The Airco D.H.10 Amiens was a two-engined heavy bomber based on the earlier D.H.3, but that arrived too late to make any contribution to the fighting during the First World War.
Geoffrey de Havilland's first design for a twin engined bomber, the D.H.3, had reached the prototype stage, and had flown in mid-1916. Although its performance wasn't that impressive an order for fifty aircraft was placed at the end of September 1917, but before any of the aircraft could be completed policy changed and the contract was cancelled. The prototype was taken to the Southern Aircraft Repair Depot at Farnborough, where it was dismantled, apparently without orders.
This didn't mark the end of official interest in the D.H.3 design, for in June-July 1917 the Technical Committee of the Air Board was considering adapting it to match a new specification for a two-seat day bomber, although not with any great urgency.
That all changed on 7 July 1917 when the first German bombers appeared in the skies over London. The Air Board found itself faced with the need to retaliate against Germany and no suitable aircraft. One solution was to place an order for the Navy's Handley Page O/400. Another was to order work to resume on the D.H.3, and on 4 August 1917 the board issuled a control for the production of three 'De Hav. 3 (designed to take B.H.P engine)'. By 18 October the new aircraft had been given a new designation, and had become the 'De. Hav. 10'.
The Air Board had great hopes of the D.H.10, and in December 1917 came up with a plan that would have seen 58 squadrons operating the type by the middle of 1919. The new aircraft was to operate in the two-seat fighter-reconnaissance, short-distance day bomber, long-distance photographic, large-calibre gun carrying, long-distance day bomber, long-distance fighter-reconnaissance and long-distance large-calibre gun carrying roles, a range of activities curiously similar to that actually achieved by the de Havilland Mosquito just over twenty years later.
The first prototype D.H.10 made its maiden flight on 4 March 1918. It was very similar to the D.H.3, with the same spruce and ash construction and a similar pusher configuration. It was powered by two 230hp Siddeley Puma engines, the production version of the B.H.P. As on the D.H.3 the lower wing was attached to the fuselage and the engines were suspended between the two wings, although the gap between the engines was wider. The aircraft carried a crew of three – two gunners and the pilot.
In April 1918 the first prototype underwent tests at Martlesham Heath, where as expected its low powered engines meant that it failed to meet its performance demands. A second prototype, powered by two 360hp Rolls Royce Eagle VIII engines was already close to completion and made its first flight on 20 April, but by then it had already been decided that the production version of the D.H.10 would be powered by two 400hp Liberty 12 engines in a tractor configuration. This aircraft received the designation D.H.10 Amiens Mk. III.
The prototype Mk.III reached Martlesham Heath on 28 July 1918, where it recorded a speed of 120mph at sea level while carrying four 230lb bombs. This was followed by the final prototype, which had longer nacelles, horn balanced ailerons and a reduced mainplane sweepback, and was virtually identical to production machines.
Two variants of the D.H.10 appeared in small numbers. The D.H.10A Amiens Mk.IIIA had the engines mounted directly on the lower wing, saving some weight. Five aircraft were given Rolls Royce Eagle VIII engines as the D.H.10C Amiens Mk.IIIC, presumably to test this engine out in case deliveries of the Liberty engine ended.
On 20 March 1918 an order was placed for 600 production aircraft. Two days later another 200 were added and eventually a total of 1,295 were ordered. Of these aircraft only 13 had been accepted by the end of 1918, and only 236 were ever completed, most of them standard D.H.10s.
The first aircraft reached France in mid-September 1918, but the D.H.10 appears to have only made one solitary operational sortie before the end of the First World War when on 10 November Captain Ewart Garland attacked the German aerodrome at Sarrebourg.
Its post-war career was short-lived. No.120 Squadron used the type to provide an air mail service to the British Army of Occupation of the Rhine.
No.97 Squadron converted to the D.H.10 and operated the type in India between August 1919 and 1 April 1920 as No.97 Squadron and to February 1923 after being renumbered as No.60 Squadron.
No.216 Squadron operated the D.H.10 in the Middle East, flying them on the Cairo-to-Baghdad air-mail service until June 1922, when they were replaced by the Vickers Vimy.
Most remaining aircraft were sold off in February 1922.
Engine: Two Liberty 12s
Wing span: 65ft 6in
Length: 39ft 7.5in
Height: 14ft 6in
Tare Weight: 5,750lb
All-up Weight: 9,000lb
Max Speed: 129mph
Service Ceiling: 17,500ft
Endurance: 5hr 45min
Armament: Four 0.303in Lewis guns in twin mountings, front and rear.
Bomb-load: Six 230lb bombs carried internally