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Editorial Information

Marshall Space Flight Center, AL 35812

Phone: 256-544-0030
Marshall website

The Marshall Star is published online every Wednesday by the Public and Employee Communications Office at the George C. Marshall Space Flight Center, National Aeronautics and Space Administration. Submissions should be written legibly and include the originator's name.

Send email submissions to:

Manager of Public and Employee
Dom Amatore

Editor: Amie Cotton

Fact Sheet

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Amazing Facts: Reusable Solid Rocket Booster
  • The world's largest solid rocket. At 149 feet high and 12 feet wide, it was one-half the length of a football field.

  • The twin boosters produced 6.6 million pounds of thrust at space shuttle liftoff.

  • Space shuttle solid rocket boosters went to full power in 2/10th of a second. The heat they produced in the first two minutes of flight could heat 87,000 houses for one full day.

  • After two minutes, the boosters separated at 28 miles altitude at a speed of 3,100 mph. They coasted upward for 13 miles before beginning their descent. After their burn out, they separated from the external tank by electrically fired explosive devices and were moved away by small rocket separation motors, four near the nose of each and four aft.

  • The solid rocket motor was the largest solid propellant motor ever developed for spaceflight and the first built to be used on a manned craft. The huge motor was composed of a segmented motor case loaded with solid propellants, an ignition system, a movable nozzle and the necessary instrumentation and integration hardware.

  • Each solid rocket motor contained more than 1 million pounds of propellant, which required an extensive mixing and casting operation at a plant in Utah. The propellant was mixed in 600 gallon bowls located in three different mixer buildings. The propellant was then taken to special casting buildings and poured into the casting segments.

  • Cured propellant looks and feels like a hard rubber eraser. The combined polymer and its curing agent is a synthetic rubber. The solid fuel was actually powdered aluminum -- a form similar to the foil wraps in your kitchen -- mixed with oxygen provided by a chemical called ammonium perchlorate.

  • In addition to the solid rocket motor, the booster contained the structural, thrust vector control, separation, recovery, and electrical and instrumentation subsystems.

  • Three 136-foot-wide parachutes slowed the boosters to a safe splashdown in the Atlantic Ocean.

  • The boosters were recovered, refurbished and reused.

  • The boosters were the heaviest objects ever to be parachuted safely back to the Earth's surface.