De Havilland Swallow

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The correct title of this article is de Havilland Swallow. The initial letter is shown capitalized due to technical restrictions.

de Havilland DH 108 Swallow
Image:DH 108 Swallow TG283.jpg
The first DH 108 built - TG283. The torpedo-shaped objects on the wing tips are containers for anti-spin parachutes.
Type	experimental
Manufacturer	de Havilland
Designed by	John Frost
Maiden flight	15 May 1946
Primary user	Royal Aircraft Establishment
Number built	3

The de Havilland DH 108 "Swallow" was a British experimental aircraft designed by John Carver Meadows Frost in October 1945. It was a flying wing designed to evaluate swept-wing handling characteristics at low and high subsonic speeds for the proposed early tailless design of what would later become the Comet airliner. Three examples of the DH 108 were built to the Air Ministry specifications E.1/45 and E.11/45.

The design proved to be deadly; all three experimental aircraft built were lost in crashes that killed their pilots.

1 History
2 Specifications (DH 108 3rd prototype)
- 2.1 General characteristics
- 2.2 Performance
3 References
4 Related content
5 External links

[edit] History

The first DH 108 prototype, TG283, utilizing the de Havilland Vampire fuselage and a 43° swept wing flew on 15 May 1946. Designed to investigate low-speed handling, it was capable of only 280 mph (451 km/h).

The second, high-speed prototype, TG306, with a 45° swept wing with automatic leading-edge slats and powered by a de Havilland Goblin 3 turbojet, flew soon after in June 1946. It was expected to break the air speed record of the day, 616 mph (991 km/h). Unfortunately, on 27 September 1946, the airframe suffered a catastrophic structural failure at Mach 0.9. The pilot, Geoffrey de Havilland Jr., son of de Havilland company owner-designer Geoffrey de Havilland, was killed in the accident.

VW120 was the the third and final prototype. It differed from the first test aircraft in that it featured a more steamlined nose and canopy (lowering the pilot's seat allowed for a more aerodynamic canopy shape to be employed). It first flew on 24 July 1947 flown by John Cunningham, the former nightfighter ace. The following year, on 12 April 1948, it established a new world speed record of 974.02 km/h (604.98 mph) on a 100 km (62 mi) circuit. Then, on 9 September 1948, it exceeded the speed of sound in a shallow dive from 12,195 m (40,000) ft to 9,145 m (30,000) ft.

The third DH.108 was destroyed on 15 February 1950, in a fatal crash near Brickhill, Buckinghamshire, that took the life of its test pilot, Squadron Leader Stuart Muller-Rowland.

Completing the run of bad luck, the first prototype was lost in a crash on 1 May 1950 at Hartley Wintney, killing the pilot, George Genders. By that point, 480 flights had been made by the three Swallows.

The DH 108 was the first British aircraft to exceed Mach 1 and also the first jet-powered aircraft in the world to achieve this landmark velocity, as the earlier Bell X-1 and Douglas Skyrocket were rocket-powered. Tragically, the DH 108 was literally cursed as all three prototypes were lost in crashes, taking with them, three valiant test pilots.

[edit] Specifications (DH 108 3rd prototype)

[edit] General characteristics

Crew: One
Length: 8.17 m (26 ft 10 in)
Wingspan: 11.89 m (39 ft 0 in)
Height: 4.27 m (14 ft 0 in)
Wing area: 30.47 m² (327.86 ft²)
Loaded weight: 4,064 kg (8,940 lb)
Powerplant: 1x de Havilland Goblin 4, 16.67 kN (3,738 lbf) thrust

[edit] Performance

Maximum speed: 1,090 km/h (677 mph)
Service ceiling: 10,800 m (35,425 ft)
Wing loading: 133 kg/m² (27 lb/ft²)
Thrust/weight: 0.42

[edit] References

Davies. R.E.G. and Birtles, Philip J. Comet: The World's First Jet Airliner. McLean, Virginia: Paladwr Press, 1999. ISBN 1-888962-14-3.
McPhee, Andrew. Unreal Aircraft. "Weird Wings - de Havilland DH.108." Retrieved 4 September 2005.
Watkins, David. De Havilland Vampire: The Complete History. Thrupp, Stroud, Great Britain: Budding Books, 1996. ISBN 1-84015-023-8.