🚀 go-pugleaf

In article <BzFxGA.xC.1@cs.cmu.edu> roberts@cmr.ncsl.nist.gov (John Roberts)
writes:
>While it wouldn't be fair to divide the cost of an entire Shuttle mission
>by maximum EVA time to get US EVA costs, I expect a more reasonable
>accounting method would still get a figure up in the millions of dollars
>per hour. Don't the EVA suits have a certain maximum number of hours they
>can be used per flight?
>John Roberts
>roberts@cmr.ncsl.nist.gov
>
   The suits have about 7 hours of oxygen in their primary O2 tanks,
and about the same amount in their secondary tanks under normal use
conditions.  But since the secondary tanks are meant to serve as
a supplement should the suit get a leak or the primary system fail,
this does not give the astronaut 14 hours of oxygen.  The real limiting
consumable is battery life, about 8 hours.  But this limit is for each
EVA.  Once the suits are hooked up to the orbiter, the oxygen, water, and
batteries are filled and recharged.  (The secondary O2 tanks are not 
rechargable because they have 3 times the pressure as the primary tanks.)