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Author
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Topic: Handrail use outside Apollo lunar module
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rasorenson
Member Posts: 103
From: Santa Clara, CA, USA
Registered: Nov 2009
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posted 09-15-2020 10:14 PM
   
Recalling the planned EVA of Rusty Schweikart to move from the lunar module porch toward the command module on Apollo 9, I checked to remind myself that all LMs on landing missions had the same handrail, which fortunately was never used. I don't recall ever seeing printed material about how the EVA rail would be used in lunar orbit if for some reason the docking tunnel was blocked after liftoff from the surface. Any references out there? Would they have ventured to save the surface sample boxes? |
Robert Pearlman
Editor Posts: 44663
From: Houston, TX
Registered: Nov 1999
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posted 09-15-2020 11:27 PM
The procedures for an emergency vehicle transfer (EVT) can be seen, for example, on page 21 of the Apollo 14 lunar module cue cards (as referenced in this earlier topic). The steps make several references to the EVA handrail. |
oly
Member Posts: 1099
From: Perth, Western Australia
Registered: Apr 2015
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posted 09-15-2020 11:56 PM
Figure 20a and 20b of the Apollo 9 press kit details the EVA crew transfer using the handrail (20b). There would need to be an evaluation of time available to do the transfer and the reason why an EVA transfer was required, ideally all sample return boxes would be transferred, along with other items needed for ballast (if required). If it was determined to be time critical then the priority would be given to crew survival at the detriment of sample returns. As referenced in the other thread, the Apollo 11 checklist references using the PLSS, however, these were left on the lunar surface, so it appears that contingency plans change between missions. |
Space Cadet Carl
Member Posts: 240
From: Lake Orion, Michigan
Registered: Feb 2006
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posted 09-17-2020 04:00 PM
Interesting point. If the PLSS's were jettisoned onto the lunar surface, I'm assuming there was an oxygen hose inside the CM that could reach all the way over to the interior of the LM? |
Ronpur
Member Posts: 1228
From: Brandon, Fl
Registered: May 2012
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posted 09-17-2020 09:33 PM
The top section of the backpack, the OPS, was kept. It would have been used to supply oxygen, 10 to 30 minutes worth if I remember correctly, for the transfer. |
mmmoo
Member Posts: 563
From: London, England
Registered: May 2001
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posted 09-18-2020 05:13 AM
Here is the Apollo 15 flown to lunar surface Contingency EVT cue card. It shows all the steps needed to conduct an Extra Vehicular Transfer in case of a docking or tunnel problem.The OPS units were used for oxygen (and for the deep space EVA). Side 2 mentions the commander and then the lunar module pilot should egress feet first, pull themselves along the lunar module handrails then ingress head first into the command module. |
LM-12
Member Posts: 3477
From: Ontario, Canada
Registered: Oct 2010
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posted 09-18-2020 07:27 AM
In the Apollo 14 cue cards mentioned in the earlier thread, the lunar module pilot enters the command module feet first. |
mmmoo
Member Posts: 563
From: London, England
Registered: May 2001
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posted 09-18-2020 07:35 AM
You are correct, it seems the commander enters the command module head first, then the lunar module pilot enters feet first. |
oly
Member Posts: 1099
From: Perth, Western Australia
Registered: Apr 2015
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posted 09-18-2020 10:28 PM
quote:
Originally posted by Ronpur:
The top section of the backpack, the OPS, was kept. It would have been used to supply oxygen, 10 to 30 minutes worth if I remember correctly, for the transfer.
The Apollo crews for the latter missions used an umbilical to perform the EVA recovery of film canisters which was long enough to reach along the service module. The OPS did have 30 minutes of emergency oxygen supply, but a crew transfer would ideally use the same umbilical and reserve the OPS for backup/emergency. Commitment to use the OPS would be a last resort. Real time evaluation of the conditions requiring a crew EVA transfer would need to be done, just because the LM and CM could not dock together does not automatically mean that the crew transfer needed to be done in a hurry. There was also the capability during a lunar surface EVA for the astronauts to "buddy breath" by interconnecting suit hoses, which indicates that some kind of combination of hose and umbilical may have been possible. Perhaps multiple hoses can be joined together? This raises the possibility of the CM pilot connecting an umbilical and somehow passing it over to the LM, allowing an astronaut to switch between LM and CM systems, just as the EVA buddy breathing hose swap idea. Each of these would risk compromising the suit seal integrity. If the leak could not be easily rectified, the astronaut may have to commit to using the OPS. |
Henry Heatherbank
Member Posts: 260
From: Adelaide, South Australia
Registered: Apr 2005
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posted 09-19-2020 12:48 AM
quote:
Originally posted by mmmoo:
...it seems the commander enters the command module head first, then the lunar module pilot enters feet first.
Why the different entry modes into the CM? Would it really matter?
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Space Cadet Carl
Member Posts: 240
From: Lake Orion, Michigan
Registered: Feb 2006
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posted 09-19-2020 08:20 AM
quote:
Originally posted by oly:
Commitment to use the OPS would be a last resort.This raises the possibility of the CM pilot connecting an umbilical and somehow passing it over to the LM, allowing an astronaut to switch between LM and CM systems, just as the EVA buddy breathing hose swap idea.
Thanks, oly. Your response just added more thought to this interesting scenario. |
oly
Member Posts: 1099
From: Perth, Western Australia
Registered: Apr 2015
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posted 09-20-2020 12:09 AM
Note that when using the OPS during a lunar surface EVA emergency, it was rated to provide 30 minutes of breathing oxygen and suit cooling, the OPS duration could be extended (up to 90 minutes) when using the buddy system piggyback of suit cooling from the partnered PLSS. This is because the OPS uses a continuous vent to space design to purge carbon dioxide, heat, and water vapor. Why the crew had assigned orientations as they entered the CM may have something to do with fitting all three crew inside the CM and still be able to manipulate the hatch from an open to closed position. An astronaut entering the CM headfirst may be able to maneuver under the instrument panel and into the equipment bay unassisted, leaving room to operate the hatch by the crew member entering feet first. |
LM-12
Member Posts: 3477
From: Ontario, Canada
Registered: Oct 2010
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posted 09-20-2020 01:27 AM
quote:
Originally posted by mmmoo:
to conduct an Extra Vehicular Transfer
I incorrectly referred to "EVT" as an emergency vehicle transfer in the earlier thread. The Apollo 9 press kit has a list of acronyms and abbreviations, but "EVT" is not on the list. |
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