# Do rockets leave launch pad at full thrust? Tags: launch - Score: 32 - Views: 7954 - Answers: 3 - Answered: yes - Asked by: user36480 - Asked: 2021-01-10 - Site: space ## Question Rockets always seem to launch slower than I expect them for the thrust they can produce. Do they really launch off the pad at maximum thrust? Or do they launch at lower thrust until they clear the tower? I'm always surprised when I see how slow they seem to budge from the pad. I know they're massive, but still. ## Answers ### Answer by Organic Marble (score: 22 [ACCEPTED]) As in many things, shuttle was an exception, the answer for it is No. At liftoff the Space Shuttle Main Engines were running at a throttle setting of 100% of their rated power level. About 4 seconds after liftoff they throttled up to 104.5%. The maximum emergency throttle setting was 109%, but this was never used in flight. Screenshot from a Shuttle Mission Simulator run showing the commands from T-4 through the thrust bucket. (the commands at 1:22 are a response to a failure inserted into the sim run) ### Answer by Russell Borogove (score: 43) Rockets always seem to launch slower than I expect them for the thrust they can p