launch/no lauch decision with crew?

From Jorge Frank:

And I've stated before that the biggest downfall of MEDS lies in its
dollar-for-dollar lack of benefit! If your opinion is that MEDS was a
*cost effective* way to make the shuttle more safe to fly

No, my opinion is that MEDS provides a substantial safety benefit while
also eliminating obsolescence issues with the former cockpit. I fully
recognize that shuttle upgrades are not *solely* prioritized by safety
issues - nor *should* they be. An obsolescence issue, neglected long
enough, can be just as serious as a safety issue. And relative to the
airlines and the military, NASA had already neglected the obsolescence of
the shuttle cockpit for too long.

My opinion is that the original cockpit could have adequately flown
out the life of the shuttle program. I'm not aware of any critical
safety or obsolescence issues. (As stated long ago, $200 million can
buy a LOT of steam gauges.)

I know of more than one NASA engineer who works with MEDS and sees it
as a waste of money. I know of more than one *pilot* who works at
NASA and sees MEDS as a waste of money.

I've been poking through a bunch of documents and found this opinion
voiced by the Aerospace Safety Advisory Panel:

. com
(http://tinyurl.com/2r7zo)


~ CT

In article , EAC wrote:
"Kent Betts" wrote in message ...
Giving the crew the final say puts the authority in the hands of the ones
with the most immediate interest, the most to lose, however you want to say
it.

The problem is that... humans have a built-in instict on NOT to ride
in any rocket, if one gives to the crew the go or no go decision,
chances are one of them probably will want a no go.

Humans have a natural instinct to do interesting things; the more
life-threatening sports are alive and well, and you'd be ahrd pressed to
find a more worryingly motivated collection than your average STS crew.

But I'm sure that if one of the crew suddenly freaked out before the
launch, they probably will replace it, that's why they got one of
those backup crews.

They do, in fact, not have backup crews; not as such, at least,
certainly not in the form they had in the Apollo era (where you had,
essentially, a 'shadow crew'). Key specialists may be explicitly backed
up, and I believe ISS expeditions have named backups, but the average
Shuttle crews aren't.

Shuttle crew-members have been pulled before, through illness,
reassignment or the like; this generally doesn't happen at the last
minute. In fact, I can't think offhand of a case of someone being pulled
in the days immediately preceding launch, and I'm fairly sure that
no-one has ever 'refused to go' on the pad, as it were - some may have
done at earlier stages, before assignment, but even that unwillingness
to fly would get you a ticket out pretty sharpish.

Come to think of it, if the Challenger crew had been advised that the SRBs
were 15 deg colder than previous experience, that o-ring erosion was
corelated to temperature, would they have launched?

The problem is that, was it really the o-ring erosion that caused the
Challenger explosion? The same also goes for the foam and the
Columbian.

Um, yes. O-ring erosion leads to O-ring burnthrough leads to mean nasty
ugly stuff. You can see it on the pictures if you spend enough time
looking; Feynman gives an excellently simple explanation if the
Commission report is a bit daunting. Very hard to come up with a
plausible alternate failure mode that explains what was observed. There
are, AIUI, details which are not very well understood about what
happened afterwards, and there are other factors which might have made a
launch with nominal SRBs problematic anyway [1], but the SRBs were what
caused "the Challenger accident".

Columbia & the foam is a little more tenuous - the actual breakup wasn't
observed as Challenger was, for various reasons - but the explanation is
entirely consistent with the evidence and later simulations, and any
other plausible failure mode doesn't quite correlate. It's theoretically
possible that some entirely unknown on-orbit problem damaged the RCC
without anyone noticing, and that the foam coincidentally bounced off
the same area earlier, but this is really quite implausible - to say the
least.

[1] Similar to Apollo 13 - A13 had a quite shaky flight before the
famous accident happened, with the Saturn V experiencing major problems,
though not enough to cause an abort or jepoardise the mission. But,
still, the closest an Apollo came to failing because of the booster...
it just got overshadowed by the other problems.

--
-Andrew Gray

Andrew Gray wrote:
The problem is that... humans have a built-in instict on NOT to ride
in any rocket, if one gives to the crew the go or no go decision,
chances are one of them probably will want a no go.

Humans have a natural instinct to do interesting things;

No, they don't. It's been popular to for the space and SF communities
to *claim* so over the last forty years, but the data does not back
them up.

the more life-threatening sports are alive and well,

Among a minority. (I'm not entirely certain what it says about our
society that people are willing to risk their lives for
entertainment.)

Now, as ever, the bulk of the population is interested in maintaining
the status quo or at best improving their own lot somewhat. Those
willing to take serious and significant risks are a minority.

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

"Kent Betts" wrote:
Giving the crew the final say puts the authority in the hands of the ones
with the most immediate interest, the most to lose, however you want to say
it.

It also puts the authority in the hands of the ones with the least
information and the least experience in interpreting it. Compare the
amount of information routinely displayed in the LCC/MOCR, and number
of specialists required to interpret it. How can the astronauts make
the decision with a fraction of the information and a fraction of the
practical experience?

Come to think of it, if the Challenger crew had been advised that the SRBs
were 15 deg colder than previous experience, that o-ring erosion was
corelated to temperature, would they have launched?

First that requires that the erosion was known to clearly correlated
to temperature. It wasn't. At the time of the accident, it was
suspected that the erosion was in fact related to temperature, but the
exact relationship and mechanism was unknown.

We have already seen that deciding who gets what information is just as
important as who makes the decision to launch.

Or how about:
Controller: "We don't know how to say this. Your GX-5 unit is really
flakey. We are 99% certain that entry will not be survivable."

Astronaut: "Oh yeah, that. We already took care of it. There was a bad pin
in the connector and Leroy straightened it and its ok."

....And not being a experienced technician, Leroy failed to properly
power down the GX-5 unit causing a brief temperature excursion inside
when the cooling was shut down before the power was. As a result the
performance characteristics changed such that it was stable in the
short term, but not in the long... The brief test showed that it was
clear of the flakiness, but after six hours of running, it failed
twelve minutes after entry interface.

Don't laugh. These things happen.

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

(Stuf4) wrote in
om:

From Jorge Frank:

And I've stated before that the biggest downfall of MEDS lies in
its dollar-for-dollar lack of benefit! If your opinion is that
MEDS was a *cost effective* way to make the shuttle more safe to
fly

No, my opinion is that MEDS provides a substantial safety benefit
while also eliminating obsolescence issues with the former cockpit.
I fully recognize that shuttle upgrades are not *solely*
prioritized by safety issues - nor *should* they be. An
obsolescence issue, neglected long enough, can be just as serious
as a safety issue. And relative to the airlines and the military,
NASA had already neglected the obsolescence of the shuttle cockpit
for too long.

My opinion is that the original cockpit could have adequately flown
out the life of the shuttle program. I'm not aware of any critical
safety or obsolescence issues. (As stated long ago, $200 million can
buy a LOT of steam gauges.)

I know of more than one NASA engineer who works with MEDS and
sees it as a waste of money. I know of more than one *pilot* who
works at NASA and sees MEDS as a waste of money.

I've been poking through a bunch of documents and found this opinion
voiced by the Aerospace Safety Advisory Panel:

. com
(http://tinyurl.com/2r7zo)

To save some trouble, here's what the link above points to:

Aerospace Safety Advisory Panel, Annual Report March 1994 (p24):

Ref: Finding #11
....
The cost of MEDS has been variously justified on the basis of safety
or as a remedy to the obsolescence of the existing instruments. In
general, neither existing safety problems nor obsolescence can fully
justify the cost of the retrofit, although MEDS should obviate any
current obsolescence issues.

My opinion of ASAP's opinion:

1) The way this is worded, it is unclear whether safety and obsolescence
issues were considered separately or collectively. Either alone may not
have been enough to justify the upgrade, but considering both together may
have made a difference.

2) Obsolescence issues grow with time when not addressed. A finding that a
particular obsolescence issue does not warrant an upgrade in 1994 becomes
less relevant years later.

3) The ASAP in 1994 was no more immune than NASA to the "not invented here"
attitude toward CRM/MMI issues unearthed by the airlines and military, so
it would not be surprising at all to me if they undervalued an MMI upgrade
like MEDS.

4) I have never claimed that MEDS should have been at the top of the
upgrade list, only that it was a worthy upgrade in a list of many other
worthy upgrades, and in any program with as few flights as the shuttle (at
least relative to aviation flight-test programs), prioritizing upgrades is
going to be an inexact science, at best.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

(Stuf4) wrote in
om:

From Jorge Frank:

You had a funny way of stating that, both in this thread and the
original thread six months ago. You stated that the MEDS upgrade "led
to death of Columbia crew." The only way that statement could be true
is if MEDS was chosen at the expense of another upgrade that could
have saved the crew. It was not.

"MEDS led to death" is not the same as "MEDS caused the death". Had I
stated a causal relationship, then I would agree with your criticism.

Most reasonable people interpret "A led to B" as a causal link between A
and B. They may not be identically the same, but the distinction is
trivial.

Even saying that it *possibly* would have saved Columbia is wrong.

I'm surprised at the level of certainty you have been expressing
here, Jorge.

An insightful observation, I'll grant you. I could not have expressed
this level of certainty six months ago when you first brought this
subject up. Hence my non-participation in the original thread. It
would not have been a productive use of my time. I've learned much
since then, about the aerothermal evidence from STS-107, the
limitations of the WLE MMOD upgrade, and how the now-resurrected
upgrade fits into the overall scheme of RCC hardening/repair. I have
as much certainty in my statement as the CAIB had in saying, "the
foam did it."

Now that's a level of certainty that I might agree to.

Then one of us is vastly misjudging the CAIB's level of certainty behind
the statement, "the foam did it." I meant it as absolute certainty.

We are agreed that the RCC failure was catastrophic. There's plenty
of evidence pointing to that. Our point of disagreement is regarding
the possibility that the failure threshold was only marginally
crossed.

Load a bridge just up to its ultimate failure point. Then toss a
chunk of foam on it. Cables snap. Girders twist. Clearly a
catastrophic failure. But the threshold was only crossed by adding
the foam. It's possible that wrapping those girders with Nextel might
have enabled the bridge to withstand the foam impact.

Your analogy is flawed. To make it more analogous to the proposed pre-107
WLE MMOD upgrade, you'd be putting the Nextel not around the girders, but
protecting the area underneath the bridge in case it collapsed.

...but all engineering analyses have limited precision,
particularly when key variables are unknown. Therefore I am not so
quick to eliminate the possibility (however slim that possibility
may be) that the foam impact may have been just one degree, one
deg/s, or one knot away from being on the other side of that RCC
integrity threshold. I cannot say with your certainty that the WLE
MMOD would not have made any difference.

I believe you are missing the point. It does not matter how close the
impact was to the threshold of *RCC* integrity, because the proposed
WLE MMOD upgrade would not have protected the RCC itself at all. It
was designed to protect the underlying wing spar from a 0.25 inch
hole in the RCC. So it would not have affected the size of the
resulting hole, just the rate at which the plasma from the hole
burned through the wing spar. But the heat flux from the hole in
Columbia would have been on the order of 600 to 1600 times what the
Nextel fabric was designed to take. It would not have delayed the
plasma breach in the wing enough to make any kind of difference in
the outcome. Perhaps the crew would have come to rest in Fort Polk
instead of Hemphill, but that's about it.

This argument was made early on (in much less detail than you are
providing).

My response then and now is that I do not know all the details of the
upgrade design. I would need more info before concluding that nothing
about the upgrade would have improved foam impact resistance.

It would have been nice if you'd done that research yourself before
starting your previous inflammatory thread.

If you can point me toward a source document, I would be extremely
interested in digging into it.

None of the source documents are available publicly, as far as I know. My
sources are presentations made to the VECB and ORTFWG. While not source
documents, strictly speaking, they do outline the scope of the proposed
upgrades. The WLE MMOD upgrade makes no mention of RCC hardening, while
other, (and post-107) proposed upgrades make explicit mention of RCC
hardening. This omission, combined with the vast differences in cost and
schedule between the WLE MMOD upgrade and the proposed RCC hardening
upgrades, strongly leads me to the conclusion that the WLE MMOD was not and
is not intended to harden the RCC.

We are agreed on the primary point made in that original thread. And
that was offered in criticism of the CAIB conclusion that shuttle was
not given enough money.

No amount of money could have prevented the 107 accident without the
recognition that foam debris could damage RCC. Without that recognition,
*all* shuttle upgrades would have been - and were - directed to areas other
than those that doomed 107.

Whether or not any upgrade could have prevented -107's RCC breach is
tangential to that point.

I don't agree with that at all. Since none of the other upgrades proposed
prior to 107 could have prevented - or even mitigated - the accident, the
only effect of NASA not choosing MEDS would have been to change your
scapegoat once the accident occurred. You would have started a thread
titled "AHMS led to deaths of Columbia crew" or "EAPU led to deaths of
Columbia crew." Or whatever upgrade NASA picked in substitute. It was a
bogus argument then and it's still bogus now.

Had NASA divided their limited cash pot by axing MEDS and funding
stronger WLEs and then -107 gets destroyed anyway? I don't see
myself as calling that a fatal funding decision. I would see
myself saying that the threat was addressed, but addressed
inadequately.

More like the *wrong* threat was addressed. Foam impacts are
fundamentally different from MMOD impacts, both in the amount of
kinetic energy and the area over which it's applied. That makes a
*lot* of difference in the resulting damage.

When the overwhelming majority of impacts on the RCC were Stage I foam
strikes, I find it difficult to imagine that a WLE upgrade design
would have dealt only with the MMOD threat.

Why do you think the it was called the "WLE MMOD upgrade" in the first
place? Pre-107, there was little to no awareness at NASA that foam debris
could damage RCC. Next to ascent systems/propulsion failures, MMOD impact
was regarded as the most serious threat to an orbiter. And *no* amount of
RCC hardening would have been sufficient to protect against MMOD impacts -
the proposed WLE MMOD upgrade essentially makes the WLE into a Whipple
shield, with the RCC as the "sacrificial" outer layer. The wing spar would
have gotten all the protection.
--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

On or about 23 Mar 2004 03:18:24 GMT, Jorge R. Frank
made the sensational claim that:
Why do you think the it was called the "WLE MMOD upgrade" in the first
place? Pre-107, there was little to no awareness at NASA that foam debris
could damage RCC.

If it can dent an SRB...Seriously, "how tough is RCC?" is a question I always
wanted to ask someone knowledgable. I'd have thought someone would have
wondered what that chunk of foam on 112 would have done to the *orbiter*.
That's the awful part of it all, how glaringly obvious it should have been.
--
This is a siggy | To E-mail, do note | Just because something
It's properly formatted | who you mean to reply-to | is possible, doesn't
No person, none, care | and it will reach me | mean it can happen

In message , Derek Lyons
writes
Andrew Gray wrote:
The problem is that... humans have a built-in instict on NOT to ride
in any rocket, if one gives to the crew the go or no go decision,
chances are one of them probably will want a no go.

Humans have a natural instinct to do interesting things;

No, they don't. It's been popular to for the space and SF communities
to *claim* so over the last forty years, but the data does not back
them up.

the more life-threatening sports are alive and well,

Among a minority. (I'm not entirely certain what it says about our
society that people are willing to risk their lives for
entertainment.)

That society has a necessary minority of people prepared go to the edge
and beyond? The problem comes when those people expect other people to
risk _their_ lives and _my_ money to rescue them.
--
Save the Hubble Space Telescope!
Remove spam and invalid from address to reply.

Jonathan Silverlight
wrote:

In message , Derek Lyons

Among a minority. (I'm not entirely certain what it says about our
society that people are willing to risk their lives for
entertainment.)

That society has a necessary minority of people prepared go to the edge
and beyond?

If you accept that those who take part in life threatening individual
sports are a congruent set with societies necessary minority of
explorers, I'd agree with you.

However, I don't accept such an implied stipulation as the risk takers
in question tend to risk their lives repeatedly in the same manner as
opposed to doing something adventurous. There is a qualitative
difference between the type of personality who bungee jumps for
thrills, and the type of personality who enjoys walking into the
Amazon rain forest to survive for a week starting with nothing but a
pocketknife. One is an adrenaline addict, one is a seeker of
challenges.

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

From Jorge Frank:

My opinion of ASAP's opinion:

1) The way this is worded, it is unclear whether safety and obsolescence
issues were considered separately or collectively. Either alone may not
have been enough to justify the upgrade, but considering both together may
have made a difference.

2) Obsolescence issues grow with time when not addressed. A finding that a
particular obsolescence issue does not warrant an upgrade in 1994 becomes
less relevant years later.

3) The ASAP in 1994 was no more immune than NASA to the "not invented here"
attitude toward CRM/MMI issues unearthed by the airlines and military, so
it would not be surprising at all to me if they undervalued an MMI upgrade
like MEDS.

4) I have never claimed that MEDS should have been at the top of the
upgrade list, only that it was a worthy upgrade in a list of many other
worthy upgrades, and in any program with as few flights as the shuttle (at
least relative to aviation flight-test programs), prioritizing upgrades is
going to be an inexact science, at best.

Early on, I shared my agreement that MEDS has been an excellent
improvement for the shuttle. What is at issue is not the value of
MEDS, but rather its opportunity cost.

I would also agree that upgrade prioritization is an inexact science
at best. So do we uphold the MEDS funding as an example of 'best'
prioritization? Or do we identify it as a clear mistake. Seven
astronauts are gone with the loss of Columbia. I did not read any
CAIB statement about prioritization of upgrades. I did see them state
that NASA wasn't given enough money.

Apparently they think that MEDS was money well spent.

....or perhaps they wanted to leave the upgrade prioritization as an
"unturned stone". When they publish a conclusion that the mishap
occurred due to damage to the wing leading edge, I am of the opinion
that it is imperative to at least mention planned upgrades to that
wing leading edge. Even if they don't want to delve into the story of
*why* it got cancelled.


~ CT