts, compared with a normal value of 37.0) And that concerned everybody, but it did seem to stabilize. We were particularly sensitive to the descent batteries. And, even though this was a planned step in the checklist, we wanted to take a hard look at it."]

[David Woods has provided scans of pages 15 ( 1.0Mb ) and 16 ( 1.0Mb ) from the Apollo 15 Lunar Module Cue Cards, which cover various abort scenarios. On page 16, for a return to orbit using either the descent engine (lefthand column) or the ascent engine (righthand collumn), The Commander would check the position of the Guiance Switch and then push either the Abort button or Abort Stage button, respectively.]

108:06:11 Shepard: Okay, throttle's converging; looks nice.

108:06:14 Mitchell: Houston, my ED Batts are Go, all in the green.

108:06:17 Haise: Roger, Ed. (Pause)

108:06:24 Mitchell: Isn't it a smooth ride?

108:06:25 Shepard: Yeah, it's great.

[Fjeld - "On Apollo 11 and 12, the propellant tank slosh baffles were not very effective so that, at about half empty, the swirling fluids would torque the LM out of its deadband with enough force that the Autopilot would have to use jets to correct their attitude. The jerking around also caused their LPD grid to be essentially useless. For Apollo 14, better baffles were cleverly installed through a two-inch hole at the base of each welded tank, like a ship in a bottle. They worked beautifully!"]
108:06:26 Haise: Antares, you're Go at 4 (minutes).

108:06:28 Shepard: Guidance is good. (Responds to Haise) Rog.

108:06:33 Mitchell: Four (minutes). V-sub-i is good. H-dot still low. H is converging, (that is, the altitude is closer to the planned value at this point in the descent). PGNS and AGS are about 2 and a half foot (per second) apart. Good. Down to 32,000 (feet altitude). We should be getting landing radar in very soon. (Pause) They're good; they're Go. (Pause) Okay, I will give an update at 12,000. There's a little difference in them. (Pause)

[The PGNS and AGS computers are in close agreement, a fact that gives confidence in both the trajectory and in both computers.]

[Mitchell - "V-sub-i is total velocity. What does "i" stand for? Inertial velocity. That's a guess, but it makes sense. Yeah, that would be our velocity along the trajectory. It's the magnitude of the velocity vector relative to something. So, if it's inertial, it should be with regard to a lunar-centered system."]

108:07:15 Mitchell: Come on radar, (garbled) lock on. (Pause) (Insistent) Come on radar. (Garbled) thousand.
[The landing radar is not getting any returns from the surface. Unbeknownst to the crew, the radar is operating in a short-range mode instead of the long-range mode which it should be in at this point.]
108:07:34 Haise: Antares, Houston. You're Go at 5.

108:07:36 Mitchell: (Garbled) the radar in.

108:07:39 Shepard: (To Haise) Roger. (Long Pause)

108:08:02 Mitchell: 5:30 (into the burn). (Pause) We're on profile.

108:08:08 Haise: Okay, 6 plus 40...

108:08:09 Mitchell: (Garbled).

108:08:09 Haise: ...is throttle down, Antares.

108:08:15 Shepard: Roger.

108:08:16 Mitchell: Roger, Houston. We still have Altitude (and) Velocity lights.

108:08:19 Haise: Roger. (Pause)

[Jones - "Does the fact that the lights are still on indicate that you don't have radar data?"]

[Mitchell - "That's the problem we're approaching. The radar has not come in. Now, let's review this. When I say at 108:06:33 'We're down to 32,000' - that's 32 thousand feet altitude - and the radar was designed to come in at 30 thousand feet. I started looking at it at 40 thousand feet because some missions had had it come in at 40 thousand. But it should be in by 30 thousand. When it didn't come in by 30 thousand, we got alarmed. And at 20 thousand feet, that's when we were frantically trying to get it to come in because, at 10 thousand feet, there was automatic (meaning 'mandatory') abort without landing radar. As I recall, we got it in about 18 thousand feet by cycling the breaker. The DR (descent rate) profile was very, very close (to the planned profile). There was very little update as a result of the radar."]

[The descent rate profile is, in essence, a plot of the descent rate versus altitude.]

108:08:24 Shepard: I'll bet they know that.

108:08:26 Mitchell: What?

108:08:28 Shepard: I bet they know that. Stand by for six (minutes). Mark, six.

108:08:33 Mitchell: Six. V-sub-i is good; H-dot is low; H (altitude) is high, now. We're running high on H. PGNS and AGS are together.

Audio Clip ( 1 min 01 sec )

108:08:42 Haise: Antares, Houston. We'd like you to cycle the Landing Radar (circuit) breaker.

108:08:49 Mitchell: Cycle the Radar Landing breaker.

[Al pulls the breaker and then puts it back in.]
108:08:52 Shepard: Okay. Been cycled. (Pause)

108:09:04 Mitchell: (To the radar) Come on in! (Pause) Okay!

108:09:14 Shepard: Velocity light (is out). Verb 57 Enter. How's it look, Houston? (Pause)

[According the Apollo 14 Mission Report, page 14-37: "The scale switching (that was preventing lock-on) occurred at a slant range of 63,000 feet (corresponding to an altitude of about 36,500 feet) with a beam 4 velocity of 3000 ft/sec at an incidence angle of 35.4 degrees. Operating the landing radar under these conditions exceeds the maximum gain and the system will be sensitive to any received noise. A test was performed with a radar operating under the Apollo 14 conditions - two range-rate beams locked up and the range beam unlocked. By inserting low-level noise for a fraction of a second into the receiver, range-scale switching occurred."]

["On future spacecraft, a wiring modification will be made to enable holding the system in high scale while in antenna position 1. Low scale will only be enabled in position 2. Position 2 of the (radar) antenna is automatically selected by the computer at high gate - 7500 feet altitude. The manual selection of antenna positions 1 and 2 will also control high- scale and enable low-scale switching, respectively."

[Jones - "And then, having set up Verb 57, Houston's looking at the radar information, making sure it agrees with their tracking."]

[Mitchell - "They're checking the radar information to see if they like it. If we all agree at this point, then we tell the computer to accept the data."]

108:09:27 Mitchell: Can we Accept?

108:09:29 Haise: Okay. We'd like to Accept the radar.

108:09:33 Shepard: Okay. Pro(ceed). Converging. Pro.

108:09:39 Mitchell: Great. Whew; that was close.

[Shepard, from the February 17, 1971 Technical Debrief - "Everything looked normal up until we began to get concerned about why the landing radar wasn't getting a good data signal into the computer, because the light stayed on on the DSKY. I'm sure that was being discussed on the ground, as well as in the cockpit. The call (to cycle the landing radar circuit breaker) obviously was an excellent call and that saved the day. So we pressed on down after that. I can't say enough for the ground people on that particular call. The updates after we went to the Verb 57 converged immediately and made us feel pretty good. We watched them for a while, of course, but pressed ahead."]

[Journal Contributor Tom Neal calls our attention to the following from page 351 in Gene Kranz's Failure in Not an Option: "After the (post-flight) debriefing, Shepard took (Flight Director Gerry) Griffin aside and confided, 'I had come too far to abandon the Moon. I would have continued the approach even without the radar.' On Apollo 14, the error in the LM computers' knowledge of the actual altitude was almost 4,000 feet before the landing radar data update. With an error this great in the computer, Griffin and the trench were convinced Shepard would have run out of fuel before landing. But everyone who knew Al never doubted he would have given it a shot. We also never doubted he would have had to abort. The fuel budget was just too tight."]

[In contrast, we learn from the Mission Report that, after the circuit breaker was cycled, "the initial slant range reading was approximately 13,000 feet greater than that calculated from the operational trajectory. Several seconds later, the indicated slant range jumped (down) from 32,000 feet to 25,000 feet (corresponding to altitudes of 18,500 feet and 14,500 feet, respectively). Subsequently, the landing radar readings compared favorably with the operational trajectory (fig. 14-22)."]

["The high slant range indicated at lock-on by the landing radar was most likely caused by the radar locking onto energy returned into the antenna side lobe. Based on the pre-flight terrain profile and the pre-fligh operational trajectory, side lobe lock-on can be expected. Checklist procedures exist to correct a sustained side lobe lock-on. Once the radar is locked on the main lobe (as seems to be indicated by the sudden drop in slant range from 32,000 feet to 25,000 feet as mentioned above), side lobe lock-on can not occur."]

[This discussion and, expecially, the figure, suggest that the PGNS and AGS altitude were very close to being correct and, indeed, once the radar had locked on with the main lobe and the data was accepted, the update involved a slant-range correction of less than 500 feet or so and an altitude correction of no more than 300 feet.]

108:09:40 Haise: Okay, and monitor...

108:09:41 Mitchell: (Garbled).

108:09:41 Haise: ...Descent Fuel 2.

[Jones - "The way I understand it is that there were two indicators of fuel in the descent, and they are telling you that they like the readings on gauge 2 better."]

[Mitchell - "They would take the lowest one. So the one that was shortest on fuel was the one you monitored."]

[Jones - "Unless it was nonsense."]

[Gerry Griffin, who was a Flight Director on several of the lunar missions, confirms that they chose the more conservative (lower) of the two propellant readings.]

108:09:45 Shepard: Okay, the throttle-down was on time, essentially. And we're on Descent Fuel 2.

108:09:53 Haise: Roger, Al.

[Fjeld - "Essentially is right. Throttle-down came 14 seconds early, about three seconds of that was due to the downrange site correction, but the rest of it was because Antares' engine performed better than predicted. The thrust of the DPS could be 50 or so lbs off the engine tag values that TRW (the maker) supplied the LGC programmers. The thrust also degraded as the chamber and throat protection ablated away and subtly changed the shape of the throat. The actual thrust was calculated with data from the three little accelerometers in the Inertial Measurement Unit and with an updated mass estimate. Apollo 14's engine thrust was 9862 lbs, 69 lbs greater than predicted, and this shortened the full-throttle burn time by 11 seconds."]
109:09:55 Mitchell: (Garbled). (Pause)
[Shepard, from the 1971 Technical Debrief - "Normally, after throttle-down, I had made a habit (in training) of switching to PGNS attitude hold to practice flying the error needles a little bit during that period. It helped to get a feel for how the vehicle was going to handle in that mode later on. We did not do that this time, because we were wrapped around the landing radar updating problem. However, I would still suggest it, I think. From my point of view, it gave me confidence being in the suited mode in the real world for the first time in the vehicle flying just about like it was supposed to."]
108:10:04 Haise: And, Antares; Houston. Your PGNS H-dot is the good one.

108:10:11 Mitchell: Okay, thank you. (Pause) Give you PGNS.

108:10:15 Shepard: (Garbled) leave that up?

108:10:23 Mitchell: (Static) 14,000.

108:10:26 Haise: Antares, Houston. You're Go at 8.

108:10:30 Mitchell: Roger. (Pause) Okay; AGS (garbled). (Static; garbled) looks good, Al. I'm starting the camera. (Pause) (Garbled)

[Mitchell - "That's the (16-mm movie) camera mounted in the right window, probably set on 6 frames a second or something. No, it's faster than that. Because, in the official photography...in fact, in the 'Trip to Fra Mauro' report, there's a part of that film in there and that shows Cone Crater going by. So it's on 24 frames per second."]

[The accompanying NASA photo, shows a portion of the plaster-of-paris landing site model used during training simulations. The area shown is centered on the landing target and shows Cone Crater at the lower right. My thanks to Journal Contributor David Harland who noticed that this is not a photo taken from lunar orbit. Compare with the corresponding mosaic of Lunar Orbiter strips.]

[Journal Contributor Gerald Megason has captured a sequence of four frames from the 16-mm film that show the approach to Cone Crater during the actual Apollo 14 landing. These are frames Cone-1, Cone-2, Cone-3, and Cone-4.]

DivX Film clip (6 min 05 sec) by Garry Neff
[A free download of the standard DivX player is available on the World Wide Web.]
108:11:04 Shepard: 10 seconds to go. (Pause) (Sixty) four. (Pause)

108:11:13 Mitchell: Okay, there's pitchover.

[Program 64 controls the "approach phase" of the landing and what happens first in P64 is that the LM pitches into a more upright position - from about 55 degrees off vertical to about 45 degrees, and then continues to pitch upright, but at a faster rate than was the case before P64. The sudden change in spacecraft attitude at pitchover gives Shepard his first look at the landing site.]
108:11:14 Shepard: 64 and we have pitchover, Houston.

108:11:15 Mitchell: There's PRO...

108:11:16 Haise: Roger, Al.

108:11:17 Shepard: There's Cone Crater.

108:11:19 Mitchell: And there it is.

108:11:20 Shepard: Right on the money!

108:11:21 Mitchell: That's it. Right on the money.

[Because of the distinctive landmarks available at this site, particularly Cone Crater which sits up on a ridge about 1.5 kilometers east and a little north of the planned landing site, Al has no difficulty figuring out where he is. Map "LSM Fra Mauro" shows Cone Crater filling the square at coordinates 90/DF. The planned landing site is at about 65/CQ, just west of the north-south string of three craters called Triplet which runs from 68/CL to 68/CQ. A pair of craters called Doublet is beyond the landing site at about 60/CS.]

[Shepard, from the 1971 Technical Debrief - "We came down to P64, pitchover, and there it was. The landing area model was excellent in that respect. It was an excellent training tool, and there was no problem in recognizing immediately where we were. I think that was probably obvious from the in-flight voice comments. There was no question about where we were. If we hadn't been there (that is, close to the planned trajectory), there might have been some question about where we were. But, fortunately, we didn't have to make that kind of in-flight test."]

[The landing area model - known as the L&A (Landing and Ascent) - was a model of the landing site which was hung from a ceiling in a training building so that a TV camera could be "flown" to and around it to give the crew in a LM simulator a feel for the view that they would have during the approach. Because there had been good pre-mission photo coverage of Fra Mauro, the Apollo 14 L&A was quite accurate.]

108:11:22 Shepard: What's the LPD (Landing Point Designator angle), babe?

108:11:23 Mitchell: LPD, 41.

[Shepard is looking through a set of scribe marks on his window and the LPD angle, which Ed will give him from the PGNS, will tell him where to look along the vertical scale to find the place where the computer thinks they are going to land. If Shepard doesn't like the spot, he can move his handcontroller to tell the computer that he wants to change the landing spot up or back or to either side. A single movement of the handcontroller forward or back, which moves the landing point by a half degree downrange/uprange, or to one side or the other, which moves the landing point by two degrees crossrange, is usually referred to by the astronauts as a "click".]

[Randy Attwood has provide a photo of the LPD scale in LM-9, the H-mission-capable vehicle scheduled for Apollo 15 before that flight became a J-mission.]

[Fjeld - "MIT referred to singe movements of the handcontroller as 'blips' and referred to the Rate of Descent switch toggling as 'clicks.' MIT also referred to the hand controller as an RHC - Rotational Hand Controller, same as in the Command Module, while Grumman insisted it was an ACA - Attitude Control Assembly - which they built unique to the LM)."]

[The flown handcontroller from Anteres is on display at the Astronaut Hall of Fame, Titusville, Florida. Photo and scan courtesy Ulrich Lotzmann.]

[Mitchell - "He's looking out a grid, here. A scribe mark on his window and, by looking at 41, he should be able to see - from his eye height - the landing site."]

[Jones - "Now, let's see. You were wearing restraint cords, that tied you down to the floor, but you could move front to back a little bit."]

[Mitchell - "Oh, yeah."]

[Jones - "I know that you could lean forward, because I know that several of the Commanders, prior to pitchover, would lean forward and try and sneak a peek. So, was it a matter in training and getting used to a certain position so that, when you looked through the window, you were looking at the right place."]

[Mitchell - "And, as I recall, it wasn't that sensitive. Because there were marks on the inside and the outside (that is, two sets of marks separated by the thickness of the window). If you moved your head right or left, backwards or forward, the inside and outside scribe marks wouldn't line up. You couldn't, just by changing position, mess it up."]

[Mitchell - "I haven't thought about the mission at this level of detail in a long time. But it is popping back in. It's just coming out like it's correct. It's like I've suddenly tapped into that portion of the memory bank. But I couldn't swear from a logical, memory point of view that what I'm saying is an accurate memory. But it sounds right; it feels right."]

108:11:25 Shepard: Okay. Fat. Fat as a goose.
[The audio at this point in the mission is difficult to understand and I was originally unable to pull anything useful out of the noise that covers Al's transmission. My thanks to Journal Contributor William Bianco who pointed out that Andrew Chaikin had successfully transcribed "Fat as a goose". After re-listening to the tape, I am comfortable with Chaikin's interpretation.]
108:11:29 Mitchell: 41.

108:11:30 Shepard: Beautiful!

108:11:32 Mitchell: Right out the window, just like it should to be. (Heavy static until 108:11:50)

108:11:34 Shepard: Outstanding!

108:11:35 Mitchell: Great.

108:11:37 Haise: Okay, Antares; Houston, here. Go for landing.

108:11:40 Mitchell: Okay. Here we go.

108:11:42 Shepard: (To Haise) Thank you, sir.

108:11:44 Mitchell: 3000 (feet altitude).

108:11:45 Shepard: (Garbled, possibly "Ground's next")

108:11:46 Mitchell: Okay, you're out at 3000, Al; 75 feet a second (descent rate).

108:11:50 Shepard: Okay, that LPD is (static clears) real good.

108:11:54 Mitchell: Houston, I'm on AFT (omni-directional antenna).

[Jones - "The 11 guys had a problem because the computer had a bad map of the LM for the high gain. Now, I seem to remember that you had had some problems with the high gain on the LM, and were anticipating using the Omni."]

[Mitchell - "Right. We thought we'd cleared up the high-gain problems for our mission, as I recall. But we were prepared for the high-gain antenna to give us trouble."]

108:11:56 Haise: Roger, Ed.

108:11:57 Mitchell: Okay, 2000; 48 feet (per second descent rate)...

108:11:59 Shepard: One click left.

108:12:01 Mitchell: ...coming down a little fast.

108:12:02 Shepard: One click left.

[Shepard, from the 1971 Technical Debrief - "One LPD (redesignation) was used - I think one left - to designate to the point that I'd originally thought was the right one, slightly south of track."]

[According to the Apollo 14 Mission Report, "a redesignation of the target point 350 feet to the south was made at an altitude of 2700 feet to allow a landing on what had appeared to be smoother terrain in the pre-flight studies of charts and maps. Several cross-references between the target and the landing point designator were made until an altitude of 2000 feet was reached, and good agreement was noted."]

108:12:03 Mitchell: 2000; 60 feet a second, a little bit fast, but not bad.

108:12:07 Shepard: Okay. (Pause) Outstanding!

108:12:11 Mitchell: Okay. 1500 (feet altitude). A little fast; not bad. Holding in well. LPD's 40, Al.

108:12:21 Shepard: Okay.

108:12:23 Mitchell: Coming through a 1000 feet; 27 feet (per second), right on schedule. Right on schedule, now.

[Among other things, Mitchell is consulting a descent profile chart which shows the desired descent rate as a function of altitude. According to the Pilot's Report section of the Apollo 14 Mission Report, "at some altitude less than 1500 feet, two things became apparent. First, that the redesignated (south) landing point was too rough and, second, that the automatic landing was to occur short (east) of the target."]

[Journal Contributor Frank O'Brien offered the following comment on the fact that "you want to target the landing site short - to get a good view of the surrounding area - and then head forward towards the real landing site. It turns out this was a major design criteria for the LM descent software. Pitchover was timed to give a minimum of landing site visibility - usually around 200 seconds. Given the angles of the LM during the descent, and the implications on visibility of the landing site, your options if you didn't like your landing site were that you went long or to the right or left. Landing short was possible, but not a great idea since it left you with very little time to size up the landing site. There is a paper with a great discussion of this in the Journal of Spacecraft and Rockets, written by Allan Klumpp, (who wrote P63 and P64 at MIT). It goes into the design issues, all the way to the guidance equations used for landing."]

[Paul Fjeld adds, "This paper by Klumpp is perhaps the best description of what is happening in the descent. There were several versions of it, the final one in "Automatica" Vol. 10, '74. Things were changed after the JS&R version (Vol. 5, No. 2 '68) so that the target was always at the desired Landing Site. Going short was okay, but it was best done early in P64 so you didn't have the target disappear below the window when the LM pitched back to put the brakes on. The technique in going right was to go past your target a couple of degrees so that you could trim up the crossrange corrections to the left, where the view was good."

108:12:32 Mitchell: Going by Cone Crater right outside to my right.
[Cone is about 1.5 kilometers east of the landing site.]

[Jones - "You seem to be glancing out the window more than the other LMPs. Or, at least commenting on things outside more often than anyone I can think of - with the possible exception of Charlie Duke on 16."]

[Mitchell - "I was a test pilot and my fundamental consideration was flying the machine. However, having been a pilot for many, many years, I've learned a scan pattern where I could hit the instruments, scan out, hit the instruments, scan out. But the primary task is to fly the machine. So my concentration was fundamentally on flying the machine. But I was stealing glances out the window with virtually every sweep. Although I wasn't getting to look out as much as I would like to, I took two looks at Cone Crater and I saw 'Yes, we're on course with respect to Cone Crater'. But my looking out the window was fundamentally a navigational thing, so I could back up Al's observation and help him identify where he was. Let's see; our landmarks were Cone Crater on the right, Doublet Crater and Triplet Crater (on the left). So, when I was looking out the window, it was a matter of backing up the navigation and advising Al, from my point of view, and it's the old...He's looking out the LPD and checking it. I'm looking out my window and checking it. And checking one against the other. So I was using it as part of my routine navigational backup to him, as well as monitoring the computer readouts on the descents."]

108:12:35 Shepard: Okay, the best spot is a little south of track, about halfway between Triplet and Doublet. Little south of track.

108:12:43 Mitchell: Okay.

108:12:44 Shepard: About 60 meters (south of track); that's where we're going.

[Shepard, from the 1971 Technical Debrief - "The LPD stayed good up until the point we got below 1000 feet. Then, it appeared as though it was going to be a little bit short, right about in the middle of Triplet."]

[Fjeld - "This was a classic problem with the LPD. The height is being updated by radar data, and when they are on an unmodelled slope, the target will tend to pull down or push up on the Index Line (window scribe marks). The technique is to overcorrect. Al redesignated once left for 350 feet, but then flew it out in P66."]

[On the various site maps, the planned landing point is at CQ/65 and they will actually land near CQ.3/65.8. South Triplet is the crater at CL/69 and North Triplet is at CP.5/68.5. The fresher of the two Doublet Craters is at CS/61.5.]

108:12:45 Mitchell: It looks good from here. (Pause) Looks good from here. Okay, Al; you're through 550 feet.

108:12:54 Shepard: Okay.

108:12:56 Mitchell: 16 feet per second (descent rate), 500 feet (altitude), 15 feet per second. It looks good. Your fuel is good at 10 percent (remaining). (Pause)

[At PDI they had about 18417 pounds of propellant and, at landing will have about 794 pounds remaining. Only Neil Armstrong landed with less fuel remaining, about 770 pounds.]

[Journal Contributor Paul Fjeld - "Up on the CDR's main panel beside the timers were two small digital EL (Electro-Luminescent) displays that showed fuel and oxidizer percent remaining. The crew could monitor either set of tanks by pushing the PRPLNT QTY MON switch to DES 1 or DES 2 depending on which was more conservative (Houston would make the call). The LMP would just look over and call out the lowest number."]

108:13:05 Shepard: Let's take it over and move up a little.
[Shepard has decided to take over manual control so that he can fly downrange.]
108:13:07 Mitchell: Okay. I think so; you're through 340 feet.

108:13:10 Shepard: Att(itude) Hold. (Pause)

[Shepard has now taken over manual control of the spacecraft and is using the handcontroller to fly the spacecraft like a helicopter.]

[Shepard, from the 1971 Technical Debrief - "It became obvious to me that I didn't want to land south of track because the (average) crater size (in that area) was a little too large, I thought. So, I flew her on over, using bank angle, (toward a point closer) to the nominal, original-intended landing point where it looked a little smoother. We used the same technique that we used in the LMS (Lunar Module Simulator). Ed was (reading instruments) in the cockpit, mostly, giving me values of velocities; and I was (looking at the scene) outside the cockpit, mostly."]

108:13:11 Mitchell: Okay. Okay; I'd give it a few clicks. You're through 200 feet, 5 feet...

108:13:19 Shepard: Go level.

108:13:19 Mitchell: ...per second. That looks good.

108:13:24 Shepard: Go level here.

[Al is killing his descent rate.]
108:13:26 Mitchell: Nine percent fuel, looks great. (Pause) Okay, you look like you're going right over the middle of Triplet. (Pause)
[Journal Contributor Gerald Megason has captured frames from the 16-mm movie which show the approach to Triplet. One of these, frame Triplet-1 shows North Triplet on the right and Center Triplet on the left.]
108:13:38 Mitchell: You're 170 feet, Al; 2 feet per second down; 8 percent fuel. You're looking good.

108:13:43 Shepard: Okay, babe.

108:13:44 Mitchell: 170 feet and holding (altitude). About 1 foot per second down. You want to speed it up a little bit.

[Ed is warning Shepard that he needs to start down so that they can land before the fuel supply reaches a critical level.]

[Jones - "Here is where he was hovering for a bit."]

[Mitchell - "It really wasn't quite hovering. He was simply holding that altitude. He'd brought it down and was continuing to slow down (along the trajectory) but he'd stopped the rate of descent. Before that, up at 108:13:11, it's 5 fps and he says 'level'. Okay. When you're down to one or two feet per second, you're flying pretty level. One or two feet per second isn't very much descent rate. And we were still moving forward. But, when I said 'you want to speed it up a little bit' he was slowing down, getting too close to a hover for the fuel that we had. And we needed to move on up a little bit (that is, descend more rapidly) and so that's when I urged him to get on up there. We were starting to get too slow."]

[From the time that Shepard takes over manual control through to touchdown, he flies the LM 1600 feet forward and about 1000 feet past the point at which they would have landed had he stayed on the unmodified decent trajectory. For comparison, Neil Armstrong flew the Apollo 11 LM about 1100 feet downrange from his target point because the computer was taking him into a boulder field surrounding a 100-meter-diameter crater.]

108:13:50 Shepard: Okay, I'm going to move forward a little.

108:13:52 Mitchell: Okay. (Pause)

108:14:01 Mitchell: Seven percent fuel. Okay, you're still at 170 feet indicated.

108:14:06 Shepard: Starting down.

108:14:08 Mitchell: Okay, you can move on forward. You're just barely crossing North Triplet. Barely crossing North Triplet. Six percent fuel; okay, 150 feet. There's (the) Descent Quantity light.

108:14:21 Shepard: Okay. (Pause)

[Mitchell - "I don't remember exactly what the Quantity Light meant (in terms of time remaining), but it meant you'd better get your ass down on the ground pretty quick."]

[The quantity light came on at 108:14:18, indicating 5.6 percent fuel remaining, enough for nearly two minutes of flight.]

[The Descent Quantity Light - labeled DES QTY - is one of a group of fourteen warning lights at the top of Panel 1, which is to the right of the CDR's window. All are Aircraft Red when illuminated. A similar group of caution lights are at the top of Panel 2. All are Aircraft Yellow when illuminated. Dave Scott writes, "Red was for 'emergencies'. We spent considerable time with the contractors defining the color, title, and placement of C&W lights"]

108:14:25 Haise: Low level.

108:14:27 Shepard: All right.

108:14:28 Mitchell: If you could land over here; there's some dust, Al; 110 feet. Three feet per second down. You're looking great.

108:14:34 Shepard: (Garbled).

108:14:35 Mitchell: Six percent; there's good dust. You're on your own. (Garbled).

108:14:41 Shepard: Starting down, starting down.

108:14:43 Mitchell: Okay. It says 90 feet, 4 feet per second; 5 feet per second, down.

108:14:49 Shepard: Okay.

108:14:50 Mitchell: Going down; looking great.

108:14:52 Haise: 60 seconds (of fuel remaining).

[Fjeld - "Haise, being the consumate LM Pilot himself, makes this call EXACTLY on time. 60 seconds to a BINGO fuel call, which means land in 20 seconds or abort immediately."]
108:14:53 Shepard: We're in good shape.

108:14:55 Mitchell: Okay. 50 feet down, 50 feet.

108:14:58 Shepard: We're in good shape, troops.

108:14:59 Mitchell: 3 feet per second (down), 40 feet (altitude); 3 feet per second, 30; 3 feet per second, looking great, 20 feet; 10, 3 feet per second.

108:15:11 Mitchell: Contact, Al.

[Note that the time indicated here - 108:15:11 - is the time since launch. The time given in the Apollo 14 Mission Report is only slightly different: 108:15:09 or 09:18:11 GMT/UTC on 5 February 1971.]
108:15:12 Shepard: (Garbled), Stop. Great, Pro, Auto, Auto.
[Fjeld - "Al left the engine on through contact and for about 1.7 seconds after touchdown, cooking the landing gear in the process."]
108:15:18 Mitchell: We're on the surface.

108:15:19 Shepard: Okay, we made a good landing.

108:15:23 Haise: Roger, Antares.

[Shepard, from the 1971 Technical Debrief - "The control of the vehicle, I thought, was good. Here again, of course, I did practice with the LLTV (Lunar Landing Training Vehicle), as well as the LLRV (Lunar Landing Research Vehicle), and in the LMS (Lunar Module Simulator). I felt completely comfortable and completely in control of the vehicle all the time."]

[The LLRV and LLTV were free flying vehicles equipped with jet engines that fired continuously toward the ground to remove 5/6th of the vehicle weight. A brief history of the LLRV has been produced by the Dryden Flight Research Center.]

[The Lunar Module Simulator was a stationary, shirtsleeve trainer, not unlike the flight simulators used in training airline pilots. It consisted of a cabin mock-up with a full suite of computer-linked instruments and controls and, in the windows, projected views of a lunar surface mock-up that changed as the pilot "flew" the simulator. During training, Al and backup Commander Gene Cernan each made 26 LLTV flights, the last on January 5, 1971, one month before the landing. NASA photo S70-56287 shows Al standing in front of an LLTV at Ellington Air Force Base prior to a 14 December 1970 flight.]

[Shepard, from the 1971 Technical Debrief - "I felt completely comfortable and completely in control of the vehicle all the time. The landing spot did turn out to be slightly on a slope. I don't think that was because of touchdown velocity, which must have been pretty low. We didn't have any stroking (that is, compression) of the landing gear at all. The LM ended up in about a 7-degree, right-wing-down attitude, which was exactly that of the slope in which we landed. In retrospect, maybe a little higher H-dot (descent rate or, literally, the time derivative {"dot"} of the height {"H"}) would have been better. We'd have ended with the vehicle at a more level attitude. But, in any event, with the combinations of slope (in the area), 7 degrees was not bad."]

["For touchdown, we had the habit of waiting (in training) about 2 seconds after the contact light came on before shutting the engine down. From the looks of things, we actually were on the ground and stopped before the engine shut off. It must have been a pretty light touchdown."]

[Mitchell, from the 1971 Technical Debrief - "From my point of view, after the last part of the descent, from the time the radar came in, things were fairly nominal. The AGS was updated on schedule. The (16-mm) camera was started on schedule and the checklist was followed completely the rest of the way down. It appeared to me that, when we pitched over, Cone Crater was right where it should have been. Al went ahead and made his redesignations. It appeared that the program was taking us to a point just short of North Triplet; at which point, Al took over and flew it on across North Triplet. From that point on, the landing was absolutely nominal, nothing different than we practiced in nominal Sims."]

[Shepard, from the 1971 Technical Debrief - "During the final approach, the visible landmarks were great. The zero-phase (the direction opposite the Sun, where shadows are largely invisible because they are hidden by the objects that cast them) was not a problem because we were approximately 14 degrees off the Sun angle. And at no time did I notice any problem at all with zero-phase during the final approach. The elevation and distance estimation of landmarks is always a problem as far as I am concerned. And the only thing I can recommend is that the CDR (Commander) carry in his head the geometry of the landing site, the size of the craters, and the difference between the crater landmarks that are used. He should know exactly what those distances and dimensions are ahead of time. That's one thing you've got to memorize because, as far as I'm concerned, at least, the L&A doesn't give you the feeling of...looking at a crater which is unfamiliar to you and saying that I'm 5000 feet above the ground or 2000 feet above the ground. It's just something that you can't do. You can't relate it to your Earth-bound experience."]

["I believe that we had less problem with dust than they've had before. I think it's because, as we comment later on, the surface of the general area in which we landed was less dusty - that is, exclusive of the dust around the rim of craters. The general area appeared to have less dust and we certainly had no problem with dust at touchdown. I referred to the cross pointers (velocity indicators) during the final stages of the descent at less than 100 feet, but only to assure myself that I had done the best I could as far as cross velocity (left or right) was concerned. The dust was obvious, but you could also see the rocks through the dust. We had no problems here. I think we had a touchdown that was very light, just a little plop when we hit the ground."]

[Mitchell, from the 1971 Technical Debrief - "That's what we had practiced because of the dust problems (experienced by the earlier crews, particularly Apollo 12). When we went into the ROD (Rate-of-Descent) mode, we leveled out on ROD and kept it flying on over until I was sure we were to Triplet and into that area where we wanted to land. Then we started down. I might add that, looking at the film of the descent last night, the dust problem appears a lot worse on the film than it appeared to me out the window. I thought I could see it (the ground) a lot better."]

[Shepard, from the 1971 Technical Debrief - "You probably would, in any event, because the camera is only looking at one spot and you don't have the more general feeling that your eyeball gives you."]

[Mitchell, from the 1971 Technical Debrief - "Right. But, just looking out the window, you can see the dust is no great problem at all."]

[Shepard, from the 1971 Technical Debrief - "Touchdown velocity was less than 3 ft/sec in all three axes, I would say. We were going slightly forward at approximately 2 ft/sec and 1 ft/sec to the right. The H-dot has got to be approximately 2 ft/sec."]

[Mitchell, from the 1971 Technical Debrief - "I don't think we were moving that fast forward."]

[Shepard, from the 1971 Technical Debrief - "It was pretty slow. That was one thing that I'd wanted to do as a result of using the L&A and also looking at the Apollo 12 touchdown (film). I think it's better to have a slight forward velocity because that way you're sure that, if you have just crossed over a crater, you're continuing to move away from it. You can only see about 60 degrees down by getting all the way up (that is, all the way forward) and looking at the (forward foot)pad, and that's not straight down. So, I had decided ahead of time that I was going to have a slight forward velocity just to assure myself that I wasn't backing it into something. I think that's the way to go. Certainly, a forward velocity of 1 or 2 ft/sec is well within the envelope, the other parameters being equal. It's my personal recommendation to make the landing that way."]

[During our 1991 mission review, I asked Ed about the preponderance of Navy people in the Commander's seat on the landing missions and if, in his mind, there was any particular reason for that fact.]

[Mitchell - "No, the makeup of the astronaut program - all over the program - was pretty well balanced. On Apollo 8, Frank Borman was Air Force, Jim Lovell was Navy, Bill Anders was Air Force. And then 10: Stafford was Air Force, Cernan was Navy (and on through the list)"]

[Jones - "The curiosity question was that the preponderance of the Commanders - the guys handling the stick - were Navy and Gene's thought was that perhaps it had something to do with carrier backgrounds."]

[Mitchell - "Well, it might have. But it really had more to do with getting in the pipeline. And, once you were in the pipeline, it had more to do with serendipity as to what happened. You went from backup crew to prime crew and you were programmed into the pipeline a couple of missions ahead; and who was available and who was doing what at that time...I don't think there was much politics in that or in programming of Navy or Air Force or whatever. On the other hand, there's not much question that the Navy guys with carrier experience had a little more fine motor skills - let's put it that way - with regard to the touchiness of some of these vehicles. We all had to transition and took helicopter training which peaked up the skill level. But all the guys were pretty qualified, pretty superb pilots. With very few exceptions. You were talking about the creme de la creme as far as pilots were concerned."]

[Jones - "So you're saying that it's a small set and just random chance could skew it."]

[Mitchell - "If you (were to) run across all of us, you'd find about as many Air Force as you do Navy. And its just kind of random chance as to what circumstances and what mission, etc. Once you were in that pipeline, then it's kind of like going down any pipeline and, wherever the holes occur, that's where you squirt out. That's the way it goes."]

[We then talked about assignments that people got when they first entered the Astronaut Corps.]

[Mitchell - "Our group had the opportunity, when we came in, of at least requesting our technical assignments. And I specifically requested the LM. And some of the guys specifically requested the Command Module as their area of expertise. And I felt that if I selected the Lunar Module, the chance of being a lunar surface participant was greatly enhanced by that. And, of course, it was. And, of our group, Fred and I...well I was the senior militarily in our group - and the oldest - and, as far as I know, there may have been some younger guys who had the qualifications - but, as far as I know, I was the only guy - up to that point and, perhaps, still am - that had both a doctor's degree in engineering and was a qualified, certified test pilot. I had pushed for those qualifications because I was going to go (to the Moon) one way or the other. And building up my qualifications level was the way I chose to do that. I just barely got into the program because of age. I was almost 36 when I was selected in and 36 was the cutoff, at least in my selection (group). But I had been pointing toward selection since about 1958. But, in 1958, I was too young and too junior and didn't have enough flight time. And they did learn, on some of the earlier selections that the younger fellows didn't perform as well. They didn't have the maturity and judgment. So, by the time I came along, you had to be between 32 and 36. And, building up my qualifications, getting my doctor's degree, and then I got shanghaied off to work in the military space program which I was a little frustrated about."]

[Jones - "Did you come out of MOL (Manned Orbiting Laboratory, a military version of Gemini which was canceled in 1969)?"]

[Mitchell - "Right. I was the Navy technical director for MOL. Now, I wasn't an MOL astronaut. After I finished my MIT doctorate, I requested assignment into the G&C (Guidance and Control) Division with Cliff Johnson. He was head of Guidance and Control at Houston when I finished my doctorate. And he was the first guy through the MIT doctoral program in Aeronautics and Astronautics. And I'd requested assignment to his division, while waiting for selection in the Astronaut Corps. I got shanghaied on the way from Boston to Houston. I was sent to the MOL program in Los Angeles as chief of the Navy MOL office. And I spent a year at that and then finagled my way out to Edwards to go through the Space School, and I taught the MOL astronauts out there in several subjects - in optimization theory and a few other things - and it was from Edwards that I got selected into the Astronaut program, just short of my 36th birthday. That was on my last go at it. You see, I'd applied at every opportunity from 1958 on. But my jet hours weren't enough, since I'd started out in props (that is, in propeller-driven aircraft). I started out flying in 1943, as a teenager. So I had a lot of prop time. But I didn't have enough jet time. So the combination of building up my jet hours - and, when you were on shore duty, it was tough to get jet time - and then getting my test pilot credentials. That's what pushed me over. But with normal Navy rotation, it took me until I was 36 to get all of that pulled together, even though I'd started in 1957. It took me damn near nine years to get all the qualifications pulled together that I wanted in order to be selected."]

[Ed was a member of the fifth group of astronauts. The group was selected in April 1966 and also included LMPs Fred Haise, Jim Irwin, and Charlie Duke.]

Journal Home Page Apollo 14 Journal Index Post-Landing Activities