The
XLR99 was used to power the X-15 research aircraft and was
the first large liquid propellant rocket capable of being throttled
and restarted. The engine used up to 10,000 lbs of fuel per
minute.
The XLR99 was also known as the Pioneer.
Liquid-fuel rocket
Fuel: anhydrous ammonia
Oxidizer: liquid oxygen (LOX)
Models
Used
by
XLR99-RM-2: 57,000 lb (250 kN) thrust
(at high altitude)