Thread: CEV PDQ
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  #20  
Old May 9th 05, 09:00 PM
Pat Flannery
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Rand Simberg wrote:

So we don't care if we lose a billion-dollar payload? Or the price of
relaunching?

This notion of reliability being of no relevance for unmanned systems
gets tiresome.



Not to the same degree... for a manned launch you want around 99+%
reliability if at all possible; for unmanned you can settle for 95%-97%
(like most operational expendable rockets have) and realize that the
loss of a couple in 100 launches will be more than offset by the money
you save in not having to design and build to quite the high standards
required to get to 99+%. It's where those last few percentage points
start coming into play that you run into lots of added dollars- and
extra equipment weight to overbuild things to make critical things
redundant. Which cuts into your payload weight, and therefore ups your
launch price per pound for large numbers of launches.

Pat