Space Shuttle Columbia (inset top)
arrives at Launch Pad 39A on Dec. 29,
1980, in preparation for its maiden
liftoff on April 12, 1981.
the water used in the system. Using gravity alone, the water
is dumped onto the MLP and the Flame Trench of the pad
via a system of quench nozzles, also known as “rainbirds”.
When a Shuttle would launch, the intense heat from the en-
gines would turn much of the water into steam, resulting in
the large white cloud seen around the pad prior to booster
ignition.
Attached to the FSS is the Rotating Service Structure or
RSS. The main purpose of the RSS is to allow installation and
servicing of the Shuttle’s payload for that mission, at the pad.
It also allows technicians access to certain systems on the
orbiter. A typical Shuttle launch begins a month or so prior to
liftoff when the Shuttle, aboard the Mobile Launch Platform,
is moved to the pad. Having payload installation at the pad
allows the payload to be loaded much further along in the
launch processing.
Measuring in at a healthy 102 feet long, by 50 feet wide,
and 130 feet high, the RSS is quite a sight on its own. It ro-
tates 120 degrees and is moved away from the Shuttle well
before fueling and launch. The Payload Changeout Room
is the main feature of the RSS. It’s an environmentally con-
trolled area that is enclosed and supports the delivery of
the payload to the orbiter’s payload bay. Also if the pay-
load requires any servicing at the pad it is performed there.
Inside there are five platform levels that allow access to the
payload.
Two other parts of the RSS, the Orbiter Midbody Umbilical
Unit, and the Hypergolic Umbilical unit, provide access and
service to two important areas of the orbiter. The first provides
fluids to the orbiter’s reactant storage and distribution system
as well as fuel for the orbiter’s three fuel cells. The Hypergolic
Umbilical Unit supplies Hypergolic fuel and oxygen service
lines along with helium and nitrogen service lines which sup-
ply the orbiter’s Orbital Maneuvering System (OMS) pods.
Of the 135 Space Shuttle missions, Pad 39A served as the
launch pad for 80 of them, including the first mission, STS-1,
and the last mission, STS-135.
Other notable Space Shuttle
missions to launch from Pad 39A
Space Shuttle Atlantis (inset left) is
seen as it lifts off from Kennedy Space
Center to begin the STS-132 mission
on May 14, 2010. Credit: Chase Clark
The exhaust plume (left) from Space
Shuttle Atlantis is seen through the
window of a Shuttle Training Aircraft
(STA) as it launches from NASA’s
Florida spaceport on July 8, 2011.
Credit: NASA/Dick Clark
• STS-7, which carried Sally Ride, the first female American
Astronaut into orbit
• STS-41c, the first mission to retrieve, repair, and re-deploy
a satellite (SolarMax)
• STS-82 – the second Hubble Space Telescope servicing
mission
• STS-103 – the third Hubble Space Telescope servicing
mission
• STS-109 – the fourth Hubble Space Telescope servicing
mission (The last successful mission by Columbia)
• STS-125 – the fifth and final Hubble Space Telescope ser-
vicing mission
• Also many of the International Space Station assembly
missions, Spacehab missions, and Shuttle/Mir docking
missions were launched from Pad 39A. Pad 39A saw the
last launch of every orbiter except for Challenger.
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