| Horsley | |
|---|---|
 A Hawker Horsley of No. 100 Squadron, RAF | |
| General information | |
| Type | Medium bomber |
| Manufacturer | Hawker Aircraft |
| Primary user | RAF |
| Number built | 124 |
| History | |
| Introduction date | January 1927 |
| First flight | 1925 |
| Retired | 1935 |
| Variants | Hawker Dantorp |
TheHawker Horsley was a British single-enginedbiplanebomber of the 1920s. It was the last all-wooden aircraft built byHawker Aircraft, and served as a medium day bomber andtorpedo bomber with Britain'sRoyal Air Force between 1926 and 1935, as well as the navies of Greece and Denmark.
The Horsley (named after SirThomas Sopwith's home ofHorsley Towers)[1] was originally designed to meetAir Ministry Specification 26/23 for a day bomber powered by a singleRolls-Royce Condor engine.[2] While the specification called for any production aircraft to be of metal construction, Hawker proposed to build the prototype of wooden construction, gradually switching to a metal structure during production. This was acceptable to theAir Ministry, and an order for a single prototype was placed.[3] The first prototype was first flown atBrooklands in March 1925, powered by a 650 hp (480 kW) engine, and was delivered to theAeroplane and Armament Experimental Establishment atMartlesham Heath on 4 May 1925.[1]
Meanwhile, the Air Ministry revised its requirements, producingSpecification 23/25 which increased the required payload from one to two 550 lb (250 kg) bombs.[4] At the same time, it also issued Specification 24/25 for a torpedo bomber, required to carry a 2,150 lb (980 kg)torpedo.[5] The Horsley's ability to cope with the increased loads required to meet these new specifications led to the design being favoured by the RAF, with an initial order of forty aircraft, consisting of ten wooden Mk Is and 30 Mk IIs of mixed metal and wood construction, being placed.[6]
The Horsley was a large single-engined two-baybiplane. It had a crew of two, comprising a pilot and a gunner/bomb-aimer/radio operator, who had a .303 in (7.7 mm)Lewis gun mounted in aScarff ring in the rear cockpit and a prone position for bomb aiming. The rear cockpit was also fitted with dual controls.[7] The payload included two 550 lb (250 kg) bombs, one 1,500 lb (680 kg) bomb or a torpedo weighing 2,800 lb (1,300 kg).
The structure was originally all wood, but before production was complete an all-metal structure was introduced, made in what became the famous Hawker system of metal construction. The three methods of construction were designated: Horsley Mk I for the all-wooden aircraft, Horsley Mk II for the mixed material, and (unofficially) Horsley III for the all-metal aircraft.[8] Some aircraft were fitted with floats.
Two aircraft, known as the Hawker Dantorp and powered by Leopard II engines were sold to the Danish Government. They had a slightly different fuselage, accommodating a third crew member.[9] The Danes also purchased a licence to build a further ten aircraft at the Danish Naval Workshops (Orlogsvaerftet), but these were not built owing to a shortage of funds.[10]
Production aircraft were powered by the Condor IIIA, but the Horsley was also much used as a flying testbed for other engines, including theNapier Lion,Rolls-Royce Buzzard,Rolls-Royce Eagle, theArmstrong Siddeley Leopard radial engine, theJunkers Jumodiesel engine and early versions of theRolls-Royce Merlin.[11]
The first aircraft were delivered toNo 100 (Bomber) Squadron of theRoyal Air Force atDonibristle, Fife, in September 1927, with two more squadrons,No. 15 andNo. 11 Squadrons receiving Horsleys by the end of the year, replacing theFairey Fawn.[12] The Horsleys proved greatly superior to the Fawn, carrying up to three times the bomb load over greater ranges and at higher speeds, while also being agile for their size,[12] and were popular with their pilots.[13]
In October 1928,No. 36 Squadron formed atDonibristle,Fife, Scotland, as a torpedo-bomber squadron. It was transferred toSingapore in 1930, helping to suppress a rebellion inBurma as well as maintaining its torpedo bombing skills. 100 Squadron converted to the torpedo bombing role in 1930 to fill the gap in home-based defences.[14]
The Horsley was chosen to attempt a non-stop flight to India, with a specially modified aircraft, carrying much more fuel and taking off at a weight of over 14,000 lb (6,350 kg) took off fromRAF Cranwell on 20 May 1927, flown byFlight LieutenantsRoderick Carr and L.E.M Gillman. It ran out of fuelen route, however, ditching in thePersian Gulf nearBandar Abbas,Iran. Despite this it had covered a distance of 3,420 mi (5,500 km), which was sufficient to set a newworld distance record, but was beaten in turn within a few hours byCharles Lindbergh, whose solo Atlantic flight between New York and Paris in theSpirit of St. Louis covered 3,590 mi (5,780 km)).[15]
The Horsleys remained in service in the day-bombing role until 1934, with504 Squadron's Horsleys being replaced byWestland Wallaces atRAF Hucknall in March 1934. No 36 Squadron at Singapore retained the Horsely in the Torpedo bomber role until July 1935.[16] The last Horsley, a Merlin-powered testbed flew its final flight atRAE Farnborough on 7 March 1938.[17]
In total, 124 Horsleys were built, including six aircraft for the Hellenic Naval Air Service and the two relatedDantorps built for Denmark.[18]
Data from Hawker Aircraft since 1919[20]
General characteristics
Performance
Armament
Related development
Aircraft of comparable role, configuration, and era
Related lists
