From: "Tony Ingenoso" 

Yes, expected service life was around 100 launches/orbiter.

Back in 80'-83' when I was with Rockwell, (internal) engineering
predictions were for a total loss of vehicle and crew in about 1:100
flights.  That expected failure rate wasn't for public or political
consumption though of course.

Very sad day...

I had a personal attachment to Columbia.  She was my first job out of
college and I baby sat her DEU's on a 24hr watch during STS-1. I didn't
know any of this crew, but I'd met a couple of the final Challenger crew. 
This sucks.

"Randy H"  wrote in message
news:3e3bf501{at}w3.nls.net...
> 120,000 ft up, travelling at Mach 6.
>
> The taking heads were saying that the shuttle frames were 'certified'
> for 100 launches, Columbia was the oldest and heaviest in
> the fleet.

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