STS-123 landing
I’m Mr. Know-it-all when it comes to the space program and all, but does anyone know what those flames are?
I have two theories: a) Left over heat from re-entry or b) left over fuel being burned off…
UPDATE: The jets of flame are the exhaust of the APUs (auxiliary power units) which power the hydraulics that move the Shuttles control surfaces. After landing, they need the hydraulics to put the main engines in a “rain drain” position so rainwater doesn’t pool in the engines. They also move the body flap on the bottom of the Shuttle. The flames are the exhaust of the APUs.
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Could they be the exhaust from the APUs - Auxillary Power Units?
I believe you are correct… I thought the APU’s were just turbine engines, but it turns out that the flames are completely normal. You just don’t see it during daytime landings.