Design Article
Chronicles of Grumman's 1960s Lunar Excursion Module development
Suzanne Deffree
3/1/2012 6:52 PM EST
A perilous situation
A perilous situation
Bracco shared an interesting story involving the Apollo 13 crew in a perilous situation in outer space and the heroic efforts of the Grumman designers along with NASA Mission Control experts to avert a lethal situation and safely return these men to Earth. At five and a half minutes after liftoff, astronauts Jack Swigert, Fred Haise, and James Lovell felt a little vibration. The center engine of the massive Saturn S-II stage shut down two minutes early, causing the remaining four engines to burn 34 seconds longer than planned. The S-IVB third stage was forced to burn nine seconds longer to put Apollo 13 in orbit.
At 55 hours and 46 minutes, as the crew finished a 49-minute TV broadcast showing how comfortably they lived and worked in weightlessness, Lovell said, "This is the crew of Apollo 13 wishing everybody there a nice evening, and we're just about ready to close out our inspection of Aquarius [the LEM] and get back for a pleasant evening in Odyssey [the command module]. Good night." Nine minutes later, oxygen tank number 2 blew up, causing oxygen tank number 1 to also fail. Approximately 200,000 miles from Earth, the Apollo 13 command module's normal supply of electricity, light, and water was lost.
The message came in the form of a sharp bang and vibration. Swigert saw a warning light that accompanied the bang and said, "Houston, we've had a problem here." Lovell came on and told the ground that it was a main B bus undervolt. The time was 2108 hours on April 13.
Next, the warning lights indicated the loss of two of Apollo 13's three fuel cells, which were the spacecraft's prime source of electricity. With warning lights blinking, one oxygen tank appeared to be completely empty, and there were indications that the oxygen in the second tank was rapidly being depleted. The third lunar landing attempt mission was aborted after rupture of the service module oxygen tank.
Power was a concern. There were 2181 ampere hours in the LEM batteries. Ground controllers carefully worked out a procedure that enabled LEM power to be used to charge the command module batteries.
With the power-producing service module damaged due to an explosion, an innovative idea involving a roll of duct tape and a technical manual saved the crew from carbon-dioxide poisoning. The crew was instructed to rip out plasticized pages of an onboard manual and get the duct tape ready so they could attach the command module's lithium hydroxide canisters (used to remove carbon dioxide from the cabin atmosphere) to the LEM environmental system using the square canisters from the command module. All noncritical systems were turned off, and energy consumption was reduced to a fifth of normal. Twenty percent of the LEM electrical power was left when Aquarius was jettisoned.
As part of an electrical close call during the mission, one of the control-module batteries vented with such force that it momentarily dropped off the line. Had the battery failed, there would be insufficient power to return the ship to Earth. Luckily, there was no failure.
Grumman had greatly overdesigned the LEM so that in this situation it was able to keep the crew alive until the ship could circle around the moon in a "sling-shot" path to propel it back toward Earth for a safe entry into the atmosphere and safe splashdown in the ocean. The Grumman designers were sure of the LEM's capabilities. The mission was classified as a "successful failure" because of experience gained while rescuing the crew.
A perilous situation
Bracco shared an interesting story involving the Apollo 13 crew in a perilous situation in outer space and the heroic efforts of the Grumman designers along with NASA Mission Control experts to avert a lethal situation and safely return these men to Earth. At five and a half minutes after liftoff, astronauts Jack Swigert, Fred Haise, and James Lovell felt a little vibration. The center engine of the massive Saturn S-II stage shut down two minutes early, causing the remaining four engines to burn 34 seconds longer than planned. The S-IVB third stage was forced to burn nine seconds longer to put Apollo 13 in orbit.
At 55 hours and 46 minutes, as the crew finished a 49-minute TV broadcast showing how comfortably they lived and worked in weightlessness, Lovell said, "This is the crew of Apollo 13 wishing everybody there a nice evening, and we're just about ready to close out our inspection of Aquarius [the LEM] and get back for a pleasant evening in Odyssey [the command module]. Good night." Nine minutes later, oxygen tank number 2 blew up, causing oxygen tank number 1 to also fail. Approximately 200,000 miles from Earth, the Apollo 13 command module's normal supply of electricity, light, and water was lost.
The message came in the form of a sharp bang and vibration. Swigert saw a warning light that accompanied the bang and said, "Houston, we've had a problem here." Lovell came on and told the ground that it was a main B bus undervolt. The time was 2108 hours on April 13.
Next, the warning lights indicated the loss of two of Apollo 13's three fuel cells, which were the spacecraft's prime source of electricity. With warning lights blinking, one oxygen tank appeared to be completely empty, and there were indications that the oxygen in the second tank was rapidly being depleted. The third lunar landing attempt mission was aborted after rupture of the service module oxygen tank.
Power was a concern. There were 2181 ampere hours in the LEM batteries. Ground controllers carefully worked out a procedure that enabled LEM power to be used to charge the command module batteries.
With the power-producing service module damaged due to an explosion, an innovative idea involving a roll of duct tape and a technical manual saved the crew from carbon-dioxide poisoning. The crew was instructed to rip out plasticized pages of an onboard manual and get the duct tape ready so they could attach the command module's lithium hydroxide canisters (used to remove carbon dioxide from the cabin atmosphere) to the LEM environmental system using the square canisters from the command module. All noncritical systems were turned off, and energy consumption was reduced to a fifth of normal. Twenty percent of the LEM electrical power was left when Aquarius was jettisoned.
As part of an electrical close call during the mission, one of the control-module batteries vented with such force that it momentarily dropped off the line. Had the battery failed, there would be insufficient power to return the ship to Earth. Luckily, there was no failure.
Grumman had greatly overdesigned the LEM so that in this situation it was able to keep the crew alive until the ship could circle around the moon in a "sling-shot" path to propel it back toward Earth for a safe entry into the atmosphere and safe splashdown in the ocean. The Grumman designers were sure of the LEM's capabilities. The mission was classified as a "successful failure" because of experience gained while rescuing the crew.
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GeniusEE
3/1/2012 8:56 PM EST
Was he also the guy who made the bad decision on the CO2 scrubbers to not use compatible componenets between the CM and LEM, almost killing the crew? Selective-recall heroism - let's balance it and hear about screwups in this kind of forum, which are actually more useful to engineers than building pedestals of awe for plebes.
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patrick.mannion
3/2/2012 1:59 PM EST
Hi Andy, your point is valid (but you should avoid name-calling, in general: there's as much to be learned (if not more) from what didn't work as from what actually did work. Edison's work on bulb filaments is a great example of that. We would definitely be keen to do a series on mistakes and what was learned from them. In the case you mention above in your comment, the lesson may well just be simply 'don't do that', but there are plenty more mistakes that can and have important lessons to teach. Are you interested in kicking off a series on that? It would indeed be very helpful and useful (so long as we avoid calling people 'plebes'.
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WA2PYX
3/2/2012 3:11 PM EST
The decision to use NiCd batteries was greatly influenced by the late(R.Adm.)George Klaus of the Grumman Electronic Systems Center. He deserves some of the credit for the successful recovery of Apollo 13. I worked for him and still have a couple of the test NiCd batteries as souvenirs. Those were interesting times.
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GregB1
3/2/2012 3:47 PM EST
Yes Grumman was the prime contractor but there were I'm sure many sub contractors that are never mentioned. My dad worked long and hard on the LEM for Hughes Aircraft. Makes me upset that these guys get al the glory when in fact it was a much larger team effort.
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anonymous user
3/2/2012 6:52 PM EST
May God bless ALL of the fine men and women who worked on the US Space Program, and allowed us to fulful President Kennedy's words to land a man on the moon before the decade's end. The engineers, technicians, and brave men and women who trained as astronauts, got us to the moon before the Soviet Union, and helped us win the Cold War. I am afraid that with the discontinuation of the Space Shuttle, that level of technical expertise will now be lost, and we will never be able to achieve such technical prowess ever again. Thanks again for all your efforts!
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anonymous user
3/2/2012 6:54 PM EST
May God bless ALL of the fine men and women who worked on the US Space Program, and allowed us to fulful President Kennedy's words to land a man on the moon before the decade's end. The engineers, technicians, and brave men and women who trained as astronauts, got us to the moon before the Soviet Union, and helped us win the Cold War. I am afraid that with the discontinuation of the Space Shuttle, that level of technical expertise will now be lost, and we will never be able to achieve such technical prowess ever again. Thanks again for all your efforts!
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oldtimer8080
3/3/2012 2:00 AM EST
It might be interesting to have someone check into the history of the " Blue Cube " and the surrounding Ford Aerospace and GTE plants in the SFBA. I know AMD supplied MIL-SPEC parts for quite a few projects ( My job at AMD )and I had a good idea of what went on inside the cube.
Onizuka Air Force Station
The Wiki article only scratches the surface of what went on. My " Let's Move Some Chairs " buddies didn't talk about what they did...
( that is, if the NRO & NSA lets you )
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anonymous user
3/5/2012 6:38 PM EST
The "Spider" episode of the HBO series "From the Earth to the Moon" was just about my favorite of the series. I'm sure it has its made for TV inaccuracies, but the development details they put in showed that somebody with a lot of love for what happened was on the writing staff somewhere. The hatchway part reminded me of that.
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anonymous user
3/5/2012 9:11 PM EST
Of course there were many thousands employed by subcontractors to Grumman who made valuable contributions. I know my Dad had dozens of job shoppers during the Lunar Test Article (LTA) thermal vacuum testing, which he was responsible for as Test Engineering Chief for Grumman in Houston.
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anonymous user
3/5/2012 11:18 PM EST
I recently had the opportunity fo visit The Cradle of Avation Museum and the Grumman display of the Lunar Excursion Module (LEM). The entire history of the developement and the flight is amazing. The 60's era developeers were real pioneers and deserve recognition in our country's history. Thanks to these men and women for their extreme efforts! God Bless.....
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anonymous user
3/6/2012 8:20 PM EST
I was one of the techs. on the Saturn V program and I did watch the live feed of the first step on the moon.
CHK
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anonymous user
3/12/2012 1:59 PM EDT
n 1966/67 I worked for North American Aviation as a "Ground Support Technician" and was on Pad during the build up and Lauch of the first "LEM" from Cape Kennedy Fl. I remember the Boys from Bethspage NY were the Penny Pitchingist bunch I have ever seen. lol We built up Pad 37 just for the first Launch of the LEM. It was atop of an UpRated Saturn 1B.... A beautiful Launch and a beautiful Recovery. Those were the days!
John W Lynch
SWORD Electronics LLC
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