The Space Review'', Monday, March 13, 2006 RobotPig.net - TSTO spaceplanes presentation of a Boeing TSTO patent, the Blackstar TSTO and the respective technologies The Register: Blackstar: the US space conspiracy that never was?, Lester Haines, April 24, 2006 Spaceplanes Crewed spacecraft 1990s United States experimental aircraft Rocket-powered aircraft