[Jim Noble]

>> I thought I heard that each orbiter had a life expectancy of 100 flights<<

You and I have heard a lot of things.

The actual catastrophic failure rate is 1/50. With four orbiters, that means 200 trips and it's over.

And the losses are of course losses of irreplaceable heroes and explorers, not merely billions of dollars of steel and silicon.

The mission concepts and the lack of alternatives or followon vehicles are simply not consistent with a failure rate of 1:50.

[George W. Bush]

>> I thought I heard that each orbiter had a life expectancy of 100 flights<< You and I have heard a lot of things. The actual catastrophic failure rate is 1/50. With four orbiters, that means 200 trips and it's over.

Well, do the math.

They expected the airframes to last 100 missions. But since the original estimate was that we'd lose a shuttle once every 75 missions, there was a 33% chance that any of them would last the 100 missions to begin with.

Space is dangerous. But we need to keep going. And we need a new fleet, with boosters for heavy lift and smaller space planes or capsules for manned flight. The shuttle is too complex and tries to do too many things and costs too much to fly. We need better vehicles.