In the early 1960s, Ryan Aeronautical did something that sounded like a fever dream: they cut two large holes in the wings of a jet aircraft, installed massive fans inside them, and tried to make the whole thing hover like a helicopter. The truly astonishing part is that it worked. The XV-5 Vertifan could take off vertically, transition to conventional forward flight, and land vertically again �� all powered by redirecting exhaust from a pair of General Electric J85 turbojet engines into tip-driven fans embedded in the wing structure. Two were built. One crashed. The other survived and sits in a museum, a monument to an era when American aviation engineers believed that any problem could be solved by pointing a jet engine at it.

How Do You Put a Fan in a Wing?

The XV-5’s concept was elegant in theory and brutal in execution. Two General Electric J85 turbojet engines sat in conventional nacelles on the fuselage. For normal forward flight, their exhaust went straight out the back, and the XV-5 flew like any other small jet — reasonably fast, reasonably agile, nothing special.

The magic happened when the pilot activated the VTOL system. Diverter valves redirected the engine exhaust away from the tailpipes and into a network of ducts that fed two large fans embedded in the wings and a smaller fan in the nose. The wing fans were 1.6 metres in diameter — enormous openings cut directly through the wing structure — and were driven by the jet exhaust hitting turbine blades at the tips of the fan. The nose fan provided pitch control during hover. The fans pulled air down through the wing, generating vertical lift. Doors on the top and bottom of the wing opened to allow airflow through the fan duct. In hover, the XV-5 looked like a conventional jet aircraft floating improbably on columns of downwash — which is exactly what it was. The transition between hover and forward flight was the most dangerous phase. The pilot had to simultaneously close the fan doors, redirect exhaust back to the tailpipes, and accelerate through the speed range where the fans provided lift but the wings did not yet generate enough aerodynamic lift to sustain flight. The margin for error was measured in seconds and feet.

One Crash, One Survivor

The XV-5A first flew conventionally in May 1964 and achieved its first hover in November of the same year. The flight test program was cautious and methodical — VTOL aircraft had killed many test pilots, and Ryan’s engineers knew the transition phase was where the danger lived.

On April 27, 1965, during a hover demonstration at Edwards Air Force Base, the first XV-5A (serial 62-4505) suffered a control failure and crashed, killing test pilot Major Richard C. Johnson. The investigation concluded that the aircraft had entered an uncontrollable descent during low-altitude hover — the kind of accident that plagued nearly every VTOL experimental program of the era. The second XV-5A was later rebuilt as the XV-5B with improved control systems and transferred to NASA for continued research. It flew extensively through the late 1960s, accumulating valuable data on fan-in-wing VTOL concepts, before being retired and preserved.

Legacy of the Fan-in-Wing

The XV-5 never entered production. The US Army ultimately decided that helicopters were a more practical solution for battlefield VTOL — cheaper, simpler, and far more mature. The fan-in-wing concept required cutting enormous holes in the primary lifting structure, which weakened the wing and added weight and complexity that negated much of the performance advantage. But the idea did not die. Lockheed Martin’s F-35B Lightning II — the short-takeoff/vertical-landing variant used by the US Marines and Royal Navy — uses a lift fan that is a direct conceptual descendant of the XV-5’s approach. The F-35B’s LiftSystem, designed by Rolls-Royce, is a shaft-driven fan mounted behind the cockpit that generates 20,000 pounds of vertical thrust. The engineering is entirely different — shaft-driven rather than tip-driven — but the core principle is identical: use a fan embedded in the airframe to generate vertical lift without the complexity of a full helicopter rotor. The Ryan XV-5 proved that fan-in-wing VTOL was physically possible. It took 50 years and several trillion dollars of defence spending for the idea to finally reach a production combat aircraft. Sometimes in aviation, being right too early looks exactly like being wrong. Sources: NASA technical reports, Ryan Aeronautical archives, US Army Aviation Museum