Short Gurnard
Encyclopedia
The Short Gurnard was a single-engined two-seat biplane
Biplane
A biplane is a fixed-wing aircraft with two superimposed main wings. The Wright brothers' Wright Flyer used a biplane design, as did most aircraft in the early years of aviation. While a biplane wing structure has a structural advantage, it produces more drag than a similar monoplane wing...
naval fighter
Fighter aircraft
A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...
, built in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
to an Air Ministry
Air Ministry
The Air Ministry was a department of the British Government with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964...
specification in 1929. It failed to win production orders and only two flew.
Design and development
The duralamin framed Short Sturgeon had never been expected to achieve production status, but the Air MinistryAir Ministry
The Air Ministry was a department of the British Government with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964...
were sufficiently impressed with its behaviour on water and in the air to invite Shorts to tender for Air Ministry specification O.22/26, a two-seat fleet fighter. The specification sought a Fairey Flycatcher
Fairey Flycatcher
-See also:-References:NotesBibliography* Mason, Francis K. The British Fighter since 1912. Annapolis, Maryland, USA: Naval Institute Press, 1992. ISBN 1-55750-082-7.* Taylor, H A. Fairey Aircraft since 1915. London: Putnam, 1974. ISBN 0-370-00065-X....
replacement, an aircraft that would spend much time in fleet spotter and reconnaissance roles, though without the third crew member the navy usually thought necessary for the latter task; but it also was to have the speed and rate of climb to catch bombers. It was required to be able to perform as a deck lander or a seaplane, and to be strong enough in either configuration to be launched by catapult. Shorts were advised that their duralumin monocoquue fuselage was not suitable for below deck maintenance. Their tender was rewarded with an order for two prototypes of the S.10 Gurnard.
As a result of the Air Ministry comments, the fuselage of the Gurnard was quite different from Shorts recent series of single-engined monocoques. It was a welded steel tube structure with duralumin detachable panels forward and fabric covering aft. The two separate open cockpits were very close together, the pilot sitting in front just under a visibility cut-out in the trailing edge of the upper wing, raised up for a better view over the nose. A 0.303 in (7.7 mm) Vickers machine gun operated by the pilot was mounted on the decking in front of him, slightly to port. The rear cockpit was fitted with a Lewis gun on a Scarff ring
Scarff ring
The Scarff ring was a type of machine gun mounting developed during the First World War by Warrant Officer F. W. Scarff of the Admiralty Air Department for use on two-seater aircraft...
. The steel fuselage stopped at the rear with an attachment for the only monocoque part of the Gurnard, the empennage-carrying tail cone. The fin and rudder leading edge was rounded, the trailing edge of the horn balanced rudder straight. The latter extended below the fuselage, with additional fixed surface in front of it. These surfaces were fabric covered.
The two Gurnard prototypes had different engines. The Gurnard II, the first to be completed, had a 525 hp (392 kW) Rolls-Royce Kestrel
Rolls-Royce Kestrel
|-See also:-Bibliography:* Erfurth, Helmut. Junkers Ju 87 . Bonn, Germany: Bernard & Graefe Verlag, 2004. ISBN 1-85780-186-5....
IIS supercharged water cooled inline and the Gurnard I a 525 hp Bristol Jupiter X supercharged radial engine. Accordingly, the Gurnard II had a smooth and pointed cowling, with a drum shaped radiator between the undercarriage legs, whilst the radial engine had a narrow chord Townend ring
Townend ring
A Townend Ring is a narrow-chord cowling ring fitted around the cylinders of an aircraft radial engine to reduce drag and improve cooling.-Development:...
, with the rear part of its cylinders visible from the side.
The Gurnard was a single bay biplane. It had straight edged, constant chord wings, the lower one being slightly shorter in span and markedly narrower in chord. Both wings carried dihedral, the upper plane the most. The wings were duralumin structures, fabric covered, with simple, near parallel interplane struts between the spars. The centre section was supported by a pair of struts from the upper fuselage on each side. Long Frise ailerons were fitted to the upper wing only.
The wheeled undercarriage was a simple single axle arrangement, with oleo legs forward to the engine bulkhead and rearward bracing struts to the root of the rear wing spar. There was a rather long tailskid to protect the downward extended fin. The seaplane version used a pair of floats, their low drag profile refined via Schneider Trophy
Schneider Trophy
The Coupe d'Aviation Maritime Jacques Schneider was a prize competition for seaplanes. Announced by Jacques Schneider, a financier, balloonist and aircraft enthusiast, in 1911, it offered a prize of roughly £1,000. The race was held eleven times between 1913 and 1931...
experience, cross braced with a pair of horizontal transverse struts. They were mounted with N shaped struts which sloped strongly outwards from the fuselage.
The Gurnard II, fitted with floats, was the first to fly, taking off from the Medway
Medway
Medway is a conurbation and unitary authority in South East England. The Unitary Authority was formed in 1998 when the City of Rochester-upon-Medway amalgamated with Gillingham Borough Council and part of Kent County Council to form Medway Council, a unitary authority independent of Kent County...
off Shorts' Rochester factory on 16 April 1929. The pilot was John Lankester Parker
John Lankester Parker
John Lankester Parker OBE FRAeS Hon. MSLAE was Chief Test Pilot for Short Brothers from 1918 until his retirement in 1945. He joined Shorts in 1916 as a part-time test pilot and assistant to then Chief Test Pilot Ronald Kemp, having been recommended for the post by Captain, later Admiral Sir,...
. In May both Gurnards flew as landplanes from Lympne
Lympne Airport
Lympne Airport , , was a military and later civil airfield at Lympne, Kent, United Kingdom, which operated from 1916 to 1984. RFC Lympne was originally an acceptance point for aircraft being delivered to, and returning from, France during the First World War...
, where Shorts maintained a base. By early June both aircraft were at RAF Martlesham Heath
RAF Martlesham Heath
RAF Martlesham Heath is a former Royal Air Force airfield in England. The field is located 1½ miles SW of Woodbridge, Suffolk.- RFC/RAF prewar use:Martlesham Heath was first used as a Royal Flying Corps airfield during World War I...
for evaluation against the specification, though they both returned briefly to Shorts for some modifications. The water based testing was done at the Marine Aircraft Experimental Establishment
Marine Aircraft Experimental Establishment
The Marine Aircraft Experimental Establishment was a British military research and test organisation. It was originally formed as the Marine Aircraft Experimental Station in October 1918 at RAF Isle of Grain, a former Royal Naval Air Service seaplane base, to design, test and evaluate seaplanes,...
at Felixstowe
Felixstowe
Felixstowe is a seaside town on the North Sea coast of Suffolk, England. The town gives its name to the nearby Port of Felixstowe, which is the largest container port in the United Kingdom and is owned by Hutchinson Ports UK...
. The Gurnards flew well and met the specifications, but were out-performed by the Hawker Osprey, a close relative of the RAF's established bomber the Hawker Hart
Hawker Hart
The Hawker Hart was a British two-seater biplane light bomber of the Royal Air Force , which had a prominent role during the RAF's inter-war period. The Hart was designed during the 1920s by Sydney Camm and built by Hawker Aircraft...
, so no more Gurnards were produced. Shorts did get a useful order for large numbers of their floats for the Ospreys.
The Gurnard II returned from Martlesham to Rochester in 1931 for conversion into an amphibian. This involved the fitting of a single, central float which carried a pair of wheels using an axle that passed through its top. The wheels were on stubs offset from the axle, so that in one position they were lifted above the water, but rotated through 180o from the pilot's cockpit they reached the ground. A similar, smaller version had been used successfully on the Short Mussel
Short Mussel
The Short S.7 Mussel was a single-engined two-seat monoplane built by Short Brothers to test the performance of their duralumin monocoque floats. Two were built.-Development:...
and on a converted Moth
De Havilland Moth
The de Havilland Moths were a series of light aircraft, sports planes and military trainers designed by Geoffrey de Havilland. In the late 1920s and 1930s they were the most common civil aircraft flying in Britain and during that time every light aircraft flying in the UK was commonly referred to...
. The central float was again mounted with a pair of N shaped struts, now vertical. There was a pair of outboard stabilising floats beyond the interplane struts, each mounted on a pair of vertical legs. The floats were each directly braced with a pair of struts to the interplane struts from below, and from above by a pair of struts from the top of the rear interplane strut to the tops of the legs. It first flew in this configuration in June 1931 and returned to Martlesham within the month, appearing in that year's Hendon RAF Display.
After that it came back for while to Rochester, where it was used to investigate cooling of the Kestrel engine. At this time it was flying with a tall pillar radiator between fuselage and float. In October the float was modified, and later that month six flights were made between Lympne airfield (land) and the Medway (water) in a total of 90 minutes. In December it returned to Felixstowe, where it served as an engine and cooling system test-bed.