Ascent propulsion system

Ascent propulsion system (APS)
Apollo LM ascent engine
Country of originUnited States
Date1964–72
ManufacturerBell Aircraft / Rocketdyne
ApplicationLunar Ascent Stage/Spacecraft propulsion
PredecessorBell 8247
SuccessorRS-18
StatusRetired
Liquid-fuel engine
PropellantN
2
O
4
/ Aerozine 50
Mixture ratio1.6
CyclePressure-fed
PumpsNone
Configuration
Chamber1
Nozzle ratio46
Performance
Thrust, vacuum3,500 pounds-force (16 kN)
Thrust-to-weight ratio16.7 (weight on Earth)
Chamber pressure120 psia
Specific impulse, vacuum311 seconds (3.05 km/s)
Burn time465 seconds
RestartsDesigned for 2 restarts
Dimensions
Length51 inches (130 cm)
Diameter31 inches (79 cm)
Dry mass210 pounds (95 kg)
Used in
Lunar module as ascent engine
References
References[1]

The ascent propulsion system (APS) or lunar module ascent engine (LMAE) is a fixed-thrust hypergolic rocket engine developed by Bell Aerosystems for use in the Apollo Lunar Module ascent stage. It used Aerozine 50 fuel, and N
2
O
4
oxidizer. Rocketdyne provided the injector system, at the request of NASA, when Bell could not solve combustion instability problems.[2]

  1. ^ Bartlett, W.; Kirkland, Z. D.; Polifka, R. W.; Smithson, J. C.; Spencer, G. L. (February 7, 1966). Apollo spacecraft liquid primary propulsion systems (PDF) (Technical report). Houston, TX: NASA, Manned Spacecraft Center. pp. 8–9. 70N35721. Archived (PDF) from the original on August 23, 2022. Retrieved August 23, 2022.
  2. ^ Cite error: The named reference LMAE was invoked but never defined (see the help page).