(John Pelchat) wrote in message . com...


Was the 2 booster noozles/1 sustainer
nozzle as considered to be one MA-5A engine? Did the Atlas sustainer
and boosters share a lot of equipment that made them suitable to
consider it all one engine?

According to Boeing:

"The Rocketdyne MA-5A propulsion *system* consists of a
429,500 lb thrust booster *engine* with two thrust *chambers* and
a 60,500 lb thrust sustainer *engine* all using liquid oxygen and
RP-1 as propellants. ... Both bell-shaped booster thrusters are
connected to a central power package consisting of a turbopump
for each chamber, a single gas generator, a pneumatic control
package, and a liquid oxygen regulator. The sustainer engine
turbopump is engine-mounted."

So Boeing considered it a system consisting of two engines -
a two chambered booster and a single-chambered sustainer.

... it must have taken a lot of
engineering to design it such that when the booster skirt was
jettisoned, that the shared equipment came a part in such a way that
the sustainer had what ever it needed to continue to operate.

You betcha. Atlas development was part of one of the largest
military-industrial efforts ever marshalled by the United
States. Atlas was a troubled bird for quite a few years.
Go see a real Atlas at Cape Canaveral (not Kennedy Space Center)
or the one in Huntsville to get an idea of how complicated the
engine section was.

Was the first stage of Titan
II considered to have two engines, or an single engine with two
nozzles?

According to the U.S. Air Force:

"Titan II was boosted by an Aerojet LR87-AJ-5 two chamber
liquid propellant rocket engine of 430,000 lbs. thrust"

- Ed Kyle