Historic Markers Across Alabama

Main Engines

Marker ID:  
Location: 1 Tranquilty Base, Huntsville, AL
County: Madison
Coordinates: N 34° 42.647    W 086° 39.156
  34.71078333    -86.6526
Style: Interpretative Sign **
Waymark: None


Main Engines
Power for Lift-off and Ascent to Orbit

The Pathfinder's three main engines are real. The two lower engines powered the first flight of Columbia in 1981. The engine located at the top was used in ground test firings.

At launch, the three Space Shuttle Main Engines (fed liquid hydrogen and oxygen from the External Tank) are ignited several seconds before liftoff.

They operate for approximately 8.5 minutes of flight, drawing about 47,000 gallons of liquid hydrogen and 17,000 gallons of liquid oxygen each minute. Shortly before the shuttle achieves orbit the Main Engines shut down and maneuvering rockets fire to position the Shuttle into its final orbit. Reusable each engine is designed for 7.5 hours of operation or to endure up to 55 starts.
Data Each engine
Length: 14 ft
Diameter: 7.5 ft
Weight: approximately 7000 lbs.
Thrust: 393,800 lbs.
Mix ratio: 6 parts oxygen to 1part hydrogen
Prime Contractor: Rockwell International Rocketdyne Division

End of Main Engines