Sometimes a change of scene works wonders – for an aircraft, as well as a person. It was the middle of World War One, and the French aircraft company Société Anonyme des Appareils d’Aviation Hanriot had become a successful producer of licence-built Sopwith 1 1/2 Strutter aircraft.
A decision was made to try to break into the market for single-seater fighters; the task was given to Pierre Dupont, who produced a design with many features of the earlier Sopwith aircraft, particularly the ’1 1/2 strut’ (or ‘W’) arrangement of interplane struts; also, the nose and tail sections were typically ‘Sopwith’ . The Hanriot HD.1 was made as light as possible - the wings had main spars of duralumin and ribs of plywood – since the chosen engine was the nine-cylinder Le Rhone 9jb rotary of 120 hp, giving a maximum speed of 115 mph. Weight was a major consideration, and lead to the decision to arm the HD.1 with only one Vickers .303 machinegun, when the standard fighter armament of both sides was at least two machineguns, at this stage of the war. The French did not adopt this highly manoeuvrable fighter to replace the Nieuport 17, as Hanriot had hoped, instead prefering the fast SPAD 7.
Fortunately, the HD.1 was saved from obscurity by two Allied powers, Belgium and Italy. Both the Aviation Militaire Belge, and the Aeronautica del Regio Escercito adopted the HD.1 as their standard fighter of the late war period; the Italian company, Nieuport-Macchi, negotiated a manufacturing licence building 900 examples, many more than the Hanriot concern did, at 125. Tenente Silvio Scaroni (1893 – 1977), the second ranked WW1 Italian ace, had 26 kills – four on the Nieuport 17, the remainder on the HD.1. However, perhaps the most famous exponent of the HD.1 was Willy Coppens, (1892 – 1986), Baron de Houthulst, who was decorated more than 20 times by Belgium, Dahomy, France, Italy, Morocco, Poland, Portugal, Serbia, Tunisia, and the United Kingdom. Coppens had 37 kills, a total which included 27 balloons. Some pilots tried to boost the HD.1′s firepower by installing a second Vickers .303″ machinegun, but the increased weight affected performance markedly. In Coppen’s case, he had an experimental Vickers machinegun of 11 mm calibre fitted to one of his personal aircraft, and found that the weight of fire was greatly increased and the effect, especially against balloons, was just what he had hoped for. Towards the end of the war a small number of French-built HD.2 aircraft (a modified type) were passed to the United States Navy; these were fitted with float undercarriages. Also, Italy sold 16 refurbished examples of the HD.1 to Switzerland, in 1921. These were used by the Fliegertruppe as advanced trainers until 1930; one preserved example still exists, and is on display at Dübendorf, Switzerland.
Here we see a rare, genuine HD.1 (Serial No. 75) in the restored Grahame-White Factory section of the Royal Air Force Museum, Hendon. Used by 1 em Escadrille de Chasse, Aviation Militaire Belge, according to RAF sources it was flown post-war at an international aerobatics championship at Nice, France in March 1922, by no less than Willy Coppens, who despite having lost most of his left leg during the war, strapped his other leg to the rudder bar – and won! It was disposed of in 1934, being put on the Belgian Register as OO-APJ. When the aircraft was seen in a dilapidated state by no-less a person than Richard Shuttleworth, he purchased it for just £15, and registered it as G-AFDX. Restored to flight status, it flew until a 1939 landing accident at Old Warden. Following the death of Richard Shuttleworth during the war, the stored remains were exported to the U.S.A. in 1962, where it was restored, and flown once more.
In 1978, the aircraft was donated to the RAF Museum, Hendon and completely re-built at the Museum’s Restoration Centre at Cardington. Initially displayed in the main museum building at Hendon, (between the SE.5a and Westland Wallace, if I remember correctly), when the magnificent Grade II* Listed Building, the Grahame-White Factory, was restored on the Hendon site, the Hanriot was moved in there along with the bulk of the World War One collection.
The HD.1 is a little-known, but undoubtedly important, aircraft of World War One. We are very fortunate to see this fine example displayed in such an appropriate setting.