Did you know the F-104 was tested being launched like a rocket, with no runway?

Zero-Length Launch, or ZeLL, was a German modification devised to solve how to launch high-performance fighters without a long runway. The aircraft was placed on a short ramp with a booster rocket attached underneath. The rocket fired and launched the jet into the air within seconds; once airborne and at sufficient speed, the booster was jettisoned and the aircraft continued flying on its own engine.

Conventional aircraft, dependent on large, well-known air bases, were considered too easy to destroy in the first hours of a major conflict between the superpowers. In the event of a sudden war, conventional runways could become targets and be rendered useless.

A Lockheed F-104G appears in the trials carried out at Edwards Air Force Base. The tests with the F-104 and other jets proved the concept worked, but Zero-Length Launch never entered regular service. The complexity, cost, and risk outweighed the benefits, and air forces chose instead to harden airfields and disperse aircraft to protect them. All ZELL aircraft projects were abandoned, largely for logistical reasons and also because the growing effectiveness of guided missiles made their adoption less critical.