The aerospike engine is a type of rocket engine that maintains its aerodynamic efficiency across a wide range of altitudes. It belongs to the class of altitude compensating nozzle engines. Aerospike engines were proposed for many single-stage-to-orbit (SSTO) designs. They were a contender for the Space Shuttle main engine. However, as of 2023 no such engine was in commercial production, although some large-scale aerospikes were in testing phases.
Test Firing of Linear Aerospike Engine - GPN-2000-000066
Linear Aerospike SR-71 Experiment (LASRE) ground cold flow test. NASA Photo
Non-truncated toroidal aerospike nozzle
Dryden Aerospike Rocket Test (4858567714)
Launch of the first Dryden Aerospike rocket. The Dryden Aerospike Rocket Test provided the first known data from a solid-fueled aerospike rocket in flight.
Chuck Rogers, Trong Bui, and Scott Bartel make preflight checks on the second of two aerospike research rockets on March 31, 2004.
Trong Bui, NASA Dryden's principal investigator for the aerospike rocket tests, holds the first of two 10-ft. long rockets that were flown at speeds up to Mach 1.5, the first known supersonic tests of rockets with aerospike nozzles.