Linear Aerospike SR-71 Experiment

LASRE was NASA's Linear Aerospike SR-71 Experiment which took place at the Dryden Flight Research Center at Edwards Air Force Base, California, until November 1998. The experiment sought to provide flight data to help Lockheed Martin validate and tune the computational predictive tools used to determine the aerodynamic performance of the Lockheed Martin X-33 lifting body and linear aerospike engine combination and to lay groundwork for a future reusable launch vehicle.

Source: Wikipedia — Linear Aerospike SR-71 Experiment (CC BY-SA 4.0)