Heinkel He 274
He 274 | |
---|---|
Heinkel He 274 | |
Role | High-altitude heavy bomber Parasite aircraft mother ship (post-war French service) |
Manufacturer | Heinkel |
First flight | December 1945 |
Primary user | French Air Force
|
Number built | 2 |
Developed from | Heinkel He 177
|
Variants | Heinkel He 277 |
The Heinkel He 274 was a German heavy bomber design developed during World War II, purpose-designed for high-altitude bombing with pressurized crew accommodation. Due to the Allied advance through Northwest Europe, the prototypes were abandoned at the French factory where they were being built. They were completed after the war by the French and used for high-altitude research.
Background
On 17 November 1938, the owner of the
By April 1939, interest in developing a high-altitude version of the He 177 had arisen, and on 27 April 1939, the first proposal for such an aircraft was presented to Heinkel by his firm's engineering staff.
The Heinkel firm had been working on practical cockpit pressurization methods and hardware for both the A-2, and slightly later A-4 versions (identical to the A-2, except for the fitting of a pair of the later DB 610 coupled engines) from 1940 through the late summer of 1941, when the DB 610-powered A-4's pressurized cockpit in provisional form, almost identical in external appearance to the standard "Cabin 3" He 177A-series production cockpit, was ready for tests and development.[citation needed]
By October 1941, a more developed "He 177H" specification for a high-altitude Heinkel-designed heavy bomber
In conjunction with his request for help from Generalmajor Eccard Freiherr von Gablenz in May 1942, concerning the suitability of aircraft for the Amerikabomber contract competition as that proposal first appeared, Generalfeldmarschall Erhard Milch also received von Gablenz's opinion on the He 177 and its He 274 development, with von Gablenz stating that neither of these Heinkel "heavy bomber" designs had anywhere near the range to conduct a mission approaching the demands of the new contract.[7]
A pair of the early He 177A-0 pre-production prototypes were renamed the He 177 V10 and V11 for the purposes of high-altitude trials and were to be the first to test the A-4 pattern pressurized cockpit design at altitude. Only the V11 was used for the needed research and managed to achieve an altitude of 9,200 m (30,200 ft) on 9 August 1943. Further tests continued through October of that year, before the V10 and V11 were grounded in April 1944.[8]
In February 1943, the same month by which the RLM's first mention of any official status had occurred for design work on an entirely separate,
Development
The first proposal for what would become the He 274 started with six airframe orders for what had been known as the He 177H, which were requested from Heinkel as early as mid-October 1941, all to have four engines in stretched production He 177A-3 fuselages.[11] The main production version had been lengthened by 160 cm aft of the wing's trailing edge for better stability and also used for the A-5 subtype — mated to longer span, four-engined wings.[12] These proposed aircraft were shortly thereafter officially given the airframe project number 8-274 by the RLM; due to the busy Heinkel factory design offices and aircraft manufacturing facilities, this new "He 274" high-altitude bomber was to have its prototypes built in France by the Societe des Usines Farman (Farman Brothers) in Suresnes. Two He 274 prototypes were ordered built in France by the Farman Brothers and four pre-production prototypes by the Heinkel's Heinkel-Nord headquarters at its Rostock-Marienehe (today's Rostock-Schmarl) facility. Farman at Suresnes, began their prototype development.[citation needed]
Work on the requested half-dozen He 274 prototype airframes was leveraged[clarification needed] off Heinkel aircraft production at AIA Breguet, Toulouse where French factories produced Heinkel components and Junkers aviation engines. French production facilities at Toulouse for Heinkel aircraft were severely damaged by Royal Air Force (RAF) air raids on the night of 5/6 March 1944 and again by the US Eighth Air Force on 25 June 1944. This frustrated completion of the French prototypes, as the design work in Germany and Austria had begun by February 1943, on what had emerged as the Heinkel entry in the trans-Atlantic Amerikabomber strategic heavy bomber design competition, the Heinkel He 277. While the RLM-designated 8-277 airframe's design work had been progressing at the Heinkel-Sud facility in Vienna from before that time, the general arrangement "Typenblatt" drawings for the never-completed He 277, with a design influence for the fuselage's geometry from the smaller Heinkel He 219 night fighter, show that it had also adopted many features from the He 274, especially its twin tail.[13] The Heinkel entry for the Amerika Bomber competition would itself end up being cancelled on 20 April 1944, with not one completed airframe to show for it.[14]
Characteristics
Major differences between the He 274 and the
The He 274's advanced, high-altitude cockpit, despite its aforementioned He 177A-like resemblance from an external view, comprised a
Abandoned prototypes
Construction of the two
The He 274 V1 was repaired by
Eventually the V2 flew exactly two years (on 27 December 1947) after the AAS 01A. By this time, the AAS organization had been absorbed into the French
Operators
- France
- French Air Force
Specifications (He 274 V1)
Data from [citation needed]
General characteristics
- Crew: 4 (pilot, second-pilot/navigator/bomb-aimer and two gunners)
- Length: 23.80 m (78 ft 1¼ in)
- Wingspan: 44.19 m (145 ft 0 in)
- Height: 5.50 m (18 ft 0½ in)
- Wing area: 170.00 m2 (1,829.86 ft2)
- Empty weight: 21,300 kg (46,958 lb)
- Max takeoff weight: 38,000 kg (83,776 lb)
- Powerplant: 4× Daimler-Benz DB 603A 12-cylinder inverted-vee engine, 1,750 PS (1,726 hp; 1,287 kW) each
Performance
- Maximum speed: 580 km/h (360 mph) at 11,000 m (36,090 ft)
- Range: 3,440 km (2,137 mi)
- Service ceiling: 14,300 m (46,920 ft)
- Rate of climb: 4 m/s (780 ft/min)
Armament
- Guns: 5 × 13 mm MG 131 machine guns, one in nose and twin guns in single dorsal and ventral Fernbedienbare Drehlafette FDL 131Z remotely operated gun turrets
- Bombs: up to 4,000 kg (8,818 lb) of disposable stores in two internal bomb bays
See also
Related development
- Heinkel He 177
Aircraft of comparable role, configuration, and era
- Heinkel He 277, Heinkel's Amerikabomber contract contender
Related lists
- List of World War II military aircraft of Germany
- List of military aircraft of Germany
- List of WW2 Luftwaffe aircraft prototype projects
References
- ^ "Lexikon der Wehrmacht - Heinkel He 177, He 177B-Reihe". lexikon-der-wehrmacht.de. Retrieved 22 April 2012.
- ^ Griehl & Dressel 1998, p. 14
- ^ Griehl & Dressel 1998, p. 176
- ^ Griehl & Dressel 1998, p.227
- ISBN 9781853103643. Retrieved 29 March 2012.
- ^ Griehl & Dressel 1998, p. 177
- ISBN 1-85310-364-0.
- ^ Griehl & Dressel 1998, p.179
- ISBN 1-85310-364-0.
- ISBN 1-85310-364-0.
- ^ Griehl & Dressel 1998, p.180
- ISBN 1-85310-364-0.
- ISBN 1-85310-364-0.
- ISBN 1-85310-364-0.
- ^ Griehl & Dressel 1998, p.207
- ISBN 1-85310-364-0.
- ISBN 1-85310-364-0.
Sources
- Jane's fighting aircraft of World War II. Studio Books, 1989.
- Green, William. Warplanes of the Third Reich. London: Macdonald and Jane's Publishers Ltd., 1970 (4th Impression 1979). ISBN 0-356-02382-6.
- Griehl, Manfred and Dressel, Joachim. Heinkel He 177-277-274, Airlife Publishing, Shrewsbury, England 1998. ISBN 1-85310-364-0.
- Gunston, Bill & Wood, Tony. Hitler's Luftwaffe. London: Salamander Books Ltd., 1977. ISBN 0-86101-005-1.