This Quick Time movie shows the Space Shuttle Solid Rocket Booster (SRB) separation from the external tank (ET). After separation, the boosters fall to the ocean from which they are retrieved and refurbished for reuse. The Shuttle?s SRB?s and solid rocket motors (SRM?s) are the largest ever built and the first designed for refurbishment and reuse. Standing nearly 150-feet high, the twin boosters provide the majority of thrust for the first two minutes of flight, about 5.8 million pounds. That is equivalent to 44 million horsepower, or the combined power of 400,000 subcompact cars.