Don't Desert Hubble

Explorer8939 wrote:

I have to say that I am surprised how lightly everyone is taking the
ISS safe haven concept for Shuttle. What if a Shuttle is stranded at
ISS, and something goes wrong with the next Progress that is required
to keep the 10 person crew going? Is the ISS safe haven truly 2 fault
tolerant?



Because, the 3 remaining shuttles are all going to be in
rotation and an accelarated launch would have the next shuttle
going up within a few weeks..

And, ATV and Progress gives 2 resupply vehicles possible.



Brett Buck wrote in message ...

Brian Gaff wrote:

Hmm, I have not seen anywhere any detailed, data supported reasons for the
cancellations yet. Lots of words, but no arguable reason for it.

so, what is the reason?

Seems perfectly simple and well-defined to me. No on-orbit repair
capability because it's too expensive, no ready rescue flight because
it's too expensive, so all shuttle flight go to ISS as a safe haven.

What's so hard to understand about that?

Brett

(Explorer8939) wrote in
om:

I have to say that I am surprised how lightly everyone is taking the
ISS safe haven concept for Shuttle. What if a Shuttle is stranded at
ISS, and something goes wrong with the next Progress that is required
to keep the 10 person crew going? Is the ISS safe haven truly 2 fault
tolerant?

I have to say that I am surprised how lightly everyone is taking the LM
lifeboat concept for Apollo. What if the Service Module suffers a massive
systems failure, and something goes wrong with the LM that is required to
land on the moon? Is Apollo truly 2 fault tolerant?

--
JRF

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"Jorge R. Frank" wrote:

(Explorer8939) wrote:

I have to say that I am surprised how lightly everyone is taking the
ISS safe haven concept for Shuttle. What if a Shuttle is stranded at
ISS, and something goes wrong with the next Progress that is required
to keep the 10 person crew going? Is the ISS safe haven truly 2 fault
tolerant?

I have to say that I am surprised how lightly everyone is taking the LM
lifeboat concept for Apollo. What if the Service Module suffers a massive
systems failure, and something goes wrong with the LM that is required to
land on the moon? Is Apollo truly 2 fault tolerant?

The Apollo CSM/LM last flew over 30 years ago. How is that system
relevant to today?

--
Scott M. Kozel Highway and Transportation History Websites
Virginia/Maryland/Washington, D.C. http://www.roadstothefuture.com
Philadelphia and Delaware Valley http://www.pennways.com

On Fri, 13 Feb 2004 23:28:10 GMT, Brett Buck
wrote:

What's so hard to understand about that?

The "no ready rescue flight because it's too expensive" part. It would
be inconvenient (to ISS) but not particularly expensive.

Pretty expensive for a mission that was going to end relatively soon
in any case.

I don't follow... we've already spent a small fortune on SM-4, and the
replacement equipment already exists. So SM-4 by itself doesn't
present a particularly great cost to NASA. The big costs will be the
RCC repair technology, and NASA has essentially said SM-4 isn't worth
that cost. That puts the ball in Congress' court: they either have to
tell NASA to waive the CAIB recommendation or cough up the funding for
the repairs.

The rescue Shuttle would simply be the next scheduled Shuttle launch,
with some preparation to allow quick offloading of the ISS hardware
and loading of Shuttle/Shuttle rendezvous software. NASA holds the
SM-4 Shuttle until the ISS Shuttle is on the other pad a week or two
away from launch.

This is a scheduling inconvenience to be sure, but the history of the
Shuttle is replete with scheduling problems. What's one more?

Brian

"Scott M. Kozel" wrote in
:

"Jorge R. Frank" wrote:

(Explorer8939) wrote:

I have to say that I am surprised how lightly everyone is taking
the ISS safe haven concept for Shuttle. What if a Shuttle is
stranded at ISS, and something goes wrong with the next Progress
that is required to keep the 10 person crew going? Is the ISS safe
haven truly 2 fault tolerant?

I have to say that I am surprised how lightly everyone is taking the
LM lifeboat concept for Apollo. What if the Service Module suffers a
massive systems failure, and something goes wrong with the LM that is
required to land on the moon? Is Apollo truly 2 fault tolerant?

The Apollo CSM/LM last flew over 30 years ago. How is that system
relevant to today?

Because no manned spacecraft, past or present, is fully two fault tolerant.
Oh sure, they may be two fault tolerant in some systems, but not in all.
It's simply impractical. I believe no manned spacecraft will be *fully* two
fault tolerant in my lifetime. If Explorer8939 wishes to see a fully two
fault tolerant spacecraft, I suggest he take some sleeping pills, lie down,
and dream about them. That's the only place he'll see them in *his*
lifetime, either.

--
JRF

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check "Organization" (I am not assimilated) and
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Scott M. Kozel wrote:
The Apollo CSM/LM last flew over 30 years ago. How is that system
relevant to today?

No currently flying system is going to evolve into the future
US manned spaceflight system. As such, the age of anything
is irrelevant to the discussion.

Any feature from any past vehicle which appears to support
the new mission requirements is valid for consideration.
As are unflown but previously or newly proposed features.


-george william herbert

Brian Thorn wrote:

On Fri, 13 Feb 2004 23:28:10 GMT, Brett Buck
wrote:


What's so hard to understand about that?



The "no ready rescue flight because it's too expensive" part. It would
be inconvenient (to ISS) but not particularly expensive.


Pretty expensive for a mission that was going to end relatively soon
in any case.


I don't follow... we've already spent a small fortune on SM-4, and the
replacement equipment already exists. So SM-4 by itself doesn't
present a particularly great cost to NASA. The big costs will be the
RCC repair technology, and NASA has essentially said SM-4 isn't worth
that cost. That puts the ball in Congress' court: they either have to
tell NASA to waive the CAIB recommendation or cough up the funding for
the repairs.



The ET tanks alone costs more than the replacement equipment
for Hubble. Throw in all the associated non-recoverable launch
costs and an additional 2-3 months of Shuttle workforce and their
associated salaries.. If they don't fly SM-4, they can close
shop on the entire Shuttle infrastructure 2-3 months earlier than
otherwise. You are seriously looking at a mission that represents
potentially billions of dollars when you look at it as extending
the life of a program beyond a certain date. If they can close shop
on Dec 31 2009 without flying SM-4, but Mar 31 2010 with SM-4, what
are the associated costs of SM-4? It's about 1 billion dollars.

The last sentence you stated is the important one. This is a
political,not technical decision and NASA is putting it back onto
Congress to be *consistant*. NASA just got crucified for not following
basic safety requirements and now they are getting flamed for
not waiving those requirements when something "important" comes
along.

The rescue Shuttle would simply be the next scheduled Shuttle launch,
with some preparation to allow quick offloading of the ISS hardware
and loading of Shuttle/Shuttle rendezvous software. NASA holds the
SM-4 Shuttle until the ISS Shuttle is on the other pad a week or two
away from launch.

This is a scheduling inconvenience to be sure, but the history of the
Shuttle is replete with scheduling problems. What's one more?


The drop-dead date for Shuttle is 2010. They don't really have
any room for slippage.

There is no question that the NASA of today is less risk tolerant than
the NASA of the Apollo era.



"Jorge R. Frank" wrote in message ...
(Explorer8939) wrote in
om:

I have to say that I am surprised how lightly everyone is taking the
ISS safe haven concept for Shuttle. What if a Shuttle is stranded at
ISS, and something goes wrong with the next Progress that is required
to keep the 10 person crew going? Is the ISS safe haven truly 2 fault
tolerant?

I have to say that I am surprised how lightly everyone is taking the LM
lifeboat concept for Apollo. What if the Service Module suffers a massive
systems failure, and something goes wrong with the LM that is required to
land on the moon? Is Apollo truly 2 fault tolerant?

(Explorer8939) wrote in
m:

There is no question that the NASA of today is less risk tolerant than
the NASA of the Apollo era.

As is the rest of the country. A disease we will have to get over if we are
ever to go beyond LEO again.

--
JRF

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Charles Buckley wrote in
:

The ET tanks alone costs more than the replacement equipment
for Hubble.

Hmm? I'd sure like to see some sources for that. I've seen quotes of $200
million for the instruments alone on SM-4, let alone the gyros. That's at
least three ETs right there. And most of that $200 million has *already*
been spent.

The last sentence you stated is the important one. This is a
political,not technical decision and NASA is putting it back onto
Congress to be *consistant*.

You might want to tell O'Keefe that. He's certainly painting this as a
technical (specifically, crew safety) decision. Congress has every right to
override a political decision, but they would be understandably reluctant
to override a technical decision.

NASA just got crucified for not following
basic safety requirements and now they are getting flamed for
not waiving those requirements when something "important" comes
along.

No waiving of requirements is necessary. The CAIB certainly had no
intention of painting NASA into a corner such that they couldn't service
HST. Dr. Osheroff has already spoken up on that particular issue.

(Hint: Read chapter 10 of the CAIB report. There is *no* requirement for
ISS safe haven, nor a rescue shuttle for non-ISS missions.)

The drop-dead date for Shuttle is 2010. They don't really have
any room for slippage.

They have about 18 months, actually, based on the last manifest published
before the new space policy was announced.
--
JRF

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