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I watched the fantastic movie "Apollo 13" recently and there was one scene that stood out as it looked like the crew was considering making a one way trip and landing on the moon.

The script goes like this:

NEWS ANCHOR (on TV) - The problem now is not there's so much question of adequate oxygen supply but it is the rate of consumption of water which is vitally needed for the cooling operations to maintain the electronic systems and so forth.

...

FRED HAISE - Gotta tell you, I had an itch to take this baby down though, and do some prospecting. Damn we were close.

JIM LOVELL - Gentlemen, what are your intentions?... I'd like to go home. We got a burn coming up. We're gonna need a contingency if we lose comm with Houston. Freddo, let's... let's get an idea where we stand on the consumables. Jack, get into the Odyssey and bag up all the water you can before it freezes in there... Let's go home.

Faced with little chance of returning to Earth, Fred Haise and Jim Lovell seem to be thinking about giving up on the return and focusing on setting foot on the moon. Was this the case?

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    $\begingroup$ This is actually a good question. If it was, it would probably be found in the book "Lost Moon: The Perilous Voyage of Apollo 13" by Jim Lovell and Jeffrey Kluger (sadly, id not not have a physical or electronic version I could search). Since its not on the Air-to-Ground transmissions, it won't be in any of those transcripts. I would not dismiss it completely, since Apollo 10 was not fully fueled exactly so that landing was impossible and no temptation was given. $\endgroup$
    – Polygnome
    Commented Feb 5, 2018 at 10:18
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    $\begingroup$ I've read lost moon some time ago @Polygnome, IIRC the conversation did take place but Lovell knew it was wishful thinking. He certainly didn't mention anyone discussing landing seriously. These were people with a very good sense of survival or they wouldn't have made good test pilots. $\endgroup$
    – GdD
    Commented Feb 5, 2018 at 13:44
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    $\begingroup$ "What are your intentions?" whether actually spoken by Lovell or not, is clearly a rhetorical question. $\endgroup$
    – Russell Borogove
    Commented Feb 6, 2018 at 2:18

2 Answers 2

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They weren't actually considering it. It's just one of those wishful thinking moments, or a joke to lighten things up. Furthermore, there isn't anything said along those lines in the official transcripts. The time it would have been said was around 3:05:00.

Also, they really couldn't have done so. They had already used fuel from the descent stage. The amount wasn't huge, but it was a 34 second burn. They also hadn't orbited, which would have consumed a fair bit more fuel. In all, they would have had to use more fuel then the descent stage had to allow it to land, not even counting the fuel they had expended. At best, they could have landed using the ascent stage, which wouldn't have been very likely, as it wasn't designed to be used in that way. And if they had landed, they would have had absolutely no chance of coming home.

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    $\begingroup$ The whole point of a one-way trip is not to come home so I don't know if the amount of fuel is relevant here. $\endgroup$
    – Edlothiad
    Commented Feb 5, 2018 at 11:54
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    $\begingroup$ @Edlothiad Would they have wanted to fatally crash into the moon or would they have wanted to land and walk around and then die from lack of supplies? Both of the current answers are saying that the former would be their only option. Fuel was needed to not fatally crash or fly off into space. $\endgroup$
    – Todd Wilcox
    Commented Feb 5, 2018 at 14:35
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    $\begingroup$ In addition to all the problems above, the LM wasn't built to take 3 people to the surface, even if they hadn't already used up some descent propellant. It would have meant leaving Swigert in the CM to freeze to death. I doubt that was a serious consideration. $\endgroup$
    – John Bode
    Commented Feb 5, 2018 at 15:09
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    $\begingroup$ A landing using the ascent stage was not possible, the landing gear was mounted to the descent stage. Without separation from the descent stage, the ascent stage engine could not be used. $\endgroup$
    – Uwe
    Commented Feb 5, 2018 at 15:10
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    $\begingroup$ They hadn't used a significant amount of descent-stage fuel at that point. They did a 30-second burn with the DPS about 5.5 hours after the accident, but it was at 40% power, yielding ~12m/s ∆v. However, the ~700 m/s ∆v required to enter lunar orbit from their flyby trajectory would have done so. $\endgroup$
    – Russell Borogove
    Commented Feb 5, 2018 at 16:19
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The stack of the SM (service module), CM (command module) and LM (lunar module) was on a free return trajectory to Earth. To get into an orbit around the Moon, the main engine of the SM was needed. But the SM was damaged by the explosion of the oxygen tank and no electric power was available in the SM. Some of the parts (tanks, valves, tubes, electric cables) needed for the main engine operation might been damaged.

So without electrical control, the SM engine could not be used for lunar orbit insertion. If they had used the descent stage engine of the LM for lunar orbit insertion, not enough fuel would have been left for a soft landing on the moon. The ascent stage could not be used for landing without separation of the descent stage with the landing gear mounted to it.

The radar used for landing measuring distance, height and speed of descent was mounted to the descent stage, without that the landing would be impossible.

For sources see Wikipedia.

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  • $\begingroup$ Can you add some sources? $\endgroup$
    – spacetyper
    Commented Feb 5, 2018 at 15:53
  • $\begingroup$ They did seriously consider restarting the SM engine though. From the actual photographs of the SM later, it would have started if the electrical power required to open the valves could be found. The tanks retained pressure and the bell was only scratched. The gimbals were damaged but lock gimbal should have worked. $\endgroup$
    – Joshua
    Commented Feb 5, 2018 at 21:18
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    $\begingroup$ On the other hand there was a nonzero chance the SM engine exploded due to piping damage from stuff we could not see. $\endgroup$
    – Joshua
    Commented Feb 5, 2018 at 21:24
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    $\begingroup$ I'm not sure it's as unreasonable as you make it out to be: the previous burn would have been <20m/s dV. Lunar insertion is ~700m/s dV. The descent stage was rated for 2.5km/s dV and a lunar landing is optimally 1.7km/s... IE, they were still within the realm of possible not using/scrubbing the ascent stage. If they planned ahead, jettisoning the ascent stage fuel before lunar orbital insertion would give them about 30% more dV, or 3.2km/s... which would give them an orbital insertion and landing with nearly normal dV margins (~800m/s extra) entirely on the descent stage... just a TWR bump. $\endgroup$
    – TemporalWolf
    Commented Feb 5, 2018 at 23:21
  • $\begingroup$ @TemporalWolf : I doubt that jettisoning the ascent stage fuel was possible without damaging the descent stage. The propellant was hypergolic, the components spontaneously ignite when they come into contact with each other. I don't think the LM had extra propellant dumping valves. $\endgroup$
    – Uwe
    Commented Feb 6, 2018 at 9:56

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