Sigh.
As I have posted many times before, a careful analysis of all space
launches worldwide between 1980 and 2010 shows that liquid stages (of space
launch vehicles) fail twice as often as solid stages.
Even if we ignore all non-western launches, liquid stages still fail more
often, although not quite twice as much.
The reason for this difference appears to be complexity. An open
question—for which there is some statistical evidence—is whether reuse
improves reliability, a potential advantage that would tend to favor liquid
stages.
Bill
On Tue, Apr 28, 2020 at 4:03 PM roxanna Mason <rocketmaster.ken@xxxxxxxxx>
wrote:
On the liquid side of the equation let's throw in the liquid Centaur,
almost 100% except for that pesky purge failure where the turbopump iced up
preventing its start up. So a know failure mode led to a reliable fix a
hindsight issue of fixing something that worked just fine.
On Tue, Apr 28, 2020 at 2:51 PM Henry Spencer <hspencer@xxxxxxxxxxxxx>
wrote:
On Tue, 28 Apr 2020, George Herbert wrote:
I would add the Titan III and IV solids to those numbers. Segmentation
is a good breakpoint.
Also the original H-II solids. JAXA switched to one-piece solids for the
H-IIA and H-IIB. Ironically, although the switch was partly meant to
improve reliability, I think the only big-solid failure they've had came
*after* the switch -- hot-gas leak caused a separation failure.
Henry
