The Pratt & Whitney J75 is a turbojet engine designed for military aircraft, first introduced in the 1950s. It was known for its high thrust output and reliability, making it suitable for various fighter jets and bombers. The J75 was a significant advancement in jet engine technology during its time. This engine features a two-spool design, which allows for improved efficiency and performance at different speeds. It powered several aircraft, including the McDonnell Douglas F-4 Phantom II and the Lockheed F-104 Starfighter, contributing to the capabilities of the U.S. Air Force and other military forces around the world.