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Author
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Topic: Apollo 13 project: What would you have done?
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j0s9
Member Posts: 141
From: Clinton, MA, USA
Registered: Oct 2009
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posted 01-26-2010 10:56 PM
   
This is the topic for my Aero class project "Engineering Disasters: Apollo 13". Any answers, opinions and comments will be appreciated. Thanks for your time. - What would you do if you were in their shoes? (As an Apollo 13 astronaut and as an Apollo 13 ground mission controller, using both timelines and technologies 40 years ago and now.)
- What went wrong? using a personal non-technical view (very basic ideas/thoughts)
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Obviousman
Member Posts: 438
From: NSW, Australia
Registered: May 2005
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posted 01-27-2010 01:24 AM
Read Sy's book, and listen to the CD. That will give you a good grounding and show that they really did everything possible. Some very good decisions were made. With hindsight you could perhaps make some slightly different decisions, but if you were there in the hotseat... |
moorouge
Member Posts: 2458
From: U.K.
Registered: Jul 2009
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posted 01-27-2010 04:15 AM
The Apollo 13 accident is a very good example of how small events accumulate to make a big one. Very briefly the sequence leading to the explosion were these - - A jolt involving a movement of 2" whilst removing the shelf holding both oxygen tanks in the SM to be used on Apollo 10; this is thought to have displaced the filling tube in Tank 2. [It is alleged that a worker having removed two of the three bolts holding the shelf in place took a break. Coming back the crane was attached to lift out the shelf, but the third bolt, still in place, caused the shelf to slip from the crane. This is also perhaps an example of what can go wrong in mass production. Most pieces of a product are a mixture of bits which, though being within tolerances, are either slightly under or slightly over. Such a mixture makes for a reliable product. However, occasionally one gets something where all the under-sized or all the over-sized pieces come together. This results in a poor product.]
- Following installation of the shelf into SM109 (used on Apollo 13) some difficulty was experienced in emptying the tank of oxygen during pre-flight tests at KSC.
- To remove this oxygen it was decided to 'boil it off'. However, a switch voltage requirement change had not been made and, during this process, the same switches welded shut and the insulation was badly damaged.
- In flight, following a request to stir the tank, a short circuit caused an electric arc in the tank. This set fire to the damaged Teflon insulation.
- The increased pressure due to the fire leaked into the tank dome and, from here, burst violently through a relief valve set at 75 psi.
- Increased pressure in Bay 4 of the SM then blew off the panel, this hitting the antenna, etc..
- The rise in pressure/temperature in Tank 2 went unnoticed since the Master Alarm circuits were blocked by a routine caution from the fuel cell hydrogen tanks.
I hope this helps. It is worth remembering also that elements of the procedures used as the LM acted as a 'lifeboat' for Apollo 13 were developed and practiced on Apollo 9, particularly using the descent engine to return '13' to a free return trajectory.What would I have done? Bearing in mind the successful outcome it is hard to argue that those involved did anything other than the right thing, making the oorrect decisions at the correct time. |
garymilgrom
Member Posts: 1966
From: Atlanta, GA
Registered: Feb 2007
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posted 01-27-2010 06:58 AM
I agree with the above posters, the NASA team did almost everything right to save this mission. However there is one thing that could have been done earlier - tranferring the guidance platform from the CM to the LM. I think the ground was thinking "this must be an instrument problem" for quite a while before they realized the seriousness of the situation. Recognizing that earlier, or having a procedure where the platform is transferred immediately in any bad situation, might have eased some of the tension around that procedure. I understand there were many problems after this point, but they almost ran out of time transferring the guidance, and I'm not sure they could have recovered from that.Please note my thoughts are not intended as criticism of the great people involved at the time, we just have the luxury of speculating with 40 years of hindsight. I have the utmost respect and admiration for the Apollo 13 crew and controllers, this was truly one of NASA's finest hours. And I was spellbound talking to Fred Haise about the incident at an ASF event, these people, whether in the air or on the ground, are true heroes. |
moorouge
Member Posts: 2458
From: U.K.
Registered: Jul 2009
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posted 01-27-2010 10:23 AM
May I add one further comment to my previous posting.Hindsight is a wonderful thing and one should be wary of making decisions with a knowledge of events not known at the time events were unfolding. For this reason the question posed about what one would do now is an impossible one to answer. Yes - it would have been better if guidance had been tranfered to the LM earlier. At the time it was not at all clear whether the situation required this especially as first thoughts were that '13' had been struck by a meteorite. As it was, I believe that the suggestion that this should be done came originally from the crew and not from the ground. On second thoughts there is, perhaps, one thing I'd have done differently. Grumman issued a bill to North American Rockwell (builders of the CSM) for £173.000 to cover "towing your damaged vehicle in space, including oxygen and sleeping accommodation for two astronauts". I'd have asked for more!  |
Proponent
Member Posts: 59
From: London
Registered: Oct 2008
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posted 01-28-2010 01:13 AM
Is it possible that had someone been keeping a close eye on power consumption of the heater in the damaged oxygen tank, the failed thermostatic switch could have been detected before the explosion and the explosion prevented?This is not intended to be a criticism of the fantastic team involved; obviously in asking this question I have the enormous advantage of hindsight. Another question arises: suppose the tank problem had been identified in advance of an explosion. Could the lunar-landing mission have proceeded? |
moorouge
Member Posts: 2458
From: U.K.
Registered: Jul 2009
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posted 01-28-2010 04:53 AM
The answer is that this wouldn't have happened. See item 7 in my original posting.A more pertinent question is why the fact that they had to boil off the oxygen during the testing prior to launch didn't ring any alarm bells. |
kr4mula
Member Posts: 642
From: Cinci, OH
Registered: Mar 2006
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posted 01-28-2010 11:25 AM
quote:
Originally posted by Proponent:
Another question arises: suppose the tank problem had been identified in advance of an explosion. Could the lunar-landing mission have proceeded?
That was my question, too. Say one of the geniuses in the backroom (or maybe even Sy!) noticed erratic readings, they and the engineering guys did some investigating, and they figured out there was a problem. Could they have finished the mission without doing a cryo stir on that tank? Maybe pull a breaker or whatever to kill power to the heater, too? From what I remember, those stirs were more to ensure correct readings on tank levels than for function. |
Sy Liebergot
Member Posts: 501
From: Pearland, Texas USA
Registered: May 2003
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posted 01-28-2010 01:59 PM
Guys, You’re driving me crazy!  The tank heaters were not on continuously, the thermostat switch that was fused closed pre-launch would not have opened (operated) until the internal tank temp reached plus 80 degrees F (nearly empty). Tank temp at the time of the explosion was minus 192 degrees F, and about 78% quantity. The change to an explosion took only a few seconds. There was nothing erratic to see, except the failure of O2 Tank 2 quantity, which had failed earlier. As Moorouge stated, "A more pertinent question is why the fact that they had to boil off the oxygen during the testing prior to launch didn't ring any alarm bells." I believe that it would have taken six weeks to change out the tank set. Go fever probably helped rationalize that the Fill/Drain line had no in-flight function. And yes, we could have done without the daily cryo stir. All in my book. |
Lou Chinal
Member Posts: 1332
From: Staten Island, NY
Registered: Jun 2007
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posted 01-28-2010 08:18 PM
I agree with the above posts. For awhile the ground was thinking, "it was an instrument problem."I equate it to the NYC Fire Dept. planning for a plane crash into each tower - simultaneously. I mean that just couldn't happen(ed). |
Proponent
Member Posts: 59
From: London
Registered: Oct 2008
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posted 01-28-2010 08:25 PM
Sy Liebergot himself! I'm sure I speak for all of us when I say that we are honored! quote:
Originally posted by Sy Liebergot:
The tank heaters were not on continuously, the thermostat switch that was fused closed pre-launch would not have opened (operated) until the internal tank temp reached plus 80 degrees F (nearly empty). Tank temp at the time of the explosion was minus 192 degrees F, and about 78% quantity.
Thanks much; I had incorrectly assumed that, regardless of the quantity level, in normal operation the heater would cycle on and off the way household heating does. |
Obviousman
Member Posts: 438
From: NSW, Australia
Registered: May 2005
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posted 01-28-2010 09:32 PM
Like I said - read Sy's book. He suffered nightmares after the incident, playing out different scenarios, what he could have done differently.It was his subconscious telling him (correctly) "Listen dummy - you didn't do anything wrong, and you couldn't have prevented it!". According to Sy, the nightmares stopped when he realised this.
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Sy Liebergot
Member Posts: 501
From: Pearland, Texas USA
Registered: May 2003
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posted 01-29-2010 04:55 PM
quote:
Originally posted by Proponent:
I had incorrectly assumed that, regardless of the quantity level, in normal operation the heater would cycle on and off the way household heating does.
You are correct Proponent. The heaters were controlled by an automatic pressurization system that changed the cryo state to a gas and maintained that gas within a pressure range. So, the tank heaters did cycle on and off, as required. The crew could operate the heaters manually if required, as during tank quantity balancing. |
Spacepsycho
Member Posts: 819
From: Huntington Beach, Calif.
Registered: Aug 2004
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posted 02-01-2010 01:58 PM
I'm curious why nobody mentioned the fact that Beech Aerospace installed a 28 volt thermo switch, instead of the upgraded specs calling for the switch to be a 65 volt unit? Talk about a stupid oversight, in my opinion, that's the key element in this failure, not the O2 tank defect. It seems to me if Beech had done their job, even with the filler tube defect in the O2 tank, there wouldn't have been the 1000 degrees necessary to ignite the oxygen. I spoke to Glynn Lunney about this subject at the Apollo 13 event at the San Diego Air and Space Musuem and what he had to say was an incredible addition to the story that hasn't been discussed. |
Sy Liebergot
Member Posts: 501
From: Pearland, Texas USA
Registered: May 2003
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posted 02-01-2010 03:41 PM
If you read the Chonology of the Failure in my book, you have to come to the conclusion that there were more than one key element. So, what was the incredible addition that Glynn said? |
garymilgrom
Member Posts: 1966
From: Atlanta, GA
Registered: Feb 2007
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posted 02-01-2010 05:17 PM
I echo what Sy asked - this sounds interesting. |
Spacepsycho
Member Posts: 819
From: Huntington Beach, Calif.
Registered: Aug 2004
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posted 02-02-2010 09:35 AM
The 10-15 minute conversation I had with Glynn was facinating, albeit too short given the venue. I suggest when you meet Glynn, ask him about it. By the way, I'm curious why nobody commented on Beech Aerospace's failure to properly upgrade the thermo switch to 65 volts in the O2 tank. Every other contractor dealing with the CSM electric systems, upgraded their hardware properly. It seems they've been given pass for causing a catastrophic failure and almost killing the crew. From everything I've read, the 28 volt thermo switch fusing from 65 volts and causing the 1000 degree temp inside the O2 tank, was clearly the #1 cause for the explosion. While the filler tube defect showed a problem by being displaced, had it not been for Beech's screwup, this mission would have been successful. |
Sy Liebergot
Member Posts: 501
From: Pearland, Texas USA
Registered: May 2003
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posted 02-02-2010 09:54 AM
quote:
Originally posted by Spacepsycho:
I suggest when you meet Glynn, ask him about it.
I fail to understand why you won't share this new info with us. I'll just have to assume that it's non-existent. |
moorouge
Member Posts: 2458
From: U.K.
Registered: Jul 2009
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posted 02-02-2010 03:40 PM
quote:
Originally posted by Spacepsycho:
From everything I've read, the 28 volt thermo switch fusing from 65 volts and causing the 1000 degree temp inside the O2 tank, was clearly the #1 cause for the explosion. While the filler tube defect showed a problem by being displaced, had it not been for Beech's screwup, this mission would have been successful.
A query for Sy. Would the regular stir time in flight be long enough to short out the switches and char the insulation? My understanding is that it was the length of time time taken to boil off the oxygen during the test that was the vital part in the sequence leading to the explosion and this was only because of the misplaced fill/drain tube.Or would a cumulative effect be made leading to, perhaps, the same problem on the way home from the Moon? In that case, what would have been the chances of saving the crew? |
Sy Liebergot
Member Posts: 501
From: Pearland, Texas USA
Registered: May 2003
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posted 02-02-2010 06:50 PM
quote:
Originally posted by moorouge:
Would the regular stir time in flight be long enough to short out the switches and char the insulation?
No, each tank stir was only 1-2 minutes in duration. |
jasonelam
Member Posts: 691
From: Monticello, KY USA
Registered: Mar 2007
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posted 02-03-2010 02:54 AM
quote:
Originally posted by moorouge:
Or would a cumulative effect be made leading to, perhaps, the same problem on the way home from the Moon? In that case, what would have been the chances of saving the crew?
I would assume that if the same problem occurred any point after the LM landed would have resulted in the loss of the crew, especially if the crew was on the way home. Would that be correct? |
moorouge
Member Posts: 2458
From: U.K.
Registered: Jul 2009
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posted 02-03-2010 03:22 AM
Second thoughts on my second question if an explosion had happened after the LM had gone.I think the answer lies in working back from main chute deployment and calculating the capacity of the batteries to provide power for other necessary functions. I believe that these batteries had about 30 minutes of useful life so it would seem that the answer is that the CM could not function for very long on its own. |
Sy Liebergot
Member Posts: 501
From: Pearland, Texas USA
Registered: May 2003
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posted 02-03-2010 08:35 AM
Y'all need to research more documentation on your own or come to one of my lectures! Given the extent of the Apollo 13 failure, once the LM was powered up, and undocked, the crew would not have survived. If the failure had occurred during Apollo 8 (no LM), the CM would have run out of power in about three hours. re Three Entry Batteries at 40 a-h each: possibility here with an immediate powerdown and the closer to landing the failure occurred. But keep in mind the the CM powerup procedures took about three days to develop. |
moorouge
Member Posts: 2458
From: U.K.
Registered: Jul 2009
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posted 02-03-2010 09:17 AM
Very many thanks for the response Sy.From your answer it would seem to put the CM about 3 hours out from splash-down. There are a couple of further factors that occur to me. First, how long would the life support system sustain the crew? And second, would the CM have the capacity to make minor corrections to return to a safe re-entry trajectory by itself? I think I know the answers but would value your opinion. |
Sy Liebergot
Member Posts: 501
From: Pearland, Texas USA
Registered: May 2003
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posted 02-03-2010 03:11 PM
Life support system needed electricity for coolant pumps and cabin/suit loop fans (CO2 removal).It was pretty much accepted that the SPS was unusable from the explosion. Mid course corrections needed the nav system powered up. So not an option. By the way, did Spacepsycho ever post the incredible Apollo 13 additional revelation told to him by Glynn Lunney? |
moorouge
Member Posts: 2458
From: U.K.
Registered: Jul 2009
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posted 02-03-2010 03:55 PM
Once again very many thanks Sy. Was much as I suspected but it is comforting to have it confirmed. I shall stop pestering you now. |
Sy Liebergot
Member Posts: 501
From: Pearland, Texas USA
Registered: May 2003
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posted 02-03-2010 04:43 PM
You're most welcome. I expect to see you at one of my lectures if I'm ever invited across the pond. |
Dwight
Member Posts: 577
From: Germany
Registered: Dec 2003
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posted 02-04-2010 04:36 PM
At the risk of sounding like I endorse something which some may have ethical problems with, here's my ideal world, imagined only hypothesis.Given that by Apollo 13, public interest was seriously waning, there was something which could have propelled the Apollo 13 mission into the ueber-legendary status - and that would have been (ignoring of course power conservation measures) keeping the TV camera on during critical phases performed in the spacecraft. Moral and ethical considerations aside, it would have really given a window into how much ingenuity went into saving the crew. I realise this raises a lot of questions, but it would, without a doubt, have presented live TV in the absolute true meaning of the phrase. It would have gotten public interest to an unimaginable peak. But then again, given the gravity of the situation, it is only a hypothesis which we could bandy about post-mission, knowing that everything turned out OK. |
garymilgrom
Member Posts: 1966
From: Atlanta, GA
Registered: Feb 2007
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posted 02-04-2010 05:20 PM
Dwight - Interesting comment but due to the power needed by the TV I think the point is moot. |
Sy Liebergot
Member Posts: 501
From: Pearland, Texas USA
Registered: May 2003
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posted 02-04-2010 10:29 PM
quote:
Originally posted by Dwight:
Given that by Apollo 13, public interest was seriously waning...
Dwight, I seriously take issue with your "waning" comment. After only two lunar landings, public interest was seriously waning? It was waning only because the news media decided that. We must pay attention to how much influence the news media can have/has had on public attitudes. I address this problem in my lectures. |
moorouge
Member Posts: 2458
From: U.K.
Registered: Jul 2009
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posted 02-05-2010 02:34 AM
Sy has it right - again . I believe that the launch of '13' was restricted to a small square in corner of TV programmes. However, may I add one point. One of the mistakes admitted by NASA on the Apollo programme was that they seriously underestimated the need for a pro-active PR campaign. |
Sy Liebergot
Member Posts: 501
From: Pearland, Texas USA
Registered: May 2003
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posted 02-05-2010 07:35 AM
I absolutely agree, Moorouge. NASA really minimized publicity, but everything was so secret back in those days. Needed to keep everything from the Russians. Cripes, I had a Secret security clearance and the astronauts were cleared above Top Secret to Crypto. |
Space Cadet Carl
Member Posts: 225
From: Lake Orion, Michigan
Registered: Feb 2006
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posted 02-05-2010 11:31 AM
I recall there was still a great deal of interest in Apollo at my high school in 1970 around the time of Apollo 13. We talked about flipping the channel selector on our televisions, desperately trying to find any coverage we could. Things got better during Apollo 15 because of the fabulous Rover images. But Apollo 16 and Apollo 17 was pathetic in it's lack of network coverage. I recall seeing little one-minute video clips form A16 and Apollo 17 on the evening news. It drove me insane because the computer enhanced video was so spectacularly sharp and they would only show one lousy minute of it. |
Dwight
Member Posts: 577
From: Germany
Registered: Dec 2003
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posted 02-07-2010 07:43 PM
Hi Sy, I must admit based on what I have read over the years, I was under the impression that public interest had indeed fallen sharply by the time of the Apollo 13 flight. I certainly hope it wasn't as dramatic as documentaries and written works would have me believe, because quite honestly I find it hard to fathom that such a huge undertaking such as flying to the moon could be deemed as uninteresting or mundane so quickly.Regradless, I do feel that certain departments within NASA completely underestimated the power of live television from the moon. I think the first real "hammered home" moment came to them moments after the Apollo 12 TV mishap. As confirmed by numerous letters from the viewing public to NASA, alot of people were upset that there was no live (and color) TV for the majority of the A12 moonwalk. I guess the benefit of hindsight makes it easy for someone like me to pontificate from my armchair. Events such as the Apollo 7 Wally, Walt and Don show generated huge public interest, resulting in part to the acceptance that TV on the missions wasn'tr so bad after all. Thankfully the forward thinking people came to the rescue and the history and legacy of Apollo is preserved on videotape for future generations. |
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