Mike Coslo wrote:
wrote:
K4YZ wrote:
an_old_friend wrote:
wrote:
What does this have to do with ham radio? Plenty!
For one thing,
ham radio is mentioned in the second article.
mentioned
Yep.
Did anyone besides me actually read the articles I linked?
The Space Shuttle was promoted as the "next big thing"
in space travel
- as a "space truck" that would cut the cost of
getting to orbit,
reducing the waste of one-time rockets, etc. We were
told of turnaround
times of a few weeks, and missions costing 10 to
20 million dollars
total - none of which has ever come to pass, 30
years after the program began.
yea the shutle was and is a failure
Based upon WHAT data, Mark?
It's a fact that the Space Shuttle program has not reached *some*
of the goals set for it. OTOH it has reached and exceeded some
of the goals, too.
The Space Shuttle program is neither a complete success nor a total
failure. It's done many great things, but not everything
that was expected.
But that's not the point I was making.
That people have been killed flying it? So what?
No Americans died flying the Mercury, Gemini or Apollo missions. The
Apollo 1 fire that killed astronauts Grissom, Chaffee and White
happened during a ground training/checkout session.
People die on
commecial airliners on a monthly basis. Are airliners a
failure?
There's a big difference.
The chances of dying in a commercial airliner accident are extremely
small. The failure rate of commercial airline flights (where "failure"
equals "people died") is extremely small. In fact if you drive to the
airport, fly around the world on First World commercial airliners
(returning to your point of origin), and drive home, the most dangerous
part of the trip is the drive to and from the airport, statistically
speaking.
One of the statistics that is trotted out when
speaking of airline
safety is passenger miles. I suspect the shuttle
would fare *very* well
if we applied passenger miles to it! ;^)
Not really.
Let's do the math...
The following are rough numbers. Those willing to do more looking-up
are invited to give more exact numbers, and see how close my
approximations are.
IIRC, there have been 113 Shuttle missions that "went the distance" so
far. Missions last about a week and have about seven astronauts on each
one.
Orbital velocity is about 18,000 miles per hour and a week is 168 hours
long.
So a typical mission is about 3 million miles long. With seven
astronauts aboard, that's 21 million passenger miles per mission.
113 x 21 = about 2.4 billion passenger miles in the entire shuttle
history.
But two missions ended with total loss of the crew - 14 deaths. That's
one death for every 171 million passenger miles. Compare that to the
commercial airliner rate...
Or take a look at another measu Number of deaths per million
aircraft departures. Commercial airlines are well under one per
million. The Shuttle is around 1 in 8.
Of course both measures are a bit off the mark. Most commercial airline
accidents have some survivors.
Perhaps the most accurate measure would be "what are the chances that a
flight will be completed without an accident that results in the death
of a passenger? In the case of the Shuttle, the demonstrated odds are 1
in 57. Commercial airliners are a lot better....
73 de Jim, N2EY