Bell X-22

infobox Aircraft
name = X-22
type = V/STOL prototype
manufacturer = Bell Aircraft Corporation

---

caption = Bell X-22 on the tarmac
designer=
first flight=17 March 1966
primary user= Bell
more users=
introduction=
retired=
number built= 2
status= 1 preserved in museum
unit cost=
variants with their own articles= The Bell X-22 was a United States V/STOL X-plane with four tilting ducted fans. Take-off was to selectively occur either with the propellers tilted vertically upwards, or on a short runway with the nacelles tilted forward at approximately 45°. Additionally, the X-22 was to provide more insight into the tactical application of vertical take-off troop transporters such as the preceding Hiller X-18 and the X-22 successor, the Bell XV-15. Another program requirement was a true airspeed in level flight of at least 525 km/h (283 knots; 326 mph).

Three-blade propellers were mounted on four wings and, synchronized through a wave-interconnection system, were connected to four gas turbines which themselves were mounted in pairs on the rear wings. Maneuvering was achieved by tilting the propeller blades in combination with control surfaces (elevators & ailerons), which were located in the thrust stream of the propellers.

History

In 1962, the US Navy announced their request for two prototype aircraft with V/STOL capability, powered by four ducted fan nacelles. Bell Helicopter already had intensive experience with VTOL aircraft and was able to utilize an already developed test mockup. In 1964 the prototype, internally referred to by Bell as Model D2127, was ordered by the Navy and received the X-22 designation.

Maiden flight of the prototype occurred on March 17th, 1966. In contrast to other tilt-rotor craft (such as the Bell XV-3), transitions between hovering and horizontal flight succeeded nearly immediately. However, interest increased more towards VTOL and V/STOL properties, not the specific design of the prototype.

Due to failure of a prop control, described by the test pilot, Stanley Kakol, as the only non redundant component in the power chain, the prototype crashed on August 8th, 1966 and technicians stripped it for components in order to make the second prototype flight capable. The fuselage was still used as a simulator for some time afterwards.

The second X-22 first flew on August 26th 1967. Early that year, it was equipped with a variable flight control and stabilizer system from Cornell Aeronautical Laboratory, which improved flight performance. Although the X-22 was considered to be the best aircraft of its type at the time, the program was canceled. The required minimum speed of 525 km/h was never reached. The second prototype was moved to Cornell Aeronautical Laboratory for further testing; the last flight occurred in 1988. The craft is currently on display in the Niagara Aerospace Museum, New York.

Although the ducted fan propellers were considered usable, they were never utilized again on a US military aircraft.

pecifications (X-22A)

aircraft specifications
plane or copter?=plane
jet or prop?=prop
ref=
crew=Two
capacity=
payload main=
payload alt=
length main= 39 ft 7 in
length alt= 12.07 m
span main= 39 ft 3 in (rear wings) / 22 ft 11 in (front wings)
span alt= 11.96 m / 7.01 m
height main= 20 ft 8 in
height alt= 6.31 m
area main=
area alt=
airfoil=
empty weight main= 10,478 lb
empty weight alt= 4,763 kg
loaded weight main=
loaded weight alt=
useful load main=
useful load alt=
max takeoff weight main= 17,644 lb
max takeoff weight alt= 8,020 kg
more general=
* Propeller Diameter: 2.13 m (7 ft)
engine (prop)= General Electric-YT58-GE-8D
type of prop=turboshafts
number of props=4
power main= 1,267 hp
power alt= 932 kW
power original=
max speed main=221 knots
max speed alt= 410 km/h / 255 mph
cruise speed main=
cruise speed alt=
stall speed main=
stall speed alt=
never exceed speed main=
never exceed speed alt=
range main= 445 mi
range alt=712 km
ceiling main= 27,800 ft
ceiling alt= 8,475 m
climb rate main=
climb rate alt=
loading main=
loading alt=
thrust/weight=
power/mass main=
power/mass alt=
more performance=
* Hovering Altitude with Wing In Ground: 12,000 ft (3,658 m)
* Hovering Altitude without Wing In Ground: 6,000 ft (1,829 m)
armament=
avionics=

ee also

aircontent
related=

similar aircraft=
V-22
sequence=
X-19 -
X-20 -
X-21 - X-22 -
X-23 -
X-24 -
X-25
lists=

see also=

External links

* [http://avia.russian.ee/vertigo/bell_x-22-r.html avia.russian.ee]
* [http://aerospaceweb.org/aircraft/research/x22/ aerospaceweb.org]