[FPSPACE] emergency return to airlock

[Geert Sassen]

If I remember correctly the Apollo system allowed two suits to exchange 
cooling water, not air. An emergency oxygen supply was carried in the 
OPS unit, on top of the PLSS backpack, however if the PLSS failed the 
suit would be without cooling water and would quickly overheat, so they 
had a system with the option to share coolingwater via a hose. Offcourse 
this system worked best while sitting in the rover, walking with it 
would be somewhat slow.

As far as I know none of the present EVA suits has an option to share 
either cooling water, electricity, or oxygen between suits. I am still 
trying to find out what has been the biggest 'distance' (not in meters, 
but in 'time required to get back') from the airlock but I don't think 
it has ever been more then 30 minutes, not even on the MMU missions.

Regards,

Geert.

Jim Oberg wrote:
> On Apollo they also had a buddy system for supplying air
> from one suit to another. Good point on this threat exposure.
>
>
> ----- Original Message ----- 
> From: "Geert Sassen" <geert at navtools.nl>
> To: "Chris Faranetta" <cfaranetta at spaceadventures.com>
> Cc: <fpspace at friends-partners.org>
> Sent: Friday, November 02, 2007 6:36 AM
> Subject: Re: [FPSPACE] Critical spacewalk Saves of the Past
>
>
>   
>> Hubble repairs were certainly spectaculair and very ingenious, however 
>> these were more or less planned long before the mission started, same 
>> with the solar max. With the Skylab, Salyut, and Mir repairs, as well as 
>> with the present ISS EVA we are talking about EVA's and repairs which 
>> were not planned and (more or less) have to be improvised and designed 
>> during the mission, which is a very difficult thing to do as you are 
>> working with astronauts/cosmonauts who are asked to do something for 
>> which they did not receive exact training before the mission.
>>
>> In my opinion one of the most dangerous items is that Parazynski will be 
>> very far away from the airlock, too far in fact to bring him back to 
>> safety should his spacesuit fail (his emergency supply lasts only 30 
>> minutes which will not be sufficient). I don't know whether there have 
>> ever been EVA's where this safety-feature was waved away (even during 
>> the moon-rover missions, they were always within 30 minutes driving of 
>> the LM, only if both the rover and a PLSS failed they would have a big 
>> problem), I have great faith in mission control and the guys planning 
>> this repair but they certainly work very close to the edge...