RAF´s pre-war aircrafts

[gekho]

The Bluebird L.1 was initially designed as a competitor in the Lympne light aircraft trials to be held in September 1924 for a low-powered two-seater, fitted with a 67 in³ (1,100 cc) Blackburne Thrush three-cylinder radial engine. The Bluebird was a wooden single-bay biplane, with folding wings and was fitted with a single side-by-side cockpit. Although first flying in 1924, it was not finished in time to compete in the 1924 competition. It was realised that the machines that resulted from the 1923 and 1924 light aircraft trials were too low-powered for serious use, the Daily Mail sponsored a similar competition in September 1926, this time allowing the use of heavier and more powerful engines. The prototype Bluebird was then fitted with an Armstrong Siddeley Genet radial engine and dual controls for entry into the competition. Interest in the Bluebird following the competition and its success in the 1926 Grosvenor Cup air race, which it won, resulted in Blackburn manufacturing a batch of 13 production aircraft, known as the L.1A Bluebird II, which were similar to the prototype, and a further seven modified L.1B Bluebird III. The Bluebird formed the basis for the all-metal Blackburn Bluebird IV.

The wooden Bluebirds were mainly used by flying clubs, and were heavily used, but several were quickly written off, with only three surviving for more than four years. One Bluebird II was fitted with floats and another, the Bluebird III prototype, was fitted with an ADC Cirrus engine as a testbed for the Bluebird IV. The last wooden Bluebird was destroyed in a fire-fighting demonstration in 1937

 

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During the early 1920s, the tactical philosophy of the Royal Air Force for the interception of bomber forces stressed the value of standing fighter patrols: this was seen as the only practical method, before the advent of radar and the possibility of a scrambled take-off and rapid climb to the right location, of ensuring the interception and destruction of the bomber forces before they could reach their targets. This philosophy placed emphasis on fighters with long endurance and the ability to carry radio equipment, so that any pilot who spotted a bomber formation could report the fact to his ground controller and neighbouring fighters, and resulted in machines such as the Armstrong Whitworth Siskin and Gloster Gamecock. By 1924 the advent of the Fairey Fox high-speed day bomber, with its powerplant of one Curtiss D-12 water-cooled V-12 engine, was starting to persuade the RAF that this tactical philosophy was outdated: with its powerful engine and trim lines, the Fox could both outpace and outclimb current fighters. The RAF was also coming to an appreciation of the fact that standing patrols were wasteful of fuel, airframe and engine hours, and pilot endurance. The new tactical philosophy adopted by the RAF emphasised the use of fighters that were fast and could climb rapidly for the timely engagement of targets that had been spotted by ground observers.

This new philosophy was embodied in the Air Ministry's F.17/24 requirement for a fast-climbing fighter to be powered by the Rolls-Royce Falcon X (later Kestrel) water-cooled V-12 engine. Yet current water-cooled engines such as the Falcon were heavy as well as powerful, and Captain Frank Barnwell and Roy Fedden, chief designers of Bristol's aircraft and engine divisions respectively, therefore suggested replacement of the water-cooled V-type engine by an air-cooled radial of the type that was the particular speciality of the Bristol aero engine division. The Air Ministry appreciated the sound nature of Bristol's criticism and revised the F.17/24 requirement into the F.9/26 requirement for a standard day/night fighter with a powerplant based on one engine of either the water-cooled V-type or air-cooled radial variety. The Fleet Air Arm had a requirement for a fighter at this time, and Barnwell therefore prepared the Type 102 design for a fighter based of the Type 99 Badminton racing biplane of 1925.

This Type 102 was to be powered by the new and extremely promising Bristol Mercury radial piston engine, and was offered to the RAF as the Type 102A with wheeled landing gear and to the FAA as the Type 102B with alternative twin-wheel landing gear for carrierborne use or twin-float alighting gear for seaplane use. At this time the Air Ministry revived its demand for a fast-climbing day interceptor, and Barnwell thus worked in parallel on two types: the day/night fighter to the F.9/26 requirement was the Type 105 that was an improved version of the Type 102 with the powerplant of one Bristol Jupiter VII air-cooled nine-cylinder radial engine rated at 440 hp (328 kW), and the interceptor to the F.20/27 requirement was the Type 107 Bullpup with the powerplant of one Mercury IIA air-cooled nine-cylinder radial engine rated at 480 hp (358 kW). Bristol thought that the Type 107 was the more important of its two designs, and it was clear that this would face stiff competition from four other prototypes ordered from Gloster, Hawker, Vickers and Westland. It should also be noted that the Air Ministry had expressed a preference for the successful F.9/26 contender to be powered by the Rolls-Royce F.XI water-cooled V-12 engine, so Bristol decided to build its Type 105 prototype as a private venture outside the main F.9/26 competition. The two Bristol designs had much in common, and in their original forms were each planned with an equal-span biplane wing cellule: this was later revised to a virtually sesquiplane layout with a lower wing of less span and chord than the upper wing.

The Type 107, it is worth noting, first flew in April 1928 with the powerplant of one Jupiter VI engine as the Mercury IIA was not yet ready, and was evaluated in 1929 after the Mercury IIA had been installed. In its definitive form, the Type 107 spanned 30 ft 0 in (9.14 m) and had a maximum take-off weight of 2,850 lb (1293 kg): the combination of this smaller size and lesser weight made the aeroplane both faster and handier than the Bulldog, but the Air Ministry sensibly decided that its superiority was not sufficient to warrant a change in production.

The Type 105 was of bolted high-tensile steel construction covered with fabric except on the forward fuselage, which was completed with light alloy panels. The fuselage was of basically circular section over its forward section becoming oval in section farther aft, and carried the flying surfaces, fixed tailskid landing gear including a main unit of the through-axle type, and the powerplant. This last was installed in the tapered nose with the cylinder heads protruding into the airflow, and drove a two-blade wooden propeller of the fixed-pitch type with a spinner that continued the lines of the forward fuselage for a good nose entry. The flying surfaces comprised a cantilever tail unit and a staggered single-bay wing cellule. The flat upper-wing centre section was of narrow chord and thin section, and supported above the fuselage by the normal arrangement of cabane struts: this centre section supported the dihedralled outer panels of the upper wing, which were of thicker section and greater chord, each carried a fuel tank and an outboard aileron, and separated from the smaller lower-wing panels by a pair of interplane struts on each side; the wing cellule was completed by the standard arrangement of flying and landing wires.

 

[gekho]

The Type 105 or Bulldog Mk I prototype recorded its maiden flight on 17 May 1927 and soon revealed a pleasing combination of good handling and adequate performance, the latter including a maximum speed of 150 kt (173 mph; 278 km/h) at optimum altitude. Though officially it was flown outside the F.9/26 competition, the Type 105 was clearly superior to three of the official contenders (the Armstrong Whitworth A.W.XVI, Boulton Paul P.33 Partridge, and Gloster SS.19) and thus rivalled only by the Hawker Hawfinch, and the Air Ministry thereupon ordered a single Type 105A prototype for official evaluation as the Bulldog Mk II. This prototype recorded its maiden flight in January 1928, and differed from the Bulldog Mk I mainly in having an extended rear fuselage that increased overall length from 23 ft 0 in (7.01 m) to 25 ft 0 in (7.62 m), and a slightly revised wing cellule that reduced span from 34 ft 0 in (10.36 m) to 33 ft 10 in (10.31 m) and area from 307.00 sq ft (28.52 m²) to 306.50 sq ft (28.50 m²). The competition between the two types was particularly hard fought, but the Air Ministry in June 1928 selected the Bulldog Mk II as the winner largely on the grounds that it was of all-steel construction and therefore more durable than the Hawfinch, which was of steel and light alloy construction.

An initial order was placed for 25 aircraft, and these machines were delivered between May and October 1929, entering service with Nos 3 and 17 Squadrons as replacements for the Hawker Woodcock fighters that these two units had flown largely in the night-fighter role. The Air Ministry then ordered a second batch of aircraft, and these 23 machines were delivered in 1930 as the equipment of Nos 17 and 54 Squadrons. Other than those above, the details of the Bulldog Mk II included an empty weight of 2,200 lb (998 kg), maximum take-off weight of 3,490 lb (1583 kg), maximum speed of 155 kt (178 mph; 286.5 km/h) at 10,000 ft (3050 m), and service ceiling of 29,300 ft (8930 m). The Bulldog was already acquiring an excellent reputation for handling and performance, and this combined with the type's reputation for structural reliability and the low cost of its well-proved Jupiter engine to attract export orders. Some 12 aircraft with an armament of two Oerlikon machine guns and the powerplant of one Gnome-Rhône (Bristol) Jupiter VI or Gnome-Rhône 9Asb engine (10 and two aircraft respectively) were delivered in 1929 and 1930 to Latvia, which later sold 11 of them to Spain. Another 12 were delivered to Estonia in 1930 with the powerplant of one Gnome-Rhône (Bristol) Jupiter VI engine, and smaller orders were placed by Australia(eight aircraft delivered in January 1930 with the powerplant of one Jupiter VIF engine), Sweden (three aircraft used for evaluation of the Bulldog), Siam (two aircraft delivered in January 1930 with the powerplant of one Jupiter VII engine), the USA (two aircraft delivered to the US Navy in 1929 and 1930 for trials purposes, in the course of which the first machine was lost as a result of aileron flutter and separation in a terminal-velocity dive), and Japan (one aeroplane with the powerplant of one Nakajima [Bristol] Jupiter VII engine for evaluation). In Japan the Bulldog was extrapolated with Bristol assistance into the Nakajima JSSF with the Jupiter VII engine, but this variant's two prototypes did not pave the way for any production.

In May 1930 the Air Ministry ordered another 92 fighters to the improved Bulldog Mk IIA standard with the Jupiter VIIF engine rated at 440 hp (328 kW) for take-off and 520 hp (388 kW) at 10,000 ft (3050 m), revised wing spars, a measure of local strengthening to permit operation at higher weights, a redesigned oil system, and a wider-track main landing gear unit carrying larger wheels with Bendix tyres and wheel brakes; the aircraft were later revised with a modified fin and a tailwheel in place of the original tailskid. The other details of the Bulldog Mk IIA included the armament of two 0.303 in (7.7 mm) Vickers Mk II or Mk IIN fixed forward-firing machine guns with 600 rounds per gun together with four 20 lb (9.1 kg) bombs on a rack under the port lower wing, span of 33 ft 10 in (10.31 m) with area of 306.50 sq ft (24.47 m²), length of 25 ft 0 in (7.62 m), height of 9 ft 10 in (3.00 m), empty weight of 2,412 lb (1094 kg), maximum take-off weight of 3,530 lb (1601 kg) later increased to 3,660 lb (1660 kg), maximum speed of 154.5 kt (178 mph; 274 km/h) at 10,000 ft (3050 m) declining to 141 kt (162 mph; 261 km/h) at 20,000 ft (6095 m), climb to 20,000 ft (6095 m) in 14 minutes 30 seconds, service ceiling of 29,300 ft (8930 m), and range of 304 nm (350 miles; 563 km).

The aircraft were delivered between October 1930 and May 1931, and by the end of 1931 some 10 of the RAF's 13 home-based fighter squadrons were equipped with the Bulldog: these units were Nos 3, 17, 19, 23, 29, 32, 41, 54, 56 and 111 Squadrons. Orders were later placed for an additional 162 examples of the Bulldog Mk IIA, which was numerically the most important British fighter of the early 1930s. Yet the type was essentially an interim fighter whose performance was hampered by its use of a modestly rated radial engine in an uncowled installation: the advantages of this powerplant were its reliability and low purchase cost, but by the early 1930s its disadvantages were a basic lack of potential for development into significantly higher-rated forms and the emergence of powerful V-12 engines whose low-drag installations offered the possibility of much improved overall performance. Thus the replacement of the Bulldog began as early as 1933, when No. 23 Squadron converted to the Hawker Demon. The replacement process was slow, however, and it was June 1937 before the last unit, No. 3 Squadron, relinquished its Bulldogs.

 

[gekho]

Bristol was not content to let the Air Ministry dictate the whole of the Bulldog's development, and thus pursued its own course of active development that served to improve the breed as a whole and also allow the evaluation of several types of powerplant. The last Bulldog Mk II was thus retained by Bristol as a development 'hack'. This machine was first flown with a geared Mercury IV engine, and further development saw use of the Mercury III engine driving a four-blade propeller and then the Gnome-Rhône (Bristol) Jupiter VI engine. This latter powerplant was intended for an export version for countries in which the licence-built version of the Jupiter held sway, and it was while practising for a demonstration tour to these countries that a Bristol pilot was forced to bale out of the machine after it had suffered a damaged rudder during a flick roll. A replacement machine was built, and this was engined successively with the Gnome-Rhône 9Asb engine (a developed version of the French-built Jupiter), Mercury IVS2 engine, Bristol Perseus IA air-cooled nine-cylinder radial engine, and finally the Mercury VIS2 engine driving a three-blade Hamilton Standard propeller. Further evolution of the basic airframe resulted in the Bulldog Mk IIIA, which was produced as a private venture to compete with the Gloster SS.19B for an order as replacement for the Bulldog in RAF service.

The Bulldog Mk IIIA first flew in September 1931 with a powerplant of one Mercury IVA radial engine that was later replaced by a Mercury IVS2 radial engine rated at 560 hp (417.5 kW) and enclosed in a short-chord ring cowling of the Townend type. Other than its higher-rated powerplant, the Bulldog Mk IIIA could be distinguished from the Bulldog Mk IIA by its deeper wing sections, which were of the biconvex type and allowed the fuel tanks to be accommodated entirely within the wing section, its lower wing of reduced chord to provide the pilot with improved downward fields of vision, its single rather than double flying wires, its deeper rear fuselage that provided additional stiffness, and spatted main wheels. The Bulldog Mk IIIA was considerably faster than the Bulldog Mk IIA, recording a maximum speed of 181 kt (208 mph; 335 km/h) at 15,000 ft (4570 m), but was lost in a crash during March 1933. Bristol built a second Bulldog Mk IIIA prototype, but no order for the type was forthcoming as the Air Ministry preferred the SS.19B that was ordered into production as the Gauntlet. The second Bulldog Mk IIIA was then converted in 1934 into the Bulldog Mk IV prototype. This was intended to provide Bristol with a contender for the F.7/30 requirement, which called for a four-gun day/night fighter. Bristol again found itself pitted against Gloster for a production contract, and as a result of the two types' official evaluation the SS.37 was preferred to the Bulldog Mk IV and ordered into production as the Gladiator. This was hardly a surprising decision as the Bulldog Mk IV could achieve a maximum speed of only 194.5 kt (224 mph; 360.5 km/h) by comparison with the S.S.37's figure of 217 kt (250 mph; 402 km/h).

This was not quite the end of the road for the Bulldog, however, for the Finnish air force was highly impressed by the Type 105's combination of great ruggedness, considerable agility and adequate performance. In December 1933, therefore, the Finnish government placed an order for 17 Bulldog Mk IVA fighters with the powerplant of one Mercury VIS2 engine enclosed in a long-chord cowling that transformed the looks of this purposeful aeroplane. The order was complicated by the fact that Finland lay in the franchise area for French-built versions of Bristol engines, and it was January 1935 before the 17 fighters were delivered. Some 10 of these aircraft were still operational with the Finnish air force in November 1939 as the equipment of HLeLv 26 (26th Fighter Squadron) of the Lentorykmentti 2 (2nd Aviation Regiment): the aircraft were credited with the destruction of five Soviet warplanes, but were retired from first-line service in January 1940, when they were replaced by Gladiators. The aircraft were then flown as trainers for a short time.

At the end of 1931, one of the 100 aircraft on order as the RAF's second batch of Bulldog Mk IIA fighters was retained for conversion as the Type 124 tandem-seat trainer, and as such became the prototype Bulldog TM (Training Machine). This prototype was evaluated during 1932 and the Central Flying School found it acceptable. There followed an initial production batch of 17 Bulldog TM aircraft that served initially with the CFS and the Coastal Area at Leuchars in Scotland. Production of the Bulldog TM eventually reached 59, allowing the type to serve additionally with six RAF squadrons, where they served as conversion trainers, the RAF College at Cranwell in Lincolnshire, and a number of flying training schools including No. 4 FTS at Abu Sueir in Egypt, which was the only overseas unit to have Bulldogs as a part its its establishment. Some of these aircraft remained operational to 1939, and the details of the Bulldog TM included the powerplant of one Jupiter VIFH engine, span of 34 ft 2 in (10.41 m) with area of 309.00 sq ft (28.71 m²), length of 25 ft 3 in (7.70 m), height of 8 ft 9 in (2.67 m), empty weight of 2,200 lb (998 kg), maximum take-off weight of 3,300 lb (1497 kg), maximum speed of 146 kt (168 mph; 270 km/h) at optimum altitude, and service ceiling of 28,000 ft (8535 m). The Bulldog TM was also used as the basis for a testbed in which air-cooled engines as diverse as the Alvis Leonides nine-cylinder radial, Armstrong Siddeley Cheetah seven-cylinder radial and Napier Rapier H-16 units were tested.

Source: http://www.cmchant.com/the-bristol-bulldog-fighter-plane

 

[gekho]

The outstanding performance of the Fairey Fox day bomber, undoubtedly came as something of a shock both to Fairey's competitors and the Air Ministry. As a result the Air Ministry Specification 12/26 for a new light bomber required an improvement upon the performance of the Fox. Hawker's submission for this requirement, which eventually became known as the Hart, was evolved in conjunction with Rolls-Royce, and when submitted in late 1926 proved sufficiently attractive for construction of a prototype to be authorised. Sidney Camm's design utilised what became known in later years as 'Hawker's patent metal construction system', a lightweight and robust structure with fabric covering. From Rolls-Royce came a new engine - known then as the F.XI, a development of the Falcon engine -which had weight-saving six-cylinder monoblocs instead of individual cylinders.

The airframe design was that of an uncluttered single-bay biplane, the fuselage nicely streamlined, very much a conventional Hawker tail unit, and robust fixed landing gear with tailskid. The biplane wings were of unequal span, the lower wing of constant chord and with a straight leading edge. The upper wing, however, was slightly swept back - a useful recognition feature - and incorporated the ailerons and Handley Page leading-edge slots. The prototype was flown for the first time in late June 1928 in the hands of Flt Lt Bulman and was subsequently flown in competitive evaluation against the Avro Antelope and Fairey Fox II. With superior performance of the Hart confirmed, 15 pre-production aircraft were ordered initially for development and familiarisation, and the first 12 of these entered service with the RAF's No 33 (Bomber) Squadron in late 1929 or January 1930 and one was sent for trials in India. Once again, as with the Fairey Fox which was introduced into service in 1926, a new day bomber was to cause acute embarrassment to the fighter squadrons.

In RAF service the Hart was to prove itself one of the most adaptable aircraft of its era, resulting in a number of variants. These included the Hart Trainer (483 built, not including conversions of other models); Hart C communications aircraft; and tropicalised versions known as the Hart India and Hart Special. A version was built for the Royal Navy, serving both with wheeled and float landing gear, and this was designated Hawker Osprey. In addition Harts were built for overseas customers which included Estonia, Sweden (also licence-built 42 Pegasus-engined Harts) and Yugoslavia, while ex-RAF aircraft eventually went to South Africa, Egypt and Southern Rhodesia.

Harts remained in service with the RAF on the North-West Frontier in India until displaced by Bristol Blenheims in 1939. Some Royal Navy Ospreys were used for target towing and training until 1940, but so far as is known the last in operational service was a Hart used by the South African Air Force well into World War II. Most extensively built between-wars British military aircraft, a total of 952 had been constructed when production ended in 1937, with Armstrong Whitworth, Gloster and Vickers acting as sub-contractors. Hawker records also refer to a civil-registered Hart, first flown on 15 September 1932 and known as the Hart II. This was powered in succession by a Kestrel IIS, Kestrel VI and Kestrel XVI, with the latter having an all-up weight of 2,109kg. It was used for demonstrations at air displays and for taking air-to-air photographs of Hawker aircraft, accumulating 627 flying hours in these roles from August 1933.

 

[gekho]

The rapidly changing world of the 1930s forced the British government to take stock of its defences in relation to the growing military capability of Germany. In 1933 Winston Churchill warned Parliament of Germany's latest path and by 1935 expansion programmes for the British armed forces had been agreed. 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 in fact a modified Hart and first flew on 12 September 1934 at Brooklands. Production covered no less than 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, a new role which many were eventually to fulfil. 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.

Sources: HAWKERHIND.co.uk Hawker Hind - light bomber, trainer

 

[gekho]

Reflecting the design concept of British flying-boats that had originated in the 1920s, the Sarò London twinengine biplane was an all-metal aircraft with fabric-covered wings and tail, and a metal-skinned hull. The type served with RAF Coastal Command during the first two years of World War II. Designed to Air Ministry Specification R. 24/31, the prototype first flew in 1934 with two 559kW Bristol Pegasus III radiais, the engines being mounted on the top wing to be well clear of spray while taking off and landing; the prototype went on to serve for periods between 1934 and 1936 with Nos 209 and 210 Squadrons at Felixstowe and Gibraltar. Production deliveries started in March 1936 with Pegasus III engines, but from the eleventh aircraft the Pegasus X was fitted and the aircraft's designation changed to London Mk II, this variant equipping Nos 201 and 204 Squadrons in 1936 at Calshot and Mount Batten repectively. In 1937 they joined No. 202 Squadron at Kalafrana (Malta) and No. 228 Squadron at Pembroke Dock respectively. By the outbreak of war in September 1939 Londons still equipped No. 201 Squadron, then at Sullom Voe in the Shetland Islands, and No. 202 Squadron still at Gibraltar, while No. 240 Squadron had re-equipped with Londons in July 1939 and was stationed at Invergordon, These flyingboats carried out sea patrols over the North Sea and the Mediterranean, some aircraft being fitted with a large dorsal fuel tank to increase their range. Bombs, depth charges and (occasionally) mines up to a total weight of 907kg could be carried under the lower wing roots. Indeed, the old biplanes undertook a considerable share of the patrol work over the North Sea, keeping watch for the likely breakout into the Atlantic by German surface and submarine raiders as well as the return to German port by blockade runners. Gradually maritime reconnaissance aircraft such as the Lockheed Hudson came to assume these responsibilities while Short Sunderland flying-boats equipped the squadrons flying over the Atlantic and Mediterranean. The Londons were replaced on No. 201 Squadron in April 1940, followed two months later by those on No. 240 Squadron. Only No. 202 Squadron continued to fly Londons at Gibraltar until June 1941.

Source: Saunders-Roe A.27 London Saro A.27 London Saunders-Roe A.27 London - flying boat

 

[gekho]

The Hawker Demon was a two seat fighter aircraft developed from the Hawker Hart light bomber. When that aircraft had first flown in 1928, it was faster than every fighter in RAF service. The logical assumption was that any potential enemy would also be able to produce bombers with the same speed. It was thus essential to produce a fighter capable of catching the Hart. The aircraft that would achieve this was the Hawker Fury, the first of a new breed of interceptor fighter. However, Hawker also produced the Demon, a fighter based on the Hart. The resulting aircraft was very similar to the Hart. However, it was powered by the supercharged Kestrel IIS, which gave it better performance at high altitudes than the Hart. The first prototype Demons were produced by modifying production Harts during 1930. At first the new aircraft was known as the Hart Fighter, being renamed the Demon in July 1932. Six Hart Fighters were produced by May 1931, when they entered service with one flight of No. 23 Squadron. The aircraft was ordered into full production, entering full service in 1933. In all 305 Demons were produced, 232 of them for the RAF.

The Demon was not a great success as a fighter. The speed of the aircraft was such that the rear gunner had great difficulty manoeuvring the gun against the slipstream produced at high speeds. In response the Demon was given a basic Frazer-Nash turret. This consisted of a protective shield, hydraulically powered, which much improved the rear gunner's accuracy. However, when the turret was pointed to the side, it badly affected the accuracy of the two fixed guns. No 23 Squadron became the first full Demon squadron in April 1933. Eventually the type equipped seven regular squadrons and five squadrons of the Auxiliary Air Force. Four of these squadrons saw service overseas at the time of the Abyssinian crisis of 1935-6, something that distinguishes the type from other British fighter aircraft of the period. The Demon remained in front line service until late 1938. At that point the remaining Demon squadrons received the Bristol Blenheim IF night fighter.

Source: Hawker Demon

 

[gekho]

The Supermarine Scapa was an improved version of the Southampton flying boat, developed after Supermarine was taken over by Vickers, and using technology developed for the Schneider races. Unlike most military aircraft of the period it was not developed to satisfy an existing Air Ministry specification, but as a private venture. Supermarine then offered to produce the prototype Scapa (then known as the Southampton IV) in place of the final Southampton II on order. After the successful trials of the prototype another fourteen production Scapas were ordered, before production switched to the larger Stranraer. The Scapa was essentially a refined version of the Southampton II. It was powered by a pair of Rolls Royce Kestrel engines, which were mounted in streamlined nacelles that were positions below the upper wing. The wings themselves were of the same length as on the Southampton, but were of an improved design, and used less drag inducing struts and more wire bracing. The hull was a cleaner version of that on the Southampton II, and was of all-metal construction. The open tandem cockpits of the earlier aircraft were replaced by an enclosed side-by-side cockpit for the pilots, while the other crew positions remained the same. The Scapa used a twin rudder tail, similar in shape to the triple rudder tail of the Southampton.

The Scapa was much faster than the Southampton (141mph compared to 95mph) and had a better maximum range. It entered service with No.202 Squadron at Malta in May 1935, and was then taken on a series of long range cruises around the Mediterranean and African coasts. The Scapa was also used by Nos. 204 and 240 Squadrons in home waters. It remained in service until 1939, although had been replaced by the start of the Second World War.

Source: Supermarine Scapa

 

[gekho]

The Horsley (named after Sir Thomas Sopwith's home of Horsley Towers) was originally designed to meet Air Ministry Specification 26/23 for a day bomber powered by a single Rolls-Royce Condor engine. 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 the Air Ministry, and an order for a single prototype was placed. The first prototype was flown in March 1925, powered by a 650 hp (485 kW) Condor III engine, and was delivered to the Aeroplane and Armament Experimental Establishment at Martlesham Heath on 4 May 1925. Meanwhile, the Air Ministry revised its requirements, producing Specification 23/25 which increased the required payload from one to two 551 lb (250 kg) bombs. At the same time, it also issued Specification 24/25 for a torpedo bomber, required to carry a 2,150 lb (975 kg) torpedo. The Horsley's ability to cope with the increased loads required to meet these new specifications lead to the design being favoured by the RAF, with an initial order of forty aircraft, consisting of 10 wooden Mk Is and 30 Mk IIs of mixed metal and wood construction, being placed.

The first aircraft were delivered to No 100 (Bomber) Squadron of the Royal Air Force in September 1927, with two more squadrons, No. 15 and No. 11 Squadrons receiving Horsleys by the end of the year, replacing the Fairey Fawn. 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, and proving popular with its pilots. In October 1928, No. 36 Squadron formed at Donibristle, Fife, Scotland as a torpedo-bomber squadron. It was transferred to Singapore in 1930, helping to suppress a rebellion in Burma 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.

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 from RAF Cranwell on 20 May 1927, flown by Flight Lieutenants Roderick Carr and L.E.M Gillmann. It ran out of fuel en route, however, ditching in the Persian Gulf near Bandar Abbas, Iran. Despite this it had covered a distance of 3,420 mi (5,506 km), which was sufficient to set a new world distance record, but was beaten in turn within a few hours by Charles Lindbergh, whose solo Atlantic flight between New York and Paris in the Spirit of St. Louis covered 3,590 mi (5,780 km). The Horsleys remained in service in the day-bombing role until 1934, with 504 Squadron's Horsleys being replaced by Westland Wallaces in March 1934. No 36 Squadron at Singapore retained the Horsely in the Torpedo bomber role until July 1935. The last Horsley, a Merlin powered test bed flew its final flight at RAE Farborough on 7 March 1938.

Source: Hawker Horsley - Wikipedia, the free encyclopedia

 

[gekho]

In the. year 1931 a British Empire Exhibition was held in Buenos Aires, Argentina, at which Westland was represented by a special A.S. Panther-engined Wapiti, G-AAWA, piloted by Mr. H. J. Penrose. This machine embodied the accumulated experience gained with the first 500 Wapitis constructed, and was fitted with a lengthened fuselage and braked undercarriage. After a successful tour in South America the machine was returned to Yeovil, where further refinements were made, including the fitting of a divided axle chassis, improvements to the fuselage lines, and the installation of a Pegasus engine with Townend ring. By this time both the performance and the appearance of the aircraft differed considerably from that of the standard Wapiti and it was given the designation P.V.6, under which it successfully completed Air Ministry acceptance trials as a general-purpose machine. With the placing of a production order the type was given the name of Wallace, but the original machine, again returned to Yeovil, underwent yet another change and was converted for service with the Houston-Mount Everest Expedition.

The very successful realisation of the Expedition's object brought this veteran aircraft once more into Westland hands, this time to be converted back into a standard Wallace and issued to a Squadron. On the early Wallace machines the cockpits were of the open type, with a Scarff gun-ring over the rear cockpit, but the type is now best remembered by reason of a later development. This was the fitting of a transparent cabin over both cockpits, thus making it the first R.A.F. aeroplane to be so equipped. Apart from the greatly increased comfort, this enabled the Wallace to use its rear gun with increased accuracy when operating at maximum speed. The Wallace had a long period of service with the Royal Air Force, and with the various Auxiliary Squadrons, and although succeeded by the Lysander and other general-purpose types.

Source: Westland Wallace - two-seat general-purpose biplane

 

[Gnomey]

Nice stuff!

 

[gekho]

In July 1924, Gloucestershire Aircraft began work on an improved Grebe single-seat fighter to Specification 37/23 and intended to be powered by the 398hp Bristol Jupiter IV nine-cylinder radial engine. Of wooden construction with fabric skinning and retaining the then-standard armament of two synchronised 7.7mm Vickers guns, and to receive the appellation of Gamecock, the prototype was delivered to Martlesham Heath on 20 February 1925. In the following September, an initial order was placed on behalf of the RAF for 30 Gamecock Is powered by the 425hp Jupiter VI. In the event, a further 60 Gamecock Is were built for the RAF (1925-27), one of these (unofficially known as the Gamecock III) at one time flying with a lengthened fuselage, new and enlarged fm-and-rudder assembly and narrow-chord ailerons. A developed version, the Gamecock II, with a steel-tube upper wing centre section, narrow-chord ailerons and a larger rudder, appeared in 1928. This was adopted by Finland, two pattern aircraft and a manufacturing licence being acquired. Fifteen Gamecock IIs were built for the Finnish air arm 1929-30 by the State Aircraft Factory (Valtion Lentokonenetehdas), these having the lengthened fuselage tested earlier in the UK by the so-called Gamecock III and being powered initially by the 420hp Gnome-Rhone Jupiter (IV) 9Ab or 9Ak and later by the 480hp Jupiter (IV) 9Ag. The last Gamecock Is were withdrawn from first-line RAF service mid-1931, Gamecock IIs remaining first-line Finnish equipment until 1935.

Source: Gloster Gamecock - fighter

 

[gekho]

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 Ills with Fairey Reid propellers and other refinements. A small number of the genuine Mk Ills 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 Ills was the 423kW Rolls-Royce Kestrel IIMS, giving a maximum speed of 257km/h as a landplane. Seaplane Ospreys had twin floats, although an interesting but unsuccessful 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.

Source: Hawker Osprey - reconnaissance, spotter aircraft

 

[gekho]

The Flycatcher was designed to meet the requirements of Specification N6/22 for a carrier and floatplane fighter to replace the Gloster Nightjar, powered by either the Armstrong Siddeley Jaguar or the Bristol Jupiter radial engines. Both Fairey and Parnall submitted designs to meet this specification, with Fairey producing the Flycatcher, and Parnall, the Parnall Plover. The first of three prototype Flycatchers made its maiden flight on 28 November 1922, powered by a Jaguar II engine, although later being fitted with a Jupiter IV. Small orders were placed for both the Flycatcher (for nine aircraft) and Plover (for ten aircraft) to allow service evaluation. After trials, the Flycatcher was ordered for full production.

Production of the Flycatcher began at Fairey's Hayes factory in 1923, entering service with No. 402 Flight Fleet Air Arm. The Flycatcher was flown from all the British carriers of its era. Some 192 were produced. A typical deployment was on the aircraft carrier HMS Courageous, where 16 Flycatchers would serve alongside 16 Blackburn Ripons and 16 reconnaissance aircraft. Very popular with pilots, the Flycatchers were easy to fly and very manoeuvrable. It was in them that the Fleet Air Arm developed the combat tactics used in the Second World War. The Flycatcher saw service with the Home, Mediterranean, East Indies and China fleets. During its service on the China station, the Flycatcher was active against Chinese pirates in the waters near Hong Kong.

 

[gekho]

The all-metal Vildebeest was adopted by the RAF as a standard torpedo-carrying and bombing biplane and went into service in Mk.I form in 1933. Powered by a 462kW Bristol Pegasus IM3 engine, it was of unusual shape, with the pilot occupying an open cockpit below the leading edge of the upper wing and the observer aft of the wings in a shallower and lower section of the fuselage. A prone bombing position was provided below the pilot's seat. Armament comprised one fixed Vickers gun firing through the propeller and one Lewis gun on a Scarff ring over the back cockpit. The crutch for the 450mm torpedo or bomb rack was under the fuselage between the two legs of the landing gear. The Mk.I was followed into service by the Mks.II to IV, powered by 484kW Pegasus IIM3 and 603kW Bristol Perseus VIII engines. Total production for the RAF was just over 200, about half of which were still operational at the outbreak of World War II. In addition the Vildebeest was adopted by the Spanish Ministry of Marine as a standard torpedo-carrying seaplane and a batch of about 27 were ordered from the Spanish CASA firm, which had acquired a manufacturing licence. These were powered by 443kW Hispano-Suiza 12Nbr engines. Subsequently the RNZAF also acquired more than 30 Vildebeests.

The Vincent was a three-seat general-purpose version of the Vildebeest, designed essentially for tropical service in the Middle East and therefore carrying comprehensive equipment. Fitted with a 484kW Bristol Pegasus IIM3 engine, it (like the Vildebeest) had sufficient fuel as standard for a 1000km flight while cruising at 195km/h; this range could be increased to 2000km by the use of an auxiliary fuel tank attached in the position normally occupied by the torpedo. A number of Vildebeests were converted into Vincents and, with new production aircraft, the RAF operated just under 200 from 1934. The last were withdrawn in 1941.

 

[yulzari]

An ex RAF target tug pilot, who was using Westland Wallaces, told me they were all fitted up with bomb racks in the Battle of Britain and would have been used to bomb any invading German forces. A bit more effective than the bomber Tiger Moths of Operation Banquet. I gather the Hart series being used as trainers were also issued bomb racks so there would have been a lot more bombers over the beaches than people realise. After all, biplane Hectors, Swordfishes and Albacores dive bombed German forces in the Pas de Calais in May /June 1940.

 

[Airframes]

Good stuff. BTW, in the photo of the Gamecock, the chap on the left is Douglas Bader, before he lost his legs.

 

[johnbr]

Hawker Hector | BAE Systems | International

 

[Wurger]