Shuttle Disaster 1

[KLH]

Is it true that the foam insulation that struck the shuttle wing was going +500 mph?? (According to the reports on CNN anyway.)

At the time of the foam separation, both the shuttle and the insulation were moving at the same velocity.

When the foam insulation separated, did its velocity slow enough in that short time (between separation and impact) so that the relative velocities of the shuttle and the insulation exceeded 500 mph?

Can someone explain this to me?

 

[CusterWilson]

Challenger was killed by the small explosions in the fuel called "Combustion Instability". However of the 7 known holes in Challenger's side 5 clustered at spots (the struts) Ali calculated overstresses at -- and (see the pictures in the May 1988 Spaceflight) one of these burned a hole in the wing which WOULD have killed her.
Columbia was killed by an almost identical hole except in the left wing -- the explosions using the weakened area as a preferred path was an accident waiting to happen.
Columbia was thus killed by the Challenger Panel Majority, who buried the details & ended their "Final Review" in mid-April the day before even the chemical report on the first joint piece was available (guess what: they found NO O-ring markers in the soot. They never leaked. That flight. The critical ananlysis of cracks in the ET was dated 3 weeks later.

Now Combustion Instability has: blown holes in 3 of the 4 Shuttle-equivalent Expendables, almost killed Challenger earlier in its flight by a thrust mismatch nearly flying it sidewise to the wind -- and a mismatch occurred again on Columbia. Also (see my replies at the end of the other 2 Forums (use keyword Columbia) the SHAKING probably caused LH2 to migrate past valves in the fuel cell interconnect system, blowing the electrical system on Columbia and foiling the gutsy Pilots' restabilization of Columbia 30 seconds after the wing broke in half --- in this I am cribbing NASA's research on the last large Mars Mission (Mars Observer died from a fuel migration-past-valves problem obviously the result of violent SRB shaking).

Ali's Transient overstresses can also kill directly.
Ripping the 2068 ET seam should kill about 1% of older ETs; Accellerated wear-and-tear is Constantly being uncovered (I am glad Ali broadened his argument since last I had contact -- I pointed to the Main Engine bearings: but I had no idea there was so much more.
Nonetheless there is not as much as you believe:
1. Companies typically add 40% to ALL strengths, fearing becoming a WorldWide Pariah like the Apollo 13 Low bidders.
2. Liquid Thrust is 40% higher at altitude.
3. 10% was added to account for Transients
--- note, not assessing them was sloppy, but the whole Moon program was a race between the USA upgrading fuels & the USSR increasing engine pressure -- the Shuttle combines BOTH, and the jump to a high-pressure engine resulted in SURPRISES -- such as a 59% overrun when 10-15 was experience. Similarly "Escape off the Solids" always assumed the Liquds would shut instantly because they always had ... Challenger's orbiter's near-escape on only 1 engine shows how easily one can use them for escape and, in Idle mode & with Centaur CH4/LH2 OMS (Lunar & Zubrin's Mars Direct landers could use the SAME engines) for up to 22,000 lb net cargo (with the Al-Li ET, 4000 lb to "108-degree reverse Sun-synchronous (Military) orbit" becomes 33,000).
4. Standard 15% margin (40% where poorly understood).
... now Thiokol used the latter, +40% = 194% strength or 94% margin vs 70% Transient for the Solids ... Liquid stresses used 115% x110 (x140% for thrust), x140 = 248 or +148% margin vs. 59% -- but only 77.1% for sideways thrusts where +40% thrust, does not apply.
... now the welding flaws in seam 2068 halved the usual 40% Company extra, which was informal & optional, after all (ie they were 20 & 30% stronger than NASA specs) ...
---NOW NOTE WELL: attempts to use expendables to fly Shuttle-sized cargos DO NOT have that extra 40% margin (of course they also rarely have a 3-legged cross-stress) which explains why only one ever reached orbit -- and at that a VERY low one -- and all have had their cases thickened to where they can not take the large Miltary Satellites. --

Now if Challenger's descent to 20% margin was closer to the strut: Goodbye on the Pad ... as it was, the cracks came from above & went Through the flaws, but it still caused That seam to split Prior to the one above where the ET's problems started. That bouyed the Commission argument that flames from the visible O-ring hole hit the ET at the repressurization line, melting the tank yet dropping the Pressure (the line is on the BACK LEFT but they argued the vehicle is flying upside down -- kind of like saying when you turn around ONE of your eyes moves to the back of your head) (Feynman disagreed, suggesting SRB hole gasses which cut Strut strength in half broke it which compromised tha ET in a vague way --- BUT, the strut broke on the (unheated) ET side, implying an IMPACT faster the speed of sound in metal, i.e. ejecta from a hole higher on the side (not unlikely the very chunk of fuel whose shrinkage caused the pressure spike that blew out the side and pierced the ET -- Challenger had a LOT of ground damage from such chunks).
In short, both the fuel problem, & Transients, have to be avoided or fixed --
... there are MANY possible accidents if these two root causes are running wild, enough for the Bureaucrats to claim the next 'doesn't look the same' so it is "another NASA slipup", EVEN THOUGH vitually identical damage happened to both Challenger & Columbia, damage which any REAL investigation (not one excluding Rocket Scientists) would not have buried, but FIXED.
My nightmare is losing all 5 Shuttles, ALL blamed on "NASA" if there is 1 of each of the accidents I have cited above (hole by strong explosion, hole by moderate explosion POINTED at wings by weakened area near strut, thrust mismatch, ET seam rip on pad (the only one to be fixed -- partly: struts still might break), and: repeated explosions migrating fuel past valves.
Remember, the same man headed ALL investigations at NASA until fired by the Challenger Commission Majority, first day. Also that Rocco Petrone cancelled Challenger's Launch --the people who Fixed the Panel evidently ordered he not be informed when they called everyone else back but it appears in records because he assured Thiokol their inability to get good calculations ruling out the Cold should not dismay them -- he'd already planned to cancel it (at least partly for the Right reason: it was too much like STS-4 when they lost both solids & shook so bad any cargo would have been glitched, plus the Low orbit from Low SRB performance we saw again in Columbia & the Delta lauched just prior to it .. literally, he said "too many things close to the edge&quot.
So I consider the Institutional Cause of the accident is not NASA but the EXCLUSION of the non-politicised Hard-Science NASA people, the Congressional elimination of NASA's Overrun Protection, the cut by a factor of 13 in Space Science, the loss of the NASA Administrator's Reserve, and the constant cancelling of critical upgrades ostensibly for Budget reasons, but often because FIXING anything means Admitting a Mistake...

But, again, Transients "only" caused fatal damage to Challenger.
A simple fuel explosion inside the SRB, blew her ET.
Before the Transients could kill them ala' Columbia.

Columbia saw the mainly-Transient-caused, back-of-the-Wing-roasting, return, to preempt a possibly fatal Fuel-cell leak.
-------------

... in re Shuttle sucessors -- I love SSTOs, but they run so close to materials technology limits ... will Transients be too much, since the extra 40% the companies have tacked on our Shuttle looks impossible?
Or will air-launch or slow thrust-buildup avoid the Transient problem?

 

[JimMetalsCeramics]

CusterWilson,

Do you have a copy of DesignError.PDF?

 

[CusterWilson]

Jim: I was thinking of requesting it though at first I thought I had it directly from Ali in hardcopy 14 years ago; yours seems to be a bit updated (at the time Ali was perhaps overly concerned with the ET seam busting at Launch whereas wear on the main bearings, etc, provided so many routes not even just to destroy, but to degrade Shuttles -- i am afraid I am somewhat callus in considering Program Slowdowns in the same breath as Fiery Astronaut Deaths but ... the Lifespan Effects of a lack of Exploring are 1 Billion years/per/year or 15 million equivalent Lives, by my count (the difference between .3 years gain per year & .1 year/year).
So: I need one, but tell me how to retrieve it, I am new to post-Dos tech & my cable service stores the E-mail: I can read it, or connect to the source & download but it doesn't go direct (? or am I misinterpreting). So explain a bit or show me a site I can save from.

And one REALLY powerful thing you could do is if you could find Ali himself for me -- I have tried Web searches but it seems like he is not on-line.
That stuns me: like: he called this! The Proximate Cause .. we have a Picture of it (a red flame seen through the crack between the wing of Challenger & her aileron, see his article May 1988 Spaceflight (I had a letter in June 1989 -- so far as I know these are the Only dissents to the Challenger PAnel's Explanation. If the Columbia Panel was Honest they would have HAD to include him, and maybe even me, just on that basis (ignoring Feynman's vaguenesses))).

 

[JimMetalsCeramics]

Send me an email at jintrater2@yahoo.com

 

[JimMetalsCeramics]

If you post your email, I'll send you a current copy of the paper.

 

[unclesyd]

Here is some pretty good information on the Columbia disaster.
You can back out the official website

http://www.caib.us/news/documents/impact_velocity.pdf

 

[JimMetalsCeramics]

Falling debris may have caused the pivotal damage on Columbia (I don't understand how such large relative velocity was generated so quickly, though). But there is a widespread problem that the pre-launch, launch and in-flight loads were inarguably, severely undercalculated. Any avoidance of this issue is a whitewash.

 

[cab1990]

The Columbia failed due to an impact of foam on RCC panel 8 or 9. The foam was traveling at 500-600 MPH. Currently the number being evaluated is 545 MPH. This speed was the result of a drop in velocity of the foam due to aerodynamic drag forces. (rather large in shape but, light like a feather) which broke off at ~1800 MPH. When it hit the wing it was traveling at ~1200 MPH.

Tests at Southwest Reaseach Institute consisted of shooting a piece of foam at panel 8 at 1100 ft/sec and it blew a hole into the leading edge that was 12"x15". Clearly this proved that the foam was capable of causing the damage that would allow the 3000 degree rarified gas flow to melt the wing structural components. By that way, this was all on a CNN special which I guess everyone missed. If you really want to find out how NASA engineers tested, evaluated, and determined the root cause of the Columbia disaster take a look at this web site:

http://www.caib.us/news/report/default.html.

 

[CusterWilson]

The CAIB rigged the test 3 ways:
# 0. They DID use real foam against a real RCC panel, at the real speed ... BUT:
#1. Despite Cameras showing the Foam breaking up into a cloud 8 feet wide by 20 feet long ... they used a SINGLE slug, long and narrow (& wrapped in tape, too) so that its narrow end (about a half square foot) hits the RCC with hundreds of times the IMPACT PER AREA that it should.
#2. They used a compressed air gun that gave a uniform, continuous accelleration -- in contrast the REAL foam is WHACKED by a 1550 mph Turbulent Wind (the Orbiter and the ET are only 3 feet apart throughout the foam's 60 foot journey) -- it must be like being hit by a dozen Force 10 tornados.

You see, the whole point of the Foam is that if NASA leaves it off, they get ICE: and ICE may act much like this phony artificial "slug" -- stay in one piece, and hit like a spear on the pointy end (remember Icicles?).
They never show the slightest reason why the Foam would act differently from its designed role (which is: TO BREAK UP). Every Other flight, theory, model, test, and even camera pictures ... show that it would and DID break up. The phony "controversy" over the foam's speed is just Misdirection.

Yet even THIS WAS NOT ENOUGH.
The impacts still made only hairline cracks.

#3. They used a nearly doubled impact angle to break through: Columbia's accellerometers measured an impact equivalent to 1.5 pounds at 16 degrees but to break the RCC panel they up'd it to a 26-or-30 degree angle(respectively "incident" and "clock" angles: the panel is rapidly curving at that point, what they mean is unclear)
... what was their excuse?

They say the FOAM rotated -- like a rigid bar -- in a 1550 mph wind -- and the rotation ADDED to the impact.
Now think: at their 18 rpm the 0.17 second trip saw 3 complete rotations -- one end of this 22 inch bar is moving with the wind, but the other is moving AGAINST the wind -- really !
It HAS TO BREAK !!!!
Even steel would probably bend.
The fact is,
A) we have never seen more than coin sized pieces
B) the piece immediately behind the CAIB hole -- carrier panel #8 -- WAS FOUND -- and found: "NEARLY PRISTINE"
C) If the hole is on the underside of #8, why are top pieces more likely to be missing and generally Much more badly damaged (e.g. the two charred remnants of the UPPER Carrier panel #8)?
D) The wires die Top Down, not bottom up (oh excuse me I have already been critisized elsewhere on this: they did not say it that way: the CAIB reports says: in sequence "vertically toward the underside" -- not "Top Down" -- like as if that is different).
E) Although most of the lower half of RCC Panel #8 is missing, like with RCC #9 the edges are mostly present and are ablated only facing the #8/#9 seam. All the edges facing the supposed hole are broken, not ablated.
F) We already lost a t-seal on an Atlantis flight, so we know the gap between #8 and #9 -- obviously the ONLY hot air entrance -- must have been PULLED APART SEVERAL INCHES.
As only the usual strains are present, the wing must have already weak from damage recieved weeks before in the ascent, probably associated with and centering on the "elevon actuator" hole (the near twin of Challenger's Aileron hole) -- which hole the CAIB refuses to mention, and always Obscures, in detailed diagrams of the pieces (with the NASA Logo, or "whiting out" most of the top view).
As you may be able to tell, I have been "mining" the CAIB report's Appendixes for details ... did you know there is an EXTRA "first" sensor to show problems (that the CAIB supressed)?-- along the line of where the wing broke off, it is the rearmost strain guage, reacting 10 seconds before its counterpart on the leading edge. Boeing's initial judgement was overruled.
Note, the line the wing broke off on, was heavily instrumented.
... that both ends of this string would go, with No changes in the middle dozen strain guages, and well before ANY temperature guages show changes ... The politicians HAD to supress the rear strain guage reading: it makes too clear a pattern.

 

[JimMetalsCeramics]

I like CusterWilson's manner of engineering investigation.