Ryan XV-5 Vertifan

The Ryan XV-5 Vertifan was a jet-powered V/STOL experimental aircraft in the 1960s. The U.S. Army commissioned the Ryan VZ-11RY (which was redesignated as the XV-5 in 1962) in 1961, along with the Lockheed VZ-10 Hummingbird (redesignated as the XV-4).

Design
The XV-5 drove three fans. Engine gases from two 3,000 lbf (13 kN) thrust J85 turbojets, similar to those used in the F-5 Freedom Fighter were sent to exit by turning fans. It was much simpler in concept, if not execution, compared to the future F-35 Lightning II which has one fan driven by a driveshaft, balanced by a rotating rear nozzle. There was a large fan in each wing with covers resembling half garbage can lids that flipped up for vertical flight. The 36 inch (0.9 m) nose fan provided adequate pitch control but made flying tricky. The fans provided vertical thrust of approximately 16,000 lbf, nearly three times the horizontal thrust of the engines alone.

A set of louvered vanes underneath each of the large wing fans could vector the thrust in any direction and provided yaw control. Each jet engine could be controlled for RPM. Wing fan RPM was determined by the output from the J85 engines and fan flow at the fan inlets. Roll control was by differential actuation of the wing-fan exit louvers.

The project performance was moderately subsonic, with delta wings somewhat like an A-4 Skyhawk. The Vertifan also featured a fan in the nose, an unusual intake situated above the two-seat side-by-side seating cockpit, and a T-tail.

The XV-5A was finished in Army green, while the XV-5B was painted in white NASA colors. The fans did generate as much thrust as was hoped, and the vertical-horizontal flight transition was difficult and abrupt. The XV-5 would be one of the last manned aircraft designed and built by Ryan, which mainly manufactured drones after the mid 1960s.

The XV-5 was one of many dozens of aircraft which attempted to produce a successful vertical takeoff aircraft, but the lift fan system was heavy and occupied considerable internal volume. Only the Hawker Siddeley Harrier would still be operational by the turn of the 21st century, as would technology to make possible the use of a shaft-driven fan in the F-35.

Operational history
Two 12,500 lb (maximum gross weight) XV-5A were evaluated in late 1966 by fifteen test pilots (the "XV-5A Fan Club"). One was destroyed in a crash during a public flight demonstration on 27 April 1965, killing Ryan test pilot Lou Everett. Tests and promotional materials proposed a rescue version that could winch a person into a compartment behind the pilots. The second aircraft was extensively damaged in 1966 during trials as a rescue aircraft, when the test dummy was ingested into a wing fan. The pilot, Bob Tittle, was fatally injured, although it was judged that the fan actually still functioned well enough to continue controlled flight. The second aircraft was rebuilt as the modified XV-5B, with tests continuing until 1971. An XV-5B can be seen on display at the Fort Rucker Aviation Museum, Alabama.