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Old February 3rd 17, 11:49 AM posted to sci.space.history
Stuf4
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Default The Space Race was about Power Projection - Miles O'Brien

From Fred McCall:
Jeff Findley wrote:

In article ,
says...

On Saturday, January 28, 2017 at 5:39:54 PM UTC-6, Stuf4 wrote:

snip
As it was, the only shuttles that were disintegrated happened
as a result of lack of care, rather than anything intentional.

Correct, they were management failures, not technological failures.


To be fair, middle level shuttle managers were put in a bad spot by the
higher ups. They had to manage what amounted to an experimental program
and pretend it was an "operational" program after five test flights.
The higher ups put a huge amount of pressure on middle management to
increase the flight rate. This created the management culture of "if
we're going to ground it, you have to prove to me it will fail", which
doomed the Challenger crew.

Middle managers were also forced to do this with a budget which was
smaller than it should have been. An example of this was right before
Challenger there was a distinct lack of spare parts. They were pulling
parts from recently returned orbiters so they could be installed on
another orbiter which was being prepared to fly. Imagine if you had two
cars and had to pull the cylinder head from one and install it on the
other when you wanted to use it. Insane, right?

To begin with, the SRBs ought to have been replaced with reusable liquid
boosters, but that would have been *quite* expensive to develop (which
is why SLS is still using solids). Other improvements, like non-toxic
OMS/RCS propellants and replacing the APUs and hydraulics with
electrically operated actuators would have improved the turn-around time
and reduced the risks to ground crews.

Unfortunately, SLS/Orion seems to have given up on reuse which creates a
vicious cycle of low flight rates and high launch costs. The very low
flight rate is bad for safety for a variety of reasons. Imagine a job
where every task you perform has to be done perfectly, but you only do
each task every other year, so you are assigned hundreds of tasks to
perform for each mission. You'd have little chance to get better at
your tasks, since by the time you have to repeat a task, you will have
forgotten most of what you learned from doing it the last time.


There are times when I think Usenet needs a 'Like' button...


I myself see a lot to be in wanting in Jeff's post.


JF: Imagine if you had two cars and had to pull the cylinder head from one and install it on the other when you wanted to use it. Insane, right?"

That is called "cannibalization", and a very common practice in high performance aerospace vehicles. Hardly ideal, but a cost-effective approach to maintenance.


JF: "the SRBs ought to have been replaced with reusable liquid boosters"

A fact that so many people are willing to ignore is that the SRBs performed totally adequately for 24 straight missions. They never failed a single time. So that's 48 SRB successes in a row. 144 field joints did their job.

The only time they failed was when NASA decided to launch with temps WAY OUT OF LIMITS. Here is an exact quote from Thiokol's Bob Ebeling:

"[W]e're only qualified to 40 degrees ...'what business does anyone even have thinking about 18 degrees, we're in no man's land.'"
(https://www.nasaspaceflight.com/2007...of-challenger/)

THAT is the one and only proximate cause of the Challenger disaster.

....and the culpability for this fatal error falls not only on NASA top management, nor middle management, but the one level of decision-making that everyone, for whatever reason, chooses to avoid mentioning:

- Operations.

THEY were the ones whose duty was to know these limits better than anyone else involved in the launch decision. Yet all of them decided to not voice their objections. That goes for the dozens upon dozens of people in Launch Control, the many dozens in Mission Control, and also the crew themselves.

The crew paid for this mistake with their lives.
Other people in operations like Gene Thomas, Bob Sieck, Jay Greene, Fred Gregory, etc got *promoted*.

That's the most effective way to cover up an egregious error. Everybody pretend that it never happened. That it wasn't their job to stop the launch. It's much easier to blame an inanimate object like O-rings even though they had a track record of a 100% success rate when launched within temp limits.

SRB field joints had a batting average of 1000. 144 successes with 144 at bats.

Not a perfect design, to be sure. But it worked when established limits were respected.

O-rings are *NOT* what killed Scobee and his crew. It was every person involved in the chain that arrived at the decision that it was a good idea to launch in spite of the freezing cold temps.


And it likewise needs to be identified that also culpable for these 7 fatalities is everyone from back in the 1970s who was involved in the decision to not give shuttle crews a viable means of escape. It would have been very easy to have designed the crew cabin as a breakaway structure. Being a pressure vessel, it was already robust. Not much more was needed than a stabilization drogue chute and thermal protection. A set of very light tiles or blankets would have done the trick. From there, all the crews would have needed was pressure suits with parachutes.

Such a simple low cost lightweight low-performance-impact solution would have saved 14 lives. Or if it failed in saving lives, it would have at least given them a fighting chance. Some glimmer of hope for survival.

In the case of 51-L, something as simple as a sport parachute might have made the difference between living and dying. This is *half* of what recreational parachutists use on a daily basis. Just give the astronauts the "reserve". But no. They were not even given that much.

~ CT