Challenger Explosion

[Stiffler]

Kinda a new view of the tragedy

Here it is

[Guest bravodelta79]

And another... the backup teacher who would have gone had the one who did not been able to go. You don't see the shuttle, but you see her reaction.

http://www.youtube.com/watch?v=Git1nrTAg5w

[JarheadBoom]

Still remember that day; watched the launch at school in a big assembly. Teachers were so upset throughout the entire school district, that they ended up sending us home early.

I still cringe thinking about what that 2+ minute freefall must have been like for the crewmembers who survived the explosion.

[Guest C-21 Pilot]

Still remember that day; watched the launch at school in a big assembly. Teachers were so upset throughout the entire school district, that they ended up sending us home early.

I still cringe thinking about what that 2+ minute freefall must have been like for the crewmembers who survived the explosion.

I was in 4th grade...remember it like it was yesterday.....just like 9-11, etc.

BTW, I don't think it would be possible for anyone to survive that - probably incinerated w/ the shuttle (at least I hope so).

[HossHarris]

I was in 4th grade...remember it like it was yesterday.....just like 9-11, etc.

BTW, I don't think it would be possible for anyone to survive that - probably incinerated w/ the shuttle (at least I hope so).

Talk to your safety shop guys to get the report from safety school. IIRC, a few of the astronauts actually drowned.

[usaf36031]

I had no idea that they didn't all disintegrate in the explosion, but a google search indicates that after the explosion a few (at least) did remain conscious for at least a few seconds (long enough to activate their emergency air packs) before the remains of the shuttle fell over 65,000 feet to the ocean, where the bodies remained submerged for weeks before being recovered. If the cabin depressurized at that altitude however, it is unlikely in my opinion that any remained conscious for more than a few seconds. Very sad stuff.

[JarheadBoom]

If the cabin depressurized at that altitude however, it is unlikely in my opinion that any remained conscious for more than a few seconds. Very sad stuff.

From first launch to this day, Shuttle crews wear full pressure suits until established in orbit. Cabin depress isn't a factor.

IIRC, a few of the astronauts actually drowned.

I recall that coming out of the investigation as well.

****** EDIT ******

My curiosity was piqued after posting this and thinking about it some more, so I did a little more Google-ing. Too much info to post, so here's some links. Be advised - all but one are not official:

Challenger crew survival?

Snopes on Challenger crew "transcripts"

MSNBC article (part of a series)

Related - Columbia crew survival

Arlington National Cemetary memorial page - part of the official report located about halfway down the page

NASA's Challenger page

more editing...

usaf36031 - right you are about the pressure suits. Apparently Challenger's crew was wearing standard NASA blue flightsuits (NOT pressurized), with a sealed helmet that delivered oxygen in case of cabin depress.

[usaf36031]

From first launch to this day, Shuttle crews wear full pressure suits until established in orbit. Cabin depress isn't a factor.

False. pressure suits and parachutes weren't added until the first launch following the Challenger disaster.

I found the following transcript during my google search.

On July 28, 1986 Rear Admiral Richard H. Truly, NASA's Associate Administrator for Space Flight and a former astronaut, released this report from Joseph P. Kerwin, biomedical specialist from the Johnson Space Center in Houston, Texas, relating to the deaths of the astronauts in the Challenger accident. Dr. Kerwin had been commissioned to undertake this study soon after the accident on January 28, 1986. A copy of this report is available in the NASA Historical Reference Collection, Hstory Office, NASA Headquarters, Washington, DC.]

RADM Richard H. Truly

Associate Administrator for Space Flight

NASA Headquarters

Code M

Washington, DC 20546

Dear Admiral Truly:

The search for wreckage of the Challenger crew cabin has been completed. A team of engineers and scientists has analyzed the wreckage and all other available evidence in an attempt to determine the cause of death of the Challenger crew. This letter is to report to you on the results of this effort. The findings are inconclusive. The impact of the crew compartment with the ocean surface was so violent that evidence of damage occurring in the seconds which followed the explosion was masked. Our final conclusions are:

the cause of death of the Challenger astronauts cannot be positively determined;

the forces to which the crew were exposed during Orbiter breakup were probably not sufficient to cause death or serious injury; and

the crew possibly, but not certainly, lost consciousness in the seconds following Orbiter breakup due to in-flight loss of crew module pressure.

Our inspection and analyses revealed certain facts which support the above conclusions, and these are related below: The forces on the Orbiter at breakup were probably too low to cause death or serious injury to the crew but were sufficient to separate the crew compartment from the forward fuselage, cargo bay, nose cone, and forward reaction control compartment. The forces applied to the Orbiter to cause such destruction clearly exceed its design limits. The data available to estimate the magnitude and direction of these forces included ground photographs and measurements from onboard accelerometers, which were lost two-tenths of a second after vehicle breakup.

Two independent assessments of these data produced very similar estimates. The largest acceleration pulse occurred as the Orbiter forward fuselage separated and was rapidly pushed away from the external tank. It then pitched nose-down and was decelerated rapidly by aerodynamic forces. There are uncertainties in our analysis; the actual breakup is not visible on photographs because the Orbiter was hidden by the gaseous cloud surrounding the external tank. The range of most probable maximum accelerations is from 12 to 20 G's in the vertical axis. These accelerations were quite brief. In two seconds, they were below four G's; in less than ten seconds, the crew compartment was essentially in free fall. Medical analysis indicates that these accelerations are survivable, and that the probability of major injury to crew members is low.

After vehicle breakup, the crew compartment continued its upward trajectory, peaking at an altitude of 65,000 feet approximately 25 seconds after breakup. It then descended striking the ocean surface about two minutes and forty-five seconds after breakup at a velocity of about 207 miles per hour. The forces imposed by this impact approximated 200 G's, far in excess of the structural limits of the crew compartment or crew survivability levels.

The separation of the crew compartment deprived the crew of Orbiter-supplied oxygen, except for a few seconds supply in the lines. Each crew member's helmet was also connected to a personal egress air pack (PEAP) containing an emergency supply of breathing air (not oxygen) for ground egress emergencies, which must be manually activated to be available. Four PEAP's were recovered, and there is evidence that three had been activated. The nonactivated PEAP was identified as the Commander's, one of the others as the Pilot's, and the remaining ones could not be associated with any crew member. The evidence indicates that the PEAP's were not activated due to water impact.

It is possible, but not certain, that the crew lost consciousness due to an in-flight loss of crew module pressure. Data to support this is:

The accident happened at 48,000 feet, and the crew cabin was at that altitude or higher for almost a minute. At that altitude, without an oxygen supply, loss of cabin pressure would have caused rapid loss of consciousness and it would not have been regained before water impact[/b].

PEAP activation could have been an instinctive response to unexpected loss of cabin pressure.

If a leak developed in the crew compartment as a result of structural damage during or after breakup (even if the PEAP's had been activated), the breathing air available would not have prevented rapid loss of consciousness.

The crew seats and restraint harnesses showed patterns of failure which demonstrates that all the seats were in place and occupied at water impact with all harnesses locked. This would likely be the case had rapid loss of consciousness occurred, but it does not constitute proof.

Much of our effort was expended attempting to determine whether a loss of cabin pressure occurred. We examined the wreckage carefully, including the crew module attach points to the fuselage, the crew seats, the pressure shell, the flight deck and middeck floors, and feedthroughs for electrical and plumbing connections. The windows were examined and fragments of glass analyzed chemically and microscopically. Some items of equipment stowed in lockers showed damage that might have occurred due to decompression; we experimentally decompressed similar items without conclusive results.

Impact damage to the windows was so extreme that the presence or absence of in-flight breakage could not be determined. The estimated breakup forces would not in themselves have broken the windows. A broken window due to flying debris remains a possibility; there was a piece of debris imbedded in the frame between two of the forward windows. We could not positively identify the origin of the debris or establish whether the event occurred in flight or at water impact. The same statement is true of the other crew compartment structure. Impact damage was so severe that no positive evidence for or against in-flight pressure loss could be found.

Finally, the skilled and dedicated efforts of the team from the Armed Forces Institute of Pathology, and their expert

consultants, could not determine whether in-flight lack of oxygen occurred, nor could they determine the cause of death.

/signed/

Joseph P. Kerwin

EDIT: a link about the history of the pressure suit http://en.wikipedia.org/wiki/Advanced_Crew_Escape_Suit

[GrndPndr]

From first launch to this day, Shuttle crews wear full pressure suits until established in orbit. Cabin depress isn't a factor.

I recall that coming out of the investigation as well.

Not quite true. After STS-51 everyone went back to full-pressure suits (First few flights featured full suits (Crippen and Young)). There were a number of schemes suggested after that, including a crew capsule (B1B, F111 style). Pressure suits were deemed the most effective (translation = cost-effective). <SNIP

Edited to add: "usaf36031" posted while I was typing.

Edited March 24, 2008 by GrndPndr

[usaf36031]

usaf36031 - right you are about the pressure suits. Apparently Challenger's crew was wearing standard NASA blue flightsuits (NOT pressurized), with a sealed helmet that delivered oxygen in case of cabin depress.

Still, it's hard to believe that they wouldn't put them in pressure suits given the altitudes that they're launching into. Just one of those things where hindsight is 20/20 I guess. I hope they were unconscious.

[JarheadBoom]

The following is from part of the MSNBC series I linked to. I feel it's worth it's own post, after that bullshit that TMZ posted about the continued search for MIA's...

The cabin wreckage was so twisted and tangled, sharp edges jutting everywhere like knife points, that the divers demanded the wreckage itself be hauled to the surface and the operation continued on deck.

The crew, the NASA teams and the astronauts overseeing the operation stood silently on the USS Preserver recovery ship as a crane lifted the wreckage from the sea. Every step possible to render respect and honor to the human remains was taken.

The salvage operations proceeded normally until the steel cables on the ocean bottom tugged at another section of Challenger’s middeck. At first the weight and mass seemed too great for the hoisting system. Slowly, painfully, the cables pulled the unseen wreckage from the bottom. Then the cables drew the load to the surface. Divers in the water, and everyone on deck, froze where they were.

A blue astronaut jumpsuit bobbed to the surface, turned slowly and then disappeared again within the sea.

What seemed liked minutes passed, in reality only seconds of time. Divers and sailors stood stunned as they realized what had happened. They had found — and just as quickly lost — astronaut Gregory Jarvis. Immediately the divers went deep again, beginning a frantic search for the last astronaut of Challenger, a frustrating search that would not end for another five weeks.

Reuniting the heroes

In the days following, armed forces pathologists made positive identifications of six astronauts from Challenger. The underwater search continued for the body of Gregory Jarvis.

The frustrations of failure day after day began to tell on everyone involved. No one wanted to declare “missing” someone so close to his own group, when they knew the body had every chance of being nearby.

Veteran shuttle pilots Robert Crippen and Bob Overmyer had been put in charge of the recovery of their fellow astronauts, and they would brook no interference from anyone, no matter how high they might be in the NASA hierarchy. Or from any other source. Crippen and Overmyer had decided that when the remains were turned over to the families, there would be seven coffins beneath the American flags. There would not be six. So desperate was Crippen to bring Jarvis home with the rest of his crew that he used his own credit card to hire a local scallop boat to drag its nets across the ocean bottom. Crippen’s move was a last-ditch effort in a search all but abandoned by the exhausted recovery forces.

On April 15, when the recovery teams were planning to cease the search they had carried out for months, divers were making what was scheduled to be their last attempts to gather wreckage from the ocean floor. Two hundred yards from where they had lost the blue suit, they swam within view of the lost astronaut.

The seventh crew member of Challenger was brought carefully to the surface. Ashore, finally, the Challenger Seven were reunited.

[Guest Jackonicko]

Moving stuff

[Toasty]

Sounds like there were unconscious. All bets off when unpressurized above the Armstrong line.

[usaf36031]

assuming the cabin was in fact depressurized of course.

[mhc257]

Talk to your safety shop guys to get the report from safety school. IIRC, a few of the astronauts actually drowned.

I doubt that after a 60,000 foot freefall the impact on the water was soft enough to survive, so drowning seems pretty unlikely. I'm a civilian not really in the know here, but I thought the official conclusion was that the 20ish g's they pulled when the rockets lost control caused inflight breakup (not explosion) at around 48,000, though the crew capsule continued on its trajectory up to about 60,000 feet. The "official statement" (don't have it handy...anyone else want to track it down?) said that it's pretty likely that the capsule depressurized causing loss of consciousness pretty quickly, and the capsule was crushed by the 200g+ impact with the water. My aerospace prof was on the investigation board - I'll ask him Tuesday.

Tragic day regardless. Here's one for the crew

[amcflyboy]

On another note...when they were raising the wreckage of the Challenger, they also found the wreckage of the infamous Flight 19. This was the flight of the four F4U Corsairs that were suspected of dissapearing over the Bermuda Triangle in 1945. Pretty freaky stuff!

[Guest thefranchise]

Without a pressure suit, knowing that 3 of 4 PEAPs manually activated, its safe to assume the astronauts survived the explosion, became unconscious but survived until the orbiter smashed into the water.

On the pressure suit topic, just as shocking, the Columbia reports show that 4 of the astronauts werent wearing the proper pressure suit equipment when it crashed on re-entry (although it wouldnt have helped in the mishap)

[ClearedHot]

On another note...when they were raising the wreckage of the Challenger, they also found the wreckage of the infamous Flight 19. This was the flight of the four F4U Corsairs that were suspected of dissapearing over the Bermuda Triangle in 1945. Pretty freaky stuff!

At no point in your rambling, incoherent response was there anything that could even be considered a rational thought. Everyone in this room is now dumber for having listened to it. I award you no points, and may God have mercy on your soul!

#1. Flight 19 was a flight of FIVE, not four TBM Avengers, not F4U Corsairs.

#2. A SINGLE TBM Avenger, not four....errr, five, was found during the Challenger recovery. The wreckage was raised in 1990, but positive identification could not be made.

The only thing freaky is your nonsensical post.

[M2]

Wikipedia on Flight 19...to include the one aircraft CH referred to...

In 1986, the wreckage of an Avenger was found off the Florida coast during the search for the wreckage of the Space Shuttle Challenger. Aviation archaeologist Jon Myer raised this wreck from the ocean floor in 1990. He was convinced it was one of the missing planes, but positive identification could not be made. In 1991, the wreckage of five Avengers was discovered off the coast of Florida, but engine serial numbers revealed they were not Flight 19. They had crashed on five different days "all within a mile and a half [~2.4 km] of each other." Records showed training accidents between 1942 and 1946 accounted for the loss of 94 aviation personnel from NAS Fort Lauderdale (including Flight 19). In 1992, another expedition located scattered debris on the ocean floor, but nothing could be identified. In the last decade, searchers have been expanding their area to include farther east, into the Atlantic Ocean. It has been determined through Navy records that the various discovered aircraft, including the group of five, were declared either unfit for maintenance/repair or obsolete, and simply disposed of at sea.

Cheers! M2

[uhhello]

At no point in your rambling, incoherent response was there anything that could even be considered a rational thought. Everyone in this room is now dumber for having listened to it. I award you no points, and may God have mercy on your soul!

#1. Flight 19 was a flight of FIVE, not four TBM Avengers, not F4U Corsairs.

#2. A SINGLE TBM Avenger, not four....errr, five, was found during the Challenger recovery. The wreckage was raised in 1990, but positive identification could not be made.

The only thing freaky is your nonsensical post.

Survey SAYS..............................FACE!!!!!!

[Scooter14]

Records showed training accidents between 1942 and 1946 accounted for the loss of 94 aviation personnel from NAS Fort Lauderdale (including Flight 19).

Holy fuck. I'm glad I'm not an Avenger pilot. WHo the fuck built, flew and maintained those lawndarts?

[JarheadBoom]

Holy ######. I'm glad I'm not an Avenger pilot. WHo the ###### built, flew and maintained those lawndarts?

The Grumman Ironworks and General Motors built them. The Navy flew and maintained them.

Look up the records for other training bases, both USN and USAAC, during the WWII days. Mishap rates were likely similar.

Related point (kinda): In the '50s, during the early days of jet-powered carrier aviation, the Navy lost the equivalent of ONE AIRPLANE PER DAY for a couple years before they came up with the NATOPS program. Look up those mishap rates for grins...

[Scooter14]

My question was meant to be more morbidly tongue-in-cheek than serious. Internet sarcasm transfer deficit disorder strikes again.

I bet I'd still want to be a pilot if I was born in 1923 as opposed to 1973, but I'm sure glad we know now what we didn't know then. The mishap rate back in the day was staggering. Even into the '50s and '60s it's amazing how many planes we lost. Hell, we were losing a few tankers a year back then, and that had four engines.

Here's to our brother aviators who went before us.

[JarheadBoom]

My question was meant to be more morbidly tongue-in-cheek than serious. Internet sarcasm transfer deficit disorder strikes again.

Gotcha. No biggie...

I bet I'd still want to be a pilot if I was born in 1923 as opposed to 1973, but I'm sure glad we know now what we didn't know then. The mishap rate back in the day was staggering. Even into the '50s and '60s it's amazing how many planes we lost. Hell, we were losing a few tankers a year back then, and that had four engines.

Here's to our brother aviators who went before us.

Absolutely... even though I'm not a pilot.

[M2]

Even bombers were bad...

The small wings and big engines made the B-26 a high performance plane that had high take off and landing speeds. It was an unforgiving aircraft for novice pilots. Bob Stevens drew a cartoon showing a B-26 pilot praying out loud as he took off from a too-short runway while carrying tons of ammunition. The unforgiving aspect of the plane gave it some other nicknames: "The Widow-Maker," and "A plane a day in Tampa Bay," which was near where they were training at McDill Field. Another Stevens cartoon shows a plane going into the bay while the pilot says "Now I know why they call it the flying torpedo."

Cheers! M2