stormiestl ◾ 7 Myths about the Challenger Shuttle disaster (Reply)

I remember exactly where I was and where my children were on this day. We lived in Houston, Texas. My oldest son and his entire school were watching this on television. My youngest, my mother and I were watching this from home. It was with great anticipation because of one teacher. Then things went badly. It became clear that the teachers and administraters had to deal with this immediately. They asked all parents that called to please leave the kids in school. They had counselors talking to the children as a whole and individually. I chose to let my son stay in school. Post traumatic stress syndrome resulted with a lot of the children that watched the Challenger lift off that day. Mine included. Many still refuse to watch the lift off of ANY shuttle or rocket of any kind. Regardless of what the reasoning behind the explosion was, it affected a nation. One way or the other. It affected how we look at things related to space flight. Has NASA learned from this? No. Another Shuttle exploded on re-entry for some of the same reasons. Did NASA learn from that? Only time will tell. I am wholeheartedly for space exploration. I just wish the government would stay out of it. Let those that understand the shuttle and other things under development do their jobs. A politician has no place in NASA.

7 myths about the Challenger shuttle disaster
It didn't explode, the crew didn't die instantly and it wasn't inevitable

By James Oberg

NBC News space analyst

Special to MSNBC

Updated: 11:25 a.m. ET Jan. 27, 2006

HOUSTON
- Twenty years ago, millions of television viewers were horrified to
witness the live broadcast of the space shuttle Challenger exploding 73
seconds into flight, ending the lives of the seven astronauts on board.
And they were equally horrified to learn in the aftermath of the
disaster that the faulty design had been chosen by NASA to satisfy
powerful politicians who had demanded the mission be launched, even
under unsafe conditions. Meanwhile, a major factor in the disaster was
that NASA had been ordered to use a weaker sealant for environmental
reasons. Finally, NASA consoled itself and the nation with the
realization that all frontiers are dangerous and to a certain extent,
such a disaster should be accepted as inevitable.

At
least, that seems to be how many people remember it, in whole or in
part. That’s how the story of the Challenger is often retold, in oral
tradition and broadcast news, in public speeches and in private
conversations and all around the Internet. But spaceflight historians
believe that each element of the opening paragraph is factually untrue
or at best extremely dubious. They are myths, undeserving of popular
belief and unworthy of being repeated at every anniversary of the
disaster.

The
flight, and the lost crewmembers, deserve proper recognition and
authentic commemoration. Historians, reporters, and every citizen need
to take the time this week to remember what really happened, and
especially to make sure their memories are as close as humanly possible
to what really did happen.

If that happens, here's the way the mission may be remembered:

Few people actually saw the Challenger tragedy unfold live on television.

The shuttle did not explode in the common definition of that word.

The flight, and the astronauts’ lives, did not end at that point, 73 seconds after launch.

The
design of the booster, while possessing flaws subject to improvement,
was neither especially dangerous if operated properly, nor the result
of political interference.

Replacement of the original asbestos-bearing putty in the booster seals was unrelated to the failure.

There were pressures on the flight schedule, but none of any recognizable political origin.

Claims
that the disaster was the unavoidable price to be paid for pioneering a
new frontier were self-serving rationalizations on the part of those
responsible for incompetent engineering management — the disaster
should have been avoidable.

Myth #1: A nation watched as tragedy unfolded
Few
people actually saw what happened live on television. The flight
occurred during the early years of cable news, and although CNN was
indeed carrying the launch when the shuttle was destroyed, all major
broadcast stations had cut away — only to quickly return with taped
relays. With Christa McAuliffe set to be the first teacher in space,
NASA had arranged a satellite broadcast of the full mission into
television sets in many schools, but the general public did not have
access to this unless they were one of the then-few people with
satellite dishes. What most people recall as a "live broadcast" was
actually the taped replay broadcast soon after the event.

Myth #2: Challenger exploded
The
shuttle did not explode in the common definition of that word. There
was no shock wave, no detonation, no "bang" — viewers on the ground
just heard the roar of the engines stop as the shuttle’s fuel tank tore
apart, spilling liquid oxygen and hydrogen which formed a huge fireball
at an altitude of 46,000 ft. (Some television documentaries later added
the sound of an explosion to these images.) But both solid-fuel
strap-on boosters climbed up out of the cloud, still firing and
unharmed by any explosion. Challenger itself was torn apart as it was
flung free of the other rocket components and turned broadside into the
Mach 2 airstream. Individual propellant tanks were seen exploding — but
by then, the spacecraft was already in pieces.

Myth #3: The crew died instantly
The
flight, and the astronauts’ lives, did not end at that point, 73
seconds after launch. After Challenger was torn apart, the pieces
continued upward from their own momentum, reaching a peak altitude of
65,000 ft before arching back down into the water. The cabin hit the
surface 2 minutes and 45 seconds after breakup, and all investigations
indicate the crew was still alive until then.

What's
less clear is whether they were conscious. If the cabin depressurized
(as seems likely), the crew would have had difficulty breathing. In the
words of the final report by fellow astronauts, the crew “possibly but
not certainly lost consciousness”, even though a few of the emergency
air bottles (designed for escape from a smoking vehicle on the ground)
had been activated.

The
cabin hit the water at a speed greater than 200 mph, resulting in a
force of about 200 G’s — crushing the structure and destroying
everything inside. If the crew did lose consciousness (and the cabin
may have been sufficiently intact to hold enough air long enough to
prevent this), it’s unknown if they would have regained it as the air
thickened during the last seconds of the fall. Official NASA
commemorations of “Challenger’s 73-second flight” subtly deflect
attention from what was happened in the almost three minutes of flight
(and life) remaining AFTER the breakup.

Myth #4: Dangerous booster flaws result of meddling
The
side-mounted booster rockets, which help propel the shuttle at launch
then drop off during ascent, did possess flaws subject to improvement.
But these flaws were neither especially dangerous if operated properly,
nor the result of political interference.

Each
of the pair of solid-fuel boosters was made from four separate segments
that bolted end-to-end-to-end together, and flame escaping from one of
the interfaces was what destroyed the shuttle. Although the obvious
solution of making the boosters of one long segment (instead of four
short ones) was later suggested, long solid fuel boosters have problems
with safe propellant loading, with transport, and with stacking for
launch — and multi-segment solids had had a good track record with the
Titan-3 military satellite program. The winning contractor was located
in Utah, the home state of a powerful Republican senator, but the
company also had the strengths the NASA selection board was looking
for. The segment interface was tricky and engineers kept tweaking the
design to respond to flight anomalies, but when operated within tested
environmental conditions, the equipment had been performing adequately.

Myth #5: Environmental ban led to weaker sealant
A
favorite of the Internet, this myth states that a major factor in the
disaster was that NASA had been ordered by regulatory agencies to
abandon a working pressure sealant because it contained too much
asbestos, and use a weaker replacement. But the replacement of the seal
was unrelated to the disaster — and occurred prior to any environmental
ban.

Even
the original putty had persistent sealing problems, and after it was
replaced by another putty that also contained asbestos, the higher
level of breaches was connected not to the putty itself, but to a new
test procedure being used. “We discovered that it was this leak check
which was a likely cause of the dangerous bubbles in the putty that I
had heard about," wrote physicist Richard Feynman, a member of the Challenger investigation board.

And
the bubble effect was unconnected with the actual seal violation that
would ultimately doom Challenger and its crew. The cause was an
inadequate low-temperature performance of the O-ring seal itself, which
had not been replaced.

Myth #6: Political pressure forced the launch
There
were pressures on the flight schedule, but none of any recognizable
political origin. Launch officials clearly felt pressure to get the
mission off after repeated delays, and they were embarrassed by
repeated mockery on the television news of previous scrubs, but the
driving factor in their minds seems to have been two shuttle-launched
planetary probes. The first ever probes of this kind, they had an
unmovable launch window just four months in the future. The persistent
rumor that the White House had ordered the flight to proceed in order
to spice up President Reagan’s scheduled State of the Union address
seems based on political motivations, not any direct testimony or other
first-hand evidence. Feynman personally checked out the rumor and never
found any substantiation. If Challenger's flight had gone according to
plan, the crew would have been asleep at the time of Reagan's speech,
and no communications links had been set up.

Myth #7: An unavoidable price for progress
Claims
that the disaster was the unavoidable price to be paid for pioneering a
new frontier were self-serving rationalizations on the part of those
responsible for incompetent engineering management — the disaster
should have been avoidable. NASA managers made a bad call for the
launch decision, and engineers who had qualms about the O-rings were
bullied or bamboozled into acquiescence. The skeptics’ argument that
launching with record cold temperatures is valid, but it probably was
not argued as persuasively as it might have been, in hindsight. If
launched on a warmer day, with gentler high-altitude winds, there’s
every reason to suppose the flight would have been successful and the
troublesome seal design (which already had the attention of designers)
would have been modified at a pace that turned out to have been far too
leisurely. The disaster need never have happened if managers and
workers had clung to known principles of safely operating on the edge
of extreme hazards — nothing was learned by the disaster that hadn’t already been learned, and then forgotten.