Fueling of the Shuttle required a lot of propellant as the
External Tank held over 500,000 gallons of propellants. Two
spheres on opposite sides of the pad perimeter, approxi-
mately 3,000 feet apart, held the propellants until they were
pumped into the Shuttle’s External Tank. One tank could
hold up to 900,000 gallons of liquid oxygen at –297 degrees
Fahrenheit while the other tank could hold 850,000 gallons of
liquid hydrogen at –423 degrees Fahrenheit. The propellants
were transferred from the storage tanks in vacuum-jacketed
lines that feed into the orbiter and External Tank via the tail
service masts on the mobile launcher platform.
The Apollo blast room was mothballed and instead a new
Emergency Egress System was installed. The new system was
located at the 195 level of the FSS, the same height as the
Crew Access Arm, and is a slide wire system with baskets for
astronauts and pad workers to speedily escape the pad in
the event of an emergency. In 135 launches, the system was
never used, however if it had been, fire nozzles would release
heavy sprays of water over the pad area. Remember earlier
I mentioned how the 195 foot level had a solid floor? The
water spray would be so heavy that the crew and pad per-
sonnel would only be able to see their feet and the floor, so
a bright yellow pathway was painted on the floor, sometimes
humorously referred to by the pad and crew as the Yellow
Brick road, this would lead them to the escape baskets.
At the slidewire basket landing
area, STS-116 crew members sit
in one of the baskets used for
emergency egress away from the
launch pad. From left are Pilot
William Oefelein and Mission
Specialists Joan Higginbotham
and Christer Fuglesang.
Credit: NASA/Kim Shiflett
Seven baskets and slide wires were in place, each basket
capable of transporting three people to the ground some
1200 feet to the west of the pad in just 90 seconds. The
basket would reach a top speed of 55 MPH and would be
slowed by a drag chain before coming to a complete stop
in the catch net at the end of the system. When reaching
the ground, the crew and pad personnel would find a bun-
ker and one or more M-113 Armored Vehicles. In the event of
an imminent detonation, the bunker could provide the best
protection; otherwise they would board the M-113 Armored
Vehicles and make a hasty departure to a safe zone more
than a mile away from the pad.
Another addition to the pad would be the Sound Suppres-
sion Water System. With the orbiter so close to the Mobile
Launcher, the sound waves produced by the three Space
Shuttle Main Engines and the massive Solid Rocket Boosters
upon ignition could have possibly damaged anything in the
orbiter’s cargo bay and possibly the orbiter itself. The solution
was to reduce the sound waves with a flow of water over the
Mobile Launch Platform and the pad itself. A 300,000 gallon
water tank located on the northeast side of the pad contains
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