| DH.9A | |
|---|---|
 Airco D.H.9A | |
| General information | |
| Type | Light bomber/General purpose |
| Manufacturer | Airco |
| Primary users | Royal Air Force |
| Number built | 1,997 + 2,400+ as R.1 |
| History | |
| Introduction date | 1918 |
| First flight | March 1918 |
| Retired | 1931 |
| Developed from | Airco DH.9 |
| Variants | Westland Walrus de Havilland DH.15 |
TheAirco DH.9A is a British single-engined light bomber that was designed and first used shortly before the end of theFirst World War. It was a development of the unsuccessfulAirco DH.9 bomber, featuring a strengthened structure and, crucially, replacing the under-powered and unreliable inline 6-cylinderSiddeley Puma engine of the DH.9 with the American V-12Liberty engine.
Colloquially known as the "Ninak" (from thephonetic alphabet treatment of designation "nine-A"), it served on in large numbers for theRoyal Air Force following the end of the war, both at home and overseas, where it was used for colonial policing in the Middle East, finally being retired in 1931. Over 2,400 examples of an unlicensed version, thePolikarpov R-1, were built in the Soviet Union, the type serving as the standard Soviet light bomber and reconnaissance aircraft through the 1920s.
The DH.9A was planned as an improved version of the existingAirco DH.9. The DH.9 was a disappointment owing to its under-performing and unreliable engines, and the DH.9A was to use a more powerful engine to resolve this. As theRolls-Royce Eagle engine used in the successfulDH.4 was unavailable in sufficient quantities, the new American 400 hp (300 kW)Liberty engine was chosen instead.
AsAirco was busy developing theAirco DH.10 Amiens twin-engined bomber, detailed design was carried out byWestland Aircraft. The DH.9 was fitted with new, longer-span wings and a strengthened fuselage structure.[1]
The first prototype flew in March 1918, powered by a Rolls-Royce Eagle as no Liberty engines were yet available.[2] The prototype proved successful, with the first Liberty-engined DH.9A flying on 19 April 1918, and deliveries to theRoyal Air Force starting in June.[3] By the end of the war, a total of 2,250 DH.9As had been ordered, with 885 being built by the end of the year. As it was decided that the DH.9A would be a standard type in the postwar RAF, the majority of outstanding orders were fulfilled, with 1,730 being built under the wartime contracts before production ceased in 1919.
While the existing aircraft were subject to a programme of refurbishment, a number of small contracts were placed for new production of DH.9As in 1925–26. These contracts resulted in a further 268 DH.9As being built. The new production and refurbished aircraft included batches of dual controltrainers, as well as six aircraft powered by 465 hp (347 kW)Napier Lion engines, which were capable of a maximum speed of 144 mph (232 km/h).
The Soviet Union built large numbers of an unlicensed copy of the DH.9A, theR-1. After the production of 20 DH.4 copies, followed by about 200 copies of the DH.9 powered by theMercedes D.IV engine (also designated R-1) and a further 130 powered by theSiddeley Puma (designated R-2), a copy of the DH.9A powered by the M-5 engine, a Soviet copy of the DH.9A's Liberty, entered production in 1924.[4] ThePolikarpov R-4 was a modification of the R-1, with the engine lowered and moved forward by 140 mm (5.5 in) to improve both the forward visibility and the C.G position. The nose shape was improved by fairing and by installing a retractable ventral radiator. Overall length was increased by 389 mm (15.3 in). Landing legs were changed from wood to steel. Testing showed insufficient improvement over the R-1 to justify production but late R-1s incorporated some of the modifications.[5]
The United States also planned to adopt the DH.9A as a replacement for the DH.4. Development work on the Americanization of the aircraft commenced atMcCook Field inDayton, Ohio.[6] Modifications included a new fuel system with increased fuel capacity, revised wings and tail surfaces, and replacement of theVickers machine gun on the port side of the British built aircraft with a Browning machine gun on the starboard side.[7][8] Plans called forCurtiss to build 4,000 modified aircraft, designatedUSD-9A. This order was cancelled with the end of the war and only nine were built by McCook Field andDayton-Wright.[7][8] One McCook aircraft was additionally modified with an enclosed,pressurised cockpit. In 1921, test pilot Lt. Harold R. Harris made the world's first high-altitude flight in a pressurised aircraft in the USD-9A at McCook Field in Dayton, Ohio.[6]
The DH.9A entered service in July 1918 withNo. 110 Squadron RAF, moving to France on 31 August 1918 to serve with the RAF'sIndependent Air Force on strategic bombing missions. Its first mission was against a German airfield on 14 September 1918.[3] A further three squadrons commenced operations over the Western Front before the Armistice, with99 Squadron (also serving with the Independent Air Force) replacing DH.9s, while18 Squadron and216 Squadron replaced DH.4s.[3] Despite the superior performance of the DH.9A over the DH.9, the DH.9A squadrons suffered high losses during their long range bombing missions over Germany.[9] Other squadrons flew coastal patrols fromGreat Yarmouth before the end of the year.
TheUnited States Marine CorpsNorthern Bombing Group received at least 53 DH-9As, and commenced operations in September 1918.[10]
While the squadrons in service at the end of the First World War quickly disbanded or re-equipped in the postwar dis-armament, the DH.9A continued in service as the RAF's standard light bomber, with 24 squadrons being equipped between 1920 and 1931, both at home and abroad.
The first post war operations were in southern Russia during 1919, in support of the "White Army" against theBolsheviks during theRussian Civil War. In September 1919, the RAF personnel were ordered to return home, leaving their aircraft behind.[7] A squadron of DH.9As was deployed toTurkey in response to theChanak Crisis in 1922, but did not engage in combat.[11]
The DH.9A was one of the key weapons used by Britain to manage the territories that were in its control following the collapse of theOttoman Empire following the Great War. Five squadrons of DH.9As served in the Middle East,[12] occasionally carrying out bombing raids against rebellious tribesmen and villages. An additional radiator was fitted under the fuselage to cope with the high temperatures, while additional water containers and spares (including spare wheels lashed to the fuselage) were carried in case the aircraft were forced down in the desert, the DH.9A's struggling under ever heavier loads. Despite this the aircraft served successfully, with the Liberty engine being picked out for particular praise for its reliability ("as good as any Rolls Royce") in such harsh conditions.[13] Some DH.9A aircraft were also transported toIndia to supplement theBritish Indian Army.
At home, the DH.9A continued on in regular RAF service until 1930, also forming the initial equipment of theRoyal Auxiliary Air Force (RAuxAF).
The R-1 and R-2 were heavily used by theSoviet Air Forces through the 1920s as its standard light bomber and reconnaissance aircraft. The Soviets deployed them in support of the ChineseKuomintang forces in theNorthern Expedition against warlords in 1926–27, and against Chinese forces forcontrol of the Chinese Eastern Railway inManchuria in 1929. R-1s and R-2s were also used in support of operations during theBasmachi Revolt in central Asia.[14]
Afghanistan
Canada
Iran
Latvia
Switzerland
A single example, serial numberF1010, survives and is on display at theRoyal Air Force Museum London. The aircraft was completed byWestland Aircraft in June 1918 and was one of 18 DH.9A's assigned toNo. 110 Squadron RAF. It was the thirteenth aircraft, but was given the number "12A" because thirteen wasthought unlucky. The squadron began flying bombing missions in September 1918, and on the 25th, the crew ofF1010 claimed the destruction of a GermanFokker D.VII fighter. The aircraft's fourth and final combat mission was on 5 October when either flak damage or engine trouble forced a landing behind German lines. The aircraft was undamaged by the landing and the crew were taken prisoner.[22]
The aircraft remained in German hands after the war and in 1936 it was put on display at theDeutsche Luftfahrt Sammlung (Berlin Air Museum), one of the museum's substantial collection of World War 1 aircraft. In 1943, it was one of the museum's exhibits that was moved to Czarnikau (nowCzarnkow in Poland) to save them from theAllied bombing of Berlin. The area was captured by Polish forces in March 1945 andF1010 eventually became part of the collection of thePolish Aviation Museum, although it was not put on display and remained in the museum's stores. In 1977, the Polish Aviation Museum exchangedF1010 for aSupermarine Spitfire from the RAF Museum (difficulties caused by theCold War meant nearly nine years were spent negotiating the swap). The RAF Museum completed restoration of the aircraft and put it on display in 1983.[22]
Data fromThe British Bomber since 1914[23]
General characteristics
Performance
Armament
Related development
Related lists
