Henry Spencer wrote:
In article . com,
wrote:
Not saying the issue should be taken lightly, but wondering if it's
medium danger / severe annoyance level, or if it's seriously life
threatening on the ground it until it's fixed level?

Sort of in between. The suits could have kept them alive had the leak
been worse. But if anything further had gone wrong, it could have been a
bad day. The margins got uncomfortably thin.

Perhaps not "on the ground until it's fixed", but I'd say "urgent flights
only until it's at least understood".

I guess when they first noticed a leak during pre-undocking leak-check
they considered it to be small enough. They only spent 6 extra minutes
or so trying to fix it. This is just about enough time to open the
hatch, visually check that the rubber seal looks intact and there is no
FODs, then close the hatch and re-check it again. Maybe they simply
underestimated it. It it probably difficult to measure dp/dt accurately
with all those systems working. I don't know what the standard
procedure is when the hatch is leaking but there must be something you
can do, some sort of sealant can be applied or they may have spare
rubber seals or something like that. They could have spent more time on
it but that would've mess up their landing schedule.
BTW I think they have at least 2 backups for such leaks: portable O2
repress bottle and suit air. They did repress the cabin with O2 but I
don't know whether they had to switch completely to suit air.

I guess it was fairly serious but one-off like that kinked tube during
EVA. The right solution may be to inspect the seals more often while in
orbit, schedule more time on leak checks and don't breathe loudly while
doing it. They may also look at pressure sensors.