Pat Flannery wrote:
Ed Kyle wrote:

I've posted a rarely seen photo of the last Saturn IB booster stage,
built for
the SA-214 vehicle, at the following address.

"http://geocities.com/launchreport/sa214.html"

Today, with the agency scrambling to develop a new Saturn IB class
Crew Launch Vehicle, it almost hurts to view this photograph of one of
three powerful booster stages that NASA saw fit, in another time, to
scrap.



Yeah, but it was pretty large and heavy for its capabilities, and eight
motors is about where you start to worry about the odds of a
catastrophic single engine failure occurring and destroying the stage.

The S-IB stage wasn't as heavy as it looked. It actually compares
well with the Zenit 3 first stage - which can be considered a modern
equivalent in that it uses the same propellants and delivers about the
same total impulse. S-IB had a propellent mass ratio of about 0.907.
The Zenit first stage propellent ratio is about 0.909.

And although it is not a fair comparison (because different propellents

are used), it is still interesting to note that SRB and Delta 4 CBC are

both "heavier", relatively speaking, than S-IB. SRB has a 0.846
propellant mass ratio, Delta 4 CBC has a 0.882 ratio.

As for the probability of catastrophic engine failure, it would be
interesting to compare the probability of a CATO in an H-1 cluster
with the probability of a CATO in an SRB.

- Ed Kyle