Armstrong and Aldrin land on moon but never make it back to lunar orbit

acgoldis · Jul 26, 2009

Hi!

I saw an interesting tidbit of information on the Apollo 11 Wikipedia article:

"Years later, it was publicly revealed that Nixon had prepared a speech to be given if the mission resulted in death. The lunar module had not been tested to assess if it could launch from the moon surface".

Consider the following POD. Armstrong and Aldrin successfully land Eagle on the moon and perform their mission. However, there is a problem when they try to launch from the moon's surface to return to lunar orbit to dock with Collins. As a result, Armstrong and Aldrin are lost (as well as possibly Collins if the engine required to send the astronauts back to Earth was not part of Eagle).

I can envision two types of accidents (though I'm not an expert on this!). First, Eagle lands in terrain which causes it to be tilted away from the vertical as it settles. When the astronauts lift off, they wind up flying the wrong way and would need to make a course correction to get allow them to rendezvous with the orbiting module. Since Eagle was low on fuel by the time it landed, it does not have enough fuel to make a correction.

Another option is that the exhaust from the LEM's thruster reflects off the lunar surface (which Apollo 10 never had to deal with) and damages the ship somehow (though I can't think of a way this could cause a catastrophic failure).

At any rate, what would be the repercussions?

1. The disaster would have been seen all over the world -- after all, everyone was paying attention to this mission live (unlike the Apollo 13 incident, where people only started paying attention after the accident took place). The Russians would have probably had a field day and NASA would have a lot of egg on its face.
2. I can imagine Apollo 12 being delayed for a while so that the LEM could be tested. If NASA is smart, they'll scour the entire spacecraft, and in doing so find the problem which caused the Apollo 13 accident IOTL. I assume Kennedy wouldn't be stupid enough to try to launch Apollo 12 in 6 months to get a successful mission by the end of 1969.

Anything else?

Thanks in advance,
ACG

Dathi THorfinnsson · Jul 26, 2009

acgoldis said:
Hi!

I saw an interesting tidbit of information on the Apollo 11 Wikipedia article:

"Years later, it was publicly revealed that Nixon had prepared a speech to be given if the mission resulted in death. The lunar module had not been tested to assess if it could launch from the moon surface".

Consider the following POD. Armstrong and Aldrin successfully land Eagle on the moon and perform their mission. However, there is a problem when they try to launch from the moon's surface to return to lunar orbit to dock with Collins. As a result, Armstrong and Aldrin are lost (as well as possibly Collins if the engine required to send the astronauts back to Earth was not part of Eagle).

I can envision two types of accidents (though I'm not an expert on this!). First, Eagle lands in terrain which causes it to be tilted away from the vertical as it settles. When the astronauts lift off, they wind up flying the wrong way and would need to make a course correction to get allow them to rendezvous with the orbiting module. Since Eagle was low on fuel by the time it landed, it does not have enough fuel to make a correction.

Another option is that the exhaust from the LEM's thruster reflects off the lunar surface (which Apollo 10 never had to deal with) and damages the ship somehow (though I can't think of a way this could cause a catastrophic failure).

At any rate, what would be the repercussions?

1. The disaster would have been seen all over the world -- after all, everyone was paying attention to this mission live (unlike the Apollo 13 incident, where people only started paying attention after the accident took place). The Russians would have probably had a field day and NASA would have a lot of egg on its face.
2. I can imagine Apollo 12 being delayed for a while so that the LEM could be tested. If NASA is smart, they'll scour the entire spacecraft, and in doing so find the problem which caused the Apollo 13 accident IOTL. I assume Kennedy wouldn't be stupid enough to try to launch Apollo 12 in 6 months to get a successful mission by the end of 1969.

Anything else?

Thanks in advance,
ACG

While the LM being tilted or some crazy exhaust reflection problem arising is possible, I think the simplest POD is that some mechanism just didn't work. They cut the weight on the lander so much that everything was pared to the absolute minimum. A speck of dust in a switch, a mechanism that required earth gravity to work consistently (so it worked once in LEO with Apollo what, 10?).

It would have been really easy for the Eagle to have crashed (almost OTL) or not been able to take off.

Collins would have been fine.

To this day, no one knows why Apollo 13 happened, IIRC, so I don't think it would have been prevented.

e of pi · Jul 26, 2009

acgoldis said:
Hi!

I saw an interesting tidbit of information on the Apollo 11 Wikipedia article:

"Years later, it was publicly revealed that Nixon had prepared a speech to be given if the mission resulted in death.

I like this basic idea, it's one worth considering, but you have a couple pieces opf bad/mistaken data that I'll just go ahead and point out now so you can make your speculation properly.

The lunar module had not been tested to assess if it could launch from the moon surface".

Well, yes and no. The LEM had been extensively, even exhaustively tested as far as numerous test firings of both the decent engine (used for the landing) and the ascent engine used to launch the ascent section back into orbit. The only they hadn't done was actually fire one on the lunar surface, bu they'd done just about everything but.

Consider the following POD. Armstrong and Aldrin successfully land Eagle on the moon and perform their mission. However, there is a problem when they try to launch from the moon's surface to return to lunar orbit to dock with Collins. As a result, Armstrong and Aldrin are lost (as well as possibly Collins if the engine required to send the astronauts back to Earth was not part of Eagle).

This is possible. Collins would not be stranded, because the Eagle (the LEM, mind you) was not used to conduct the burn to return to Earth orbit; indeed, as soon as the LEM's job was done, it was discarded to save weight on that return burn. It's a slim possibility, but that's why Nixon had the speech readied. And Collins knew that there was a tiny chance he might be the only one to come back, he was trained to be able to fly back alone (as far as procedures, the psychological issues weren't anything he could train for in a simulator or anything).
[QUOTE} I can envision two types of accidents (though I'm not an expert on this!). First, Eagle lands in terrain which causes it to be tilted away from the vertical as it settles. When the astronauts lift off, they wind up flying the wrong way and would need to make a course correction to get allow them to rendezvous with the orbiting module. Since Eagle was low on fuel by the time it landed, it does not have enough fuel to make a correction.[/QUOTE]

As I noted, the LEM is really two spacecraft with two engines. One was the decent stage, which held the engine used for the landing and cargo space for equipment to be deployed on the moon, and the cockpit/ascent stage which would use the decent stage as a launch pad to return to orbit. The two stage's engines had separate fuel, and thus, the use of all but about 5 seconds of the supplies in the decent stage would not affect the ability of the completely separate ascent stage to return to orbit with fuel to spare.

Another option is that the exhaust from the LEM's thruster reflects off the lunar surface (which Apollo 10 never had to deal with) and damages the ship somehow (though I can't think of a way this could cause a catastrophic failure).

It really couldn't, not without a serious POD in the laws of physics or design of the LEM. The LEM's thrusters had good thrust, but astoundingly low pressure (the bells for extra-atmospheric rockets are bigger for the same thrust than atmospheric rockets, so have lower pressure--think of the same amount of water flowing through a bigger pipe).

At any rate, what would be the repercussions?

Ick, this is the tough bit where I have to stop nitpicking and put out my own ideas, isn't it? As you say, it would be catastrophic. Depending on what caused the accident, it may even kill the American lunar attempts, even if it's just public will (and thus money) that evaporates, not any technical reason. Mike Collins is the only survivor, returning to Earth as Buzz and Neil achieve another historic milestone of being the first men to die on another world. No matter how they go, whether by starvation or dehydration or lack of oxygen or something quicker to spare them a low death, they die, hundreds of miles from any other human, but with the whole world listening in. There would probably be a crash effort to try and diagnose/repair the issue, if a mechanical fault caused the landing to not work, but I doubt a fix could be devised that could be put into use on the moon with limited time and no spare parts. Space suits are the devil's own thing to do work in.

2. I can imagine Apollo 12 being delayed for a while so that the LEM could be tested. If NASA is smart, they'll scour the entire spacecraft, and in doing so find the problem which caused the Apollo 13 accident IOTL. I assume Kennedy wouldn't be stupid enough to try to launch Apollo 12 in 6 months to get a successful mission by the end of 1969.

No doubt that Apollo 12 is delayed, this would be an inquest on the scale of the investigation into the Apollo 1 fire, with all the implications in terms of public opinion and congressional support. It may evaporate completely, the entire program scrubbed from the budgets and seen as a death trap, even if that's not technically true. The cause of the Apollo 13 accident, unfortunately, cannot be found by looking in the LEM or even in the entire spacecraft, as it was an issue in the command/service module's oxygen tanks that resulted from an improper pad procedure, and was unique to that spacecraft anyway. Also, Kennedy wasn't President, Nixon was, though he might not be for much longer if he tries to speed up the review board to launch 12 on schedule.

[QUOTE} Thanks in advance,
ACG[/QUOTE]

Glad to help.

e of pi · Jul 26, 2009

Oh, god. This is what I was worried would happen. More corrections/thoughts:

Dathi THorfinnsson said:
While the LM being tilted or some crazy exhaust reflection problem arising is possible, I think the simplest POD is that some mechanism just didn't work. They cut the weight on the lander so much that everything was pared to the absolute minimum. A speck of dust in a switch, a mechanism that required earth gravity to work consistently (so it worked once in LEO with Apollo what, 10?).

Maybe. I doubt it though. The LEM was tested on Apollo 7, 9, and 10, with 10 performing a simulated landing that actually went within something like 10 miles of the surface. And the Grumman guys did their job well. Yes, they trimmed excess weight, but not down to the level you imply. The LEM was one of the most fault-free and well-built craft NASA has ever used.

It would have been really easy for the Eagle to have crashed (almost OTL) or not been able to take off.

The Eagle did not almost crash IOTL. There was an issue with the original landing site, but Neil took manual control to steer to a safe landing spot, and the craft itself was very stable in both landing and launch situations. There was a computer issue due to both landing and rendevious radars being switched on due to bad procedures, but the computer was designed to be able to shed unimportant processes and continued unimpeded by the excess of data. And as for not being able to take off...not easy, no. It used hyperglolic fuels, meaning that they would ignite when combined, no ignition required. All that had to work was for the valves to open, and that had been tested over and over and over. As noted, it was a very stable craft, and the guidance systems worked very well, so the launch back to LEO is also hard to screw up.

Collins would have been fine.

Yes. Well, physically. Mentally he's not gonna have an easy time.

[QUOTE}To this day, no one knows why Apollo 13 happened, IIRC, so I don't think it would have been prevented.[/QUOTE]

Wrong. We know exactly why. A pad error burned away insulation on the electric heating wires for the oxygen tanks, and this caused a spark which led to the tank igniting when the tanks were stirred to prevent layering of the oxygen. A simple check of wikipedia can tell you all the details far better than I can. But no, it wouldn't have been prevented as it was a one-time fault in pad technique.

acgoldis · Jul 26, 2009

I really hate to think what would have happened had the Apollo 13 design flaw not been discovered during the investigation into the Apollo 11 disaster. If OTL's Apollo 13 module's equipment is used for the ATL Apollo 12 mission and the accident occurs as IOTL, Apollo is in DEEP trouble. The first mission has three guys lost in a fire, the most famous one has two guys lost on the moon, and a year or so later there's the distinct possibility of three more casualties where only a miraculous recovery managed to get everyone back alive in OTL.

I really wonder if Apollo would have been cancelled and the Russians would have wound up achieving the first successful moon mission (1973 or so?), in which case they could have laughed at the Americans and gotten a lot of good propaganda out of it.

Scott_B · Jul 26, 2009

TV show the other night showed the thruster ignition switch broke off prior to taking off from the moon and they had to jam a pen into the whole as a makeshift switch.

POD: No pen on board, or no pen on board that fits.

Georgepatton · Jul 26, 2009

Dathi THorfinnsson said:
To this day, no one knows why Apollo 13 happened, IIRC, so I don't think it would have been prevented.

I was under the impression that they determined that one of the Liquid oxygen tanks had been overheated on the ground, stripping off the insulation on the electrical wiring inside. When they turned on the fans to stir the LOX, there was a spark and the thing exploded, leading to all the resultant unplesantness.

Dathi THorfinnsson · Jul 26, 2009

e of pi said:
The Eagle did not almost crash IOTL. There was an issue with the original landing site, but Neil took manual control to steer to a safe landing spot, and the craft itself was very stable in both landing and launch situations. There was a computer issue due to both landing and rendevious radars being switched on due to bad procedures, but the computer was designed to be able to shed unimportant processes and continued unimpeded by the excess of data.

No, it DID almost crash. They were within seconds of running out of fuel, through no fault of Armstrong or Grumman. The landing site was bad and they had to find something fast. It would have been easy for the nearest acceptable site to be just out of reach.

e of pi said:
Wrong. We know exactly why. A pad error burned away insulation on the electric heating wires for the oxygen tanks, and this caused a spark which led to the tank igniting when the tanks were stirred to prevent layering of the oxygen. A simple check of wikipedia can tell you all the details far better than I can. But no, it wouldn't have been prevented as it was a one-time fault in pad technique.

Oops. Mea culpa. I could have sworn they hadn't found a cause. So sure I hadn't bothered to look. My bad.

I will concede your points on the LM switches, etc. too.

I followed the Lunar program really closely when it happened - but I was 12 at the time, so apparently I didn't know as much as I thought I did.

Halcyon Dayz · Jul 26, 2009

Guess Leonov would be more famous now.

Scott_B said:
TV show the other night showed the thruster ignition switch broke off prior to taking off from the moon and they had to jam a pen into the whole as a makeshift switch.

For Want Of A Felt-tipped Pen.

Scott_B said:
POD: No pen on board, or no pen on board that fits.

I'm sure the switch board was serviceable.
And spaceships are designed with plenty of redundancies.

Dathi THorfinnsson said:
No, it DID almost crash. They were within seconds of running out of fuel, through no fault of Armstrong or Grumman. The landing site was bad and they had to find something fast. It would have been easy for the nearest acceptable site to be just out of reach.

If they had run out of fuel, they would have aborted.
Drop descent stage and fly the ascent stage back into orbit as practised on Apollo 10.

It really requires a fluke technical failure for Armstrong and Aldrin to get stuck on the Moon.
Something like a micro-meteorite causing a fuel leak.

Dathi THorfinnsson · Jul 26, 2009

Halcyon Dayz said:
If they had run out of fuel, they would have aborted.
Drop descent stage and fly the ascent stage back into orbit as practised on Apollo 10.

Hmmph!
I've read bucket loads of stuff on the Apollo 11 and those that mention the fuel problem never mention the planned abort. Nor do they mention Apollo 10, which I don't remember hearing of before, actually. 8, the around the moon flight, I knew. 9, the test LM in orbit, I knew. 10, I didn't. Sigh!

You know I HATE exposing my ignorance like this.

I suspect Apollo 10 is probably the most neglected Apollo flight ever.

Apologies for the dogmatic ignorance.