$64 Billion and seventeen years to land on the moon. What's wrong with this picture?

Derek Lyons wrote:

For any decent sized production run, the variances won't be
maintenance issues or major operational issues if your organization is
even marginally competent. (This can be seen even in the Shuttle if
you divide them into the four groups they fall naturally into;
Group-1; Columbia, Group-2; Challenger, Group-3; Everybody else.)

"Bob, you've got ol' number 97 next flight. She's a little flightly
at flare, always been that way."


It's funny you mention this, as I was re-reading parts of Milt
Thompson's "At the Edge of Space", and he was commenting on how all the
early production run Lockheed F-104s had noticeably different flying
characteristics.

Pat

In article , says...
In article ,
William R. Thompson wrote:
...The VAB
is getting old, and I don't think it was meant to survive
forever [...]

The first is that NASA has a general pattern of skimping on maintenance,
at KSC and elsewhere, and the VAB probably needs work. [...]
NASA has generally tried to get away with about 1%,
which is not enough.)

Given that the VAB is a one-of-a-kind creation, it probably needs more,
not less, than the rule-of-thumb. I just had a vision of a Shuttle
reaching the same end as the Buran...
--
Kevin Willoughby lid

Imagine that, a FROG ON-OFF switch, hardly the work
for test pilots. -- Mike Collins

(Mark) wrote in message om...
(ed kyle) wrote in message . com...
Vehicle Successes/Tries Realzd Pred Consc. Last Dates
Rate Rate* Succes Fail

I'm not quite sure what that's meant to prove, since there are no
reusable vehicles on that list, and a 60/60 success rate is nowhere
near enough flights to really gauge reliability to 1% accuracy.


It is enough to provide a 98% first-order Bayesian estimate
of mean predicted probability of success for next launch
attempt.


Note that the STS is not reusable, even though the shuttle orbiter is:
and both Challenger and Columbia were lost due to failures in the
_expendable_ parts of the STS, not the reusable orbiters.


Challenger was lost due the failure of a reusable SRB*.
Columbia was lost when the reusable orbiter thermal protection
system (the fragility of which NASA did not understand even
after flying the stuff and getting it back for detailed analysis
111 times) failed.

*According to the STS-51L Rogers Commission Report, Only two of
the 22 components in the 51-L solid rocket booster (SRB) stack
were new. The remaining 20 components had been used a combined
total of 29 times previously, in ground tests and in flight.
The new components, the right forward center tang and the left
forward dome, were not involved in the failure.

- Ed Kyle

(Derek Lyons) wrote:
Pat Flannery wrote:
In a word, cost.
It's a lot more expensive to come up with a new or growth version of a
reusable than a expendable;

That depends greatly on how big the difference between the new/growth
version of either type is and the original version. It might be cheap
if all they do is swap out a few more-or-less plug compatible
components, it might be very expensive if they re-engine it and have
to replace the thrust frame. It's impossible to make blanket
statements like you do above.

(Or in short, once again you revert to "two legs bad, four legs
good".)


But Derek, don't you think that swapping out the APUs but not doing
anything about the tile maintenance makes for a STS-II that is still
going to be too expensive to operate and too fragile?

And the next high maintenance item is the SSME, and swapping in RL-68s
is likely to require significant airframe redesigns.

Why would we do STS-II if the improvements weren't enough to change
costs are reliability significantly?


and after looking at the economics of the STS and Buran it's going to be
a long time before anyone goes down that particular design path again.

Which is sad that people are blinded by headlines rather than making
decisions based on engineering and operational headlines.

(Or in short, once again you revert to "two legs bad, four legs
good".)


Or in short you accuse Pat of Dogma without offering any rational
alternative.

Show us the engineering that says "we've got a real valid reason for
doing wings on our next spacecraft".

/dps

(dave schneider) wrote:

snippage of arrant nonsense utterly lacking in connection to the
topic at hand.

Or in short you accuse Pat of Dogma without offering any rational
alternative.

In short, pointing out a bias does not require doing any such thing.

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

On Wed, 10 Mar 2004 16:03:23 -0600, Pat Flannery
wrote:

Derek Lyons wrote:

For any decent sized production run, the variances won't be
maintenance issues or major operational issues if your organization is
even marginally competent. (This can be seen even in the Shuttle if
you divide them into the four groups they fall naturally into;
Group-1; Columbia, Group-2; Challenger, Group-3; Everybody else.)

"Bob, you've got ol' number 97 next flight. She's a little flightly
at flare, always been that way."

It's funny you mention this, as I was re-reading parts of Milt
Thompson's "At the Edge of Space", and he was commenting on how all the
early production run Lockheed F-104s had noticeably different flying
characteristics.

The two F-4H test aircraft, built on the same production line using
the same fixtures, were sufficiently crooked that they spun
preferentially in different directions. I've forgotten the
measurements, but the difference was substantial.

Mary

--
Mary Shafer Retired aerospace research engineer

Kevin Willoughby wrote:

Given that the VAB is a one-of-a-kind creation, it probably needs more,
not less, than the rule-of-thumb. I just had a vision of a Shuttle
reaching the same end as the Buran...


I still snicker about that strange, and _very_ Russian accident.
"Comrade! The roof is structurally unsound! Repair it!"
"The repair materials have arrived! Where shall we place them?"
"Why, where the work is to be done, of course!"
"Place them on the roof!"
That's Russia in a nutshell.

Pat

(ed kyle) wrote in message . com...
It is enough to provide a 98% first-order Bayesian estimate
of mean predicted probability of success for next launch
attempt.

Agreed, but any viable reusable vehicle should be designed for a
success rate much higher than 98%.

Challenger was lost due the failure of a reusable SRB*.

SRBs are not reusable in any meaningful sense of the word. It's about
as sensible as claiming that SSMEs would be 'reusable' if you kept the
outside of the nozzle and replaced everything else for every flight.

Columbia was lost when the reusable orbiter thermal protection
system (the fragility of which NASA did not understand even
after flying the stuff and getting it back for detailed analysis
111 times) failed.

Nope. Columbia performed as it was designed to, it was the ET
insulation that failed.

Mark

"Mark" wrote in ...

SRBs are not reusable in any meaningful sense of the word.

Possibly around the level of Toner Cartridges which when
reused are often referred to as 'remanufactured'.

I would have thought there would be a decent cost analysis
_somewhere_ for the present SRB system vs. one where no
attempt is made to reuse them. But I couldn't find one.

dave schneider wrote:

(Or in short, once again you revert to "two legs bad, four legs
good".)




Or in short you accuse Pat of Dogma


It's starting to dawn on you that I might be just a _bit_ more than
human, isn't it? It will dawn on Derek about the time he wakes up
sitting on the lily pad with the taste of dead flies in his mouth....as
to how his old Navy pals are going to react to a former shipmate who
hops around the room making croaking noises at their next reunion is
anyone's guess, but I'll bet he'll have a fun time explaining it to
everyone after the switched souls return to their proper bodies. As to
how the frog explains to _its_ compatriots the fact that it now has
propellors tattooed on it's rear end is another matter entirely.


without offering any rational
alternative.


First thing I do when I get Absolute Power is repeal the "laws" of
physics, and indeed rationality itself....
Picture a world that works like an Escher painting- and going up a
simple flight of stairs may take the rest of their lives for those
foolish enough to attempt it, as they slowly transform from birds, to
fish, to birds, over and over again; where failing to get off the toilet
within 30 seconds of flushing it _really will_ give the thing living in
the sewer system time enough to swim up into the bowl and from there
leap into your anus...where it will lay its eggs; and where television
is tasteful, thoughtful, educational, and entertaining- all at the same
time; this last one won't be as easy as the first two, but if I play
around with how "time" works enough....

Show us the engineering that says "we've got a real valid reason for
doing wings on our next spacecraft".


And show _Me_ where it says that a former submariner _shouldn't_ have a
three foot long sticky tongue, webbed hands and feet, and a proclivity
to urinate when handled.


Ol' "Two legs good, six arms even better":
Shiva The Annoyer :-P