Talk:Space Shuttle Challenger disaster/archive1

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Image suggestion

Consider using this image of ice on the launch complex. Ke4roh 13:43, 17 Dec 2003 (UTC)

That would now be this image of ice on the launch complex. (NASA has re-jiggered their image archive and no longer uses the 8-digit photo ID.) --Chris Lawson 09:13, 24 Jan 2005 (UTC)

Hydrogen flames

Rmhermann- I think that its more accurate to say that clear hydrogen flames enveloped the orbiter, rather than smoke. Whats your rationalee for changing it? Theon 14:44, Mar 3, 2004 (UTC)

Hydrogen flames are pale and are not shown in the picture. What we see in the picture is smoke. Rmhermen 14:46, Mar 3, 2004 (UTC)
It might be more accurate to say smoke and steam, since the invisible/blue-white hydrogen flame produces mostly steam. Then again, many other things (including impurities in the atmosphere) are burning and producing smoke. -- Ke4roh 18:56, 3 Mar 2004 (UTC)

Politics Accident connection

This may be a stresh, but can actually turn to be very important trigger for further research in future. Some people seem to think that the lanch of STS-51-l in such a cold day was politically driven. See this comment [1]

I've heard this claim many, many times; it's not generally accepted to have any validity, and I've yet to hear of plausible evidence being presented for it. Reagan was aware of the program, and interested in it - IIRC he knew what launch it was when told of the accident, which says something - but he doesn't seem to have ever personally poked around with it, nor has there ever been much other than assertions regarding the plans for the State of the Union address.
There was pressure, internal pressure within NASA (a lot of it silent, but certainly there) to keep up the launch schedule; gven the speeds they were trying to manage that year, this isn't surprising. It's probably defensible to call this political pressure, but it certainly wasn't external political pressure for the launch. (If nothing else - if it was vitally important she launch in time, why not push the day before, when there was a scrub? Why this one specifically?) Vaughan's The Challenger Launch Decision goes into this in some detail.
It's also a fairly silly article - yes, NASA has postponed launches for things much less dangerous than ice. This is because they are now, understandably, a little more paranoid about the resiliency of the system post-Challenger. Also, without meaning to sound too cynical, Slashdot's validity as a source of space history is, ah, disputable. I've read a statement there presented as fact that Buran was all a carefully-planned Soviet hoax... Shimgray 15:08, 25 Jan 2005 (UTC)

Physics Today did an investigation of this. They found considerable telephone traffic originating at Blair House. Thus, you need to ask V.P. G.H.W. Bush exactly what requests he made to NASA re: State of the Union Speech. I will Google this if no one else wants to, but I talked with a Senior Editor who confirmed the launch was pressured because President Reagan wanted to talk to S. Christa McCaluliffe live duirng his speech.

John G. Magee

Reagan's famous speech quotes the poem "High Flight" by John Gillespie Magee, Jr., maybe this should be mentioned.

Done as of this afternoon, after an anon stuck it in a weird place and reminded me I needed to do it.—chris.lawson (talk) 03:00, 8 August 2005 (UTC)

Time of impact

Hello. Maybe someone can find out the time of impact of the crew cabin and add that to the article. All the best, Wile E. Heresiarch 20:40, 12 Jun 2005 (UTC)

Copied text

Much of this seems to come from [2]. I assume this is PD, and therefore okay to use, but it shouldn't it at least be credited? -- uFu 19:46, 15 July 2005 (UTC)

That would be an excellent idea. You wanna do it, or should I? Also, I didn't mean to sound snippy in my revert of your earlier reversion -- I think the anon who added that tidbit was well-intentioned but probably just put it somewhere it didn't best belong. If you (or anyone else) can think of a better place for it in the article, please move it.—chris.lawson (talk) 21:48, 15 July 2005 (UTC)

Cultural impact

Is there a WP article which discusses the cultural impact of the Challenger disaster? A survey released in the mid-1990s found that this was the most profound childhood event of the so-called Generation X, and is speculated, for instance, to be related to that generation's supposed distrust of institutions. Hoping there is as it would take some time to research a new article.- choster 05:42, 5 August 2005 (UTC)

"Second" vs. "seconds"

Gene and I had a discussion about this a while back, and I (apparently dumb, retarded and asinine) assumed that he had decided to leave it alone.

Unfortunately, that seems not to be the case.

Gene insists that the "timestamp" of 678 thousandths of a second after launch be referred to as "0.678 second," quoting an obscure NIST publication that he interprets to mean values from -1 to +1 (exclusive) should be rendered in the singular.

I, on the other hand, am relying on my real-world experience in the scientific community as well as the opinion of a highly respected copyeditor for the Washington Post, who also happens to have written several popular books on such topics in asserting that the word "second" in that case should most definitely be plural; i.e., "0.678 seconds."

Can we get some consensus up in this piece? :) Thanks.—chris.lawson (talk) 11:20, 8 August 2005 (UTC)

It's not -1 to +1 exclusive; those endpoints are included, but it is one of the quirks of English that zero is not included—that is plural. Another way of saying it is to use the singular with numbers whose absolute value is greater than zero and less than or equal to one.
NIST Special Publication 811, Guide for the Use of the International System of Units (SI), is hardly an "obscure" publication in the world of measurements. It is often cited not only by me and other Wikip[edia editors, but also is highly recommended by the National Physical Laboratory,[3] the U.K. national standards laboratory, and by the BIPM, [4], the international keepers of our standards.
That well-respected style guide is certainly more reliable than a private communication with some retired individual.
It is a rule followed by
  • Webster's New World Dictionary, 2nd college ed., 1970, in Tables of Weights and Measures, p. 1688: "0.0254 millimeter" but "2.54 centimeters".
  • Merriam-Webster Online Dictionary, s.v. pound: "equal to 16 avoirdupois ounces or 7000 grains or 0.45359237 kilogram".
  • BIPM webpage on "Base units": "0.012 kilogram of carbon 12", "1/683 watt per steradian", " 2 x 10–7 newton per metre of length".
Many, many others. Gene Nygaard 13:58, 8 August 2005 (UTC)
It's obscure in that I have yet to see its guidelines followed in one single scientific journal article, and making ad hominem attacks against Bill Walsh isn't helping your case. Argue the point, not the person making it. Again, common usage goes against the NIST guideline.—chris.lawson (talk) 14:08, 8 August 2005 (UTC)
Is this level of detail really necessary anyway? The way to solve the dispute may be to just say "Fractions of a second after liftoff..." Most casual readers won't see much difference. · Katefan0(scribble) 14:10, August 8, 2005 (UTC)
Probably, since the timeline is detailed so precisely throughout the rest of the accident description. It would seem rather odd for the initial event to be described so vaguely.—chris.lawson (talk) 16:39, 8 August 2005 (UTC)
It is precisely about Bill Walsh (who is neither of those at this link) and his opinions, and whether or not they are available to and used by anybody (and so far, at least, you have provided no evidence that they are), and whether or not he is influential enough to persuade anybody (even his former? employer, for that matter) to follow him, even if they would ever find out what his opinion is. The NIST guide, OTOH, is credible, authoritative source, one readily available in html, pdf, and even a free printed version, and much followed.
It isn't just NIST. Other style guides include the same rule; eventually I will find some of them, or someone else will.
I have, of course, already provided specific and uncontroverted evidence of other reliable authorities following this rule. Gene Nygaard 14:48, 8 August 2005 (UTC)
So now you're not only making ad hominem attacks, but you're making an appeal to authority as well. If you don't know who Bill Walsh is, that's not my problem. I already told you who he is, and it's not my fault he doesn't have a Wikipedia page. Again, if you can cite any scientific journals that actually follow the NIST style guide, please do so.—chris.lawson (talk) 16:22, 8 August 2005 (UTC)
I realize this addition is both late and moot (since the 0.678 seconds was removed.) But I'll add my take on it for future reference. It's true that generally, when the value of a measurement is less than unity (plus or minus), the associated unit should be singular. However, this 0.678 was part of a timeline measured in seconds; therefore, using the plural form was correct. --ChrisWinter 23:09, 26 July 2006 (UTC)

Name of this article

Maybe we should rename the article from "STS-51-L" to "Space Shuttle Challenger Disaster". 204.52.215.107 00:24, 10 August 2005 (UTC)

In light of the fact that the only other similarity -- the Columbia disaster -- is named "Space Shuttle Columbia Disaster", I would certainly support such a move. "STS-51-L" doesn't mean a whole heck of a lot to most people outside NASA.—chris.lawson (talk) 03:43, 10 August 2005 (UTC)
In the case of Columbia, we have seperate articles for the mission - STS-107 - and the disaster - Space Shuttle Columbia disaster. This is because the mission was, until re-entry, pretty much the same as any other in terms of what our articles cover - so it's worth having a seperate article for it.
Conversely, the STS-51-L mission lasted about two minutes. There's almost nothing that could be said about the mission which isn't directly linked to the accident, so the two pages are the same. I am surprised there isn't a redirect from Space Shuttle Challenger disaster, though. (There is a redirect - I just missed it, oops)
Using STS-51-L is consistent with all other Space Shuttle mission articles (which reminds me - I need to write the article on NASA mission numbering I've planned...); personally I'd prefer to keep the page at STS-51-L - the name is explained in the first line - and keep a redirect as above. Shimgray 14:41, 10 August 2005 (UTC)
I agree with the reasoning on the mission and disaster basically being one in the same -- I don't really have a preference for which should be considered the main article and which should be its redirect, although since it's already located here I'm inclined to just prefer to retain the status quo. As long as there's a set of redirects that folks would logically use to direct them to this article, I don't see any real harm. Actually my only quibble with the naming is the hyphen between STS and 51. I've always seen it written either STS 51-L or STS 51L, but never with a hyphen between STS and the number. A cursory Google search reveals plenty of variation within NASA's own sites, so I'll leave this one for folks more familiar with the numbering scheme than I. · Katefan0(scribble) 14:52, August 10, 2005 (UTC)
It's for consistency, really - NASA didn't tend to number these missions STS hyphen number, but the "plain" numbers - STS-1 through 9 then 26(R) through today - are often written with hyphens (certainly I usually do so), so it gives consistency in naming. It's not a major issue, though - we don't hold to the "official" numbering for Gemini and Apollo flights where those used Roman numerals rather than Arabic (they changed in the middle of the Gemini program!), so a hyphen here or there is trivial :-) Shimgray 15:05, 10 August 2005 (UTC)
Sorry guys, if Linda Susan Boreman has go by the name "Lovelace" forever, then so does this thing.

Google sez on exact match:

  • "Challenger Disaster" - 335,000
  • "Challenger Accident" - 142,000

I personally recall "Challenger Accident" as being more common at the time (I was in Melbourne, Florida -- 10 miles away from the launchpad -- at the time, but missed the flash of the detonation itself), but maybe my perception is narrow. Anyway, I am going to rename the page to what it is "most commonly known by" these days. -- Fplay 16:10, 13 December 2005 (UTC)

I disagree we have any real reason to move this away from STS-51-L; see comments above. We need to differentiate between the Columbia accident and the preceding mission; we don't need to differentiate between the Challenger accident and the mission itself, as the latter had no independent existence. I can understand that "accident" and "disaster" should both exist as redirects, but I don't see that any reason to move the article has actually been given.
If we must rename the article, then "Space Shuttle Challenger disaster" would probably be best for consistency with Columbia. Shimgray | talk | 16:27, 13 December 2005 (UTC)
It is kind of too bad since the defining document CAIB, calls it "Columbia Accident". The reason for the move is because it is a defining moment of the 20th Century. Millions of people, inluding millions of schoolchildren, saw the explosion as it happened. It is right up there with the Pearl Harbor and the falling of the Berlin Wall. -- Fplay 16:36, 13 December 2005 (UTC)
To be fair, the CAIB couldn't call it anything but "Accident" - if they'd referred to it as anything else, their Presidentially-mandated name would have looked a bit odd :-)
Compare other spaceflight fatalities - we have Apollo 1 not Apollo 1 disaster; Soyuz 11 not Soyuz 11 disaster, &c. STS-107 is split to be an article on the "main mission" and on the breakup-and-aftermath because it would have been stupidly long otherwise, and it was the natural way to split; however, for 51-L, the main mission can be covered in a paragraph. Consistency would suggest we should keep the article at 51-L and redirect from all plausible forms of "Challenger disaster", "Challenger Accident", &c. Shimgray | talk | 16:45, 13 December 2005 (UTC)
For perspective, try this: Detailed logarithmic timeline . Which accident shows up? This one. -- Fplay 18:10, 13 December 2005 (UTC)
Yes... I'm not entirely sure what you're getting at. I haven't argued it wasn't a significant event - only that we already have an implicit house style for titling articles like this. Shimgray | talk | 22:48, 13 December 2005 (UTC)
  • FWIW, I can see the attraction of "STS-51-L" for consistency with articles for the other Shuttle missions, but in this special case I think "Space Shuttle Challenger disaster" would be best. The recent move to "Challenger Disaster" has left lots of double redirects in place. -- ALoan (Talk) 17:36, 13 December 2005 (UTC)
I acknowledge that consistency with the "Space Shuttle Columbia disaster" (lowercase "d") page would benefit the reader. I will rename it to that and fix the redirects. Yes, there are many redirects, but the rules fo "Linda Lovelace" and "Stepin Fetchit" apply to this also. -- Fplay 17:54, 13 December 2005 (UTC)
Oops! "Space Shuttle Challenger disaster" redirect already exists as redirect, so we will need some admin help here. -- Fplay 17:58, 13 December 2005 (UTC)

Revert?

Should this article be reverted? On Nov 10th BoringGuy did a "complete rewrite" and threw out almost all of the existing content. There's stuff missing now that was there such as issues about the cabin and the state of the crew. Mperry 01:43, 15 November 2005 (UTC)

You can use the information on this site to write up a section on the crew.
The problem with your changes is that massive portions of the original text were thrown out without any discussion here. That type of action is frowned upon on Wikipedia. Also, elements such as the links to versions in other languages, and the category tags, were removed (why?). Users are encouraged to discuss major changes before starting on them and then to leave a summary afterwards. That didn't happen here. No discussion about those changes took place. Unless there's a compelling reason not to I agree the page should be reverted within the next several days. Also, please sign your posts (append four tildes) 67.127.180.230 21:32, 19 November 2005 (UTC)

The big re-write was:

  01:44, 10 November 2005 BoringGuy (Complete re-write to be technically accurate)

so maybe we can work it out with him. -- Fplay 18:12, 18 December 2005 (UTC)

Can this ever be a featured article?

I think we can whip this page into shape and get it to be a featured article. Some ideas:

Does the RSO and SRB stuff belong in the lead paragraph? I think not, but I will give a few days for feedback. My point is: The engineer details of mission are not important because the mission was a total failure. What happened that was historically important should be in the lead paragraph. It is not that I want it to read like a news article, but the historically important stuff belongs at the top. -- Fplay 16:26, 13 December 2005 (UTC)

The intro is massively technical, and could do with being pared down. It uses internal STS numbers, which are hardly even of academic interest, is far too precise, and so forth. This article was very heavily rewritten, almost from scratch. in the last month, and I'm doubtful it was actually a useful improvement... I'm tempted to just revert back at times. Shimgray | talk | 16:58, 13 December 2005 (UTC)
Well, now that the page has an appropriate name, the engineers with their pocket protectors and slide rules will take a hint, and if they are still all atwitter, they can telex each. I agree that the lead paragraph from 6 months ago was better. The rest of the article can be technical as it wants to be, because many readers will never get that far. I mean, even amonst us nerds, how many of us actually got through the CAIB report? -- Fplay 17:23, 13 December 2005 (UTC)
>raises hand< But only because I had to. · Katefan0(scribble)/mrp 20:32, 13 December 2005 (UTC)
All seven crew members were killed when their surviving and slowly tumbling crew compartment impacted with the surface of the ocean.

Now, the "and slowly tumbling" phrase does tend to give the reader motion sickness and make them want to puke, and that is what the astronauts experienced as they helplessly, and probably only at intervals, watched the surface of the ocean approach. Not fun, but that is what happened. That is, of course, after the compartment reached apogee, since the compartment, and most of the other pieces, continued to ascend for a while. The question is: should the phrase be included or not?

The most recent documentary I have seen on this indicates that the crew likely lost consciousness seconds after the "explosion" due to decompression. --Vernon 05:08, 24 January 2006 (UTC)
Correct. Time of useful consciousness at various pressure altitudes is well studied. The FAA and military obviously do many tests, since the same issue affects pressurized high altitude aircraft. How many seconds you remain conscious following cabin depressurization at various altitudes governs safety rules, aircraft emergency oxygen, etc. The Challenger accident happened at 46,000 ft, and the crew cabin peak altitude was about 65,000 ft. Time of useful consciousness at 46,000 ft is about 8 to 15 seconds, assuming no other problems. It is physically impossible they were conscious much longer than that.Joema 14:27, 24 January 2006 (UTC)
Is it possible some of them regained consciousness as the capsule entered lower altitudes. I read an account of the Lockerbie bombing that suggested passengers had regained conscious before impact.--Chris 19:51, 28 January 2006 (UTC)
That seems pretty unlikely, assuming the detached shuttle cabin lost pressure integrity. The Lockerbie 747 exploded at 31,000 ft and fell immediately downward.
By contrast the Challenger breakup happened at 46,000 ft while ascending upward at about Mach 1.9. The cabin trajectory peaked at 65,000 ft, and time from breakup to water impact was 2 min 45 sec. Terminal velocity at sea level was about 200 mph, so extrapolating backward they were probably above 30,000 ft for about 100 seconds. For a brief period they were above the "Armstrong line", whereby blood boils unless you're in a pressure suit. During descent they were only under 10,000 ft (where air is readily breathable and FAA doesn't require supplemental oxygen) about 30 seconds.
The question is could someone rendered unconscious from lack of oxygen and maintained in that state for 100 second revive to full awareness within about 30 seconds of roughly normal oxygen levels. It's conceivable, but I tend to doubt it. Joema 21:48, 28 January 2006 (UTC)

Technically, the O-rings did not shrink. They remained the same size but impinged on their metal interfaces with less force. Volume was constant, temperature and pressure decreased. Ah, such fine points are probably lost on the lay reader and the wording that the cold snap "shrunk the O-rings" is more accessible.

Explosion

I hope I didn't add too much tech talk to the lead paragraph, but I felt it was important to keep the lead para and the later "No explosion" paragraphs identical in content and meaning. Dobbs

The flame also severed the aft attach strut...

This line in the lead section seems out-of-place to me. "Severed" seems to suggest it cut it like a blowtorch rather than it failing under structural load. I suspect that the metal weakened upon heating and then collapsed under load. I chose the phrase "structural failure" specifically to avoid getting bogged down in those details: did the flame get to the struts? did it burn through to the wall of the central tank? My viewpoint is: in the lead paragraph, "it does not matter". Unless you know that it was exactly one, precise thing (and I am pretty sure that this was not the case), then do not waste the reader's time with the details.

In the lead section, the point should be that the crew died and it was a big setback for the American space program. For me, spending much time on the engineering details in the lead paragraph betrays a lack of recognizing what was historically Important in the disaster. -- Pinktulip 02:45, 19 January 2006 (UTC)

I chose the phrase "structural failure" specifically to avoid getting bogged down in those details: did the flame get to the struts?
Yes, if you read the Rogers Commission report (to which I included a footnote reference that you deleted), it's very clear the flame impinged on the aft SRB strut.
did it burn through to the wall of the central tank?
The flame impinged on the ET causing structural failure. There were burn marks on the ET debris showing that. The article never said it "burned through" the ET.
My viewpoint is: in the lead paragraph, "it does not matter". Unless you know that it was exactly one, precise thing (and I am pretty sure that this was not the case), then do not waste the reader's time with the details.
We know in detail the cause and failure sequence. It is documented in the Rogers Commission report, plus other NASA references.
In the lead section, the point should be that the crew died and it was a big setback for the American space program. For me, spending much time on the engineering details in the lead paragraph betrays a lack of recognizing what was historically Important in the disaster. -- Pinktulip 02:45, 19 January 2006 (UTC)
It's important to include the specific engineering details. The prime directive of an encyclopedia article is to factually describe the topic. Elaborating on social, political and historical factors is OK, but secondary to accurately describing the topic. You're right having a separate heading for technical details would be better, likewise having it later in the article is better. However having that information somewhere (even in the first section) is better than not having it. I just added a new section "Failure sequence", put the relevant details there.
I didn't do it before because it takes a lot of time to be thorough and do it right. You have to meticulously review information from various sources, which is quite laborious. Initially my highest priority was fixing gross errors in the article as previously written. Joema 16:30, 21 January 2006 (UTC)
I feel that, in the executive summary, the reader's tolerance for the details of the failure sequence is about two items: O-ring failure and the flame. Precisely what the flame did on a millisecond-by-millisecond basis can be done elsewhere. To the reader, by the time they see the flame, they know "Oooh. That is bad." and if it was not one thing to fail, then it would have been something else. Even if we know the detailed engineering blow-by-blow facts, we will just bog down the lead section with details if we try to get into it. The reader gets the important message: The super-hot flame was right there and then everything went klabooey and everybody died. If the O-ring had not failed, the disaster would have been avoided. In the lead section, that is all they need to know. -- Pinktulip 07:39, 25 January 2006 (UTC)

Vague sentence

At least some of the astronauts were alive and concious after the "explosion" because three of the four personal egress air packs (PEAPs) of the flight deck crew had been activated. The evidence indicates that the PEAPs were not activated due to the ocean surface impact.

Am I demonstrating poor reading comprehension, or is this paragraph contradictory? The first sentence says that three out of four were activated, and the last sentence says that they were not activated. --Bletch 03:37, 23 January 2006 (UTC)

The second sentence rules out one way of activation, not ruling out that they were activated in some other way--in fact, it appears intended to imply that they were activated by conscious efforts of the astronauts. Gene Nygaard 03:45, 23 January 2006 (UTC)

Ahhh I see now, what confused me is that the sentence can be intepreted either as:

  1. The evidence indicates that the PEAPs' activation was not due to the ocean surface impact.
  2. The evidence indicates that the PEAPs were not activated, due to the ocean surface impact.

In my case, I first interpreted the sentence as #2. I'd like to change the sentence to #1, unless there are any objections. --Bletch 03:52, 23 January 2006 (UTC)

You're right it could be worded better. Believe it or not the original wording (before the version you saw) was much worse. Joema 04:16, 23 January 2006 (UTC)
I reworded it. -- Pinktulip 07:28, 25 January 2006 (UTC)

Evacuation

Maybe I missed it, but can this article have a mini section on why the crew was unable to get out. If I recall, the Space Shuttle was bolted to its External Fuel Tank, meaning that it was unable to detach in an emergency. In addition, I don't believe the Challenger carried parachutes. Could someone who knows more about this please clarify? Palm_Dogg 21:42, 23 January 2006 (UTC)

They were strapped in their seats and there was no bailout nor ejection ability before the Challenger disaster. Also the orbiter could not separate from the external tank during powered flight. That would require various features which don't exist. E.g, powerful separation rockets. Even if that capability existed, the accident happened so fast it probably wouldn't have helped. There's some more information in the main Space Shuttle program article: Post-Challenger abort enhancements However you're right that's a natural question and should be added to this article. I try to do that. Joema 04:51, 24 January 2006 (UTC)
OK, added section Why crew escape was not possible
I renamed the section to simply "Crew escape was not possible". That way, the section makes an assertion. It seems obvious to me that the section should then explain why it makes the assertion. -- Pinktulip 07:26, 25 January 2006 (UTC)
Thanks. Palm_Dogg 23:21, 25 January 2006 (UTC)

Please reduce SRB section

The "Solid rocket boosters destroyed" deserves about two sentances in this article. As a matter of history, they are not very Imporant. I will wait a day or two for feedback/consensus. -- Pinktulip 07:24, 25 January 2006 (UTC)

You're right; I trimmed it way down. Joema 17:51, 25 January 2006 (UTC)

Five questions

  • If the crew was aware of the O-ring issue would it have been possible for the crew to detatch the orbiter, turn it around and land at KSC? —The preceding unsigned comment was added by 81.216.51.183 (talk • contribs) 15:37, 31 May 2006 (UTC).
No, the orbiter could not separate from the external tank during stage 1 (SRB) operation. A complicated sequence of steps is required for separation, and it doesn't happen fast. Post-Challenger, a "fast separation" option was added, but even that probably would not have worked, even had they known about the impending problem. "Fast" in this context means tens of seconds, not the sub-second separation seen in fighter plane ejections. Likewise the SRBs could not be jettisoned while burning. For more details see Space Shuttle abort modes. Joema 00:20, 1 June 2006 (UTC)
  • What happened first? Hydrogen tank rupture or the aft strut breaking? In the failure sequence, is one more important than the other? -- Pinktulip 07:56, 25 January 2006 (UTC)
  • What was the primary cause the aft strut failure: thermal or meachnical effects? -- Pinktulip 16:17, 25 January 2006 (UTC)
  • What "killed" the astronauts? It does not seem to me that the right SRB killed the astronauts. BTW: If the right SRB did not kill the astronauts, then I feel that it does not deserve a mention in the lead section. My point of view is that the reader wants to know what killed the crew, not what destroyed the Shuttle. Feedback? -- Pinktulip 07:56, 25 January 2006 (UTC)
  • Are there any of you who think that it was the imbalance in thrust between the two SRB's that was the primary reason that the Shuttle broke up? -- Pinktulip 16:17, 25 January 2006 (UTC)
Re what happened first, we don't know for certain whether the LH2 tank ruptured before the aft SRB strut broke, but it seems very likely. There's no instrumentation or photographic data to confirm merely the strut breaking, provided the SRB stays aligned with the stack. Once the SRB alignment diverges, the SRB on-board gyro package detected that and beamed back telemetry so indicating. However the telemetry is clear the LH2 tank ruptured significantly before the SRB alignment diverged. Since the entire stack depends on ET integrity, losing the ET was the initial primary structural failure. NASA said ET failure was possibly expedited by the SRB rotating inward and striking the intertank structure.
Re whether aft SRB strut failure was thermal or mechanical, we don't know for certain. If you heat an iron table leg, eventually it will fail from gravitational force, yet we consider the primary failure cause the heat, not gravity. Likewise the SRB attach strut was possibly weakened by the flame leak, and may have failed from flight loads. The data is clear the SRB alignment diverged well after the LH2 tank ruptured, therefore another possibility is the aft SRB strut failed because the ET structure it was attached to had already failed.
Re what killed the astronauts, the lead section clearly says they were killed upon crashing into the ocean. However the primary cause of the entire disaster was the SRB failure. If someone is killed by a gun, of course the ultimate cause is the bullet striking their body. But we generally describe them as being shot by a gun. Joema 17:31, 25 January 2006 (UTC)
Re was thrust imbalance between SRBs the cause of breakup; clearly not. Telemetry indicated the ET structural integrity failed first. The SRBs and SSMEs had sufficient steering authority to maintain controlled flight right until the disintegration. Joema 17:31, 25 January 2006 (UTC)

The foot-noters are back...

I am having the same problem with the 9/11 and the Terri Schiavo article. Footnotes do not belong in the lead section. If you have to footnote it, it is probably a piece of information enough to go in the lead section. The assertions you make in the lead section should be supported by the material in the other sections. The lead section is supposed to be only the chuncks of the story that are the most Important from a historical point of view. Are these guidelines really that unreasonable? I have no problems with footnotes elsewhere, but not in the lead section. A footnote in the lead section is, in my opinion, a symptom of a problem. It represents a lack of perspective on what is Important. -- Pinktulip 08:14, 25 January 2006 (UTC)

I've searched the Wikipedia style guides, and I don't see anything about not putting footnotes in the lead section. I've also searched external style guides and don't see it there, either. Did I miss something? Putting footnotes in the lead section is standard practice in formal reference papers. You can see than in virtually any literature. Joema 14:55, 25 January 2006 (UTC)
On this matter, I think that it is too much to expect Wikipedia to have a bunch of special guidelines for "complicated, historical events". I am hoping that common sense and journalistic judgement for this somewhat compex story would prevail. The SRB's take up more than two whole lines (and the distracting footnote) out of about 15 lines in the lead section. That is too much. They just are not that important. And you cannot explain them in five words or less, because they are complicated, so they just do not belong in the lead section at all. The SRB's (and I mean the whole SRB - I am aware that the O-rings are in the SRB's) did not cause the Shuttle to fail and did not kill the crew. They simply are not that interesting in this story. I cannot understand why you people are so obsessed with what happened to the SRB's after the O-ring failed. To the typical reader (even of above-averge intelligence), they are just hunks of the busted-up Shuttle. Not important. Not even interesting. Given such unimportant subject matter extra room decreases the overall quality of the article. -- Pinktulip 16:26, 25 January 2006 (UTC)
The SRB failure caused the disaster, destroyed the shuttle, and killed the crew. It is commonly so described. Their life functions terminated upon hitting the water, but that's secondary in the failure sequence. Readers will immediately want to know what caused the disaster. In keeping with journalistic "five Ws", it's important to briefly state the essentials in the first section.
Re "obsessed with what happened to the SRBs after the O-ring failed", I'm not, and there's very limited detail about that in the first section.
The SRB failure is the central physical cause of the entire disaster. Much of the Rogers commission investigation ultimately focused on that. Much of the news material of the time focused on that. SRB manufacturer Morton Thiokol had overall responsibility for the SRB failure, not the O-ring subcontractor.
Of course the failing SRB subcomponent was the O-ring, so it's described that way in the first paragraph. However the shuttle main component responsible for the overall physical failure is the SRB.
Imagine if an SSME nozzle burned through due to a ruptured cooling line, and a flame leak destroyed the shuttle. That almost happened in STS-93. If that happened it would have been described as an SSME failure, or an SSME failure due to cooling line rupture, or a flame leak from a failed SSME. Joema 17:23, 25 January 2006 (UTC)
The article is generally higher quality than other typical newspaper or encyclopedia articles. Examine the Encarta article on the same subject; this one is better overall. Another example: look at the difference between Aviation Week and typical newspaper coverage of any aviation or space incident. Newspaper and magazine coverage of those is frequently so poor it's laughable, primarily because of omitted detail, incorrect detail, and misplaced emphasis. I frequently read those, seeing paragraph after paragraph of eloquent descriptions about grieving relatives, etc, but no specifics about what happened. It's important to briefly state the essentials in the lead section, and include further detail in the article body. I agree extreme detail such as the RSO dialog was unecessary and could be reserved for an external reference. Joema 17:23, 25 January 2006 (UTC)

Keep the lead section BRIEF!

The lead section has just been doubled in size w/o any anything important. That is wasting the reader's time and decreasing the overall quality of the article.

In the lead section: DO NOT EXPLAIN THINGS! ESPECIALLY do not get into long, complicated Engineering explanations. Do not talk about complex vehicle failures. Just give the primary failures and then what happened to the PEOPLE; THAT is what the reader want to know.

Just state the most important, historical facts. That an event is televized sometimes matters, but o not spend more than one, short, sentance about such things. If the matter is complex, mention it only if it is of histoical significance and do not get bogged down in the details. That is what the other sections are for (if appropriate).

If you need this as a thought exercise: Imagine that the Shuttle was launched with robots rather than with the crew onboard and then it blew up. It would not have nearly the same, historical significance. The program would not have waited two years before trying again. That is part of the story. So my message is: Engineering-nerd-type: KEEP OUT of the lead section. People who only know what they see on TV: KEEP OUT of the lead section. We are trying to set prioriies in the lead section about what it Important. -- Pinktulip 12:51, 27 January 2006 (UTC)

I agree the lead section should be kept short, and the now-deleted long portion about relatively few people seeing it live was too much for the first section. As you said maybe one sentence for that point would suffice. It would have been nice to provide that instead of summarily deleting the entire portion.
I agree an unmanned shuttle failure wouldn't have the same human interest. However your point about an unmanned shuttle blowing up not causing a two year delay isn't really correct, and I wouldn't let that viewpoint guide your vision of what the article should be. When the unmanned Ariane 5 exploded on April 1996, the launcher was grounded for over 1.5 years. It was an embarrasment for Arianespace, and widely covered in the popular media. Loss of an unmanned shuttle would be even more impacting because unlike a production line launcher, a reusable vehicle is much more expensive, and making a new orbiter is problematic.
If you're producing a TV show or writing a novel, you mold that based on your perception of what your audience finds interesting. You want ratings. You don't want your audience getting bored. Consequently, pandering to the lowest common denominator is common for TV shows and novels. An encyclopedia article is totally different -- it's more similar to history textbook. You don't govern a history text by what you think people are interested in. There is a higher purpose, which is historical accuracy and completeness, independent of what you think people may want to read.
In keeping with the journalistic "five Ws" it's important to state the specific essentials in the lead section, but not be excessively verbose. Those should be stated regardless of whether some readers find it boring or uninteresting. This article as currently written is not perfect, but it essentially accomplishes that. Joema 17:49, 27 January 2006 (UTC)

How many saw it live on TV?

Do not discuss the veracity of our own assertion in the article! Talk about it here on the TALK page.

OK. You disagree with the statement that "millions" saw the disaster live on TV. What number would you be happy with? Hundreds of thousands? Tens of thouseands? This was a special launch because the teacher was on board. This was an important historical event. Try to find the facts and the words to express this briefly.

One other thing: Never use the word "actually". That word is a signal that you are about to go off into a lecture about some trivia. The article is here for Brilliant Prose were you make specific, clear assertions. -- Pinktulip 13:02, 27 January 2006 (UTC)

OK. I have taken this input into accord with a minor rewording of the second paragraph of the lead section. See how that works? It only take a few words (and no capitalization) to take these concerns into account. -- Pinktulip 13:21, 27 January 2006 (UTC)

It is too bad that we did not notice that tomorrow is the 20th anniversay of the disaster. This could have been a killer featured article. -- Pinktulip 13:37, 27 January 2006 (UTC)

Tell me about it. I nominated the picture of Challenger disintegrating as a Featured picture candidate and am only belatedly pushing for it to go on the main page under anniversaries. If anyone has any brilliant ideas, now's the time to say something. Palm_Dogg 06:08, 28 January 2006 (UTC)

I was sitting in a kindergarten classroom watching it live as part of NASA's satellite broadcast. Has to do interesting things to your mind when you're 4 1/2 years old and you idolize astronauts and schoolteachers. Ashmedai 20:12, 27 January 2006 (UTC)

I do believe that millions viewed the space shuttle disaster. I dare say every school in America was watching, because of the first teacher on board. I was in the 7th grade. I still tear up when the subject is brought up. Millions of children, nation wide, watched people die live. We learned everything about Christa McAuliffe, because she was a teacher. We felt we new her, and cheered her on. When the shuttle exploded, there was dead silence. Then when we realized what happened, we cried, the staffs cried,but then no one talked about what we viewed. Do people think that did not effect us in some way? There are kids who didn't grasp what happened, but most did. No one offered counceling to anyone. No one discussed the effect on America's children. Not that I have heard. It is something that should have been addressed. Thank You. Shawna Turner

Jettison the SRBs?

The 'Plume' section says that even had Houston or Challenger known about the SRB situation ~1 minute after liftoff, they couldn't have done anything. Couldn't they have jettisoned the boosters immediately and kept burning the main engines to gain altitude, then attempt an emergency landing? Risky, but a darn sight better than what ended up happening.

The SRB plumes would destroy the orbiter.
Three problems: (1) As stated above SRB plumes an issue. Whether they'd destroy the orbiter is unclear -- depends on departure angle, but it's quite likely they'd significantly damage it. (2) Vehicle was near Max Q (max aerodynamic load). Minus the SRB thrust, there'd be tremendous deceleration from atmospheric drag, as the SSME thrust is small relative to SRBs. This would essentially throw the orbiter forward, shearing off the orbiter/ET attach struts. Orbiter would pitch or yaw into the windstream, breaking up similar to the actual accident. (3) At T+60 (roughly onset of major Challenger SRB problems), minus SRB thrust, orbiter/ET thrust-to-weight ratio is way below 1:1. The orbiter/ET would essentially fall out of the sky, even if the SRBs were successfully jettisoned.
You could modify the SRBs for bigger lateral jettison motors, possibly fixing or lessening the plume problem. You could beef up the orbiter/ET attach struts to not shear off after SRB jettison near Max Q. However you can't change the orbiter/ET thrust-to-weight ratio at T+60 -- it would still fall to the ocean. Before Challenger there was no bailout and ocean ditching isn't survivable, so even if you could jettison the SRBs, then separate the orbiter and ET, it's futile. Post-Challenger, bailout is available, but orbiter/ET separation near Max Q likely isn't possible. Aerodynamic forces would make the ET "recontact" the orbiter after separation, destroying both. Joema 14:58, 29 January 2006 (UTC)

How high was it?

Can someone tell me how high above earth the shuttle was when it "disintegrated"?–Clpalmore

About 46,000 feet (14,020 meters). Joema 14:59, 29 January 2006 (UTC)
Thanks–Clpalmore

Remains of the Challenger crew

Maybe I missed it, but I didn't see anything of great detail in this article about the remains of the Challenger crew. Aren't the remains all buried together in a grave at Arlington because they were not able to identify them individually? I think maybe something should be said in the article about that. I could add a little something about this, if no one objects, or someone who knows a good bit about the Challenger disaster could do it. Either way would work. --WikiFiend90 01:20, 29 January 2006 (UTC)

Very few details are available. NASA intentionally did not release specific information on this area. Joema 15:00, 29 January 2006 (UTC)
  • I was able to find a page on the Arlington National Cemetery website dedicated to the memorial there for the Challenger crew. It says: "On April 29, 1986 the identified remains that had been located were turned over to their families for burial. However, there were number of unidentified remains. These remains were buried at Arlington National Cemetery on May 20, 1986, beneath the Memorial that appears below. Two of the crewmembers, Scobee and Smith, were buried in Arlington National Cemetery as well." So I admit I was halfway wrong about the remains, but I do still think this should be mentioned in the article. (I'm not trying to sound bossy or mean with that last comment, hehe.) Anyway, like I said, if no one minds, I'll be more than happy to put in a little something about this. -WikiFiend90 05:44, 1 February 2006 (UTC)
Sorry, I thought you meant remains inside the vehicle. Re the cemetary, go ahead and add something if you want. Please be tactful when adding info about this sensitive area. Add a link to the Arlington site if readers want more info. Joema 06:07, 1 February 2006 (UTC)
If you must, add a section or sub-section to the main body of the article. I do not think that such info should be added into the lead section. It is not that Important relative to the other facts already asserted about the disaster in the lead section. -- Pinktulip 12:44, 1 February 2006 (UTC)
Yes, absolutely. Joema 15:05, 1 February 2006 (UTC)
  • Exactly. Another section or sub-section was just what I had in mind. I didn't want to add it to the lead section, like you said, as it obviously isn't as relative to everything else in the lead section. I will also add a link, which I had planned to do anyway. I just wanted to make sure no one objected to me adding a little something. -WikiFiend90 18:59, 1 February 2006 (UTC)
OK, I added a section on the remains, and kept it as brief and as tactful as possible. I also added a picture and I added the link to the Arlington page in with the external links. I hope it's looked at as a job well done. :-) -WikiFiend90 19:51, 1 February 2006 (UTC)

Citations & Infobox

http://www.hq.nasa.gov/office/pao/History/sts51l.html

For any interested parties (And because this page needs A LOT!). Palm_Dogg 05:13, 2 February 2006 (UTC)

P.S. Also replaced the bulky table with an Infobox. A cursory scan of other Space articles suggests that tables are in use there as well. Rather than take the time to set all those up, wouldn't it be easier to just modify the Infobox? Palm_Dogg 08:14, 2 February 2006 (UTC)

Same info is already pointed to by the link http://history.nasa.gov/sts51l.html . I am assuming that the infobox is more standard, even though the articles for the previous and next missions (STS-61-C and STS-26) do not yet use that infobox. Thanks. -- Pinktulip 08:30, 2 February 2006 (UTC)

Tribute/Burial section should use tables

The Tribute and Burial section to use HTML tables to ensure that the text of other sections does not flow into or otherwise intrude on these two particular sections. Go ahead and fill in the white space with excess, honorific verbiage, if you can find something appropriate. As far as I am concerned, whitespace is not a problem. -- Pinktulip 17:13, 2 February 2006 (UTC)

I decided to write it as "The rest were buried together..." as if to suggest that, in a sense, the crew rests together at the Memorial site. It does not scan as well as I would like it to, but it is an attempt to acknowledge the humanity of the remains at the Memorial. I think that what is important in this case is that our words match the images on the bronze plaque of the Memorial. -- 17:37, 2 February 2006 (UTC)

Peer review?

I feel like we should push to tidy up those red links with a bunch of somewhat stubby pages or something. -- Pinktulip 03:54, 6 February 2006 (UTC)

You're right. I linked a few red ones to now-exising articles, de-linked some red ones that aren't particularly relevant, and left some red which probably need articles. I'll try to write some stub articles for those if I have time. Joema 19:22, 6 February 2006 (UTC)
Working on adding the stub articles. Harder than I first thought since some existing stubs require editing to a common format, plus have errors requiring correction. Joema 16:54, 7 February 2006 (UTC)
Stub articles now mostly complete for each flight control position mentioned in this article. Joema 18:33, 9 February 2006 (UTC)

No tables, I guess

I did not start this use of HTML tables, but someone removed them today. OK. No tables, but please gather ther honorary things together and keep them "clean" from nerdy, grungy "dirty" stuff like "debris". It helps to emphasize the solemnity of the tributes and burials. The investigation fits in OK as well only because it is "Presidential". The two photos might create a narrow column of text in the middle. Is that OK with everybody? -- Pinktulip 17:50, 7 February 2006 (UTC)

Sigh. OK, have it your way. I just wanted it to be honorific because of the solemnity of the memorials. I am here watching Coretta Scott King's funeral and it is all honorific stuff. Clean. Separate. -- Pinktulip 19:08, 7 February 2006 (UTC)

Changes to first section

Reduced word count in first section. Moved/added info describing exact failure cause to new section toward article end. Joema 01:52, 8 February 2006 (UTC)

Thanks for wikify to "Teachers"

"Teachers in Space" is the correct term. I was wrong to assume that "civlian" implied non-aviator. I just talked with an AMES engineer who straightened me out on that. AWM -- 68.164.245.60 21:32, 24 February 2006 (UTC)

Resnik's "hot" comment

I removed the statement added by 24.238.207.232 that Renik's "(expletive) hot" statement at T+15.0 sec referred to SRBs producing more than expected thrust. I can't find any clear basis for this. We normally don't add statements based merely on speculation. If you have specific information otherwise, let's discuss. Joema 23:34, 27 February 2006 (UTC)

Can I delete my own stuff?

I appreciate your technical comments. However to my knowledge NASA has never mentioned what Resnik's statement might mean. It's possible it might refer to SRB performance, but we don't know. That phrase is also a very common exuberant expression.
SRB thrust and burn time is temperature dependent. Higher ambient temperatures produce greater thrust and less burn time. Lower ambient temperatures cause less thrust and greater burn time. STS-51L was launched in by far the coldest weather of any mission. Therefore SRB thrust could not possibly have been above normal for other missions.
However, if you normalize other mission's SRB performance to STS-51L environmental conditions (IOW mathematically adjust their SRB performance downward based on predicted lower performance at the STS-51L temperatures), by comparison the 51L SRB chamber pressure was slightly higher (about 1.3%) than the adjusted arithmetic mean of the other missions, but it was well within expected limits: [5].
According the Rogers Commission report, the crew has essentially no cockpit indication of SRB performance: "The only information with regard to SRB chamber pressure available to the crew is a message "Pc < 50" (indicating both SRB chamber pressures less than 50 psi) on a cathode-ray tube (CRT) display, which indicates SRB burnout and that SRB separation is imminent." [6]
Regarding your statement that SSME throttle profiles were adjusted at T+17-20 seconds or earlier, that clearly did not happen on STS-51L. The Rogers Commission documents include a graph of SSME throttle commands for that mission, and it shows no throttle down command until about T+28 sec: [7]. Note: chart x-axis is GMT, not Mission Elapsed Time (MET). SRB ignition was at 28:16:38:00.010. Each fine tick mark is 1 second.
Based on the above there's no substantial basis for assuming Resnik's expression referred to SRB performance. It might have been, but this is an encyclopedia, not Usenet. If you want to state that on sci.space.shuttle, that's fine. However we don't put speculation stated as unqualified fact in encyclopedia articles, even if it may seem plausible.
If after considering the above, you have a specific NASA statement about Resnik's expression, describe that and we can discuss further. Otherwise the speculative statement should be removed.
BTW you're not supposed to delete someone else's comments from your own talk page, much less an article talk page. I restored my comments which you deleted. Joema 17:30, 28 February 2006 (UTC)


Ok, incorrect speculation removed.

Thanks for the cooperation. If you ever find anything substantive about the Resnik statement, let's discuss further. You obviously have a lot of technical knowledge about the shuttle, so please contribute further. There are numerous articles on aerospace subjects in need of expert help. Re deleting your own statements, in general the talk page should remain a record of the discussion, but I don't think there's a hard rule against deleting your own stuff. See Wikipedia:Etiquette and Wikipedia:Talk page guidelines. Note due to the version-based history system, you can't totally delete it -- people can always just press the "history" tab and see what you wrote. Joema 01:02, 1 March 2006 (UTC)

Picture

Moved the picture to get rid of the gap it caused. If everyone hates it, move it back. Dark jedi requiem 03:26, 3 March 2006 (UTC)

Reversion of changes to failure scenario in first section

First thanks to User:199.46.245.232 for the changes to the failure scenario in the first section. However for several reasons I had to revert it. Main part of change read:

The leak also caused a loss of thrust in the right SRB, and the Space Shuttle guidance system attempted to compensate by radically moving the Shuttle control surfaces. This placed overload stresses on one of the SRB connecting struts which failed. The SRB then pivoted about the remaining strut, and impacted the external fuel tank resulting in a rupture. Within seconds the flame and and the pivoting SRB..., and the edit comment was: "Elaborated on cause of SRB seal failure, and cause of external tank rupture - Source of info: Aviation Week and Space Technology, circa Feb 7, 1986)"

Reasons for reversion:

  • The shuttle does not use control surface (elevons) steering during ascent, hence the entire reasoning about that isn't correct. Rather the control surfaces follow a fixed position schedule to minimize aerodynamic bending loads on the wings. Ascent steering is solely by SRB and SSME gimbaling. The elevon position/time graph can be seen in the CAIB report, Vol II, Appendix D.8, figure 2-3:(15.8 MB .pdf): [8]
  • The SRB causing ET rupture by itself isn't really correct. According to the Rogers report, the ET aft end failed and SRB pivoting into the intertank structure happened at about the same time. The failure cause was these two approximately concurrent events. These events resulted in the ultimate physical cause of the breakup: the ET disintegrating, which was the structural backbone of the entire stack. That in turn placed the orbiter off-axis into the windstream, causing destruction by aerodynamic loads. For details, see the Rogers Commission report, chapter 3, at [9]
  • In general we want the first section of any article to be somewhat concise. The detailed failure sequence is later in the article, along with the exact timeline.

Let me know if any questions. Joema 17:01, 23 March 2006 (UTC)

Reversion of "defining moment" sentence in 1st section and Jay Greene removal

Removed sentence: "The Challenger disaster remains one of the defining moments of the 20th century." Reason: while phrase is often used in popular media: newspapers, magazines, editorials, etc, it's not really encyclopedic in tone or function. As encyclopedia writers, we don't make judgements about what is or isn't a defining moment. What is a defining moment varies based on background and perspective. For some it was Apollo 11. For others it was the Japanese American internment. If every major headline news event is tagged as a "defining moment", thousands of articles will be so referenced. Let me know if any questions.

Re Jay Greene, he was the flight controller for STS-51-L, so his name and title should remain under the mission control personnel list. True his name is redundantly listed on a picture caption, but it doesn't state his title, and adding his title to that caption means everybody's title should be added. Joema 18:18, 11 April 2006 (UTC)

"Featured Article" page has an error

The featured article on the english main page says "Because shuttle launches had become almost routine after fifty successful missions......" I'm not sure if this is correct. The Challenger disaster actually occured on STS-25. Were there 25 test launches before an actual mission took place??? I believe it should be 25 instead of 50. 68.187.192.107 04:18, 21 May 2006 (UTC) --Absolutly correct, this is a mistake. STS-51L was the 25 flight, and I know that there were no test launches because STS-1 was the first (and only, as of 07/06/06) time an untested spacecraft has flown a manned flight. --GW_Simulations|User Page | Talk | Contribs | E-mail 18:17, 7 June 2006 (UTC)

Split

My reccomendation is to split it into a page about the mission (STS-51-L), and a page about the disaster (here), in the same way that STS-107 and Space Shuttle Columbia disaster are seperate. --GW_Simulations|User Page | Talk | Contribs | E-mail 14:00, 4 June 2006 (UTC)

I agree.
Columbia completed it's mission, Challenger did not. The reader will have to jump around to get a little information about what was going to happen which was never completed. Boringguy 08:20, 9 June 2006 (UTC)
I have made a first attempt at the split. The "mission" page is weak and we need to add a bio of each of the crew, at least to the "disaster" page. --67.121.113.141 20:23, 15 June 2006 (UTC)
Done. How is that? -- 67.121.113.141 21:57, 15 June 2006 (UTC)
Most of the changes you made are good, e.g, deleting Resnik comment. However the post-breakup dialog should remain. It is among the most historic and best known aspects of the disaster, e.g, "obviously a major malfunction....vehicle exploded", etc. Joema 22:59, 15 June 2006 (UTC)
Sorry. I should have mentioned it here. Space Shuttle Challenger disaster#Post-breakup flight controller dialog restored. -- 67.121.113.141 00:11, 16 June 2006 (UTC)

Question

Shouldn't this read "deceleration"?

The crew cabin impacted the ocean surface at roughly 207 miles per hour (333 km/hour), causing acceleration of over 200 g, far beyond the structural limits of the crew compartment or crew survivability levels[2].

•Jim62sch• 00:50, 8 June 2006 (UTC)

From an engineering point of view, it is all acceleration. When one uses the term "deceleartion", it is often understood to mean "controlled decelleration" (as in a self-propelled vehicle doing some braking), which this was not. -- 67.121.113.141 22:25, 15 June 2006 (UTC)

Image names?

It is distracting that some of the image names start with "STS-33", which seems wrong. -- 67.121.113.141 18:59, 16 June 2006 (UTC)

The mission was officially desinated STS-33. See CAIB Report Chapter 8, Page 203 (page 107 in the PDF) at the bottom right of the page. Missions after Challenger are often desinated with the letter 'R' to mean a reuse of the desination. See this link for a list that shows the official numbering system and "anti STS-13" numbering system. Boringguy 12:40, 19 June 2006 (UTC)

Automated peer review

I used AndyZ's peerreview.js tool on this page to create its generic output. We should try to conform to it as much as practicable. -- 67.116.253.187 19:46, 28 June 2006 (UTC)

inline references

I inlined the references. The last three were books that are not actually cited in the text so I changed them into a book list. -- 75.26.2.209 18:32, 30 June 2006 (UTC)

Florida License Plate

Is anyone interested in adding information about the specialty license plate here in Florida whose proceeds go to some relevant charity? They are still being made almost 20 years later. 207.203.80.14 17:28, 6 July 2006 (UTC)

Details of the SRB failure

Greetings! Would it not be informative and usefull to add a description of how the failure progressed, specifically, why it took 73 seconds for the field joint to fail? The puffs of smoke in the photos we've all seen indicate the 0-rings being vaporized at SRB ignition. This would have been lethal if not for the fact that the charred residue in effect "plugged" the gap, preventing the exhaust gases from escaping. It is a fact that Challenger encountered the worst wind shear recorded for a shuttle flight, around the time the shuttle passed through Max-Q, which caused the psudeo-seal to be knocked loose, at which time the flame plume exiting the right SRB was seen. You guys let me know what you think, I can write that portion and submit it for review. Thanks! --TheMadCap 21:55, 17 July 2006 (UTC)TheMadCap

'T+' times

I think this article is really good, but found a bit sloppy the way times after liftoff are dealt with. Section Liftoff is the first one to mention times in the 'T+' format, but the explanation that "Times are given in seconds after launch" is given only in the next section. This may not be obvious from the start to all readers. Then, statements such as "The last view of smoke around the strut was at T+3.375" are a bit puzzling. Events like a view of smoke surely last some time - why then mention such a precise time when it's not explained whether it means the start or the end of the event, as detected by a piece of equipment? If that is unknown, then it would make greater sense to simply say "around T+3". Finally, expressions like "After the orbiter and external tank disintegrated at about T+73.213" are just pointless. If the exact time is unknown, then why give as reference a time precise to the millisecond? It should read simply "at about T+73". In other words, there seems to be an overly extensive use of very precise times, probably with the aim of reinforcing the accurate nature of the article but really producing the opposite effect... Telmo Amaral 23:59, 21 July 2006 (UTC)

The T+ times are listed verbatim from the Presidential Commission report: http://www.challenger.org/about/assets/nasa_report.pdf. You're right the T+ format should be described early on. Re why say "about T+73.213", that's the telemetry timecode from the closest instrumented event to the described event. You're right in this one case we might could say T+73. However in other similar cases, the Commission report itself uses millisecond precision. The safest decision is always to convey exactly the timecode from the original report, not make changes. Joema 04:10, 22 July 2006 (UTC)
Thank you for your explanation, Joema. I took the liberty of removing the sentence "Times are given in seconds after launch" from section 'Initial ascent', where it seemed belated. Then, I inserted the sentence "All times are given in seconds after launch and correspond to the telemetry time-codes from the closest instrumented event to each described event" at the end of section 'Liftoff', that is, after the first usages of the 'T+' notation. I think the reference to "telemetry time-codes" can be clarifying for readers not familiar with the Presidential Commission's report.Telmo Amaral 00:05, 28 July 2006 (UTC)

Probably controversial addition

Having just read an article preserved by Allen Lutins,[10] I'm thinking of adding a bit more about the astronauts' deaths and NASA's initial reluctance to release any information about the disaster. When I get worked out exactly how I want to word it, I'll put it up here for discussion. --ChrisWinter 23:09, 26 July 2006 (UTC)

To what end? I am not sure it is necessary to include vivid details from that particuar article. Perhaps a link to the article so people can view it if they wish? I do not see how that piece and the horrifying details of the recovery of our astronauts improves this page.
It does read a lot like a hit piece, I admit. Still, I think it makes some points worth mentioning. One would be that NASA's clinging to the assumption that the crew cabin broke up in midair hampered the investigation. OTOH, it could be argued that it was kinder to let the sea have its way with the bodies than to bring them up when they still looked like people. (And for the record, I wasn't planning to include "horrifying details".) --ChrisWinter 14:53, 27 July 2006 (UTC)
I believe the fact that NASA was not as forthcoming with the information intially after the disaster was likely due to the fact that they didn't know what had truly happened. I think they believed it was best to have a clear idea of the event before making any statements that could be interpreted as being incorrect later. And they certainly would not have commented on the astronauts themselves out of respect for the families. --TheMadCap 13:14, 27 July 2006 (UTC)
I would disagree with some of that. But clearly I need to think more about changing the article before going ahead. Perhaps what's needed is a separate article about controversies related to the disaster. --ChrisWinter 14:53, 27 July 2006 (UTC)
After reconsidering, I suspect you may be correct about NASA's motives, but in reality, their hands were pretty much tied. After all, they couldn't very well tell the entire world that the astronauts suffered a long, painfull, horrifying death complete with the details. But I take your point nevertheless.
Personally, I have ZERO doubt that impact with the ocean killed the seven astronauts and that they were awake and aware at least initially after the crew cabin was ripped from the airframe. I have spoken with certain persons who claim to have heard the contents of the personal recorder worn by one astronaut that contains "one very sad occurance". Personally, I don't think I would like to hear what that tape contains.
As far as a separate article with controversies dealing with the disaster, I have no problem with that at all. In fact, I could help add some material to that, as I have done a great deal of research into this tragic event myself. --TheMadCap 17:51, 27 July 2006 (UTC)
My feeling is that including much more information about the astronauts' deaths (and the investigation into this aspect of the accident) would unbalance the article. When I look at the length of the section on the astronauts' deaths and compare it to, say, the section on the causes of the accident, it seems to me that making the former any longer would be disproportionate. --MLilburne 09:50, 28 July 2006 (UTC)
MLilburne is right -- article section lengths should remain balanced on the overall disaster. Adding any more info on the astronaut deaths would unbalance it. Also, nobody knows for sure the exact details of their deaths. You can speculate on that all you want on Usenet or other discussion forums, but an encyclopedia article is not the place for that. This has nothing to do with not offending astronaut families, etc, but the simple fact that we don't know. We're encyclopedia editors, we don't originate new information or theories. We emphasize the "party line", which in this case is the Kerwin report that describes the astronaut death. That report states "the crew possibly, but not certainly, lost consciousness in the seconds following orbiter breakup due to in-flight loss of crew module pressure". There are many examples of rapid pressure loss for military and civillian aircraft. Above 50k feet altitude, rapid pressure loss can stun and disorient, giving only several seconds useful consciousness before hypoxia takes over. FAA regulations require either pilot or copilot on commercial airlines to wear oxygen masks full time when flying above 41k feet. Why? Because rapid pressure loss would knock them out before they could even don the masks. These well-known facts likely impacted the Kerwin report wording. Joema 23:27, 28 July 2006 (UTC)

Controversy #1

This paragraph from the article (slightly reworded by me) is IMO controversial for two reasons.

In hindsight it is clear that the field joint was inadequately designed, but likely would not have caused a fatal problem if Challenger had launched under normal Florida temperatures (over 50 °F or 10 °C). The abnormally low temperatures of her last mission, combined with the inadequate joint design, produced a seal failure. Engineers at SRB manufacturer Morton Thiokol were aware of the problem and warned against launching, but the warning did not reach NASA management.[citation needed]

First, this is the first place in the article where it is mentioned that ambient temperatures were unusually low on launch day. Second, it is recorded that SRB field joints had leaked before, even during launches in warmer weather. I'll try to find citations. --ChrisWinter 02:01, 27 July 2006 (UTC)

Citations both for the previous low temperatures and the previous SRB problems can both be found in the Diane Vaughan book that's listed in the References section (I can get page numbers if you want them). The statement that it's "likely" the accident wouldn't have happened if it was warmer sounds a bit more like interpretation, but I think it's defensible. There's probably a citation for that somewhere too, in Vaughan or in the Rogers Report.
To be honest I'm more worried about the last sentence you quoted. It's clear from Vaughan and Rogers that the warning did reach NASA management, just didn't work its way as far up the hierarchy as it should have. So I'm thinking about rephrasing that. --MLilburne 08:39, 27 July 2006 (UTC)
Use the Rogers Commision report for citations. There is an entire section dedicated to preserving the testimony of witnesses from both NASA and Thiokol which deal directly with temperature issues, and the attempt to stop the flight the night before during the meeting with NASA and Thiokol. --TheMadCap 13:07, 27 July 2006 (UTC)
I changed the wording here to reflect that there was communication of the problem but it was not considered compelling enough for NASA to change its mind. The Tufte book chapter mentioned in "Further Reading" gives an extraordinary account of how poorly communicated the O-ring issue was. It was referenced pretty well too, including the Commission Report on several instances. Baccyak4H 20:12, 17 August 2006 (UTC)
Thanks for the proofread MLilburne. Baccyak4H 13:57, 18 August 2006 (UTC)
Any time! I'm still thinking of doing a bit more work on this section, but you've definitely improved it. MLilburne 14:02, 18 August 2006 (UTC)

In 1989, Aerospace and Defense Science Magazine did a 4 part series on the *real* cause of STS 51-L failure. I lost these issues, and cannot find Mr. Bob DaCosta in Florida anymore.

If anyone can help me, please post. Let us just say this is how the Wiki article *should* begin:

The failure of STS 51-L Challenger was due to a structural design defect: Connecting strut "P-12" between the R-SRB and ET was exposed to torsional stresses *pre* launch 4 times what the assembly was designed to withstand.

Initial root cause failure was at T-3 seconds. Extensive anaylsis and investigation found that, while possible, the "O-rings" had nothing to due with the loss of the vehicle and crew. The failure was designated fundemental since the basic STS stack configuration is *a* symmetrical.

I also ask anyone who still believes the Rogers Commission Report to try this simple experiment: Wad up a marble sized ball of ordinary plumber's putty, and put it in your kitchen sink tap. Now turn on the cold water. Obviously, the putty could not hold 75 psi cold water for even 1 second. The Report, however, claims that this same ordinary plumber's putty held - get this one - 900 psi, 5,700 degrees F thermite reaction exhaust for 55 seconds.

I also point to you Dr. Richard Feynman's book "What Do You Care What People Think?" where he recorded the analysis by the same JPL engineers who literally invented the SRB: "few seconds - big explosion". In May, 1986, a launch of a Titan rocket from VAFB failed due to booster side wall burn through - at the predicted T+7 second time. Finally, as bad as my memory is, Mr. Boisjoly confirmed in his testimony to Dr. Feynman during the Commission hearings that the "O"-ring blow by would cause a catastrophic failure - during the first 1/3 second *or not at all*

On a personal note, my co worker, Greg Jarvis, was on STS 51-L. We owe it to him and all the brave astronauts to be sure that all design defects are corrected. For example, CCAFB personel examined the LP after 51-L. They found chunks of ET orange foam all over the place. Thus, the failure of STS Columbia in 2003 was also a preventable tragedy. I urge the re use of the white, rubbery paint coating on the ET that was used during the first 3 flights. This will contain the debris which has been observed on every flight.

      • REPLY BY THEMADCAP: Very interesting, but can it be proved? I cannot find any reference to the periodical you refer to. Has it been renamed? The last reference to a Robert Decosta was to attend a funeral in Cocco, FLA in 1999. Please provide more information, as you have peeked my interest.

It is interesting that you mention that particuar strut, as NASA recently announced that the stack was having issues with unacceptable loads on that very structure. In fact, STS-114 launched under LowQ to releave this type of stress, and I heard it mentioned by some engineers at KSC that a LOV/LOC could occur from this issue.

With regards to Fire retardant Latex coating on the ET, this might help a bit, but even on STS-1 and 2 there was foam liberation. Foam shedding is impossible to eliminate without a redesign of the entire shuttle stack, and that simply, is not going to happen. Even though its removal saved only about 595 pounds from the lift-off weight, I believe the added fuel required may interfere with the shuttle fleets' capacity to haul ISS parts to orbit. --70.105.6.234 00:46, 28 August 2006 (UTC)***