Matt wrote:
Why was there not, in the original design, or at least in the post-
Challenger mods when they added the ACES suit and the bailout system,
an air supply (say, a 60-minute bottle mounted on each seat) adequate
to have everyone sealed in pressure suits throughout the reentry
procedure? Crewmembers would still have their PEAPs as an emergency
backup.


They pointed out the problem with the suits and the onboard oxygen
system in the report.
When the suits are buttoned up and pressurized, the exhaled air enters
the crew module.
Since this is a pure oxygen pressurization system and the exhaled air
still has a lot of oxygen in it, the cabin oxygen content starts to
climb, leading to a fire hazard.
That's why the astronauts do their reentry with their visors up, and are
only to lower them in the event of trouble.
At least some of them did a suit pressurization test prior to reentry,
but then raised their visors again and went back to cabin air.
Of course pressurizing your suit isn't going to work if you don't have
your gloves on, so that was a major slip-up in regards to crew safety,
in that three of them didn't have their gloves on when things started to
go wrong (as well as one not having their helmet on); it also brings up
a possible design problem - when the Shuttle was designed the intention
was to have the crew fly without pressure suits...i.e. no gloves.
Are the switches and buttons on the control panel too small to be easily
manipulated while you are wearing pressure suit gloves?

Pat