Re: Space funding (was Re: Hillary needs to quit)

On Wed, 09 Apr 2008 10:11:30 -0500, pv+usenet@[EMAIL PROTECTED]
 (PV) wrote:


>NASA disagrees, since they're sending out teams to aerospace junkyards
all
>over the planet, looking for J2 engine parts. They've lost a lot of the
>design plans needed to build them again,

That's just an urban myth. Rocketdyne still has theirs, for example.
And they didn't go to junkyards all over the planet, they went to
Rocketdyne's storage facilities. (This happened in the 1990s, when the
J-2 was dusted off for the X-33 program.)

>and also lost almost all of the
>institutional knowledge as to why they were built the way they were, and
>how individual parts were machined. It's the biggest loss of engineering
>knowledge of all time. That's NASA today.

Baloney. Both J-2 and F-1 have been proposed for re-start several
times since the end of Apollo. NASA has the plans, the problem is that
no one today builds (insert anything aerospace-related) they way they
were built in the 1960s, the last time J-2 and F-1 rolled off an
assembly line. So the plans are a good starting point, but a lot of
new work has to be done to build those engines with today's industrial
base.

>SSRBs SUCK. Period. They can't be throttled, they can't be shut down, and
>they can't be aborted without jettisoning them and blowing them up. To
the
>devil with them. 

Shuttle's SRB has failed once in 244 flights*. You'll be hard-pressed
to find any rocket (liquid or solid) with a better service record. 

*2 SRBs on 122 Space Shuttle flights to date. And the one failure was
because NASA management ignored the warning of SRB engineers not to
launch in freezing conditions.

>>mass fraction that is still the best in the space industry. The
>>Shuttle's computers still operate software that is orders of magnitude
>>more reliable than standard commercial software. There is still no
>
>On hardware that's 20 years out of date, and no, it's not all that
>reliable. 

No, you can't compare aerospace computer hardware with the latest
Alienware gaming machine. Computers that run airliners, bombers and
the Space Shuttle use much older, proven hardware, that is designed to
withstand radiation, temperature, and vibration levels that only haunt
the nightmares of desktop computers. And because they don't have to
run Windows or MacOS, they don't need to be screaming-fast Intel
chips. For aerospace computers, the Shuttle's are top-notch. 

>They've had a lot of time to find bugs, but early on computer
>problems were a common source of scrubs and countdown delays.

Not really. The first flight was aborted by a synchronization problem.
That was 27 years ago Saturday. The last on-board computer-caused
delay I can find was on STS-41D in 1984... a one-day delay because the
backup computer failed.

FYI... they replaced the computers in the '90s. Shuttle's PASS and BFS
software (two totally independent software products) have failure
rates that Windows and Mac could never dare hope to come close to.

>>other operational reusable thermal protection system... Shuttle's
>>tiles are in a league of their own.
>
>Not any more they're not. And they're so freaking fragile that you can
>damage one by throwing a piece of foam at them, or with a fingernail.
This
>is not smart.

It is so long as you don't let honkin' big pieces of debris hit them.
That's why the spec (which NASA management ignored) said "NO FOREIGN
DEBRIS PERMITTED FROM THE EXTERNAL TANK."

And the Columbia accident wasn't caused by tile damage. It was a wing
leading edge carbon panel, hit be debris moving at supersonic relative
speeds.

>>Especially since it is the vehicle responsible for 70% of the people
>>who have ever travelled into space and has done so with a failure
>>record statistically no worse than its chief rival, Russia's Soyuz.
>
>At many times the cost. *

That's debatable. The Shuttle is more expensive, to be sure. But the
"many times" requires lots of caveats. For example, it takes three
Soyuz flights to carry as many people as one Shuttle flight. But that
one Shuttle flight can also carry 20,000 lbs. of supplies for the
Space Station, the equivalent of about four of Russia's "Progress"
cargo ****ps. The one Shuttle flight might cost more than the six or
seven Russian launches, but it will be a close call.

Brian