CMP.WERNER@R20.UTEXAS.EDU (Werner Uhrig) (01/28/86)
enclosed a message from Peter Neumann just posted to RISKS, which mentions an automatic self-destruct mechanism. Not that I suspect that mechanism as being at fault in this case, but I still think it is an "unmentioned topic" worth looking into. (ever thought that such a mechanism built into an airliner could prevent highjackers from crashing it into downtown *whereever*? how would you feel about riding on such a vehicle?) In a few minutes, I also hope to post an article raising some questions about the "apparent" lack of concern about icing on Challenger and some observations which could point to ICING as related to the explosion. NO-cheers from this pilot today, )-: Werner --------------------------- Tue 28 Jan 86 09:45:12-PST Peter G. Neumann <Neumann@SRI-CSL.ARPA> The Space Shuttle Challenger (738 chars; more?) For those of you who haven't heard, the Challenger blew up this morning, 1 minute and 12 seconds after launch, during maximum thrust. Everything appeared to be working properly. TV pictures show one of the solid rocket boosters on the side going first, then everything. (There had been some concern because the temperature went below 28 degrees Fahrenheit during the night at Canaveral, and that temperature is considered critical because of ice formation.) The Challenger had consistently been the most reliable of all the shuttles. One unvoiced concern from the RISKS point of view is the presence on each shuttle of a semi-automatic self-destruct mechanism. Hopefully that mechanism cannot be accidentally triggered. -------
kyle.wbst@XEROX.COM (01/29/86)
Your mention of a destruct mechanism on airliners to foil hijackers raises the question of possible terrorist activity in the shuttle explosion. With the recent flap involving Libya, how certain are we that the radio code that the Air Force range safety officer uses to destruct shuttles gone astray was not compromised? Although the slow motion video indicates some other mechanism besides on board explosives initiating the destruction of the vehicle, I'm wondering if a high powered rifle bullet hit either the main fuel tank or one of the solid boosters shortly after launch if that could have given the same result we saw yesterday. What makes me think of that is the following: When I went to the 4th shuttle launch (STS-4), I noticed that things were quite different in the press site area (where I was) than it was for the two Apollo launches I attented (A-11, & A-17) in that same area. The difference at STS-4 was the large number of armed guards. When I asked about that, the reply was something to the effect that there had been some intelligence that someone with a high powered rifle might try to shoot at the thing during takeoff. As the shuttle flights got more routine, I'm wondering if the security at the site got a bit lax? Does anyone know if a rifle shot on the big tank would be enough to structurally weaken it such that during that portion of the launch with maximum stress the thing might rupture?
aviation@ucbvax.UUCP (01/29/86)
In article <12178909248.29.CMP.WERNER@R20.UTEXAS.EDU> you write: ...previous lines deleted (not germain). > >One unvoiced concern from the RISKS point of view is the presence on each >shuttle of a semi-automatic self-destruct mechanism. Hopefully that >mechanism cannot be accidentally triggered. >------- Please Note, and cease to spread your unfounded rumor! ONLY the SRBs and the MFT/mate assy have a destruct mechanism. The shuttle is NOT provided with such a mechanism, any more then an L-1011 is! ------------------------------------------------- Dusty Bleher (@@) (408) 395-6616 x265 (wkdays PST) -------------------------------------------------
LIN@MC.LCS.MIT.EDU (Herb Lin) (01/30/86)
From: kyle.wbst at Xerox.COM
Does anyone know if a rifle shot on the big tank would be enough to
structurally weaken it such that during that portion of the launch with
maximum stress the thing might rupture?
It is obvious that at the time of the explosion, no rifle bullet hit
it. Thus, any shot must have been fired much sooner. The rifle shot
must then be timed in such a way that it is fast enough to weaken the
casing, but not strong enough to penetrate it. It seems that that
window is pretty small.
If you are into pure, unadulterated speculation, another possibility
is that a bullet was fired while it was on the ground into an SRB, and
lodged there. When the fuel burned to that point, a jet leaked out,
and triggered an explosion.ladkin@kestrel.ARPA (01/31/86)
Those interested in the shuttle's self destruct mechanisms should read the RISKS digest 1.43 (or 44?). RISKS is moderated by Peter Neumann at SRI-CSL, and requests should be sent to RISKS-REQUEST@SRI-CSL. As a group, we might occasionally have articles to contribute ourselves on risks in increasingly- automated avionics systems. Peter Ladkin ladkin@kestel.arpa
ladkin@kestrel.ARPA (01/31/86)
In article <8601291750.AA06647@wayback.amiga.uucp>, aviation@ucbvax.UUCP writes: > Please Note, and cease to spread your unfounded rumor! > ONLY the SRBs and the MFT/mate assy have a destruct mechanism. The shuttle > is NOT provided with such a mechanism, any more then an L-1011 is! > Indeed the shuttle is provided with a destruct mechanism. See my previous posting for a reference. Peter Ladkin ladkin@kestrel.arpa
c-hunt@tesla.UUCP (Charles Hunt) (01/31/86)
No rifle bullet caused the Challenger explosion: 1) a shot on the ground would have produced detectable damage before launch 2) the shuttle exploded far out of range of a high-powered rifle on the ground 3) the airspace near a launch is tightly controlled (no airborne rifles) 4) security in the area is so tight, it's obscene 5) cape canaveral is in the most vermin-infested swamps of our nation (coral snakes, copperheads, gators, etc.) even the cleverest frogman terrorist would not get far around there. (let Quaddafi try: he'll get his reward!) =Charles Hunt=