Never mind the shuttle crash, the real threat is the CAIB report

My oppinion is that the shuttle is reliable as far as launch vehicles are
concerned. Two failures out of 100 missions is pretty good. It is also a
terrible idea as far as basic engineering is concerned.

It is bad for the following reasons:

1. Does not have adequate crew escape systems
2. Does not have adequate redundancy.
3. Launches a lot of extra mass (the orbiter) unnecesserily

The best way to launch people to orbit so far has been the apollo program's
capsule type launch and return.

There is no point wasting fuel to launch a heavy orbiter just to have it return
to the earth later.

NASA is carrying a lot of dead weight too, kind of like the shuttle. Many
academic type people who produce no more than paperwork, resulting in huge
costs and not enough engineering. The same is true for the rocket community.
There are many people riding the wagon of SSTO or RLV projects, writing papers,
charging salaries to projects that they don't contribute to.

We need a low tech heavy launch system for large payloads (energia comes to
mind) and we need a light weight crew launch system with adequate safeguards
(LET). There is no point wasting fuel and money on having the shuttle go up and
down.

Manned space exploration is essential for our survival. We need a moon base, we
need to go to Mars and to the asteroids ASAP.

Zoltan Szakaly
vtol.net

For Hubble, there were *three* null correctors, and two out of three said
that the mirror was shaped incorrectly (although unfortunately the most
precise of the three was the one that said it was okay). Management
*explicitly* decided that this strange discrepancy would not be
investigated, because the project was already over budget and behind
schedule.

Henry, was this by NASA management or by Perkin-Elmer? If PE reported
all to NASA and they decided that way I see no much reason to blame
PE. Btw, is "Hubble Wars" the best report on this?


## CrossPoint v3.12d R ##

In article ,
Jan C. =?iso-8859-1?Q?Vorbr=FCggen?= wrote:
Several of Galileo's problems can be traced back to management. (I mean,
a star tracker that's only tested in two or three orientations???

Could you provide a quick summary of what problems/constraints that caused?

(Background: Galileo is an odd design, half of it spinning slowly to
provide gyroscopic stability and a full-sky view for things that want it,
and the other half holding a fixed orientation to support things like the
camera. The star tracker -- it's more of a star scanner actually -- is on
the spinning half, so it sweeps over a ring of sky.)

The underlying problem, if I recall the paper correctly, is that the star
tracker uses an unusual approach, and a little too much of its signal
processing is hard-wired, and the very limited testing did not uncover
some design weaknesses. Too much information is lost, and going from the
pulse train it produces to a solid attitude determination is difficult.

For some orientations of the spin axis, in fact, it's impossible... so
there are directions Galileo cannot point for any length of time (it can
hold any attitude briefly using gyros, but needs a star lock for long-term
stability). For some substantial fraction of all attitudes, it needs to
be told to settle for a fairly loose fit to the star map. And in general,
the preparation of star maps for it is tricky and labor-intensive.

In short, not a mission killer, but it ran up the cost and aggravation of
Galileo operations noticeably.
--
MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer
first ground-station pass 1651, all nominal! |

In article ,
wrote:
For Hubble, there were *three* null correctors, and two out of three said
that the mirror was shaped incorrectly (although unfortunately the most
precise of the three was the one that said it was okay). Management
*explicitly* decided that this strange discrepancy would not be
investigated, because the project was already over budget and behind
schedule.

Henry, was this by NASA management or by Perkin-Elmer?

If memory serves, this was a P-E decision. NASA supervision of the
details of the optics work was limited, because this was basically a
spysat shop, heavily encumbered by security restrictions that NASA was
ill-equipped to deal with.

...Btw, is "Hubble Wars" the best report on this?

I'm told that people who were there have a tendency to say "now wait a
minute, that's not right..." every few pages. Read it for background, but
it's not an entirely trustworthy account.
--
MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer
first ground-station pass 1651, all nominal! |

(Henry Spencer) wrote in message ...

If memory serves, this was a P-E decision. NASA supervision of the
details of the optics work was limited, because this was basically a
spysat shop, heavily encumbered by security restrictions that NASA was
ill-equipped to deal with.

Does this mean that there might have been a KH-11 that also had the
faulty mirrors? Or was the confusion over the null corrector's a
one-shot deal?

Chris Manteuffel

In article ,
Chris Manteuffel wrote:
If memory serves, this was a P-E decision. NASA supervision of the
details of the optics work was limited, because this was basically a
spysat shop, heavily encumbered by security restrictions...

Does this mean that there might have been a KH-11 that also had the
faulty mirrors? Or was the confusion over the null corrector's a
one-shot deal?

It was a one-shot. The *shop* did other work, but the Hubble mirror
itself was a special project, rather than just another mirror off the
production line.
--
MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer
first ground-station pass 1651, all nominal! |