Challenger disaster: "obviously a major malfunction" and "the vehicle has exploded" - explained

I'd like to post a few thoughts on the Space Shuttle Challenger disaster, since after probing the detailed timeline of the disaster and a few articles and blog posts I found, it seems that a few points about the disaster and the perception of it in the public eye can be made more clear.

First, the probably infamous uttering "obviously a major malfunction" by the Public Affairs Officer and Mission Control spokesman Steve Nesbitt in Houston, right after the footage shows the expanding plume and disintegrating fragments of the Challenger. On the surface, this statement might be puzzling and sound like a big understatement. But it helps to get things into perspective: usatoday30.usatoday.com...

Nesbitt's job, as the official public voice of NASA going out to the world during the launch, was to provide a running stream of information. The data came from what today seems like an amazingly primitive source — a single black and white, 9-inch monitor with lines of numbers and cryptic letters scrolling across constantly.

On a piece of paper in front of him Nesbitt also has the mission timeline, a listing of what was supposed to happen second-by-second with the shuttle. "About every 15 seconds there was a new milestone coming in on the timeline," he says.

[...]

He and the rest of Mission Control were in a windowless, concrete room that was 1,000 miles west of Cape Canaveral where Challenger was launched.

Nesbitt was focused on the 9-inch computer screen in front of him, reading off numbers. The only actual visual of the launch he could see was a small television off to his left but he couldn't watch it and the computer so he wasn't looking at it.

The launch was proceeding smoothly when Mission Control said "Challenger, go with throttle up," and Challenger answers back, "Roger, go with throttle up."

Breaking back in in a calm voice, Nesbitt read off his screen: "One minute 15 seconds. Velocity 2,900 feet per second. Altitude nine nautical miles. Downrange distance seven nautical miles."

What he couldn't see, but the image that burned into the brains of millions of Americas, was that just as the astronauts on Challenger throttled up, the craft burst into a bright ball of flame. The camera pulls back to show two separate streams of smoke veering first apart and then together, then twisting around in a wild dance.

Sitting next to him was the Navy flight surgeon for the launch, a young captain. "I heard her say 'What was that?' " Nesbitt remembers.

He finished reading the numbers off the screen and then looked over at the TV screen. "At that point there was just the trail of smoke. And I thought 'Oh, crap. There's something not right.' "

There's a 15-second pause between his last words, "seven nautical miles," and the next ones. Neither Nesbitt nor anyone in the room knew what had happened. "I'm not hearing anyone in Mission Control saying 'The spacecraft just disintegrated.' No one's saying anything," he says.

Something was horribly wrong, he knew that. But he had no idea what it was, what had happened to the spacecraft and, most importantly, what had happened to the crew.

What Nesbitt did know was that it was his job to explain to the public what they were seeing on their TV screens. "I had this feeling 'I've got to comment on what's happening,' but I didn't have any information."

So the next words he uttered were the now famous quote: "Flight control is here looking very carefully at the situation, obviously a major malfunction."

Some at the time expressed surprise that his voice never changed during the next hour as the full extent of the tragedy became evident. But that wasn't Nesbitt's job: It was to give accurate information as quickly and smoothly as he could.

As you can see, there was very little information for Nesbitt to go on. A "major malfunction" was really all he could say with certainty.

~~~

Second point, is whether the Challenger actually exploded. Nesbitt's words "We have a report from the flight dynamics officer that the vehicle has exploded.", as well as the general appearance of the disaster, will certainly lead many people to believe so, which has been reflected in many articles, videos, and other accounts of the disaster.

But the Challenger didn't explode. It rapidly disintegrated due to the compromised structure and the aerodynamic forces. Some burning did occur, but it involved mostly the hydrazine fuel in the Shuttle's maneuvering control system. The liquid Hydrogen and Oxygen in the main tank simply escaped and expanded as vapour.

So why did Nesbitt say "the vehicle has exploded"? This was a slightly innacurate wording of what really happened, if you examine the detailed timeline of the disaster at spaceflightnow.com...

Relevant parts:

T+110.250
Range safety control officers send radio signals that detonate the self-destruct package on right-hand solid rocket.

T+110.252
The left-hand booster self destructs.

T+2 min 25 sec
FIDO: "Flight, FIDO."
Greene: "Go ahead."
FIDO: "RSO (range safety officer) reports vehicle exploded."

T+2 min 50 sec
Nesbitt: "We have a report from the flight dynamics officer that the vehicle has exploded. The flight director confirms that.

Basically, what happened was the controlled destruction of the SRBs by the Range Safety Officer, who is responsible for the safety of people and buildings on the ground from possible damage from the falling rocket debris and fuel. In a standard emergency scenario (such as engine failure, or loss of control), detonating the SRBs would have lead to the inevitable loss of the whole Shuttle stack, hence the wording "RSO reports vehicle exploded", referring not just to the SRBs but to the whole Shuttle stack. But the "vehicle" WAS exploded, it hadn't exploded by itself.

In fact, while the SRBs were exploded, the rest of the Shuttle simply disintegrated.

This situation was a 'fog of war' kind of thing. Surprise ... grabbing for words ... getting as close to accurate as could happen in the quick event. It was a shock. They weren't ready for it. I thought the announcer fella did okay.

I had heard that officials would later find out that the crew were found with water in their lungs. which meant they were still alive when the shuttle came to rest in the ocean.

a reply to: Glassbender777

I've heard something similar. I've heard that they were conscious all the way down until they hit the water, and there was some recordings of chatter inside the shuttle.

Not sure if there is any truth to that though.

originally posted by: Glassbender777
I had heard that officials would later find out that the crew were found with water in their lungs. which meant they were still alive when the shuttle came to rest in the ocean.

The impact of the crew compartment against water would have killed them instantly.

Was there even enough of the bodies left for an autopsy after all the time in water? www.lutins.org...

They had been in 95 feet of warmish ocean water, in an area teeming with life, for six weeks. They were not really recognizable as former people. Such soft tissue as remained had become almost gelatinous and very delicate. Some had taken on a waxy, soapy texture, due to a hydrolysis reaction that takes place in seawater over time. Recovery was not a simple task. There was damage from shrimp and crabs.

Tat link above is another whole story about the Challenger disaster, a real conspiracy this time.

a reply to: MystikMushroom

SNOPES claims that the tape of the crew didn't happen. However, I think it's one of those things that NASA would have covered up quickly. And the crew compartment was well intact so I"m thinking they didn't die way up in the air. They may have passed out from lack of oxygen or something. But I really don't see them dying when the shuttle blew around them.

I could be wrong. We will never know.

a reply to: FlyersFan

I just read through that...

It seems that some of the crew activated their air packs, so they did know that something odd was going on.

Here's a good video analysis of the last milliseconds of the Challenger, detailing its breakup: www.youtube.com...

As the ET broke up, the released fluids vaporized rapidly, producing an expanding cloud of gasses, vapors, and cryogenic fluid with embedded debris and localized combustion of mixed gasses. No shockwave or other evidence of a violent explosion was detected in the imagery. The illumination from the combination of the SRB plume radiance, reflected sunlight, and the periferal burning of gasses, gives the cloud the appearance of a fireball.

a reply to: wildespace

That concludes the design was faulty, but the decision to launch in such a low temperature was as much to blame. It was striking to me that one of the astronauts told his wife that the launch would likely be scratched due to the low temperature, so his wife was surprised the launch proceeded.

The sad thing is there was no reason to have a joint like the one that failed in the SRBs, because some of the contractors bidding on the job could deliver a large one piece SRB to the launch site using a barge. The joint design was a concession to a landlocked bidder Morton Thiokol, who couldn't deliver anything by barge. From that perspective it was an entirely preventable design flaw. I always wondered what the real backstory was on how Morton Thiokol got considered to make the SRB in several pieces rather than one piece, if there was some political pressure to do so, or what.

This brings back some memories that I'd rather have forgotten. We had flown two helicopters down from Jacksonville to watch the launch from the Transient Line at Patrick AFB. We tried to launch right after the explosion, but, couldn't get clearance due to the possibility of falling debris. We were looking in case someone had managed to get out but, all we found were debris. We picked up what we could and took it back to Patrick. I remember being in a club that night and punching out a guy for making a lame ass joke about NASA standing for "Need Another Seven Astronauts". About two days later a large section washed up on the beach behind my house.

a reply to: JIMC5499

Wow, so you were there? Are you a rescue swimmer?

a reply to: parad0x122

Long long time ago in a .............