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Author
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Topic: Apollo lunar rover failures and contingencies
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KenDavis
Member Posts: 187
From: W.Sussex United Kingdom
Registered: May 2003
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posted 03-27-2012 03:35 PM
   
Did NASA have contingency plans in case the Lunar Rover became inoperable? If so how would the EVAs have changed to still achieve as much as possible or would alternative plans have been made if the situation arose?What would have happened on Apollo 17 if they hadn't been able to fix the broken dust guard? |
jtheoret
Member Posts: 358
From: Albuquerque, NM USA
Registered: Jul 2003
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posted 03-27-2012 09:06 PM
Charlie Duke told me that they weren't allowed to drive more than 4 miles away from the LM in any one direction because that was the distance NASA believed they could walk back if they had to. |
Paul78zephyr
Member Posts: 678
From: Hudson, MA
Registered: Jul 2005
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posted 03-28-2012 08:28 AM
Four miles! I cannot imagine a crew on foot in their suits walking 4 miles. - Was this ever simulated on earth?
- How long was it estimated that a 4 mile walk back would take?
- How far was the furthest 'walk' on previous Apollo lunar EVAs?
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jtheoret
Member Posts: 358
From: Albuquerque, NM USA
Registered: Jul 2003
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posted 03-28-2012 10:50 AM
Al Shepard and Ed Mitchell walked the farthest during Apollo 14. They walked just short of a couple of miles I think and took about four and a half hours but they were sampling and not just trying to get back to the LM in a hurry. No idea how long it was estimated to go four miles, or answers to other questions, but they're good ones. |
Robert Pearlman
Editor Posts: 43576
From: Houston, TX
Registered: Nov 1999
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posted 03-28-2012 10:54 AM
NASA's Apollo 14 summary includes the following: Shepard set a new distance-traveled record on the lunar surface of approximately 9,000 feet. Converting, 9,000 feet is 1.7 miles. |
Jay Chladek
Member Posts: 2272
From: Bellevue, NE, USA
Registered: Aug 2007
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posted 03-28-2012 12:43 PM
Was that round trip or one way? |
KenDavis
Member Posts: 187
From: W.Sussex United Kingdom
Registered: May 2003
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posted 03-28-2012 01:14 PM
Thanks all. My point was EVAs were planned given the crew could travel 4 miles. If at the start of an EVA the LRV was found to be unusable was there already a contingency EVA planned with a nearer target? |
Robert Pearlman
Editor Posts: 43576
From: Houston, TX
Registered: Nov 1999
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posted 03-28-2012 01:40 PM
There is mention in the Apollo 17 preliminary science report that the choice of landing sites (between Gassendi, Alphonsus and Taurus-Littrow) considered the possibility that the LRV would fail. If the lunar module were to land down range of the nominal ellipse, it was likely that, even if the landing were successful, the crewmen would not be able to traverse to the prime objective (the central peaks), particularly if there were a failure of the lunar roving vehicle (LRV). These problems were deemed sufficient that the NASA Lyndon B. Johnson Space Center (JSC) considered Gassendi unacceptable as an Apollo 17 site....as in the case of Alphonsus, it was determined that the prime objective at Taurus-Littrow was achievable on a walking mission (LRV failure), even if the landing were made outside the nominal ellipse. And just to touch on a side topic... quote:
Originally posted by jtheoret:
...they weren't allowed to drive more than 4 miles away.
Apparently, it was six miles. From the Apollo 16 press kit: The maximum distance the LRV will be permitted to range from the lunar module will be approximately 9.4 kiiometers (5.9 miles), the distance the crew could safely walk back to the LM in the unlikely event of a total LRV failure. This walkback distance limitation is based upon the quantity of oxygen and coolant available in the astronauts' portable life support systems. This area contains about 292 square kilometers (113 square miles) available for investigation, 10 times the area that can be explored on foot. |
MCroft04
Member Posts: 1647
From: Smithfield, Me, USA
Registered: Mar 2005
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posted 03-28-2012 06:24 PM
Schmitt is quoted in Footprints in the Dust "You could go six, ten kilometers an hour quite easily. If I had had a couple ski poles, I could have possibly gotten up to about fifteen and held that for some time. I think I could have outrun the Rover!" The question is how long could he have kept up that pace? |
moorouge
Member Posts: 2458
From: U.K.
Registered: Jul 2009
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posted 03-29-2012 02:14 AM
Though this thread has concentrated on the Rover, wasn't the main consideration the time/distance the 'buddy system' could support a suit failure? |
Jim Behling
Member Posts: 1488
From: Cape Canaveral, FL
Registered: Mar 2010
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posted 03-29-2012 12:41 PM
No, that is two separate failures. There was a limit for walking-only EVAs and a limit with the rover. They wouldn't plan for a rover failure and then a PLSS failure. |
bwhite1976
Member Posts: 283
From: Belleville, IL
Registered: Jun 2011
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posted 03-29-2012 09:10 PM
Duke indicates in his book "Moonwalker" (pages 148-149) that he and Young weren't happy with the five mile maximum distance rule for the Rover. To prove management wrong, they jogged around in circles for 10 miles in full moon suit and backpack in a special sling that simulated the one-sixth gravity. It took three hours!! Despite proving it could be done, the 5 mile rule remained. |
LM-12
Member Posts: 3324
From: Ontario, Canada
Registered: Oct 2010
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posted 10-13-2014 01:08 PM
Here are contingency walking EVA traverse maps for the Apollo 15 and Apollo 16 landing sites.On Apollo 15, Hadley Rille was the planned walking traverse destination on EVA-2. Some travel times: - LM to Station A (1:10) on EVA-1
- LM to Station D (0:34) on EVA-2
- LM to Station G (1:19) on EVA-3
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LM-12
Member Posts: 3324
From: Ontario, Canada
Registered: Oct 2010
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posted 10-14-2014 09:29 AM
The ALSJ has this Apollo 17 walking traverse map. |
LM-12
Member Posts: 3324
From: Ontario, Canada
Registered: Oct 2010
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posted 10-23-2014 06:46 AM
Also on Apollo 17, there is this interesting one-man LRV contingency traverse map. |
Fra Mauro
Member Posts: 1624
From: Bethpage, N.Y.
Registered: Jul 2002
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posted 10-31-2014 01:48 PM
I guess that was in case one crewman had a minor injury or cold and at least some science could be gained. It would have been an interesting EVA to say the least. Would NASA even have allowed one man to venture out by himself for a few hours? |
Lou Chinal
Member Posts: 1332
From: Staten Island, NY
Registered: Jun 2007
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posted 10-31-2014 02:17 PM
As I remember it, the original plan was to have one man remain in the LM. Only one astronaut would venture out at a time. |
Headshot
Member Posts: 891
From: Vancouver, WA, USA
Registered: Feb 2012
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posted 10-31-2014 02:26 PM
Correct. The initial plans for lunar exploration involved only one astronaut on the lunar surface. I believe, originally, only the LM pilot was supposed to leave the spacecraft while the commander remained inside. I do not know when that scenario changed. |
LM-12
Member Posts: 3324
From: Ontario, Canada
Registered: Oct 2010
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posted 10-31-2014 02:30 PM
Would the LMP have done a one-man LRV contingency EVA? A remote possibility perhaps. I have never seen any training photos showing the LMP in the left seat. |
Lou Chinal
Member Posts: 1332
From: Staten Island, NY
Registered: Jun 2007
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posted 10-31-2014 04:24 PM
Grumman had a chart showing astronauts A and B. I don't believe they or NASA ever identified A or B. This was when the LM was still called the Luna Excursion Module. |
moorouge
Member Posts: 2458
From: U.K.
Registered: Jul 2009
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posted 10-31-2014 05:29 PM
quote:
Originally posted by Headshot:
Correct. The initial plans for lunar exploration involved only one astronaut on the lunar surface. I believe, originally, only the LM pilot was supposed to leave the spacecraft while the commander remained inside. I do not know when that scenario changed.
Isn't this the origin of the Armstrong/Aldrin disagreement?
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schnappsicle
Member Posts: 396
From: Houston, TX, USA
Registered: Jan 2012
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posted 11-02-2014 05:44 PM
The Armstrong/Aldrin argument wasn't much of an argument. While Aldrin was busy trying to get his footprint to be the first one on the moon, Armstrong left the decision up to the mission planners. Besides, the hatch door swung towards the LMP's side of the LM, which basically put en end to any argument Aldrin, or his father, might have had. |
schnappsicle
Member Posts: 396
From: Houston, TX, USA
Registered: Jan 2012
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posted 11-02-2014 05:50 PM
Getting back to the original question, it's hard for me to imagine anyone walking 6 miles on the moon. As others have stated here before, the Apollo 14 astronauts had more than their share of problems navigating the 1.4 miles to the rim of Cone Crater. Of course, they had to take a specific path up and down the hummocks on the way there and got lost on more than one occasion, but its still a good indicator of exactly how hard it is to walk vs. drive on the moon.On the other side of the argument, the Apollo crews who drove the Rover spent a lot of time in elevation above the LM. That might have made the trip back to the LM considerably easier than any of us realize. Maybe that's why the walk back distance changed from one mission to another. |
mjanovec
Member Posts: 3811
From: Midwest, USA
Registered: Jul 2005
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posted 11-04-2014 04:31 PM
quote:
Originally posted by schnappsicle:
Getting back to the original question, it's hard for me to imagine anyone walking 6 miles on the moon.
I imagine it would less of a "walk" and more of a running "hop," especially if it was an emergency situation where they had to return to the LM before their consumables ran out. One assumes they wouldn't be dragging along a lot of equipment or samples in this scenario. The astronauts could build up a good speed by hopping. I seem to recall one of them even saying that if you got the rythym just right, you got enough hang time above the surface that you were able to effectively "rest" between hops. The difference with Apollo 14 is that they dragging along equipment as they walked. That definitely took more effort and was a much slower process. |
Paul78zephyr
Member Posts: 678
From: Hudson, MA
Registered: Jul 2005
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posted 03-20-2017 05:27 PM
Did NASA impose any additional operational limitations on the Apollo 15 crew during the time that their lunar rover vehicle had inoperable front wheel steering? Did anyone ever determine why the front steering was inoperable during the first EVA but began working again prior to the second EVA? |
schnappsicle
Member Posts: 396
From: Houston, TX, USA
Registered: Jan 2012
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posted 03-22-2017 09:20 AM
My recollection is that the steering problem on 15 had no effect on the mission planning or traverses. They still had rear wheel steering and could go where ever they wanted. Their turning ability was only slightly limited.The front wheel steering still wasn't working when they reentered the LM after EVA 1, and it was working when they went back out for EVA 2. No telling what caused the problem or how it was fixed. |
schnappsicle
Member Posts: 396
From: Houston, TX, USA
Registered: Jan 2012
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posted 03-22-2017 09:31 AM
All this contingency stuff has me thinking. What would the astronauts have done with the samples they collected on their traverse had the rover stopped working while they were still 6 miles from the LM? I'm sure they could have carried some material back to the LM, but I also remember several cases where their sample bags were so full that things started falling out of them. Did they take along any special bags in case they had to walk back to the LM, or were they limited by what they could fit in their side mounted sample bags? I know they put their samples in cases when they got back to the rover, but it seems like their hands would get rather sore and tired hopping across the moon carrying a brief case. |
moonguyron
Member Posts: 191
From: Trinity, FL USA
Registered: Jan 2011
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posted 03-27-2017 08:42 PM
In the unlikely event that astronauts had to walk back to the LM we should remember they would already have had at least one hand full. The rover had a communications package known as the Lunar Communications Relay Unit which provided all voice and TV between the astronauts and mission control through the low gain and high gain antennas. It is the Mylar covered box hanging off the front of the rover. If a walk back was required the LCRU along with the low gain antenna would have been pulled off the rover and hand carried by astronauts using the built in handle. The LCRU used almost as much power as the rover itself and therefore had its own battery packs that were replaced each day prior to the EVA to insure sufficient power available for contingencies. |
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