Detail of the number 5
engine liquid hydrogen feed line (at center of the photo). Also note the
number 2 engine feed line at the top of the photo.
The S-shaped duct at lower left is the
engine compartment conditioning duct.
The engine compartment conditioning system provided 300 to 500 pounds per
minute of gaseous nitrogen to the engine compartment to prevent hazardous gas
accumulation, formation of liquified air (due to the extreme temperatures of
the liquid hydrogen), and to maintain proper thrust structure temperature.