| Liquid Hydrogen
The liquid hydrogen tank is
an aluminum semimonocoque structure of fusion-welded barrel sections,
five major ring frames, and forward and aft ellipsoidal domes. Its
operating pressure range is 32 to 34 psia. The tank contains an
anti-vortex baffle and siphon outlet to transmit the liquid hydrogen
from the tank through a 17-inch line to the left aft umbilical.
The liquid hydrogen feed line flow rate is 465 pounds per second
with the SSMEs at 104 percent or a maximum flow of 47,365 gallons
per minute. At the forward end of the liquid hydrogen tank is the
ET / orbiter forward attachment pod strut, and at its aft end are
the two ET / orbiter aft attachment ball fittings as well as the
aft SRB-ET stabilizing strut attachments. The liquid hydrogen tank
is 331 inches in diameter, 1,160 inches long, and has a volume of
53,518 cubic feet and a dry weight of 29,000 pounds.