The Martin X-23 PRIME (Precision Recovery Including Maneuvering Entry) was a small uncrewed lifting body re-entry vehicle tested by the United States Air Force in the late 1960s. PRIME 3 mission was flown on 19 April 1967 and simulated reentry from low-earth orbit with a 1143 km cross-range. This time, all systems performed perfectly, and the X-23 was successfully recovered.