Re: Famous Saturn V footage

"Pat Flannery" wrote:

Originally, the Saturn V had eight downward facing solid fuel
ullage/separation motors on S-1C/S-II interstage, and eight upward facing
solid fuel braking engines mounted in pairs in the four semi-conical
fairings at the base of the S-1C stage to facilitate separation of the two
After a few flights it was seen that less energy was needed to
successfully separate the two units; so it was modified by having four of
the interstage engines removed in the J-series Apollo missions. I don't
know if they reduced the number of braking motors at the S-1C stage's base
or not.

Apollo's 4 and 6 (both unmanned) had 8 ullage rockets on the S-1C/S-II

Apollo's 8 - 14 (8 - 10 = "G" series, 11 - 14 = "H" series) had 4 ullage
rockets on the S-1C/S-II interstage.

Apollo's 15 - 17 ("J" series) and the Skylab Saturn V did not have any
ullage rockets on the S-1C/S-II interstage.

Interestingly, the S-1C/S-II interstage failed to separate during staging on
the Skylab launch, something not well known no doubt due to the other far
more significant and infamous problem of Skylab's meteoroid shield being
stripped off the lab taking a solar panel away as well prior to S-1C/S-II