Huntsville in Madison County, Alabama — The American South (East South Central)
Main Engines
Power for Lift-off and Ascent to Orbit
Photographed By Sandra Hughes, September 20, 2016
1. Main Engines Marker
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.
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
Topics. This historical marker is listed in these topic lists: Air & Space • War, Cold. A significant historical year for this entry is 1981.
Location. 34° 42.647′ N, 86° 39.156′ W. Marker is in Huntsville, Alabama, in Madison County. Marker can be reached from Tranquility Base, 0.4 miles west of Madison
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Other nearby markers. At least 8 other markers are within walking distance of this marker. External Tank (a few steps from this marker); T-38 Talon (within shouting distance of this marker); Pathfinder (within shouting distance of this marker); Pathfinder Orbiter (within shouting distance of this marker); U.S. Army/NASA Juno II (about 500 feet away, measured in a direct line); NASA / U.S. Geological Survey (about 500 feet away); U.S. Army PGM-11 Redstone (about 500 feet away); Ms. Baker: Monkeynaut (about 600 feet away). Touch for a list and map of all markers in Huntsville.
Also see . . . U.S. Space & Rocket Center. (Submitted on September 22, 2016.)
Photographed By Sandra Hughes, September 20, 2016
2. Main Engines Marker
Credits. This page was last revised on August 16, 2020. It was originally submitted on September 21, 2016, by Sandra Hughes Tidwell of Killen, Alabama, USA. This page has been viewed 481 times since then and 30 times this year. Photos: 1, 2. submitted on September 21, 2016, by Sandra Hughes Tidwell of Killen, Alabama, USA. • Bernard Fisher was the editor who published this page.
