McDonnell XF-88 Voodoo

XF-88 Voodoo

Role: Escort fighter
Manufacturer: McDonnell
First flight: 20 October 1948
Status: Cancelled
Primary user: United States Air Force
Number built: 2
Program cost: US$6.6 million
Developed into: F-101 Voodoo

The McDonnell XF-88 Voodoo was a long-range, twin-engine jet fighter aircraft designed for the United States Air Force. Although it never entered service, its design was adapted for the subsequent F-101 Voodoo.

Design and development

The XF-88 originated from a 1946 United States Army Air Forces requirement for a long-range 'penetration fighter' to escort bombers to their targets. It was to be essentially a jet-powered replacement for the wartime P-51 Mustang that had escorted B-17 Flying Fortress bombers over Germany. It was to have a combat radius of 900 mi (1,450 km) and high performance. McDonnell began work on the aircraft, dubbed Model 36, on 1 April 1946. On 20 June the company was given a contract for two prototypes designated XP-88. Dave Lewis was Chief of Aerodynamics on this project.

Picture - The engineering team stands after Flight 100.

The initial design was intended to have a V-shaped tail, but wind tunnel tests indicated aerodynamic problems that led to an extensive redesign. The USAAF (which became the United States Air Force on 17 September 1947) approved the changes. When the USAF altered its designation scheme in 1948, the still unflown prototypes were redesignated XF-88. It was dubbed Voodoo.

The Voodoo had a low/mid-mounted wing, swept to 35°. The two engines were in the lower fuselage, with jetpipes beneath the rear fuselage. The prototypes carried XJ34 engines, although the production F-88A would have had two Westinghouse J46 turbojets with 5,920 lbf (26.33 kN) each. Intakes were mounted in the wing roots. The Voodoo's short nose had no radar, being intended to house an armament of six 20 mm (.79 in) M39 cannon.

Picture - Supersonic jet-turboprop hybrid XF-88B

The first XF-88 made its maiden flight on 20 October 1948. It had non-afterburning engines and no armament. It proved to be underpowered, leading to the decision to install afterburners on the second prototype, which was designated XF-88A and made its first flight on 26 April 1949. (The first prototype was modified to the same standard.)

In a subsequent paper competition against the Lockheed XF-90 and North American YF-93, the Voodoo lost to the XF-93, but the decision on production was later delayed until a 'fly-off' competition could be held. In that fly-off, held in the summer of 1950, the XF-88 proved the winner, but changes in Air Force requirements led the penetration fighter to be cancelled entirely.

Picture - Landing the XF-88

McDonnell proposed a naval version of the XF-88, a two-seat operational trainer, and a reconnaissance variant, but none were built. The first prototype was modified to XF-88B standard, with a nose-mounted Allison T38 turboprop engine added to the two existing turbojets. This was used for flight testing through 1956, and achieved speeds slightly exceeding Mach 1.0, the first propeller-equipped aircraft to do so. Both prototypes were scrapped by 1958.

A considerably enlarged version of the basic design was developed following the cancellation of the XF-88, becoming the F-101 Voodoo, the first production version of which flew on 29 September 1954. The basic layout of two engines under the tail would also appear in the redesign of an upgraded F3H Demon which would see service as the very successful F-4 Phantom II.

Operators

United States

United States Air Force

Variants

XF-88A XF-88B

Specifications (XF-88A)

General characteristics

Crew: one
Length: 54 ft 1.5 in (16.5 m)
Wingspan: 39 ft 8 in (12.1 m)
Height: 17 ft 3 in (5.3 m)
Wing area: 350 ft² (32.5 m²)
Empty weight: 12,140 lb (5,508 kg)
Loaded weight: 18,500 lb (8,394 kg)
Max takeoff weight: 23,100 lb (10,477 kg)
Powerplant: 2x— Westinghouse J34-WE-22 afterburning turbojets, 4,825 lbf (21.4 kN) each

Performance

Maximum speed: 706 mph (1,130 km/h)
Range: 1,737 mi (2,779 km)
Service ceiling: 39,400 ft (12,012 m)
Rate of climb: 8,000 ft/min (40 m/s)
Wing loading: 52.9 lb/ft² (258 kg/m²)
Thrust/weight: 0.44

Armament

6 x— 20 mm (.79 in) M39 cannon

Related development

F-101 Voodoo
CF-101 Voodoo

Comparable aircraft

Lockheed XF-90
North American YF-93
Republic XF-84H

Bibliography

Dorr, Robert F. and Donald, David. Fighters of the United States Air Force. London: Temple, 1990. ISBN 0 600 55094 X,
Knaack, Marcelle Size. Encyclopedia of US Air Force Aircraft and Missile Systems: Volume 1 Post-World War II Fighters, 1945-1973.. Washington: Office of Air Force History, 1978. ISBN 0-912799-19-6.

McDonnell XF-88 Voodoo Pictures and McDonnell XF-88 Voodoo for Sale.

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Source: WikiPedia