HOTOL

Horizontal Take-Off and Landing

Mission Profile

HOTOL (Horizontal Take-Off and Landing) was a revolutionary British single-stage-to-orbit spaceplane concept developed by British Aerospace engineer Alan Bond from 1982, designed to take off from a conventional runway using a novel hybrid air-breathing and rocket engine called the RB545. Projected to be 63 m long with a liftoff mass of 250 tonnes and a LEO capacity of 7,000 kg, HOTOL aimed to dramatically reduce launch costs by enabling aircraft-like operations and reusability. Though ultimately deemed impractical in its original classified form due to technical and funding challenges, HOTOL pioneered many spaceplane concepts that directly influenced subsequent British programs, including the Skylon vehicle.