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55-468: The PWS-12 was a single-engined two-seat training biplane, fit also for aerobatics, designed in 1928 by A. Grzędzielewski and August Bobek-Zdaniewski at the PWS factory. The design shared similar parts, including fuselage and engine, as a high-wing trainer fighter plane PWS-11 , developed at the same time. The main difference was the addition of a lower wing. It was powered by a nose-mounted Skoda-built version of

110-573: A rigid fixture . These formers are then joined with lightweight longitudinal elements called stringers . These are in turn covered with a skin of sheet aluminum, attached by riveting or by bonding with special adhesives. The fixture is then disassembled and removed from the completed fuselage shell, which is then fitted out with wiring, controls, and interior equipment such as seats and luggage bins. Most modern large aircraft are built using this technique, but use several large sections constructed in this fashion which are then joined with fasteners to form

165-522: A decision had been made to re-equip RAF Bomber Command exclusively with a new generation of four-engine bombers. Just as the earlier, and now obsolescent Wellington was being relegated to secondary roles, the Warwick was used for general reconnaissance (long range anti-submarine patrols), air-sea rescue, operational crew training and as a transport, where its obsolescence wasn't as much of a problem. By January 1943, 57 Warwick Mk.Is had been completed, when it

220-485: A design is intended to be "self jigging", not requiring a complete fixture for alignment. Early aircraft were constructed of wood frames covered in fabric. As monoplanes became popular, metal frames improved the strength, which eventually led to all-metal-structure aircraft, with metal covering for all its exterior surfaces - this was first pioneered in the second half of 1915 . Some modern aircraft are constructed with composite materials for major control surfaces, wings, or

275-596: A few minutes due to a failed carburettor linkage. The smaller Wellington had flown three years earlier and had already been in production for 18 months by then. When fully equipped, the calculated all-up weight of the first prototype was 42,182 lb (19,133 kg), almost double the weight given by Vickers in their initial tender for the design. Flight tests with the prototype revealed it to be slow, underpowered and unable to maintain altitude on one engine. The second prototype flew on 5 April 1940 with Centaurus engines and incorporated improvements to its design, such as

330-574: A fire which began in the starboard engine. Only 16 aircraft were delivered as bombers, as by this time more capable four-engined heavy bombers such as the Short Stirling and Handley Page Halifax were in service. Those Warwicks that were delivered in the bomber configuration saw little use as such, instead being used to investigate various kinds of equipment and technical matters, including navigational equipment, engine performance, role suitability, and air-dropped lifeboats . It soon became clear that

385-457: A freight floor, long-range fuel tanks and exhaust stack flame dampers for night flights. The Warwick used Barnes Wallis ' geodetic airframe construction pioneered in the Wellesley . In this system, a network of intersecting structural members made from duralumin were covered by wired-on fabric. The load was distributed across the structure, providing great redundancy in the event of damage, at

440-598: A handful of transport Warwicks. In October 1932, the British industrial conglomerate Vickers-Armstrongs tendered for the Air Ministry Specification B.9/32 , which called for the development of a twin-engined medium bomber. During late 1934, when the company was already developing their Type 271 to meet Specification B.9/32, Vickers received a draft requirement for a larger bomber. The draft specification developed into Air Ministry Specification B.1/35, which sought

495-465: A large warplane which uses this process). The logical evolution of this is the creation of fuselages using molded plywood, in which several sheets are laid with the grain in differing directions to give the monocoque type below. In this method, the exterior surface of the fuselage is also the primary structure. A typical early form of this (see the Lockheed Vega ) was built using molded plywood , where

550-471: A larger counterpart to the Vickers Wellington bomber. The two aircraft share similar construction and design principles but development of the Warwick was delayed by a lack of suitable engines. Its first flight was on 13 August 1939 but delays to its intended powerplant and by the time adequate engines were available, it was obsolete. The Warwick entered production during 1942 and squadron service with

605-447: A portion of the external load (i.e. from wings and empennage, and from discrete masses such as the engine) is taken by the surface covering. In addition, all the load from internal pressurization is carried (as skin tension ) by the external skin. The proportioning of loads between the components is a design choice dictated largely by the dimensions, strength, and elasticity of the components available for construction and whether or not

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660-576: A re-designed elevator , to improve handling. There was a definite improvement in performance and it was claimed that the second prototype was faster than a Hawker Hurricane , at certain altitudes. While the Centaurus-powered prototype was more promising, development was at an early stage. In October 1939, it was proposed that it be redesigned as a four-engined aircraft, with either Rolls-Royce Merlin XX or Bristol Hercules HE7SM engines but after some study,

715-528: A scratch pane near the passenger. Acrylic is susceptible to crazing  : a network of fine cracks appears but can be polished to restore optical transparency , removal and polishing typically undergo every 2–3 years for uncoated windows. " Flying wing " aircraft, such as the Northrop YB-49 Flying Wing and the Northrop B-2 Spirit bomber have no separate fuselage; instead what would be

770-409: A similar modification of the series being in production. It caused some financial problems for the factory, since a production of PWS-12s had already started. As a result, the factory delivered in 1932 a series of 20 PWS-14, marked officially as PWS-12 (military numbers 57.1 - 57.20). A further development of PWS-14 was PWS-16 , and then PWS-26 . The PWS-14s, officially marked as PWS-12s, were used by

825-612: A triangular extension ahead of the fin. The Double Wasps fitted to early models were unreliable while later versions fitted with the Centaurus engine had better performance but the handling problems were never completely solved. Warwick BV243 was converted into a transport for trials. An additional 13 Mk.Is were converted on the production line as C Mk.I transports for BOAC. BOAC's Warwicks were used briefly on its Middle East services before being transferred back to RAF Transport Command in 1944. One hundred similar aircraft were built for

880-492: A twin-engined heavy strategic bomber . It was intended to make use of more powerful engines, of 1,000 hp (750 kW), that were being developed, to enable the bomber to be faster and carry a heavier bomb load than the earlier B.3/34. Among the requirements of Specification B.1/35 was a speed of no less than 195 mph (314 km/h) while flying at 15,000 ft (4,600 m), a range of 1,500 mi (2,400 km) while carrying 2,000 lb (910 kg) of bombs, and

935-445: Is composed of 4–6 panels, 35 kg (77 lb) each on an Airbus A320 . In its lifetime, an average aircraft goes through three or four windshields , and the market is shared evenly between OEM and higher margins aftermarket . Cabin windows, made from much lighter than glass stretched acrylic glass , consists of multiple panes: an outer one built to support four times the maximum cabin pressure, an inner one for redundancy and

990-465: Is prevalent in the series production of many modern sailplanes . The use of molded composites for fuselage structures is being extended to large passenger aircraft such as the Boeing 787 Dreamliner (using pressure-molding on female molds). This is the preferred method of constructing an all- aluminum fuselage. First, a series of formers in the shape of the fuselage cross sections are held in position on

1045-427: Is required for aircraft stability and maneuverability. This type of structure is still in use in many lightweight aircraft using welded steel tube trusses. A box truss fuselage structure can also be built out of wood—often covered with plywood. Simple box structures may be rounded by the addition of supported lightweight stringers, allowing the fabric covering to form a more aerodynamic shape, or one more pleasing to

1100-567: The English Channel and the North Sea . Only 235 of the production order for 525 Warwick Mk.V were completed, most of which went directly into storage in 1944. In early 1945, some examples of this stored variant was issued to 179 Squadron, stationed at RAF St Eval . Four Warwick GR Mk.Vs crashed on test flights from Brooklands during the first half of 1945. The first of these was PN773 which suffered an engine failure on take-off on 2 January and

1155-524: The French fuselé "spindle-shaped") is an aircraft 's main body section. It holds crew , passengers, or cargo . In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft the single engine is mounted on a pylon attached to the fuselage, which in turn is used as a floating hull . The fuselage also serves to position the control and stabilization surfaces in specific relationships to lifting surfaces , which

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1210-519: The Rolls-Royce Vulture liquid-cooled X engine was named as the alternative powerplant of the Vickers 284 and it was adopted in late 1938. The Vulture, which had also been intended for the rival Avro Manchester , was subsequently determined to be unlikely to be available in sufficient numbers for the Warwick, as well as being unreliable, and on 2 July 1937, an order for a second prototype was placed

1265-745: The Royal Air Force (RAF). Barely a dozen aircraft were built as bombers. The type was used by RAF Transport Command as a transport, and by RAF Coastal Command as an air-sea rescue and maritime reconnaissance aircraft. The Warwick was also operated by the Polish Air Forces in exile in Great Britain and the South African Air Force . A civil operator, the British Overseas Airways Corporation (BOAC), also operated

1320-474: The Rutan VariEze ). An example of a larger molded plywood aircraft is the de Havilland Mosquito fighter/light bomber of World War II . No plywood-skin fuselage is truly monocoque , since stiffening elements are incorporated into the structure to carry concentrated loads that would otherwise buckle the thin skin. The use of molded fiberglass using negative ("female") molds (which give a nearly finished product)

1375-613: The Vickers 456 Warwick C.Mk.I was made for British Overseas Airways Corporation (BOAC), a civil operator. Operational requirements were for the carriage of mail, freight and passengers between Bathurst in South Africa and Cairo in Egypt, complementing BOAC's flying boat operations between England and Bathurst. The order was met by converting existing B.Mk.Is, by removing military equipment, fairing over gun turret openings, adding cabin windows,

1430-800: The Wright J-5 Whirlwind radial engine. Two prototypes and an airframe for static tests were ordered by the Aviation Department of the War Ministry in February 1928 (along with the PWS-11 prototypes). The first prototype was flown by Franciszek Rutkowski in November 1929. It was later improved - among others, a Townend ring replaced NACA cowling , and it was fitted with N-shaped struts between wings instead of perpendicular struts. The second improved prototype

1485-509: The geodetic airframe structure, the latter having been used on several previous designs by British aircraft designer Barnes Wallis . In February 1939, development beyond the pair of prototypes was cancelled because of difficulties with the Vulture engine but this was reversed the following January. In late June 1939, following the completion of a high-level review and an update of programme data, work resumed. While Vickers chose to continue with

1540-436: The 1,700 lb (770 kg) Mk.IA airborne lifeboat and used for air-sea rescue. The lifeboat, designed by yachtsman Uffa Fox , laden with supplies and powered by two 4 hp (3.0 kW) motors, was aimed with a bomb-sight to be dropped under parachute near ditched air crew from an altitude of about 700 ft (210 m). Warwicks were credited with rescuing crews from a wide variety of contemporary aircraft both in

1595-648: The Air Ministry as insurance against the failure of the Vulture. The second prototype ( L9704 ) was designed for the Napier Sabre engine but development was slow, and production capacity was urgently required for the Hawker Typhoon fighter. L9704 was instead fitted with the Bristol Centaurus radial engine . Other aspects of the design proved troublesome, such as the gun turrets and official doubts over

1650-701: The Polish Air Force from 1933 in the Officer Training Centre in Dęblin and a Flying School in Grudziądz . Most were next replaced by the PWS-16 and PWS-26 , some remained in use until World War II in 1939. The second prototype PWS-12bis (factory no. 358) was modified in 1931 to a role of an aerobatics aircraft. Among others, fuselage sides were made flat and a rudder shape was changed. It received markings SP-AKE and

1705-779: The RAF as Warwick C Mk.IIIs, and entered service with 525 Squadron in June 1944, with three more squadrons operating the Warwick III. They were mainly used in the Mediterranean theatre, as the vulnerability of the fabric skinning to high temperature and humidity stopped plans to operate the Warwick in the Far East, and remained in use until retired in 1946. The remainder of the first batch of 250 Warwicks were used by RAF Coastal Command for anti-submarine reconnaissance. From 1943, Warwicks were fitted with

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1760-402: The Vickers 285. As a consequence of the relaxation of the restrictions imposed by the 1932 Geneva Disarmament Conference , the weight of the Vickers 284 and 285 expanded gradually, until the 285 approached the original specified weight for Specification B.1/35. During 1936, Specification B.1/34 was modified to require the aircraft to carry more fuel and a heavier bombload. During January 1937,

1815-561: The Warwick, with its spacious fuselage and long range, would be well suited to utility roles. In January 1943, the Air Staff decided that the Warwick would serve as the predominant aircraft for transport and air-sea rescue. Early testing showed the Warwick to be under-powered and with severe handling problems, especially when flown on one engine. Stability and control trials commenced with the third production Warwick, which yielded acceptable handling during single engine operations when fitted with

1870-481: The advantage of being made almost entirely of wood. A similar construction using aluminum alloy was used in the Vickers Warwick with less material than would be required for other structural types. The geodesic structure is also redundant and so can survive localized damage without catastrophic failure. A fabric covering over the structure completed the aerodynamic shell (see the Vickers Wellington for an example of

1925-616: The complete fuselage. As the accuracy of the final product is determined largely by the costly fixture, this form is suitable for series production, where many identical aircraft are to be produced. Early examples of this type include the Douglas Aircraft DC-2 and DC-3 civil aircraft and the Boeing B-17 Flying Fortress . Most metal light aircraft are constructed using this process. Both monocoque and semi-monocoque are referred to as "stressed skin" structures as all or

1980-520: The engines were to be furnished with variable-pitch propellers . It was designed in parallel with the smaller Wellington , both aircraft having been derived from the Vickers Type 271 design, developed for Specification B.9/32. By the end of July 1935, the Air Ministry was considering eight designs. These included Vicker's proposal, the Type 284, powered by a pair of Bristol Hercules engines, which exceeded

2035-631: The entire fuselage such as the Boeing 787. On the 787, it makes possible higher pressurization levels and larger windows for passenger comfort as well as lower weight to reduce operating costs. The Boeing 787 weighs 1,500 lb (680 kg) less than if it were an all-aluminum assembly. Cockpit windshields on the Airbus A320 must withstand bird strikes up to 350 kn (650 km/h) and are made of chemically strengthened glass . They are usually composed of three layers or plies, of glass or plastic :

2090-466: The expense of complexity of construction. The first production Warwick B Mk.I was delivered to the RAF for testing at the Aeroplane and Armament Experimental Establishment , Boscombe Down on 3 July 1942. This first aircraft was lost when fabric panels on the wings came loose on 28 January 1942. The second production Warwick took its place in flying trials but on 18 February 1943, it too was destroyed, by

2145-402: The eye. Geodesic structural elements were used by Barnes Wallis for British Vickers between the wars and into World War II to form the whole of the fuselage, including its aerodynamic shape. In this type of construction multiple flat strip stringers are wound about the formers in opposite spiral directions, forming a basket-like appearance. This proved to be light, strong, and rigid and had

2200-485: The fuselage is a thickened portion of the wing structure. Conversely, there have been a small number of aircraft designs which have no separate wing, but use the fuselage to generate lift. Examples include National Aeronautics and Space Administration 's experimental lifting body designs and the Vought XF5U-1 Flying Flapjack . A blended wing body can be considered a mixture of the above. It carries

2255-582: The idea was discarded as it reduced range and payload. Another proposal used the American Pratt & Whitney Double Wasp radial engine. Performance projections showed similar performance to the Hercules III-powered Wellington but with a significantly greater payload and the engines were also available due to the cancellation of contracts previously placed by the French. The second prototype

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2310-634: The inner two are 8 mm (0.3 in.) thick each and are structural, while the outer ply, about 3 mm thick, is a barrier against foreign object damage and abrasion , with often a hydrophobic coating. It must prevent fogging inside the cabin and de-ice from −50 °C (−58 °F). This was previously done with thin wires similar to a rear car window but is now accomplished with a transparent, nanometers-thick coating of indium tin oxide sitting between plies, electrically conductive and thus transmitting heat. Curved glass improves aerodynamics but sight criteria also needs larger panes. A cockpit windshield

2365-420: The layers of plywood are formed over a "plug" or within a mold . A later form of this structure uses fiberglass cloth impregnated with polyester or epoxy resin as the skin, instead of plywood. A simple form of this used in some amateur-built aircraft uses rigid expanded foam plastic as the core, with a fiberglass covering, eliminating the necessity of fabricating molds, but requiring more effort in finishing (see

2420-483: The project, official doubts, over slow progress caused by work on the Wellington and the lack of suitable engines, led to a growing official expectation that the design would be surpassed by later aircraft. On 13 August 1939, the first prototype (serial K8178 ), powered by Vulture engines, made its first flight from Brooklands , with test pilot Joseph "Mutt" Summers at the controls but the test flight only lasted for

2475-455: The proposed aircraft was officially named in accordance with the Air Ministry's practice of naming bombers after British towns and cities and with Vickers using 'W' as the initial letter to indicate the designs of Barnes Wallis. The large initial production contract came despite the need to resolve troubles with the Centaurus engine. The Double Wasp engine, with a three-bladed 15 ft (4.6 m) diameter Hamilton Standard propeller, became

2530-633: The specifications. Vickers received an order for a prototype on 7 October 1935, while the Air Ministry also ordered prototypes from Armstrong Whitworth (the AW.39, a development of the Armstrong Whitworth Whitley ) and Handley Page (the HP.55). These alternative designs were cancelled before being built, as Handley Page and Armstrong Whitworth switched to work on newer specifications released for medium (P.13/36) and heavy (B.12/36) bombers. As Specification B.1/35

2585-463: The useful load in a fuselage producing lift. A modern example is Boeing X-48 . One of the earliest aircraft using this design approach is Burnelli CBY-3 , which fuselage was airfoil shaped to produce lift. Vickers Warwick This is an accepted version of this page The Vickers Warwick was a British twin-engined bomber aircraft developed and operated during the Second World War that

2640-527: The usual powerplant. Due to the time it took for the Double Wasps to reach Vickers in Britain from Pratt & Whitney in the U.S., delays were unavoidable. During 1941, the second prototype flight tested a modified tail to improved handling. The prototype was fitted with production engines and propellers however this revealed problems with engine ignition, which was resolved with a revised booster coil. The Warwick

2695-514: Was converted to use the R-2800-S14A4-G engines and was flown in July 1941. The Double Wasp installation was inferior to the Centaurus but was ordered regardless. On 3 January 1941, an initial production order was placed for 250 Warwicks, consisting of 150 Double Wasp-powered Mk.I aircraft and 100 Centaurus-powered Mk.IIs, with deliveries to commence in November that year. It was at this point that

2750-481: Was decided that they would be used primarily as transports and air-sea rescue aircraft. During mid-1943, a Warwick Mk.I was converted to become the Warwick Mk.II prototype with the principal difference being the installation of Centaurus IV engines. 219 Warwick Mk.I aircraft were completed, with the last 95 of these fitted with 2,000 hp (1,500 kW) R-2800-47 engines. In 1942, an order for 14 Warwick transports,

2805-682: Was flown mainly by Lt. J. Orłowski. In March 1931 it was used in a trip to Estonia, and in April 1933 - to Romania, Bulgaria, Yugoslavia, Austria and Czechoslovakia. Then, both prototypes were used for several years as utility aircraft in Aviation Technical Research Institute (ITBL). They were later stored in Dęblin. Data from Glass, A. (1977) General characteristics Performance Related development Fuselage The fuselage ( / ˈ f juː z əl ɑː ʒ / ; from

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2860-409: Was flown on 18 November 1930, and designated PWS-12bis. Testing was successful and a production order for 20 aircraft was placed by the Polish Air Force. In a meantime, the factory developed improved model PWS-14, featuring a change from wooden to a steel-tube fuselage, strengthened wings and other improvements, like a door in first cockpit's side. The War Ministry ordered a production of one PWS-14 and

2915-461: Was primarily used in other roles. In line with the naming convention followed by other RAF heavy bombers of the era, it was named after a British city or town, in this case Warwick . The Warwick was the largest British twin-engined aircraft to see use during the Second World War. The Warwick was designed and manufactured by Vickers-Armstrongs during the late 1930s. It was intended to serve as

2970-525: Was subject to considerable study to keep it relevant to the rapidly changing circumstances of the conflict, and it was out of this process that a work towards standardised production was made. Due to persistent engine shortages and a change in policy, only 16 of the planned 150 Warwick bombers were completed. Even as the first bomber was nearing completion at Weybridge , the type was failing to meet Air Staff requirements for bomber aircraft. Bombers were being expected to carry much greater bombloads further, and

3025-458: Was to be a heavier complement to Specification B.9/32, it was initially thought that there would be no need for a mock-up. On 14 March 1936, in light of major design changes being submitted, production of a complete mock-up was authorised. Around the same time, it was decided to allocate the Vickers 284 type number to the project, while the redesigned B.9/32 (which would become the Wellington) became

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