The Bell X-22 is an American V/STOL X-plane equipped with four tilting ducted fans.
It was designed for take-off either by tilting the propellers vertically upwards or using a short runway with the nacelles angled forward at approximately 45°.
Furthermore, the X-22 aimed to enhance understanding of the tactical use of vertical take-off troop transporters, following the Hiller X-18 and preceding its successor, the Bell XV-15.
The initial test flight of the prototype took place on March 17, 1966, distinguishing itself from other tilt-rotor crafts like the Bell XV-3 by swiftly transitioning between hovering and horizontal flight.
However, the focus of interest shifted towards the VTOL and V/STOL capabilities rather than the specific design of the prototype.
Unfortunately, on August 8, 1966, the prototype crashed due to a propeller control failure, which test pilot Stanley Kakol described as the sole non-redundant component in the power chain.
In order to enable the second prototype to fly, technicians salvaged components from the crashed aircraft.
Although the fuselage continued to serve as a simulator for a period of time, it was stripped of its usable parts.
The second X-22 took its inaugural flight on August 26, 1967.
Earlier that year, it had been outfitted with a variable flight control and stabiliser system provided by Cornell Aeronautical Laboratory, resulting in improved flight performance.
Despite being regarded as the leading aircraft of its kind during that era, the program was ultimately terminated.
The desired maximum speed of 525 km/h was never achieved.
The second prototype was subsequently transferred to Cornell Aeronautical Laboratory for further examination, with its final flight occurring in 1988.
Specifications
Crew
Two
+
Six passengers
Length
39 ft 7 in (12.07 m)
Wingspan
39 ft 3 in (11.96 m)
Wingspan
(front wing)
22.916 ft (6.98 m)
Height
20 ft 8 in (6.31 m)
Empty weight
10,478 lb (4,753 kg)
Max take-off weight
17,644 lb (8,003 kg)
Powerplant
4 × General Electric-YT58-GE-8D turboshaft engines,
1,267 hp (945 kW) each
Propellers
Three bladed propellers mounted in wingtip swivelling ducts,
7 ft 0 in (2.13 m) diameter
Performance
Maximum speed
221 kn (254 mph, 409 km/h)
Range
387 nmi (445 mi, 716 km)
Service ceiling
27,800 ft (8,500 m)
Hover ceiling in ground effect
12,000 ft (3,658 m)
Hover ceiling out of ground effect
6,000 ft (1,829 m).
Sources U.S. Experimental & Prototype Aircraft Projects: Fighters 1939–1945-B Norton. The American Fighter from 1917 to the present – E Angelucci. Bell Aircraft Since 1935-A J Pelletier.
