Space station future adrift (Soyuz purchase crisis)

(Derek Lyons) :

Earl Colby Pottinger wrote:

(Derek Lyons) :

There probably isn't a single company in the world that can do the
job, nor a consortium of the either. You are seriously delusional as
to how complex a 'simple' taxi/lifeboat is.

No, I am not.

Yes, you are. The mere statement that you think that Rutan or anyone
else can do so 'in two years' is shining proof of just that.

I am quite aware how stupidly complex NASA or the ESA can make
such a craft.

Ignorant bigotry. (As Henry pointed out - It took NASA much longer
than two years to fly the Gemini, and that was back in it's glory days
*and* with a spacecraft considerably less sophisticated and capable
than Soyuz.)

And that was when it have to learn everything from zero first. Today we have
access to a lot of that data without having to do costly research because
NASA and others recorded it for us to use. Second many materials needed have
to be invented/refined, today you just order them. The methods to build with
those materials again needed to be developed, today you send off a CAD file
and have it made for you. Computers, Navigation, Communication and Life
support were all things NASA and others needed to develop from almost nothing
to meet thier needs. Today, if you have the money they are just a phone call
away. The hardest thing to buy today seems to be the spacesuit itself, not
suprising considering it is usually a custum design item.

However if you had read the lifeboats in space thread you
would realize a simple float untill rescue lifeboat does not need to be
complex.

However, if you read this thread, you would realize we are talking
about a Soyuz replacement, not a (hypothetical and non-existent) craft
that can float around until rescued by (also hypothetical and
non-existent) another craft.

Yes, you are right here. This is clearly my mistake in mixing up threads.
Sorry about that - Again this is complete my fault sorry.

(And given that maritime lifeboats for
hostile enviroments are neither simple, nor cheap, one wonders about
your conclusions regarding space ones. It's *hard* to make things
that must wait quiescent for extended periods, and then function with
no checkout and a near guarantee of sucess.)

I would disagree except this is not the thread to do it in. Again my mistake
- maybe in another thread sometime?

Earl Colby Pottinger


--
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the time? http://webhome.idirect.com/~earlcp

Do I hear a MOOSE coming over the horizon?

Seriously, isn't it about time someone gave some serious thought to an
ultra-minimal personal re-entry scheme? Would the 'cure' actually
work without killing the 'patient'

P


Earl Colby Pottinger wrote:

(Derek Lyons) :

There probably isn't a single company in the world that can do the
job, nor a consortium of the either. You are seriously delusional as
to how complex a 'simple' taxi/lifeboat is.

In article ,
Phil Paisley wrote:
Do I hear a MOOSE coming over the horizon?
Seriously, isn't it about time someone gave some serious thought to an
ultra-minimal personal re-entry scheme?

Alas for the notion, that's not really what's called for. A lifeboat that
can carry at least two or three people is generally superior, not least
because it doesn't require donning a spacesuit on short notice (which is
all too likely to cause decompression sickness, aka the bends -- not only
painful but also deadly dangerous).
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

I wrote:
Seriously, isn't it about time someone gave some serious thought to an
ultra-minimal personal re-entry scheme?

Alas for the notion, that's not really what's called for. A lifeboat that
can carry at least two or three people is generally superior, not least
because it doesn't require donning a spacesuit on short notice (which is
all too likely to cause decompression sickness...

A friend has pointed out, in private mail, that you could do this with a
two-step emergency setup: an emergency refuge, which would provide life
support for a while and give time for prebreathing procedures, and then
a spacesuit-dependent bailout system.

While that's feasible, my gut feeling is that you're still better off with
a non-spacesuit lifeboat. And it does not strike me as substantially
harder to do, not when you deal with all the details.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

(Henry Spencer) wrote:
A friend has pointed out, in private mail, that you could do this with a
two-step emergency setup: an emergency refuge, which would provide life
support for a while and give time for prebreathing procedures, and then
a spacesuit-dependent bailout system.

While that's feasible, my gut feeling is that you're still better off with
a non-spacesuit lifeboat. And it does not strike me as substantially
harder to do, not when you deal with all the details.

It's also possible to design an emergency escape suit *that doesn't
require prebreathing*. Get in it, seal it, and pop out the airlock.
Prebreathe while dropping the pressure down to a level where you can
move the suit, complete the remainder of the escape sequence.

D.
--
Touch-twice life. Eat. Drink. Laugh.

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL

Derek Lyons wrote:
It's also possible to design an emergency escape suit *that doesn't
require prebreathing*. Get in it, seal it, and pop out the airlock.
Prebreathe while dropping the pressure down to a level where you can
move the suit, complete the remainder of the escape sequence.

Thing is that for an escape pod, you do not need mobility. You're not going to
be using some fancy screwdriver to connect cables and pipes and install
antennas. You just want to fire a deorbit engine and fall down. Once back in
atmosphere, you'd regain mobility as atmospheric pressure increases.

An escape pod is more likely to be some pressurized shell. A de-orbit engine
on a space suit might burn some of your extremities.

In article ,
Derek Lyons wrote:
It's also possible to design an emergency escape suit *that doesn't
require prebreathing*. Get in it, seal it, and pop out the airlock.
Prebreathe while dropping the pressure down to a level where you can
move the suit, complete the remainder of the escape sequence.

Unfortunately, starting from the station's normal 14.7psi atmosphere, suit
prebreathing even on an emergency basis takes about four hours, which is
kind of a long time to just float in the suit. (Preplanned spacewalks use
less prebreathing time than that because those guys live in reduced
pressure, with increased oxygen content, for 12+ hours first.)

Guys without current spacewalk training are going to be essentially
immobilized until pressure is down to near-normal suit levels; there isn't
going to be any useful mobility during the transition. Guys *with*
current spacewalk training -- which puts a lot of emphasis on building up
hand and arm muscles in particular -- may have some limited mobility late
in the transition.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

In sci.space.policy Henry Spencer wrote:
In article ,
Phil Paisley wrote:
Do I hear a MOOSE coming over the horizon?
Seriously, isn't it about time someone gave some serious thought to an
ultra-minimal personal re-entry scheme?

Alas for the notion, that's not really what's called for. A lifeboat that
can carry at least two or three people is generally superior, not least
because it doesn't require donning a spacesuit on short notice (which is
all too likely to cause decompression sickness, aka the bends -- not only
painful but also deadly dangerous).

And putting on my heretic hat...
Does a minimal reentry scheme require a spacesuit?
If there is a hole in your reentry vehicle, you'r probably already dead.

In sci.space.policy Ian Stirling wrote:
In sci.space.policy Henry Spencer wrote:
In article ,
Phil Paisley wrote:
Do I hear a MOOSE coming over the horizon?
Seriously, isn't it about time someone gave some serious thought to an
ultra-minimal personal re-entry scheme?

Alas for the notion, that's not really what's called for. A lifeboat that
can carry at least two or three people is generally superior, not least
because it doesn't require donning a spacesuit on short notice (which is
all too likely to cause decompression sickness, aka the bends -- not only
painful but also deadly dangerous).

And putting on my heretic hat...
Does a minimal reentry scheme require a spacesuit?
If there is a hole in your reentry vehicle, you'r probably already dead.


IMHO it goes (or should go) like:
life support in the suit - need suit
life support in the capsule - don't need

are the halfways really all that useful?


--
Sander

+++ Out of cheese error +++