This experimental single-seat interceptor fighter designed by Sydney Camm to meet the requirements of Specification F.20/27, was flown in August 1928 with a 450hp Bristol Jupiter VII radial. Of metal construction with sharply staggered single-bay wings and a twin-Vickers gun armament, the prototype was re-engined with a 520hp Mercury VI in May 1930. It demonstrated a maximum level speed of 325km/h. By this time the F.20/27 specification had prompted Hawker to initiate development of a more advanced fighter as a private venture, and this, owing much to the F20/27, was to emerge as the Hornet in 1929.
F.20/27 Engine: 520hp Mercury VI Max take-off weight: 1429 kg / 3150 lb Empty weight: 977 kg / 2154 lb Wingspan: 9.14 m / 29 ft 12 in Length: 7.17 m / 23 ft 6 in Height: 2.87 m / 9 ft 5 in Wing area: 21.18 sq.m / 227.98 sq ft Max. speed: 325 km/h / 202 mph
The Hind light bomber was one of the types produced for quick delivery to the RAF, based on the Hart and therefore needing little new development, although a number of improvements were introduced as the result of long experience with the Hart.
The first prototype was a modified Hart and first flew on 12 September 1934 at Brooklands.
By the end of 1935 the Hind had started to replace the Hawker Hart as a front line fighter with the RAF. The production total was 528 aircraft, although with the delivery of modern monoplane bombers a number of the final Hinds on the production lines for the RAF were completed as dual-control trainers. Records show that from even the first batch of 20 Hinds, General Aircraft was later to convert nine into trainers.
Nine foreign users of the Hind (new and ex-RAF aircraft) included Latvia, New Zealand, Persia and South Africa.
Engine: 1 x Rolls-Royce Kestrel V, 477kW / 631 hp Max take-off weight: 2403 kg / 5298 lb Empty weight: 1475 kg / 3252 lb Wingspan: 11.35 m / 37 ft 3 in Length: 9.02 m / 29 ft 7 in Height: 3.23 m / 10 ft 7 in Wing area: 32.33 sq.m / 348.00 sq ft Max. speed: 161 kts / 299 km/h / 186 mph @ 16,000 ft Service ceiling: 8045 m / 26400 ft Initial climb rate: 1870.08 ft/min / 9.50 m/s Range: 374 nm / 692 km / 430 miles Armament: 2 x 7.7mm machine-guns, 220kg of bombs Crew: 2 Endurance: 4 h
The Osprey was a two-seat naval fighter-reconnaissance biplane, developed from the Hart but with additional strengthening for catapult launching, folding wings for storage on board ship and naval equipment.
The first prototype flew in 1930 and was eventually followed by 37 Osprey Mk I, 14 Mk II, 52 Mk III and 26 Mk IV production aircraft; the Mk IIs later being modified into Mk IIIs with Fairey Reid propellers and other refinements. A small number of the genuine Mk IIIs were constructed of stainless steel, one of which, according to Hawker records, was exhibited in skeleton form at the 1932 Paris Show. Standard power plant for the Mk Is, IIs and IIIs was the 423kW Rolls-Royce Kestrel IIMS, giving a maximum speed of 257km/h as a landplane. Seaplane Ospreys had twin floats, although an experiment was carried out with one aircraft fitted with a central main float and wingtip stabilising floats. The Mk IV was powered by a 477kW Kestrel V engine.
Ospreys entered service with the FAA in 1932 and eventually flew from aircraft carriers, cruisers and other warships. In 1934 one RAF squadron took delivery of four Ospreys for communications work, and in the same year HMS Sussex went to Melbourne as part of the Centenary celebrations carrying an Osprey. By mid-1935 several ships of the Second Cruiser Squadron of the Home Fleet had been issued with Ospreys and the new cruiser Ajax had received two for service with the Mediterranean Command. These remained in service until 1939. The Swedish vessel Gotland had received Mercury-powered Ospreys, known as Nohabs. These remained operational as naval co-operation aircraft alongside Heinkel He 5s until 1940. Three Ospreys were also delivered to Portugal and Spain, although it is uncertain whether the Spanish aircraft was among the 57 machines sent by Britain to the Republican Air Force during the Civil War.
Osprey Mk III Engine: 423kW Rolls-Royce Kestrel IIMS Max take-off weight: 2245 kg / 4949 lb Empty weight: 1545 kg / 3406 lb Wingspan: 11.28 m / 37 ft 0 in Length: 8.94 m / 29 ft 4 in Height: 3.17 m / 10 ft 5 in Wing area: 31.5 sq.m / 339.06 sq ft Max. speed: 270 km/h / 168 mph Ceiling: 7165 m / 23500 ft
Osprey Mk IV Engine: Rolls Royce Kestrel V, 631 hp Length: 29.331 ft / 8.94 m Height: 10.4 ft / 3.17 m Wingspan: 37.008 ft / 11.28 m Wing area: 338.958 sq.ft / 31.49 sq.m Max take off weight: 4950.2 lb / 2245.0 kg Weight empty: 3404.5 lb / 1544.0 kg Max. speed: 153 kts / 283 km/h Cruising speed: 94 kts / 175 km/h Service ceiling: 25000 ft / 7620 m Wing loading: 14.56 lb/sq.ft / 71.0 kg/sq.m Endurance: 2 h Crew: 2 Armament: 2x cal.303 MG (7,7mm)
The Hawker Hartebeeste (also known as Hartbee or Hartebees) was a version of the Hawker Audax air co-operation aircraft modified for use in South Africa. The first was flown on 1 June 1928, and four (s/n 801 to 804) were produced by Hawker in 1934-35, with another sixty five (s/n 805 to 869) built by Roberts Heights in Pretoria, South Africa from 1937. The main difference between the Hartebeeste and the Audax was a change of engine to the Rolls Royce Kestrel VFP, producing 608hp. The more powerful engine compensated for the addition of some armour around the cockpits.
The Hartebeeste had a short front line career with the South African Air Force. Introduced on 1 January, 1930, two squadrons were equipped with the Hartebeeste when the Italians entered the war on 10 June 1940. The next day the Hartebeeste’s undertook their biggest operation of the war, a large scale attack on Italian positions. Soon after that the Hartebeeste was withdrawn from the front line, and transferred to training and communications units, remaining in service for the rest of the war.
Hawker Hartebeeste Engine: Rolls Royce Kestrel V FP, 600 hp / 453kW Total Length: 29ft 7in / 9.020 m Greatest height: 10 ft 5 in / 3.170 m Wingspan: 37ft 3in / 11.350 m Wing area: 348.000 sqft / 32.330 sq.m Max take off weight: 4787.1 lbs / 2171.0 kg Weight empty: 3150 lbs / 1429.0 kg Max. speed: 153 kts / 283 km/h / 176 mph Service ceiling: 22,000 ft / 6705 m Wing load: 13.74 lbs/sq.ft / 67.00 kg/qm Endurance: 3 h Crew: 2 Armament: 2 x .303 MG (7,7mm), one forward firing and one in aft cockpit plus light bombs or supply canisters under the wings.
When, in 1935, Specification F.9/35 was issued for a two-seat interceptor fighter to replace the Demon, both Hawker and Boulton Paul tendered proposals for aircraft fitted with the Boulton Paul turret mounting four 0.303-in (7,7-mm) machine guns. Hawker’s submission was based on redesign of the Henley light bomber, prototype construction of which had just commenced. Like the Henley, it utilised standard Hurricane outer wing panels. Dubbed Hotspur, the prototype (K8309) of the two-seat fighter was not flown until 14 June 1938, and then with only a wooden mock-up of the turret and with ballast equivalent to the weight of armament. Powered by a 1,030 hp Rolls-Royce Merlin II, the Hotspur proved faster than the competitive Boulton Paul Defiant, but as Hawker and its parent Group were fully committed to production of the Hurricane, no effort was made to bring the prototype Hotspur up to representative Service standard and development was discontinued, the aircraft subsequently being utilised for flap and dive brake development.
Max take-off weight: 3470 kg / 7650 lb Empty weight: 2631 kg / 5800 lb Wingspan: 14.59 m / 47 ft 10 in Length: 11.01 m / 36 ft 1 in Height: 4.37 m / 14 ft 4 in Wing area: 31.77 sq.m / 341.97 sq ft Max. speed: 509 km/h / 316 mph
The Henley was designed to an Air Ministry requirement for a two-seat-high-performance light bomber with good enough performance to be used as a dive bomber for close air support.
The prototype first flew in March 1937.
Despite its promise, its role was changed to that of target towing. Four hundred were ordered, but only 100 Merlin II and 100 Merlin III-engined Henleys were built at the Gloster works. The type proved ill-suited to the task, with many engine failures due to a cooling system which performed best at high airspeeds not suitable for target towing. They ended their short careers towing the larger drogues for training anti-aircraft gun crews. They were withdrawn from service in 1942.
According to Hawker records two Henleys were used as engine test beds for Vulture and Griffon engines and one was tropicalised.
Engine: 1 x Rolls-Royce Merlin II, 1016 hp / 768kW Wingspan: 14.59 m / 47 ft 10 in Length: 11.1 m / 36 ft 5 in Height: 4.46 m / 14 ft 8 in Wing area: 31.77 sq.m / 341.97 sq ft Max take off weight: 3845 kg / 8477 lb Empty weight: 2725 kg / 6008 lb Wing loading: 24.81 lb/sq.ft / 121.00 kg/sq.m Service Ceiling: 8230 m /27000 ft Max. speed: 204 kts / 438 km/h /272 mph Cruising speed: 378 kph Range: 826 nm / 1529 km / 950 miles Crew: 2
British Army co-operation biplane. The Hawker Hector was an 600kW / 805 hp Napier Dagger air-cooled and supercharged powered derivative of the Hawker Hart produced to meet a 1935 specification for a replacement for the Hawker Audax, itself a development of the Hart.
The H type Dagger IIIMS 24-cylinder gave the Hector a distinctive nose profile, while other modifications included an upper wing with straight leading edge, a tail wheel in place of the original skid and a canted ring for the Lewis machine gun in the rear cockpit. A 0.303 in (7.7 mm) Vickers was fitted in the port side of the nose, and two 51 kg (112 lb) bombs could be carried below the lower wings.
The prototype Hector, a converted Hart which first flew on February 14, 1936, was followed by 178 Westland built production machines, the first of which entered service in February 1937.
At the time of a Finnish evaluation, the Hector equipped seven RAF army co-operation squadrons, although the Finns were also advised that it was intended to start replacing the Hectors in RAF service in 1938. The Ilmavoimat / Maavoimat / VL Team expressed considerable disbelief among themselves that in early 1938 the RAF was still flying an aircraft reminiscent of the first World War, particularly in light of the German aircraft designs they were also looking at. Their initial conclusion was that the aircraft was unreliable, obsolete and would be ineffective in its intended role. The Hector was eliminated from the evaluation with no further consideration.
Only a handful of Hectors were ever flown in anger, raiding German positions in occupied France in May 1940. After the Lysanders started entering service, the Hectors were transferred to RAF Auxiliary Air Force squadrons; 613 Squadron used theirs to attack German troops advancing through northern France in May 1940. Two aircraft were lost in combat over Calais, before the squadron was evacuated. Hectors were used by the RAF from 1940 as target-towers, and for towing the General Aircraft Hotspur training gliders. The type was deeply unpopular with ground crews due to the complicated nature of the engine, which had 24 cylinders, with 24 spark plugs and 48 valves, all of which required frequent maintenance.
Britain sold the Irish Free State 13 of the Hectors after the Dunkirk Evacuation. In general they were in poor condition. They were sold by the British War Office to the Irish Free State upon requests for aircraft. The Irish military were wholly unprepared for major warfare, but still relied almost totally on military supplies from Britain. The defence of Ireland was also in the British interest, but with the Battle of Britain raging in the skies, could afford to sell the Irish Government nothing better than the Hector.
Engine: 1 x Napier Dagger III MS “H”, 600kW / 805 hp Max take-off weight: 2227 kg / 4910 lb Empty weight: 1537 kg / 3389 lb Wingspan: 11.26 m / 36 ft 11 in Length: 9.09 m / 29 ft 10 in Height: 3.17 m / 10 ft 5 in Wing area: 32.14 sq.m / 345.95 sq ft Wing loading: 14.15 lb/sq.ft / 69.0 kg/sq.m Max. speed: 163 kts / 301 km/h / 187 mph Ramge: 300 miles Service Ceiling: 7315 m / 24000 ft Armament: 1 x 7.7mm / 0.303in Vickers Mk.V machine-guns (forward firing), one rear-firing 303 in (7.7 mm) Lewis gun mounted in the rear cockpit Bombload: 2 x 51kg bombs Crew: 2
Air Ministry Specification G.4/31 called for a General Purpose aircraft, capable of level bombing, army co-operation, dive bombing, reconnaissance, casualty evacuation and torpedo bombing. The Vickers Type 253 won against the Fairey G.4/31, Westland PV-7, Handley Page HP.47, Armstrong Whitworth AW.19, Blackburn B-7, Hawker PV-4 and the Parnell G.4/31.
One prototype, first flown on 6 December 1934. No production.
Engine: 1 x 690hp Bristol Pegasus IIIM.3 Max take-off weight: 3019 kg / 6656 lb Empty weight: 1693 kg / 3732 lb Wingspan: 12.19 m / 39 ft 12 in Length: 9.09 m / 29 ft 10 in Height: 3.61 m / 11 ft 10 in Wing area: 32.33 sq.m / 348.00 sq ft Max. Speed: 295 km/h / 183 mph Ceiling: 7224 m / 23700 ft Range: 741 km / 460 miles Armament: 2 x 7.7mm machine-guns, 2 x 110kg bombs Crew: 2
Designed to meet the requirements of Specification F.7/30 calling for a single-seat, four-gun day and night fighter, the P.V.3 was flown on 15 June 1934 with a 695 hp Rolls-Royce Goshawk III steam-cooled engine. This was later to be replaced successively by B.41 and B.43 Goshawks. The P.V.3 was structurally similar to the Fury, and two of its four 0.303-in (7,7-mm) machine guns were paired over the engine and the others mounted one each side of the nose. Officially evaluated at Martlesham Heath with the 700 hp B.43 Goshawk, the P.V.3 featured a weighty and vulnerable evaporative cooling system, and further development was not pursued. This was partly as a result of the unsatisfactory cooling system but primarily owing to the rethinking of fighter requirements for the RAF that had meanwhile taken place and the imminent appearance of the Hurricane in consequence.
Max take-off weight: 2118 kg / 4669 lb Empty weight: 1601 kg / 3530 lb Wingspan: 10.36 m / 33 ft 12 in Length: 8.58 m / 28 ft 2 in Height: 3.17 m / 10 ft 5 in Wing area: 26.99 sq.m / 290.52 sq ft Max. speed: 360 km/h / 224 mph
A two-seat fighter version of the Hart would provide additional fire-power from the rear cockpit was proposed and two prototypes were prepared for evaluation by modification of Hart bombers. These were each powered by a 417kW fully supercharged Rolls-Royce Kestrel engine. Each was equipped with two synchronised forward-firing Vickers machine-guns and had the coaming of the rear cockpit modified to provide a maximum field of fire for the Lewis gun operated by the observer/air gunner. Known as Hart Fighters, these were evaluated and a small batch of six was ordered.
In 1932 the fighter received the name Demon. A total of 305 Demons were built, made up of the prototypes/pre-production aircraft, 77 with Kestrel IIS engines (seven as instructional airframes and one fitted with a 477kW Kestrel VI engine under the Hawker report number 475), 155 with 436kW Kestrel VI engines and those for Australia. From late 1936 aircraft coming from the Boulton Paul production line were equipped with a hydraulically operated shield in the aft cockpit and were known as Turret Demons. The segmented metal shield was provided to give the gunner some protection from the slipstream. Many earlier aircraft were modified retrospectively to this standard. In addition to aircraft supplied to the RAF, a total of 64 were produced for the Royal Australian Air Force which procured them as army co-operation fighters each fitted with bomb racks, a message-retrieving hook and other equipment.
RAAF Demon
An initial 16 Demons were ordered in January 1934 to replace Westland Wapitis with Nos 1 and 3 Sqds. Deliveries began in 1935 and 36 more were ordered at the same time for Army co-operation and then another 10 for target towing and training. They eventually served with 7 RAAF squadron, a few remaining until 1942.
RAAF Demon
As a fighter with the RAF the Demon was finally superseded from late 1938 by the Blenheim IF, but a few were used as target tugs until replaced by the Hawker Henley.
Hawker Demon Fighter interceptor, United Kingdom, 1933 Length : 29.593 ft / 9.02 m Height: 10.4 ft / 3.17 m Wingspan : 37.238 ft / 11.35 m Wing area : 348.0 sqft / 32.33 sq.m Max take off weight : 4465.1 lb / 2025.0 kg Weight empty : 3067.2 lb / 1391.0 kg Max. speed : 158 kts / 293 km/h Service ceiling : 27493 ft / 8380 m Wing load : 12.92 lb/sq.ft / 63.0 kg/sq.m Endurance : 3 h Crew : 2 Armament : 3x cal.303 MG (7,7mm)
