Galaxy5 From United States of America, joined Mar 2000, 2034 posts, RR: 23
Reply 3, posted (12 years 4 months 3 weeks 21 hours ago) and read 8379 times:
Each engine has three primary levels of thrust or power - minimum, rated and full power. Engine thrust, however, can be varied throughout the range from minimum to full power level depending on mission needs. Shuttle payloads will be sized to be compatible with launch-to-orbit at a maximum of 104 percent of rated power level, with each engine developing 2,174,286 Newtons (488,000 pounds) of thrust, 1,734,803 Newtons (390,000 pounds) at sea level. full power level (109 percent of rated power) will be available for use in emergency situations. During the latter part of ascent, engine thrust will be reduced to insure that an acceleration force of no more than three times that of Earth's gravity is reached. This acceleration level, permitted by the throttleable Shuttle engines, is about one-third the acceleration experienced on previous manned space flights and is well under the physical stress limits of non-astronaut scientists who fly aboard the Shuttle. The lowest thrust throttle setting - minimum power level - equals 65 percent of rated power.
"damn, I didnt know prince could Ball like that" - Charlie Murphy
B2707SST From United States of America, joined Apr 2003, 1386 posts, RR: 58
Reply 6, posted (12 years 4 months 3 weeks 19 hours ago) and read 8342 times:
According to NASA, each solid rocket booster provides about 3.3 million pounds of thrust at takeoff. As Galaxy5 mentioned, the three hydrogen-burning main engines provide another 393,000 pounds of thrust each, or 1.179 million pounds for all three.
Total system thrust at takeoff is about 7.779 million pounds. The orbiter/SRB vehicle weight at takeoff is usually around 4.5 million pounds (the orbiter and payload typically account for about 270,000 pounds, the rest coming from the solid rocket boosters and the liquid hydrogen external tank).