Airco DH.9

DH.9
Airco D.H.9
Role Bomber
Manufacturer Airco
Designer Geoffrey de Havilland
First flight July 1917
Introduction November 1917
Retired 1937
Primary users Royal Air Force
Royal Flying Corps

Royal Naval Air Service
South African Air Force

Number built 4,091
Variants Airco DH.9A
Airco DH.9C
Westland Walrus

The Airco DH.9 (from de Havilland 9) – also known after 1920 as the de Havilland DH.9 – was a British bomber developed and deployed during the First World War.

A single-engined biplane, the DH.9 was a development of Airco's earlier and highly successful DH.4; it reused many elements of its processor, which were mated to an all-new fuselage and the BHP/Galloway Adriatic engine, which promised considerable increases in performance. Anticipating its usefulness, the type was ordered in very large numbers for Britain's Royal Flying Corps (RFC) and Royal Air Force (RAF).

Shortly upon entering service, the DH.9's performance proved to be less than satisfactory. The Adriatic engine was both unreliable and failed to provide the expected power, which gave the DH.9 poorer performance than the aircraft it had been meant to replace; the performance deficit was attributed as having been responsible for the heavy losses that it suffered during the conflict, particularly over the Western Front. However, the subsequently-developed DH.9A, which was outfitted with a more powerful and reliable American Liberty L-12 engine, .

Design and development

The DH.9 was designed by de Havilland for the Aircraft Manufacturing Company in 1916 as a successor to the DH.4. It used the wings and tail unit of the DH.4 but had a new fuselage. This enabled the pilot to sit closer to the gunner/observer and away from the engine and fuel tank. The other major change from the DH.4 was the choice of the promising new BHP/Galloway Adriatic engine, which was predicted to produce 300 hp (224 kW) and so give the new aircraft adequate performance to match enemy fighters.[1][2]

By this time, as a result of attacks by German bombers on London, the decision was made to almost double the size of the Royal Flying Corps, with most of the new squadrons planned to be equipped with bombers.[3] Based on the performance estimates for the DH.9 (which were expected to surpass those of the DH.4), and the similarity to the DH.4, which meant that it would be easy to convert production over to the new aircraft, a massive number of orders (4,630 aircraft) were placed for the type prior to the type even flying.

In July 1917, the prototype (a converted DH.4) performed its maiden flight from Hendon Aerodrome, Charing Cross, London.[1] Unfortunately, the BHP engine proved unable to reliably deliver its expected power; the engine having been de-rated to 230 hp (186 kW) in order to improve its reliability. This deficit had a drastic effect on the aircraft's performance, especially at high altitude, with it being inferior to that of the DH.4 it was supposed to replace. This meant that the DH.9 would have to fight its way through enemy fighters, which could easily catch the DH.9 where the DH.4 could avoid many of these attacks.

While attempts were made to provide the DH.9 with an adequate engine, with aircraft being fitted with the Siddeley Puma, a lightened and supposedly more powerful version of the BHP, with the Fiat A12 engine and with a 430 hp (321 kW) Napier Lion engine, these were generally unsuccessful (although the Lion-engined aircraft did set a World Altitude Record of 30,500 ft (13,900 m) on 2 January 1919[4]) and it required redesign into the DH.9A to transform the aircraft.

Operational history

To boost the rate of production, quantity orders for the DH.9 were also placed with Alliance, G & J.Weir, Short Brothers, Vulcan, Waring & Gillow and National Aircraft Factories No. 1 and No. 2.

The first deliveries were made in November 1917 to 108 Squadron RFC and it first went into combat over France in March 1918 with 6 Squadron, and by July 1918 nine squadrons operational over the Western Front were using the type.

The DH.9's performance in action over the Western Front was a disaster, with heavy losses incurred, both due to its poor performance and to engine failures, despite the prior derating of its engine. Between May and November 1918, two squadrons on the Western Front (Nos. 99 and 104) lost 54 shot down, and another 94 written off in accidents.[5] Nevertheless, on 23 August 1918 a DH9 flown by Lieutenant Arthur Rowe Spurling of 49 Squadron, with his observer, Sergeant Frank Bell, single-handedly attacked thirty Fokker D.VII fighters, downing five of them. Captain John Stevenson Stubbs managed 11 aerial victories in a DH9, including the highly unusual feat of balloon busting with one.[6]

The DH.9 was also more successful against the Turkish forces in the Middle East, where they faced less opposition, and it was used extensively for coastal patrols, to try to deter the operations of U-boats.

Following the end of the First World War, DH.9s operated by 47 Squadron and 221 Squadron were sent to southern Russia in 1919 in support of the White Russian Army of General Denikin during the Russian Civil War.[7] The last combat use by the RAF was in support of the final campaign against Mohammed Abdullah Hassan (known by the British as the "Mad Mullah") in Somalia during January–February 1920.[7] Surprisingly, production was allowed to continue after the end of the war into 1919, with the DH.9 finally going out of service with the RAF in 1920.[8]

Following the end of the First World War, large numbers of surplus DH.9s became available at low prices and the type was widely exported (including aircraft donated to Commonwealth nations as part of the Imperial Gift programme).[4]

The South African Air Force received 48 DH.9s, and used them extensively, including against the Rand Revolt in 1922. Several South African aircraft were re-engined with Bristol Jupiter radial engines as the M′pala, serving until 1937.[9]

Civilian use

DH-9 G-AUED modified with a cabin for use as an airliner

Because of the large number of surplus DH.9s available after the war many were used by air transport companies. They provided a useful load carrying capability and were inexpensive. Early air services between London, Paris and Amsterdam were operated by DH.9s owned by Aircraft Transport and Travel. A number of different conversions for civil use were carried out, both by Airco and its successor, the de Havilland Aircraft Company, and by other companies such as the Aircraft Disposal Company.[10] Some radial powered DH.9Js continued in use until 1936.[11]

Variants

Handley Page H.P. 17 showing slots

Operators

Military operators

DH.9 operators
 Afghanistan
 Australia
 Belgium
 Canada
 Bolivia
 Chile
 Estonia
 India

(Part of Imperial Gift)

Greek DH-9
 Greece
 Kingdom of Hejaz
The Kingdom of Hejaz received 9 DH.9s and 2 DH.9Cs between 1921 and 1924. Five remained in existence (although not airworthy) in 1932.[17]
 Ireland
 Latvia
 Netherlands
 New Zealand
 Paraguay
 Peru
 Poland
 Romania
Spain Kingdom of Spain
 South Africa
 Soviet Union
  Switzerland
Turkish DH-9
 Turkey
 United Kingdom
 United States
 Uruguay

Civil operators

 Australia
 Belgium
 Denmark
 Netherlands
 Romania
Spain Kingdom of Spain
 United Kingdom
Bikaner State

Surviving aircraft

DH.9 F1258 at the Musée de l'Air et de l'Espace, Paris Le Bourget

Of the thousands of DH.9s built, only a few have survived to be preserved. F1258 is displayed at the Musée de l'Air et de l'Espace in Paris,[19] with a second DH.9 being preserved at the South African National Museum of Military History,[20] while G-EAQM, the first single-engined aircraft to fly from the United Kingdom to Australia is preserved in the Australian War Memorial at Canberra.[21][22]

The remains of three DH.9s were discovered in India in 2000,[23] one of which is displayed at the Imperial War Museum Duxford, and another in the process of being restored to flying condition.[24]

Specifications (D.H.9 (Puma Engine))

Airco DH.9 drawing

Data from The British Bomber since 1914[8]

General characteristics

Performance

Armament

See also

Related development
Aircraft of comparable role, configuration and era

References

Notes

  1. 1 2 Jackson 1987, p. 97.
  2. ↑ Bruce 1965, p. 3.
  3. ↑ Bruce 2 April 1956, p. 387.
  4. 1 2 3 Jackson 1987, p. 100.
  5. ↑ Mason 1994, p. 84.
  6. ↑ "John Stevenson Stubbs" theaerodrome.com, Retrieved: 1 May 2011.
  7. 1 2 Bruce 13 April 1956, p. 424.
  8. 1 2 Mason 1994, p. 86.
  9. ↑ Jackson 1987, p. 102.
  10. ↑ Jackson 1973, p. 50-52.
  11. ↑ Jackson 1973, p. 56.
  12. ↑ Barnes 1976, pp. 211–213.
  13. ↑ "From Huffman Prairie To The Moon, The History of Wright-Patterson Air force Base" (PDF). WADC/WADD Digital Collection at the Galvin Library, IIT. 1986. pp. 184–186. ISBN 978-0160022043. Archived from the original (PDF) on 20 February 2016. Plans called for the Curtiss Aeroplane and Moto Corporation of Buffalo, New York, to manufacture 4,000 USD-9As. The order was cancelled, however, when Allied victories in France during the summer of 1918 forecast Germany's ultimate defeat...at least four USD-9A airplanes were manufactured at McCook, but none were built by a contractor.
  14. ↑ Bruce 13 April 1956, p. 423.
  15. ↑ Gerdessen 1982, p. 76.
  16. 1 2 Bruce 13 April 1956, p. 425.
  17. ↑ Andersson Air Enthusiast July/August 2004, pp. 39–42.
  18. ↑ Kopański, Tomasz Jan. Samoloty brytyjskie w lotnictwie polskim 1918–1930 (British aircraft in the Polish air force 1918–1930). Bellona, Warsaw. 2001, ISBN 83-11-09315-6, pp. 55–62. (in Polish)
  19. ↑ "DH.9." Musée de l'Air et de l'Espace. Retrieved: 11 April 2008.
  20. ↑ Blake, Arthur."Colours in the Sky." Military History Journal, Vol 1, No 6. June 1970. The South African Military History Society. Retrieved: 11 April 2008.
  21. ↑ Jackson 1987, p. 125.
  22. ↑ "AWM Collection Record: P02270.029." Australian War Memorial, Retrieved: 11 April 2008.
  23. ↑ "In pictures: 'Elephant stable' bomber." BBC News, 21 April 2007. Retrieved: 11 April 2008.
  24. ↑ "DH-9." Historic Aircraft Collection Ltd, Retrieved: 11 April 2008.

Bibliography

  • Andersson, Lennart. "Wings Over the Desert: Aviation on the Arabian Peninsula: Part One Saudi Arabia". Air Enthusiast, No. 112, July/August 2004. pp. 39–43. ISSN 0143-5450.
  • Barnes, C.H. Handley Page Aircraft since 1907. London:Putnam, 1976. ISBN 0-370-00030-7.
  • Bruce, J. M. "Aircraft Profile No. 62: The de Havilland D.H.9". Profile Publications Ltd, 1965.
  • Bruce, J.M. "The De Havilland D.H.9: Historic Military Aircraft: No. 12, Part I". Flight, 6 April 1956. Pages 385–388, 392.
  • Bruce, J.M. "The De Havilland D.H.9: Historic Military Aircraft: No. 12, Part II". Flight, 13 April 1956. Pages 422–426.
  • Gerdessen, F. "Estonian Air Power 1918 – 1945". Air Enthusiast No 18, April – July 1982. Pages 61–76. ISSN 0143-5450.
  • Jackson, A.J. British Civil Aircraft since 1919 Volume 2. London:Putnam, Second edition 1973. ISBN 0-370-10010-7.
  • Jackson, A.J. De Havilland Aircraft since 1909. London: Putnam, Third edition 1987. ISBN 0-85177-802-X.
  • Mason, Francis K. The British Bomber Since 1914. London: Putnam Aeronautical Books, 1994. ISBN 0-85177-861-5.
  • Winchester, Jim, ed. Bombers of the 20th Century. London: Airlife Publishing Ltd., 2003. ISBN 1-84037-386-5.
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