What's the most likely thing to cause another Challenger-like disaster?
James Anatidae
break-up on reentry, crashing on the runway, or maybe something else? Any
of you experts in here have an opinion?
(And, just for your information, I ask this out of simple curiosity and not
because I like seeing things blow up, so please don't flame me.)
--
"If it weren't for my horse, I wouldn't have spent that year in college."
- Girl in IHOP, relayed by Lewis Black
Wildwing's Storage Room
http://anatidae.homestead.com/frontdoor.html
Jorge R. Frank
news:b0tqan$o0c$2...@news3.infoave.net:
> The rockets blowing up (ala 51-L), meteorite hit, loss of cabin
> pressure, break-up on reentry, crashing on the runway, or maybe
> something else? Any of you experts in here have an opinion?
NASA computes the current probability of losing a shuttle at 1 in 250. Out
of that, the largest single risks are mechanical failure during ascent (1
in 500) and micrometeoroid/orbital debris strike (1 in 700), with all other
causes combined accounting for the remainder.
The next round of SSME upgrades (Block III) will likely reduce the risk of
ascent failure below that of micrometeoroids/orbital debris.
--
JRF
Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.
Downy
Henry Spencer
James Anatidae <pars...@citcom.net> wrote:
>The rockets blowing up (ala 51-L), meteorite hit, loss of cabin pressure,
>break-up on reentry, crashing on the runway, or maybe something else? Any
>of you experts in here have an opinion?
When OTA looked at this a few years after Challenger, if memory serves,
they concluded that probably the single likeliest way to lose an orbiter
was a landing accident. There have been three or four close calls. The
orbiter is not a very good aircraft -- its handling characteristics are
odd, its landing speed is so high that everything happens very quickly,
and there is no room for even the smallest mistake in handling or
misjudgement of weather.
--
Faster, better, cheaper requires leadership, | Henry Spencer
not just management. | he...@spsystems.net
Joe D.
burn-through was mentioned in the early 1970s, before the shuttle design was
even frozen. See http://history.nasa.gov/SP-4221/ch9.htm, page 420.
Despite Challenger, SRBs are mechanically simple compared to SSMEs, and can
be meticulously inspected, x-rayed, etc. Short of a serious QA problem, it's
hard to envision another SRB burn-through failure.
That said, the SRBs are definitely critical. For example, I think the
maximum left/right
ignition differential is 100 milliseconds -- any more and it will exceed the
ET structural limits. However NASA knows this so the SRB ignition
pyrotechnics are very reliable.
The SSMEs are complex and highly stressed. There's an engineering saying:
complexity breeds failure. However they're closely monitored and if
Challenger 51-F (SSME failed at 5:45, Abort to Orbit), a shutdown is
more likely than a catastrophic failure. The new SSMEs should further reduce
this problem.
However the Shuttle has relatively little reserve delta-V capacity. By
contrast the Saturn V could lose multiple engines on multiple stages, and
under some conditions use the excess TLI delta-V capacity to make orbit. It
could almost (but not quite) skip the entire second stage and use the SIVB
plus SPS to make orbit. If the fault detection logic on the new SSMEs is
overly aggressive and causes a premature shutdown, that could easily lead to
an intact abort (at the minimum), or a contingency abort (possibly a bail
out).
We tend to think in terms of single failures, which are easier to shield
against. However a sequence of failures could cause an orbiter loss. E.g.
an ET ullage leak or cabin pressure leak, leading to an RTLS or TLA abort,
which in turn enters a relatively untested flight control regime, that leads
to a thermal, flight control, or software problem.
STS-93 gives a few more hints of possible problem areas. An injector pin
struck the interior engine wall, rupturing 3 hydrogen coolant tubes,
resulting in slight overtemp and engine underperformance. On the same flight
two engine controllers on separate engines failed due to wiring problems.
The backup controllers took over.
Each time a problem is encountered, fixes are made and procedures changed to
avoid a recurrence. So although the above shows certain problem types that
under worse conditions could have caused an abort or orbiter loss, it seems
unlikely that these specific problems will happen again.
The bottom line is we don't really know. Ascent is the most high energy,
highly stressed phase, so a failure there is more likely. However an on
orbit micrometeoroid problem, or a reentry problem could happen.
Hopefully the shuttle will fly without further serious malfunction until it
is retired. Despite Challenger it has a pretty good record. Even the Saturn
V had problems (Apollo 13 pogo-induced SII inboard engine failure), although
it luckily eluded a catastrophic failure.
I wonder how likely is an intact abort vs a catastrophic failure? NASA has
elaborate procedures for various ascent aborts, but they mostly assume a
limited failure like a single SSME, or maybe two. Yet historically it seems
launch vehicles (including the Shuttle) either work pretty well, or fail
disastrously, with little in between.
-- Joe
Jorge R. Frank
> Obviously not someone that has seen the Crewmember Mortality Study...
Obviously. What does it say, specifically?
JF Mezei
>
> The rockets blowing up (ala 51-L), meteorite hit, loss of cabin pressure,
> break-up on reentry, crashing on the runway, or maybe something else? Any
> of you experts in here have an opinion?
crashing on runways wouldn't have the same media impact as the other ones.
Worse one would be something which strands the shuttle on orbit. (failure of
de-orbit engines, or failure of APUs neeed for re-entry). This would be a
"long" waiting period until they ran out of oxygen.
Lets say such a failure were to happen after a shuttle undocked from ISS (same
orbital plane). Could they conceptually use a soyuz with one person in it to
go and dock with shuttle to bring supplies and oxygen and perhaps bring back
3-4 people ?
(two in soyuz, 2-3 in orbital module)
Just how imcompatible is the ODS of the shuttle with a soyuz ? Could they get
some sort of mechanical hooking, even if no airtight seal ? They could vacuum
the airlock and the Soyuz orbital module and transfer the supplies from soyuz
to airlocks, close the doors, and then the shuttle would have access to
supplies without needing EVA.
JF Mezei
> > The next round of SSME upgrades (Block III) will likely reduce the risk of
> > ascent failure below that of micrometeoroids/orbital debris.
In terms of absolute disasters, are the SSMEs really the scary part ? Seems to
me that prior to liftoff, the computers check these things inside out and will
scrub the launch if they are not fully happy.
Aren't the SRBs the biggest risk of ascent catastrophy ?
If the SSMEs fail, is this truly as bad a day as if an SRB fails ?
James Anatidae
--
"If it weren't for my horse, I wouldn't have spent that year in college."
- Girl in IHOP, relayed by Lewis Black
Wildwing's Storage Room
http://anatidae.homestead.com/frontdoor.html
Jorge R. Frank <jrf...@ibm-pc.borg> wrote in message
news:Xns930E9B21...@204.52.135.10...
> "James Anatidae" <pars...@citcom.net> wrote in
> news:b0tqan$o0c$2...@news3.infoave.net:
>
> > The rockets blowing up (ala 51-L), meteorite hit, loss of cabin
> > pressure, break-up on reentry, crashing on the runway, or maybe
> > something else? Any of you experts in here have an opinion?
>
> NASA computes the current probability of losing a shuttle at 1 in 250.
That's really not very good. I certainly wouldn't get on a plane where the
chances were that it would crash after 250 flights.
Kent Betts
What sort of failure would preclude a return, and is there a practical
provision for a rescue rondezvous?
Is the re-entry phase a high-risk flight region? I mean, I figure the
chance of a wing falling off is pretty low, but if the thing got sideways it
would be bad news.
"Jorge R. Frank" <jrf...@ibm-pc.borg> wrote in message
news:Xns930E9B21...@204.52.135.10...
James Graves
>NASA computes the current probability of losing a shuttle at 1 in 250. Out
>of that, the largest single risks are mechanical failure during ascent (1
>in 500) and micrometeoroid/orbital debris strike (1 in 700), with all other
>causes combined accounting for the remainder.
>
>The next round of SSME upgrades (Block III) will likely reduce the risk of
>ascent failure below that of micrometeoroids/orbital debris.
I presume that losing a tile or two on the underside won't cause a
critical failure during re-entry. Would losing two or three adjacent
tiles be a problem?
James Graves
Joe D.
post-ignition, pre-liftoff "sanity check", nor opportunity for a pad abort.
They cannot be shut off once started. They must ignite within 100
milliseconds of each other, else will exceed the ET structural limits. OTOH
they're relatively simple devices relative to the SSME. They can be X-rayed
and meticulously inspected.
I recall STS-1 had many (dozens, maybe hundreds) of instrumentation
parameters on the SRBs. By 51-L, there were only three parameters measured
on the SRBs. The logic was you can't do anything about it if anything goes
wrong, so why measure it.
By contrast the SSMEs are very complex, highly stressed devices. The
combustion chamber pressure is several times the Saturn V F-1 engine, 3380
psi, vs the F-1's 763 psi. That's higher than a SCUBA tank. I am still in
awe of the SSME turbopumps. They have no lubricating oil (would freeze or
vaporize due to temps). One end is in cryogenic fluid, the other in fiery
temperatures. The hydrogen turbopump produces 75,000 horsepower, in the size
of an outboard motor.
Counterbalancing this, the SSMEs have many instrumentation parameters, and
have several seconds post-ignition and pre-liftoff for a go/no go sanity
check. Once they've run for several seconds, and hundreds of parameters have
been scanned many times, there's less likelihood of an in-flight failure.
Any significant SRB problem is generally catastrophic. However it's less
likely to happen. There are survivable abort options for all single SSME
failures. Probably most two SSME failures are potentially survivable, and
some triple SSME failures are survivable (although causing a ditching and
bailout). A triple SSME failure before SRB sep is probably catastrophic due
to overstressing orbiter/ET attach struts, although we don't really know.
The new block IIA SSME, which flew on STS-88, should be much more reliable.
It has lower chamber pressure, yet achieves the same specific impulse.
-- Joe D.
"JF Mezei" <jfmezei...@vl.videotron.ca> wrote in message
news:3E331D78...@vl.videotron.ca...
Storm Falcon
"Henry Spencer" <he...@spsystems.net> wrote in message
news:H9ALs...@spsystems.net...
> When OTA looked at this a few years after Challenger, if memory serves,
> they concluded that probably the single likeliest way to lose an orbiter
> was a landing accident. There have been three or four close calls.
Can you say what those close calls were? Or is information on this available
somewhere? I'm curious to know what happened.
Jorge R. Frank
> If the SSMEs fail, is this truly as bad a day as if an SRB fails ?
Depends on how they fail. If the main engine controllers spot something
out of limits and shut down the engine in time, it's survivable. But if a
turbopump ingests debris, throws a turbine blade, and starts flinging
shrapnel around the aft compartment, things get really ugly really fast.
Jorge R. Frank
news:v37dr81...@corp.supernews.com:
> Would the simultaneous loss of all three fuel cells disable the
> re-entry?
Yes.
> What sort of failure would preclude a return,
Plenty. Here's some I can think of, in addition to loss of 3 fuel cells:
Loss of all 3 APUs (even loss of 2 is iffy)
Loss of all 3 IMUs (the orbiter *might* get by on the RGAs, but it's still
a Bad Day), or the loss of the three flight-critical MDMs that allow the
computers to communicate with the IMUs.
Loss of both OMS engines plus two +X RCS jets
Loss of thermal protection system integrity
Loss of cabin pressure (if fast enough)
Lowering the landing gear while in orbit (can only be retracted on the
ground)
Payload bay doors fail to close (there's a contingency EVA procedure for
this)
ET umbilical doors fail to close (there's a contingency EVA procedure for
this, but unlikely to work)
Generic PASS software bug, plus any failure that takes out the BFS (there
are several)
There's plenty more, I'm sure.
> and is there a
> practical provision for a rescue rondezvous?
Not really. There was consideration of this back in the 1970s, when the
predicted shuttle flight rate was about one per week so there'd always be
one on the pad while the previous one was still in space.
> Is the re-entry phase a high-risk flight region? I mean, I figure the
> chance of a wing falling off is pretty low, but if the thing got
> sideways it would be bad news.
There's not a lot of room for error during entry, but for the most part,
the systems controlling the orbiter are highly redundant, and there are
flight rules requiring early mission termination when that redundancy is
lost.
Jorge R. Frank
> crashing on runways wouldn't have the same media impact as the other
> ones.
I think it would. The media impact of Challenger came from the fact that
thousands of people saw it live, and millions saw it on TV. A landing
accident would be similar, in that respect.
> Lets say such a failure were to happen after a shuttle undocked from
> ISS (same orbital plane). Could they conceptually use a soyuz with one
> person in it to go and dock with shuttle to bring supplies and oxygen
> and perhaps bring back 3-4 people ?
> (two in soyuz, 2-3 in orbital module)
Conceptually, perhaps, provided that 1) the Soyuz comes from ISS (fairly
non-credible that the Russians would happen to have one on the pad ready to
launch when the shuttle emergency occurred) 2) the emergency occurs before
the shuttle got far from ISS, and 3) the Soyuz has adequate lifetime left
for the dual rendezvous (a Soyuz has a free-flight lifetime of just 4.2
days when not attached to a station, and the initial ISS rendezvous uses up
2 days from that).
>From a practical standpoint, no.
> Just how imcompatible is the ODS of the shuttle with a soyuz ? Could
> they get some sort of mechanical hooking, even if no airtight seal ?
Very incompatible. Soyuz uses probe & drogue; the shuttle uses APAS. The
capture mechanisms are completely different, and the pressurized collars
are wildly different diameters.
Rodrigo Cunha
> In terms of absolute disasters, are the SSMEs really the scary part ? Seems to
> me that prior to liftoff, the computers check these things inside out and will
> scrub the launch if they are not fully happy.
Sure, and than 3 minutes into the flight your nice fully checked
vulcain-2 blows :-)
Another example is the recent soyuz launch failure: all 5 engines are
tested live on the pad. Still one of them blew itself into small bits 20
seconds later.
Engines generally won't blow right away, unless they are very badly built.
Jorge R. Frank
> Jorge R. Frank <jrf...@ibm-pc.borg> wrote in message
> news:Xns930E9B21...@204.52.135.10...
>> "James Anatidae" <pars...@citcom.net> wrote in
>> news:b0tqan$o0c$2...@news3.infoave.net:
>>
>> > The rockets blowing up (ala 51-L), meteorite hit, loss of cabin
>> > pressure, break-up on reentry, crashing on the runway, or maybe
>> > something else? Any of you experts in here have an opinion?
>>
>> NASA computes the current probability of losing a shuttle at 1 in
>> 250.
>
> That's really not very good.
Compared to a commercial airliner, certainly. Compared to other spacecraft
(including the shuttle's *current* loss rate of 1 in 113), it's damn good.
> I certainly wouldn't get on a plane
> where the chances were that it would crash after 250 flights.
Nobody asked you to. The people who *do* board the shuttle know the risks,
and fly anyway.
Chris Bennetts
>> NASA computes the current probability of losing a shuttle at 1 in 250.
>
> That's really not very good. I certainly wouldn't get on a plane where
> the chances were that it would crash after 250 flights.
Neither would I, but the space shuttle isn't a plane. It's a rocket. They're
different things, with different expectations. The space shuttle is doing
very well for a rocket (although that level of reliability comes at a
cost...).
--Chris
Jan C. Vorbrüggen
> ground)
> Payload bay doors fail to close (there's a contingency EVA procedure for
> this)
> ET umbilical doors fail to close (there's a contingency EVA procedure for
> this, but unlikely to work)
The last two are really special cases of the first, and the second is
as well, at least with respect to getting the crew back, correct?
Jan
Proponent
>
> When OTA looked at this a few years after Challenger, if memory serves,
> they concluded that probably the single likeliest way to lose an orbiter
> was a landing accident. There have been three or four close calls. The
> orbiter is not a very good aircraft -- its handling characteristics are
> odd, its landing speed is so high that everything happens very quickly,
> and there is no room for even the smallest mistake in handling or
> misjudgement of weather.
This suggests that Max Hunter's proposed Star Clipper space shuttle,
being a lifting body and therefore probably having even worst landing
characteristics than the delta-winged Shuttle, would have been pretty
accident prone.
What about Max Faget's straight-wing design? "The Space Shuttle
Decision" mentions Faget's concern about lifting bodies' high-speed
landings, so his straight-wing must have had a lower landing speed
than a lifting body. But how did its landing speed with that of the
delta-wing? On the one hand, the delta wing has a large area,
suggesting a low stall speed, but since the straight wing was
optimized for subsonic flight, perhaps *it* had the lower landing
speed.
Henry Spencer
Proponent <Prop...@gmx.net> wrote:
>> they concluded that probably the single likeliest way to lose an orbiter
>> was a landing accident. There have been three or four close calls. The
>
>This suggests that Max Hunter's proposed Star Clipper space shuttle,
>being a lifting body and therefore probably having even worst landing
>characteristics than the delta-winged Shuttle, would have been pretty
>accident prone.
Perhaps. I haven't seen a lot of design detail on Star Clipper. I do
note that it would have had one fairly significant advantage over today's
shuttle orbiter: being mostly empty tanks, its "wing" loading at landing
would have been quite low, which would considerably improve the situation.
Michael R. Grabois ... change $ to "s"
<jrf...@ibm-pc.borg> wrote:
>"Kent Betts" <kent_...@hotmail.com> wrote in
>news:v37dr81...@corp.supernews.com:
>
>> Would the simultaneous loss of all three fuel cells disable the
>> re-entry?
>
>Yes.
Doesn't matter if they're lost simo or not. If you lose all three, you lose all
power to the orbiter, end of story.
>> What sort of failure would preclude a return,
>
>Plenty. Here's some I can think of, in addition to loss of 3 fuel cells:
>
>Loss of all 3 APUs (even loss of 2 is iffy)
>Loss of all 3 IMUs (the orbiter *might* get by on the RGAs, but it's still
>a Bad Day), or the loss of the three flight-critical MDMs that allow the
>computers to communicate with the IMUs.
>Loss of both OMS engines plus two +X RCS jets
Can't you do a deorbit on just 2+X using RCS and OMS prop if that's all you
have left? Granted it would take forever, but still.... Plus you've got fast
flip and the FRCS to help out if needed.
Loss of two ox or two fuel tanks on the OMS, also.
>Loss of thermal protection system integrity
>Loss of cabin pressure (if fast enough)
>Lowering the landing gear while in orbit (can only be retracted on the
>ground)
>Payload bay doors fail to close (there's a contingency EVA procedure for
>this)
>ET umbilical doors fail to close (there's a contingency EVA procedure for
>this, but unlikely to work)
The EVA is likely to work, the big problem is getting out there underneath the
orbiter with only makeshift handholds at best.
>Generic PASS software bug, plus any failure that takes out the BFS (there
>are several)
>
>There's plenty more, I'm sure.
Loss of both freon or water coolant loops is extremely iffy as well.
--
Michael R. Grabois -//- http://chili.cjb.net
"People say losing builds character. That's the stupidest thing I ever
heard. All losing does is suck. " -- Charles Barkley, 9/29/96
Jorge R. Frank
news:3E36B1F5...@cs.ucl.ac.uk:
Right, just separate mechanisms for getting the same result.
Brian Thorn
The fire in Columbia's aft compartment on STS-9 is one, the
short-landing of STS-37 is another.
Brian
Downy
Joann Evans
>
> The rockets blowing up (ala 51-L), meteorite hit, loss of cabin pressure,
> break-up on reentry,
It, uh, looks like you called it.....
> crashing on the runway, or maybe something else? Any
> of you experts in here have an opinion?
>
> (And, just for your information, I ask this out of simple curiosity and not
> because I like seeing things blow up, so please don't flame me.)
Not at all. I'm sure you hate being right on this occasion.
t.stuetz
"Downy" <downt...@yahoo.com> schrieb im Newsbeitrag
news:3E3BFA9...@yahoo.com...
Matt Reilly
> The rockets blowing up (ala 51-L), meteorite hit, loss of cabin pressure,
> break-up on reentry, crashing on the runway, or maybe something else? Any
> of you experts in here have an opinion?
>
> (And, just for your information, I ask this out of simple curiosity and not
> because I like seeing things blow up, so please don't flame me.)
Very very ironic and eery to view this thread today after the Columbia accident...
James Anatidae
news:3E3C02BA...@juno.com...
> James Anatidae wrote:
> >
> > The rockets blowing up (ala 51-L), meteorite hit, loss of cabin
pressure,
>
> > break-up on reentry,
>
> It, uh, looks like you called it.....
Yeah. Hurray for me. :(
I assure you that STS-107 was the farthest thing from my mind when I asked
this question.
> > crashing on the runway, or maybe something else? Any
> > of you experts in here have an opinion?
> >
> > (And, just for your information, I ask this out of simple curiosity and
not
> > because I like seeing things blow up, so please don't flame me.)
>
> Not at all. I'm sure you hate being right on this occasion.
It's a bit spooky, actually. It's like the time I asked a question about
nuclear holocaust movies on a Yahoo! group on Sept. 10, 2001.
--
"I believe that the value of the horse and the opportunity for the horse in
the future are likely to be as great as ever. Aeroplanes and tanks are only
accessories to the men and the horse, and I feel sure that as time goes on
you will find just as much use for the horse - the well-bred horse - as you
have ever done in the past."
- Sir Douglas Haig, Commander of British Expeditionary Force during World
War I, 1926
Squirts
> The rockets blowing up (ala 51-L), meteorite hit, loss of cabin pressure,
> of you experts in here have an opinion?
I would guess that breaking up on re-entry is the most likely
Squirts
> "Kent Betts" <kent_...@hotmail.com> wrote in
> news:v37dr81...@corp.supernews.com:
>
> > Would the simultaneous loss of all three fuel cells disable the
> > re-entry?
>
> Yes.
>
> > What sort of failure would preclude a return,
>
> Plenty. Here's some I can think of, in addition to loss of 3 fuel cells:
>
> Loss of all 3 APUs (even loss of 2 is iffy)
<other thoughts snipped>
The loss of a thermal tile on the left wing should be on this list.
James Anatidae
news:c079e0d9.03020...@posting.google.com...
My thoughts exactly.
Anvil
> Matt Reilly:
>> James Anatidae:
>>> The rockets blowing up (ala 51-L), meteorite hit, loss of cabin
>>> pressure, break-up on reentry, crashing on the runway, or maybe
>>> something else?
>>> Any of you experts in here have an opinion?
>>>
>>>(And, just for your information, I ask this out of simple curiosity
>>> and not because I like seeing things blow up, so please don't
>>> flame me.)
>>
>> Very very ironic and eery to view this thread today after the
>> Columbia accident...
>
> My thoughts exactly.
Tragic for the families and friends and sad to think how this
event will be used as a political crowbar. Not only a setback for
NASA but another obstacle for any civilian experimental craft.
More this underlines design risk in reaching for the stars.
It requires thinking through each component and combination of
"what if". I feel it would be reckless not to ask and question.
What makes the difference is having the will to continue, knowing...
--
Anvil*
We are yet children among the stars,
though are steps may at first falter....
Nate Meier
I'll say...
Richard Lamb
100 years ago, the same price was paid to give us the skies.
100 years from now?
Rand Simberg
Anatidae" <pars...@citcom.net> made the phosphor on my monitor glow
in such a way as to indicate that:
>> NASA computes the current probability of losing a shuttle at 1 in 250.
>
>That's really not very good. I certainly wouldn't get on a plane where the
>chances were that it would crash after 250 flights.
So? How is this relevant to astronautics and what astronauts are
willing to do?
--
simberg.interglobal.org * 310 372-7963 (CA) 307 739-1296 (Jackson Hole)
interglobal space lines * 307 733-1715 (Fax) http://www.interglobal.org
"Extraordinary launch vehicles require extraordinary markets..."
Swap the first . and @ and throw out the ".trash" to email me.
Here's my email address for autospammers: postm...@fbi.gov
Jan C. Vorbrüggen
Less than 90 years ago, it was considered absolutely extraordinary that
Shackleton managed to bring back every single member of his expedition
alive. (Only for at least one of them to die a few months later as a
casualty of world war I.) Such expeditions used to have death tools in
the tens of percent range. How many of Magellan's expedition arrived
home again?
Jan
MattWriter
>home again?
About 18 of the original crew, and one of the original five ships, IIRC.
Surpisingly, though, it was a commercial success - that one ship had enough
spices on it to pay for the whole expedition.
Matt Bille
(MattW...@AOL.com)
OPINIONS IN ALL POSTS ARE SOLELY THOSE OF THE AUTHOR
Andrew Thompson
"MattWriter" <mattw...@aol.com> wrote in message
news:20030204160513...@mb-fp.aol.com...
> >How many of Magellan's expedition arrived
> >home again?
>
> About 18 of the original crew, and one of the original five ships, IIRC.
> Surpisingly, though, it was a commercial success - that one ship had
enough
> spices on it to pay for the whole expedition.
If that shows anything, I think it shows the 'relative cost'
between sailors and spice at the time... :-(
--
Andrew Thompson
http://physci.org/ Home of the Java Physical Sciences Project
& host of 1.1C - Superluminal! (Science and technology site)
Jorge R. Frank
news:v3r89ch...@news.supernews.com:
It was already on the list:
>> Loss of thermal protection system integrity
The tiles are part of the thermal protection system. Sorry if the jargon
confused you.