Remembrance: Challenger STS-51L, January 28, 1986

[RT Atlanta]

25 years ago this morning, the orbiter Challenger exploded shortly after launch on an unusually cold and frosty Florida morning. We lost astronauts Dick Scobee (CDR), Michael Smith (PLT), Ellison Onizuka (MS1), Judy Resnik (MS2), Ron McNair (MS3), Christa McAuliffe (PS1) and First Teacher in Space and Greg Jarvis (PS2).

This disaster was a "JFK" moment (edit: not for the long term damage to our country, but from the context of "remembering where you were") for me as I can remember exactly where I was when I learned of the explosion - sitting in a motel room, sick and "home" from my second day of starting my new middle school, in Mandeville, LA, watching "DC Cab" on HBO in the motel room when my grandmother called to tell us of the explosion... amazing clarity 25 years later.

Godspeed to the astronauts' and their families on this sad anniversary.



Ice on the pad indicating the extremely cold temperatures the morning of launch - cold temps that led to the failure of the SRB's O-ring seal



Tell-tale puff of smoke from the failed O-ring seal on the SRB - this burn-through would ignite the external tank and cause the explosion



Growing burn-through from the SRB's failed O-ring seal



The orbiter & launch stack begins to disintegrate from the external tank's ignition

[trotsky]

1. A very sad day.

Nowhere near as devastating as JFK's assassination, but the Challenger explosion was definitely our generation's equivalent.

[Ian David]

2. Dr. Richard Feynman - Discovers the O-Ring Problem

During a televised segment of the Rogers Commission hearings (on the 11th of February, 1986), Dr. Richard Feynman pointed-out a likely reason why Challenger exploded. Conducting a simple experiment, he revealed that the O-rings were made of a material which was not resilient in cold weather.

This is the actual footage when Dr. Feynman's questioning of Larry Mulloy helped the world to understand what doomed the STS 51-L mission.

More:
http://www.awesomestories.com/assets/dr-richard-feynman-discovers-the-oring-problem


How the inimitable professor solved the mystery of the Challenger explosion.
Mr. Feynman Goes to Washington
January 27, 2006

<snip>

In Feynman’s account, he’s hardly the hard-boiled gumshoe the Senate was looking for. Feynman comes off more like the Chevy Chase-character Fletch, only with a Brooklyn accent, slightly dulled by California living. He was quick with a quip, while ignoring superiors; uninhibited, while always partially out of place with the rest of the commission; and picking up clues, while he bent over to tie his shoelaces. He even arrived late for the Commission’s first gathering when he misinterpreted the address of its location, hearing Eighth Avenue instead of H Avenue, as any native New Yorker may be prone to do.

Aside from his other idiosyncratic mannerisms, Feynman was an anecdotal machine: He always sat up front chatting with his limo driver while being ushered around Washington D.C., and he jabbered constantly with the press while the other committee members quietly hustled out of meetings. He also managed to piss off the committee’s executive director, Alton G. Keel Jr., during their first official meeting. Feynman never did figure out what he said to offend Keel. Classic Feynman.

But Feynman’s half-a-year involvement on the commission will forever boil down to a single iconic moment: His explanation of the malfunction that led to the shuttle’s explosion.

<snip>

Feynman’s witty and highly-edited personal report of the Challenger tragedy was relegated to an appendix of the Commission’s main assessment, but has since come to be revered as a excellent model for risk management.



More:
http://seedmagazine.com/content/article/mr._feynman_goes_to_washington/


Also:

Feynman's Appendix to the Rogers Commission Report on the Space Shuttle Challenger Accident
http://www.ralentz.com/old/space/feynman-report.html

[montanto]

3. Very sad. I remember that day well.

I was at work. We always had a radio on in the office. I remember standing there with my mouth hanging open, which is not something I do. In fact, the next time that happened was fifteen years later, and almost ten years ago now. Remember the Challenger and her intrepid crew.

[TheWraith]

4. The manufacturer of the SRBs knew that the O-rings were unsafe at that temperature...

...and they warned NASA of that fact the day before the flight, and told them not to launch until the temperature reached a safe level for the O-rings.

This letter is written to insure that management is fully aware of the seriousness of the current O-ring erosion problem in the SRM joints from an engineering standpoint. . . . If the same scenario should occur in a field joint (and it could), then it is a jump ball as to the success or failure of the joint because the secondary O-ring cannot respond to the clevis opening rate and may not be capable of pressurization. The result would be a catastrophe of the highest order - loss of human life. . . .

It is my honest and very real fear that if we do not take immediate action to dedicate a team to solve the problem with the field joint having the number one priority, then we stand in jeopardy of losing a flight along with all the launch pad facilities.

— Roger Boisjoly, Morton Thiokol, Inc. interoffice memo to R. K. Lund, Vice President, Engineering titled SRM O-Ring Erosion/Potential Failure Criticality, sent six months before the Challenger launch, 31 July 1985.

My God, Thiokol, when do you want me to launch, next April?

— Lawrence Mulloy, Solid Rocket Booster Project Director, Marshall Space Flight Center, NASA, regards Morton Thiokol's engineers' warnings, 27 January 1986.

(I'm) appalled at the Thiokol recommendation.

— George Hardy, Deputy Director of Science and Engineering, Marshall Space Flight Center, NASA, regards Morton Thiokol's engineers' warnings, 27 January 1986.

If the primary (o-ring) seal does not seat, the secondary seal will seat. . . . Morton Thiokol recommends STS-51L launch proceed on 28 January 1986.

— Joe C. Kilminster, VP Space Booster Programs, Morton Thiokol, after a meeting in which Senior VP Jerry Mason told people to "take off their engineering hats and put on their management hat", by fax to NASA, January 27 1986.

[bananas]

6. Yup

http://www.xavier.edu/newswire/editions/040205/news-whistle.htm

February 5, 2004
Challenger whistle blower speaks

Ann Tassone
Contributing Writer

<snip>

Upon hearing this, Boisjoly advised NASA management to delay the launch. He was told, however, that the launch would take place unless Boisjoly could give convincing scientific evidence to prove his point. They gave him 45 minutes to prepare a persuasive presentation. Boisjoly and one of his colleagues scrambled frantically for enough information and managed to make a powerful presentation, citing the many reasons why launching the following morning would result in disaster.

Boisjoly and his colleague reiterated the point that if the shuttle was delayed even a few hours, the launch had a much better chance of success. If the launch took place at the regularly scheduled time, however, he advised that there was almost a 100 percent chance of failure.

His presentation was not enough to sway the minds of the NASA administration. The general manager, upon getting mixed responses from his team, responded, “Am I the only one who wants to fly?” After this comment, George Hardy, a highly- respected engineering manager, gave his approval of the flight, and the launch remained on its original schedule.

On the morning of Jan. 28, 1986, the space shuttle Challenger exploded after only a few seconds in the air, killing seven astronauts. After further investigation of the disaster, it was concluded that if Boisjoly and his colleague had more time to prepare a swaying presentation, they could have scientifically proven that because of the Challenger’s design and situation, the rate of failure for the shuttle was 97 percent.

<snip>

[Kaleva]

5. i was in Philly on the mess decks of my 2nd ship watching the launch.