) Maiden flight April 12 , 1981 Notable payloads International Space Station components Hubble Space Telescope Galileo Magellan Chandra X-ray Observatory Boosters (Stage 0) - Solid Rocket Boosters No boosters 2 Engines 1 solid Thrust 12,455 kN (approx. 3,300,000 lbf each, sea level liftoff) Specific impulse 269 s Burn time 124 s Fuel