The Scaled Composites Model 318 White Knight is a jet-powered carrier aircraft used to launch the SpaceShipOne experimental spacecraft. It was developed by Scaled Composites as part of their Tier One program.
White Knight first flew on 1 August 2002. The flight was aborted shortly after takeoff due to a problem with the outboard spoilers. White Knight next flew on August 5, 2002, and this time performed well. Development proceeded over the next few months. With White Knight developed and evaluated, on April 18, 2003 White Knight and SpaceShipOne were presented to the media.
Subsequently, White Knight flew as part of the Tier One program that won the Ansari X Prize on 2004 October 4. Afterwards White Knight was used to carry and launch DARPA's experimental X-37 spaceplane for its approach and landing tests in 2005 and 2006.