De Havilland Mosquito

were later used in the Mosquito. By the early to mid-1930s, de Havilland had built a reputation for innovative high-speed aircraft with the DH.88 Comet racer. Later, the DH.91 Albatross airliner pioneered the composite wood construction used for the Mosquito. The 22-passenger Albatross could cruise at at , faster than the Handley Page H.P.42 and other biplanes it was replacing. The wooden monocoque construction not only saved weight and compensated for the low power of the de Havilland Gipsy Twelve engines used by this aircraft, but also simplified production and reduced construction time. Air Ministry bomber requirements and concepts On 8 September 1936, the British Air Ministry issued Specification P.13/36, which called for a twin-engined medium bomber capable of carrying a bomb load of for with a maximum speed of at ; a maximum bomb load of carried over shorter ranges was also required. Aviation firms entered heavy designs with new high-powered engines and multiple defensive turrets, leading to the production of the Avro Manchester and Handley Page Halifax. In May 1937, as a comparison to P.13/36, George Volkert, the chief designer of Handley Page, put forward the concept of a fast, unarmed bomber. In 20 pages, Volkert planned an aerodynamically clean, medium bomber to carry of bombs at a cruising speed of . Support existed in the RAF and Air Ministry; Captain R. N. Liptrot, Research Director Aircraft 3, appraised Volkert's design, calculating that its top speed would exceed that of the new Supermarine Spitfire, but counter-arguments held that although such a design had merit, it would not necessarily be faster than enemy fighters for long. The ministry was also considering using non-strategic materials for aircraft production, which, in 1938, had led to specification B.9/38 and the Armstrong Whitworth Albemarle medium bomber, largely constructed from spruce and plywood attached to a steel-tube frame. The idea of a small, fast bomber gained support at a much earlier stage than is sometimes acknowledged, though the Air Ministry likely envisaged it using light alloy components. Inception of the de Havilland fast bomber design to create a fast bomber. Based on his experience with the Albatross, Geoffrey de Havilland believed that a bomber with a good aerodynamic design and smooth, minimal skin area, would exceed the P.13/36 specification. Furthermore, adapting the Albatross principles could save time. In April 1938, performance estimates were produced for a twin Rolls-Royce Merlin-powered DH.91, with the Bristol Hercules (radial engine) and Napier Sabre (H-engine) as alternatives. At a meeting in early October 1938 with Geoffrey de Havilland and Charles Walker (de Havilland's chief engineer), the Air Ministry showed little interest, and instead asked de Havilland to build wings for other bombers as a subcontractor. By September 1939, de Havilland had produced preliminary estimates for single- and twin-engined variations of light-bomber designs using different engines, speculating on the effects of defensive armament on their designs. One design, completed on 6 September, was for an aircraft powered by a single Napier Sabre, with a wingspan of and capable of carrying a bomb load . On 20 September, in another letter to Wilfrid Freeman, de Havilland wrote "…we believe that we could produce a twin-engine bomber which would have a performance so outstanding that little defensive equipment would be needed." For more versatility, Bishop made provision for four 20 mm cannon in the forward half of the bomb bay, under the cockpit, firing via blast tubes and troughs under the fuselage. The DH.98 was too radical for the ministry, which wanted a heavily armed, multirole aircraft, combining medium bomber, reconnaissance, and general-purpose roles, that was also capable of carrying torpedoes. With the outbreak of war, the ministry became more receptive, but was still sceptical about an unarmed bomber. They thought the Germans would produce fighters that were faster than had been expected. and suggested the incorporation of two forward- and two rear-firing machine guns for defence. The ministry also opposed a two-man bomber, wanting at least a third crewman to reduce the work of the others on long flights. On 12 December, the Vice-Chief of the Air Staff, Director General of Research and Development, and the Air Officer Commanding-in-Chief (AOC-in-C) of RAF Bomber Command met to finalise the design and decide how to fit it into the RAF's aims. The AOC-in-C would not accept an unarmed bomber, but insisted on its suitability for reconnaissance missions with F8 or F24 cameras. After company representatives, the ministry, and the RAF's operational commands examined a full-scale mock-up at Hatfield on 29 December 1939, the project received backing. This was confirmed on 1 January 1940, when Freeman chaired a meeting with Geoffrey de Havilland, John Buchanan (Deputy of Aircraft Production), and John Connolly (Buchanan's chief of staff). De Havilland claimed the DH.98 was the "fastest bomber in the world… it must be useful". Freeman supported it for RAF service, ordering a single prototype for an unarmed bomber to specification B.1/40/dh, which called for a light bomber/reconnaissance aircraft powered by two Rolls-Royce RM3SM (an early designation for the Merlin 21) with ducted radiators, capable of carrying a bomb load. In May 1940, specification F.21/40 was issued, calling for a long-range fighter armed with four 20 mm cannon and four .303 machine guns in the nose, after which de Havilland was authorised to build a prototype of a fighter version of the DH.98. After debate, it was decided that this prototype, given the military serial number W4052, was to carry aircraft interception (AI) Mk IV radar equipment as both a day fighter and night fighter. By June 1940, the DH.98 had been named "Mosquito". Work was cancelled again after the evacuation of the British Army from France, when Lord Beaverbrook, as Minister of Aircraft Production, concentrating production on aircraft types for the defence of the UK decided no production capacity remained for aircraft like the DH.98, which was not expected to be in service until early 1942. Beaverbrook told Air Vice-Marshal Freeman that work on the project should stop, but he did not issue a specific instruction, and Freeman ignored the request. In June 1940, however, Lord Beaverbrook and the Air Staff ordered that production should concentrate on five existing types, namely the Supermarine Spitfire, Hawker Hurricane fighter, Vickers Wellington, Armstrong-Whitworth Whitley, and Bristol Blenheim bombers. The Mosquito was only reinstated as a priority in July 1940, after de Havilland's general manager, L.C.L. Murray, promised Lord Beaverbrook 50 Mosquitoes by December 1941. This was only after Beaverbrook was satisfied that Mosquito production would not hinder de Havilland's primary work of producing Tiger Moth and Airspeed Oxford trainers, repairing Hurricanes, and manufacturing Merlin engines under licence. During the Battle of Britain, interruptions to production due to air raid warnings caused nearly a third of de Havilland's factory time to be lost. Nevertheless, work on the prototype went ahead quickly at Salisbury Hall since E-0234 was completed by November 1940. In the aftermath of the Battle of Britain, the original order was changed to 20 bomber variants and 30 fighters. Whether the fighter version should have dual or single controls, or should carry a turret, was still uncertain, so three prototypes were built: W4052, W4053, and W4073. The second and third, both turret armed, were later disarmed, to become the prototypes for the T.III trainer. This caused some delays, since half-built wing components had to be strengthened for the required higher combat loading. The nose sections also had to be changed from a design with a clear perspex bomb-aimer's position, to one with a solid nose housing four .303 machine guns and their ammunition. The aircraft reached , with the only problem being the undercarriage doors, which were operated by bungee cords attached to the main undercarriage legs, and remained open by some at that speed. On 5 December 1940, the prototype, with the military serial number W4050, experienced tail buffeting at speeds between . The pilot noticed this most in the control column, with handling becoming more difficult. During testing on 10 December, wool tufts were attached to suspect areas to investigate the direction of airflow. The conclusion was that the airflow separating from the rear section of the inner engine nacelles was disturbed, leading to a localised stall and the disturbed airflow was striking the tailplane, causing buffeting. To smooth the air flow and deflect it from forcefully striking the tailplane, nonretractable slots fitted to the inner engine nacelles and to the leading edge of the tailplane were tested. These slots and wing-root fairings fitted to the forward fuselage and leading edge of the radiator intakes stopped some of the vibration experienced, but did not cure the tailplane buffeting. In February 1941, buffeting was eliminated by incorporating triangular fillets on the trailing edge of the wings and lengthening the nacelles, the trailing edge of which curved up to fair into the fillet some behind the wing's trailing edge; this meant the flaps had to be divided into inboard and outboard sections. With the buffeting problems largely resolved, John Cunningham flew W4050 on 9 February 1941. He was greatly impressed by the "lightness of the controls and generally pleasant handling characteristics". Cunningham concluded that when the type was fitted with aircraft interception equipment (AI), it might replace the Bristol Beaufighter night fighter. On 24 February, as W4050 taxied across the rough airfield, the tailwheel jammed leading to the fuselage fracturing. Repairs were made by early March, using part of the fuselage of the photo-reconnaissance prototype W4051. In spite of this setback, the Initial Handling Report 767 issued by the AAEE stated, "The aeroplane is pleasant to fly… aileron control light and effective..." The maximum speed reached was at , with an estimated maximum ceiling of and a maximum rate of climb of at . In late October 1941, it returned to the factory to be fitted with Merlin 61s, the first production Merlins fitted with a two-speed, two-stage supercharger. The first flight with the new engines was on 20 June 1942. W4050 recorded a maximum speed of at (fitted with straight-through air intakes with snow guards, engines in full supercharger gear) and at without snow guards. In October 1942, in connection with development work on the NF Mk.XV, W4050 was fitted with extended wingtips, increasing the span to , first flying in this configuration on 8 December. Fitted with high-altitude-rated, two-stage, two-speed Merlin 77s, it reached in December 1943. near St Albans W4051, which was designed from the outset to be the prototype for the photo-reconnaissance versions of the Mosquito, was slated to make its first flight in early 1941. However, the fuselage fracture in W4050 meant that ''W4051's fuselage was used as a replacement; W4051 was then rebuilt using a production standard fuselage and first flew on 10 June 1941. This prototype continued to use the short engine nacelles, single-piece trailing-edge flaps, and the "No. 1" tailplane used by W4050'', but had production-standard wings and became the only Mosquito prototype to fly operationally. Construction of the fighter prototype, W4052, was also carried out at Salisbury Hall. It was powered by Merlin 21s, and had an altered canopy structure with a flat, bullet-proof windscreen; the solid nose had mounted four .303 British Browning machine guns and their ammunition boxes, accessible by a large, sideways hinged panel. Four 20-mm Hispano Mk.II cannon were housed in a compartment under the cockpit floor with the breeches projecting into the bomb bay and the automatic bomb bay doors were replaced by manually operated bay doors, which incorporated cartridge ejector chutes. As a day and night fighter, prototype W4052 was equipped with AI Mk IV equipment, complete with an "arrowhead" transmission aerial mounted between the central Brownings and receiving aerials through the outer wing tips, and it was painted in black RDM2a "Special Night" finish. It was also the first prototype constructed with the extended engine nacelles. W4052 was later tested with other modifications, including bomb racks, drop tanks, barrage balloon cable cutters in the leading edge of the wings, Hamilton airscrews and braking propellers, and drooping aileron systems that enabled steep approaches and a larger rudder tab. It continued to serve as a test machine until it was scrapped on 28 January 1946. On 20 April 1941, W4050 was demonstrated to Lord Beaverbrook, the Minister of Aircraft Production. The Mosquito made a series of flights, including one rolling climb on one engine. Also present were US General Henry H. Arnold and his aide Major Elwood Quesada, who wrote "I… recall the first time I saw the Mosquito as being impressed by its performance, which we were aware of. We were impressed by the appearance of the airplane that looks fast usually is fast, and the Mosquito was, by the standards of the time, an extremely well-streamlined airplane, and it was highly regarded, highly respected." The trials set up future production plans between Britain, Australia, and Canada. Six days later, Arnold returned to America with a full set of manufacturer's drawings. As a result of his report, five companies (Beech, Curtiss-Wright, Fairchild, Fleetwings, and Hughes) were asked to evaluate the de Havilland data. The report by Beech Aircraft summed up the general view: "It appears as though this airplane has sacrificed serviceability, structural strength, ease of construction and flying characteristics in an attempt to use construction material which is not suitable for the manufacture of efficient airplanes." The Americans did not pursue the proposal for licensed production, the consensus arguing that the Lockheed P-38 Lightning could fulfill the same duties. However, Arnold urged the United States Army Air Forces (USAAF) to evaluate the design even if they would not adopt it. On 12 December 1941, after the attack on Pearl Harbor, the USAAF requested one airframe for this purpose. ==Design and manufacture==

Overview While timber construction for aircraft was considered outmoded by some, de Havilland claimed that their successes with techniques used for the DH 91 Albatross could lead to a fast, light bomber using monocoque-sandwich shell construction. Arguments in favour of this included speed of prototyping, rapid development, minimisation of jig-building time, and employment of a separate category of workforce; many production facilities and skilled carpenters that previously manufactured furniture were repurposed to create components for the Mosquito, leveraging an existing workforce whose expertise was generally not being utilised during the war effort. The ply-balsa-ply monocoque fuselage and one-piece wings with doped fabric covering would give excellent aerodynamic performance and low weight, combined with strength and stiffness. At the same time, the design team had to fight conservative Air Ministry views on defensive armament. Guns and gun turrets, favoured by the ministry, would impair the aircraft's aerodynamic properties and reduce speed and manoeuvrability, in the opinion of the designers. While submitting these arguments, Geoffrey de Havilland funded his private venture until a very late stage. The project was a success beyond all expectations. As a multi-role warplane, the Mosquito came in multiple versions: photo-reconnaissance (PR), bomber (B), fighter (F), night fighter (NF), fighter-bomber (FB), torpedo bomber (TR) with fold-up wings to fit more on a carrier, and trainer (T), each with varying modifications and weapon loadouts. Typical gun armament was four .303 caliber Browning machine guns and four 20 mm Hispano autocannons. Bomb load could be up to 4,000 lb (1,800 kg), allowing the Mosquito to carry a single "Cookie" blockbuster bomb, or a number of smaller ones. The most-produced variant, designated the FB Mk. VI (Fighter-bomber Mark 6), was powered by two Merlin Mk.23 or Mk.25 engines driving three-bladed de Havilland hydromatic propellers. The typical fixed armament for an FB Mk. VI was four Browning .303 machine guns and four 20-mm Hispano cannons, while the offensive load consisted of up to of bombs, or eight RP-3 unguided rockets. Performance The design was noted for light and effective control surfaces that provided good manoeuvrability, but required that the rudder not be used aggressively at high speeds. Poor aileron control at low speeds when landing and taking off was also a problem for inexperienced crews. For flying at low speeds, the flaps had to be set at 15°, speed reduced to , and rpm set to 2,650. The speed could be reduced to an acceptable for low-speed flying. Early on in the Mosquito's operational life, the intake shrouds that were to cool the exhausts on production aircraft overheated. Flame dampers prevented exhaust glow on night operations, but they had an effect on performance. Multiple ejector and open-ended exhaust stubs helped solve the problem and were used in the PR.VIII, B.IX, and B.XVI variants. This increased speed performance in the B.IX alone by . In many generally smaller but vital areas, such as around apertures and attachment zones, stronger timbers, including aircraft-quality spruce, replaced the balsa core. The main areas of the sandwich skin were only thick. Together with various forms of wood reinforcement, often of laminated construction, the sandwich skin gave great stiffness and torsional resistance. The separate fuselage halves speeded construction, permitting access by personnel working in parallel with others, as the work progressed. Work on the separate half-fuselages included installation of control mechanisms and cabling. Screwed inserts into the inner skins that would be under stress in service were reinforced using round shear plates made from a fabric-Bakelite composite. Transverse bulkheads were also compositely built-up with several species of timber, plywood, and balsa. Seven vertically halved bulkheads were installed within each moulded fuselage shell before the main "boxing up" operation. Bulkhead number seven was especially strongly built, since it carried the fitments and transmitted the aerodynamic loadings for the tailplane and rudder. The fuselage had a large ventral section cut-out, strongly reinforced, that allowed the fuselage to be lowered onto the wing centre-section at a later stage of assembly. To provide for the edge joints for the fuselage halves, zones near the outer edges of the shells had their balsa sandwich cores replaced by much stronger inner laminations of birch plywood. For the bonding together of the two halves ("boxing up"), a longitudinal cut was machined into these edges. The profile of this cut was a form of V-groove. Part of the edge bonding process also included adding further longitudinal plywood lap strips on the outside of the shells. For finishing, a covering of doped madapollam (a fine, plain-woven cotton) fabric was stretched tightly over the shell and several coats of red, followed by silver dope, were added, followed by the final camouflage paint. Wing The all-wood wing pairs formed a single structural unit throughout the wingspan, with no central longitudinal joint. Instead, the spars ran from wingtip to wingtip. There was a single continuous main spar and another continuous rear spar. Because of the combination of dihedral with the forward sweep of the trailing edges of the wings, this rear spar was one of the most complex units to laminate and to finish machining after the bonding and curing. It had to produce the correct 3D tilt in each of two planes. Also, it was designed and made to taper from the wing roots towards the wingtips. Both principal spars were of ply box construction, using in general 0.25-in plywood webs with laminated spruce flanges, plus a number of additional reinforcements and special details. Spruce and plywood ribs were connected with gusset joints. Some heavy-duty ribs contained pieces of ash and walnut, as well as the special five ply that included veneers laid up at 45°. The upper skin construction was in two layers of 0.25-in five-ply birch, separated by Douglas fir stringers running in the span-wise direction. The wings were covered with madapollam fabric and doped in a similar manner to the fuselage. The wing was installed into the roots by means of four large attachment points. The engine radiators were fitted in the inner wing, just outboard of the fuselage on either side. These gave less drag. The radiators themselves were split into three sections: an oil cooler section outboard, the middle section forming the coolant radiator and the inboard section serving the cabin heater. The wing contained metal-framed and -skinned ailerons, but the flaps were made of wood and were hydraulically controlled. The nacelles were mostly wood, although for strength, the engine mounts were all metal, as were the undercarriage parts. Engine mounts of welded steel tube were added, along with simple landing gear oleos filled with rubber blocks. Wood was used to carry only in-plane loads, with metal fittings used for all triaxially loaded components such as landing gear, engine mounts, control-surface mounting brackets, and the wing-to-fuselage junction. The outer leading wing edge had to be brought further forward to accommodate this design. markings, PRU Blue finish at the National Museum of the United States Air Force. In November 1944, several crashes occurred in the Far East. At first, these were thought to be a result of wing-structure failures. The casein glue, it was said, cracked when exposed to extreme heat and/or monsoon conditions. This caused the upper surfaces to lift from the main spar. An investigating team led by Major Hereward de Havilland travelled to India and produced a report in early December 1944 stating, "the accidents were not caused by the deterioration of the glue, but by shrinkage of the airframe during the wet monsoon season". However, a later inquiry by Cabot & Myers firmly attributed the accidents to faulty manufacture and this was confirmed by a further investigation team by the Ministry of Aircraft Production at Defford, which found faults in six Mosquito marks (all built at de Havilland's Hatfield and Leavesden plants). The defects were similar, and none of the aircraft had been exposed to monsoon conditions or termite attack. The investigators concluded that construction defects occurred at the two plants. They found that the "…standard of glueing… left much to be desired." Records at the time showed that accidents caused by "loss of control" were three times more frequent on Mosquitoes than on any other type of aircraft. The Air Ministry forestalled any loss of confidence in the Mosquito by holding to Major de Havilland's initial investigation in India that the accidents were caused "largely by climate". To solve the problem of seepage into the interior, a strip of plywood was set along the span of the wing to seal the entire length of the skin joint. These were complemented by two inner wing fuel tanks, each containing , located between the wing root and engine nacelle. In the central fuselage were twin fuel tanks mounted between bulkhead number two and three aft of the cockpit. In the FB.VI, these tanks contained each, Both the inner wing, and fuselage tanks are listed as the "main tanks" and the total internal fuel load of was initially deemed appropriate for the type. The FB.VI had a wingspan of , a length (over guns) of . It had a maximum speed of at . Maximum take-off weight was and the range of the aircraft was with a service ceiling of . To reduce fuel vaporisation at the high altitudes of photographic reconnaissance variants, the central and inner wing tanks were pressurised. The pressure venting cock located behind the pilot's seat controlled the pressure valve. As the altitude increased, the valve increased the volume applied by a pump. This system was extended to include field modifications of the fuel tank system. The engine oil tanks were in the engine nacelles. Each nacelle contained a oil tank, including a air space. The oil tanks themselves had no separate coolant controlling systems. The coolant header tank was in the forward nacelle, behind the propeller. The remaining coolant systems were controlled by the coolant radiators shutters in the forward inner wing compartment, between the nacelle and the fuselage and behind the main engine cooling radiators, which were fitted in the leading edge. Electric-pneumatic operated radiator shutters directed and controlled airflow through the ducts and into the coolant valves, to predetermined temperatures. Electrical power came from a 24 volt DC generator on the starboard (No. 2) engine and an alternator on the port engine, which also supplied AC power for radios. The main landing gear, housed in the nacelles behind the engines, were raised and lowered hydraulically. The main landing gear shock absorbers were de Havilland manufactured and used a system of rubber in compression, rather than hydraulic oleos, with twin pneumatic brakes for each wheel. The Dunlop-Marstrand anti-shimmy tailwheel was also retractable. ==Operational history==

, Copenhagen, Denmark, in March 1945. A Mosquito pulling away from its bombing run is visible on the extreme left, centre. The de Havilland Mosquito operated in many roles, performing medium bomber, reconnaissance, tactical strike, anti-submarine warfare, shipping attacks and night fighter duties, until the end of the war. On 13 July 1941, the first production PR Mosquito W4051 (a production fuselage combined with some prototype flying surfaces – see Prototypes and test flights) was sent to No. 1 Photographic Reconnaissance Unit (PRU), at RAF Benson. The secret reconnaissance flights of this aircraft were the first operational missions of the Mosquito. In 1944, the journal Flight gave 19 September 1941 as date of the first PR mission, at an altitude "of some 20,000 ft". On 15 November 1941, 105 Squadron, RAF, took delivery at RAF Swanton Morley, Norfolk, of the first operational Mosquito Mk. B.IV bomber, serial no. W4064. Throughout 1942, 105 Squadron, based next at RAF Horsham St. Faith, then from 29 September, RAF Marham, undertook daylight low-level and shallow dive attacks. Apart from the Oslo and Berlin raids, the strikes were mainly on industrial and infrastructure targets in occupied Netherlands and Norway, France and northern and western Germany. The crews faced deadly flak and fighters, particularly Focke-Wulf Fw 190s, which they called snappers. Germany still controlled continental airspace and the Fw 190s were often already airborne and at an advantageous altitude. Collisions within the formations also caused casualties. It was the Mosquito's excellent handling capabilities, rather than pure speed, that facilitated successful evasions. The Mosquito was first announced publicly on 26 September 1942 after the Oslo Mosquito raid of 25 September. It was featured in The Times on 28 September and the next day the newspaper published two captioned photographs illustrating the bomb strikes and damage. On 6 December 1942, Mosquitoes from Nos. 105 and 139 Squadrons made up part of the bomber force used in Operation Oyster, the large No. 2 Group raid against the Philips works at Eindhoven. From mid-1942 to mid-1943, Mosquito bombers flew high-speed, medium and low-altitude daylight missions against factories, railways and other pinpoint targets in Germany and German-occupied Europe. From June 1943, Mosquito bombers were formed into the Light Night Striking Force to guide RAF Bomber Command heavy bomber raids and as "nuisance" bombers, dropping Blockbuster bombs – "cookies" – in high-altitude, high-speed raids that German night fighters were almost powerless to intercept. As a night fighter from mid-1942, the Mosquito intercepted Luftwaffe raids on Britain, notably those of Operation Steinbock in 1944. Starting in July 1942, Mosquito night-fighter units raided Luftwaffe airfields. As part of 100 Group, it was flown as a night fighter and as an intruder supporting Bomber Command heavy bombers that reduced losses during 1944 and 1945. The Mosquito fighter-bomber served as a strike aircraft in the Second Tactical Air Force (2TAF) from its inception on 1 June 1943. The main objective was to prepare for the invasion of occupied Europe a year later. In Operation Overlord three Mosquito FB Mk. VI wings flew close air support for the Allied armies in co-operation with other RAF units equipped with the North American B-25 Mitchell medium bomber. In the months between the foundation of 2TAF and its duties from D day onwards, vital training was interspersed with attacks on V-1 flying bomb launch sites. In another example of the daylight precision raids carried out by the Mosquitoes of Nos. 105 and 139 Squadrons, on 30 January 1943, the 10th anniversary of the Nazis' seizure of power, a morning Mosquito attack knocked out the main Berlin broadcasting station while Luftwaffe Chief Reichsmarschall Hermann Göring was speaking, putting his speech off the air. A second sortie in the afternoon inconvenienced another speech, by Propaganda Minister Joseph Goebbels. Lecturing a group of German aircraft manufacturers, Göring said: During this daylight-raiding phase, Nos. 105 and 139 Squadrons flew 139 combat operations and aircrew losses were high. Even the losses incurred in the squadrons' dangerous Blenheim era were exceeded in percentage terms. The Roll of Honour shows 51 aircrew deaths from the end of May 1942 to April 1943. In the corresponding period, crews gained three Mentions in Despatches, two DFMs and three DFCs. The low-level daylight attacks finished on 27 May 1943 with strikes on the Schott glass and Zeiss instrument works, both in Jena. Subsequently, when low-level precision attacks required Mosquitoes, they were allotted to squadrons operating the FB.IV version. Examples include the Aarhus air raid and Operation Jericho. Since the beginning of the year, the German fighter force had become seriously overstretched. In April 1943, in response to "political humiliation" caused by the Mosquito, Göring ordered the formation of special Luftwaffe units (Jagdgeschwader 25, commanded by Oberstleutnant Herbert Ihlefeld and Jagdgeschwader 50, under Major Hermann Graf) to combat the Mosquito attacks, though these units, which were "little more than glorified squadrons", were unsuccessful against the elusive RAF aircraft. Post-war German histories also indicate that there was a belief within the Luftwaffe that Mosquito aircraft "gave only a weak radar signal." The first Mosquito Squadron to be equipped with the Oboe bomb aiming system was No. 109, based at RAF Wyton, after working as an experimental unit at RAF Boscombe Down. They used Oboe operationally for the first time on 31 December 1942 and 1 January 1943, target marking for a force of heavy bombers attacking Düsseldorf. On 1 June, the two pioneering Squadrons joined No. 109 Squadron in the re-formed No. 8 Group RAF (Bomber Command). Initially they were engaged in moderately high altitude (about ) night bombing, with 67 trips during that summer, mainly to Berlin. Soon after, Nos. 105 and 139 Squadron bombers were widely used by the RAF Pathfinder Force, marking targets for the main night-time strategic bombing force. Particularly after the introduction of H2S (radar) in some Mosquitoes, raids carrying large bombs succeeded to the extent that they provided a significant additional form of attack to the large formations of "heavies." Latterly in the war, there were a significant number of all-Mosquito raids on big German cities involving up to 100 or more aircraft. On the night of 20/21 February 1945, for example, Mosquitoes of No. 8 Group mounted the first of 36 consecutive night raids on Berlin. From 1943, Mosquitoes with RAF Coastal Command attacked Kriegsmarine U-boats and intercepted transport ship concentrations. After Operation Overlord, the U-boat threat in the Western Approaches decreased fairly quickly, but correspondingly the Norwegian and Danish waters posed greater dangers. Hence the RAF Coastal Command Mosquitoes were moved to Scotland to counter this threat. The Strike Wing at Banff stood up in September 1944 and comprised Mosquito aircraft of No's 143, 144, 235 and 248 Squadrons Royal Air Force and No.333 Squadron Royal Norwegian Air Force. Despite an initially high loss rate, the Mosquito bomber variants ended the war with the lowest losses of any aircraft in RAF Bomber Command service. Strike Wing attacking a convoy evacuating German troops in the Kattegat on 5 April 1945. A flak ship and a trawler were sunk. The Mosquito also proved a very capable night fighter. Some of the most successful RAF pilots flew these variants. For example, Wing Commander Branse Burbridge claimed 21 kills. Mosquitoes of No. 100 Group RAF acted as night intruders operating at high level in support of the Bomber Command "heavies", to counter the enemy tactic of merging into the bomber stream, which, towards the end of 1943, was causing serious Allied losses. These RCM (radio countermeasures) aircraft were fitted with a device called "Serrate" to allow them to track down German night fighters from their Lichtenstein B/C (low-UHF-band) and Lichtenstein SN-2 (lower end of the VHF FM broadcast band) radar emissions, as well as a device named "Perfectos" that tracked German IFF signals. These methods were responsible for the destruction of 257 German aircraft from December 1943 to April 1945. Mosquito fighters from all units accounted for 487 German aircraft during the war, the vast majority of which were night fighters. Night fighter Mosquitos were often tasked with attacking German planes landing at airfields. In 1943, the Germans became acquainted with Moskitoschreck, "Mosquito terror," the constant fear of an unexpected Mosquito attack during a nighttime landing. In 1947–49, up to 180 Canadian surplus Mosquitoes flew many operations for the Nationalist Chinese under Chiang Kai-shek in the civil war against Communist forces. Pilots from three squadrons of Mosquitoes claimed to have sunk or damaged 500 ships during one invasion attempt. As the Communists assumed control, the remaining aircraft were evacuated to Formosa, where they flew missions against shipping. ==Variants==

Until the end of 1942 the RAF always used Roman numerals (I, II...) for mark numbers; 1943–48 was a transition period during which new aircraft entering service were given Arabic numerals (1, 2...) for mark numbers, but older aircraft retained their Roman numerals. From 1948 onwards, Arabic numerals were used exclusively. Prototypes Three prototypes were built, each with a different configuration. The first to fly was W4050 on 25 November 1940, followed by the fighter W4052 on 15 May 1941 and the photo-reconnaissance prototype W4051 on 10 June 1941. W4051 later flew operationally with 1 Photographic Reconnaissance Unit (1 PRU). Photo-reconnaissance s onto a PR Mk.XVI of No. 140 Squadron RAF at B58/Melsbroek, Belgium, circa 1944–1945 A total of ten Mosquito PR Mk.Is were built, four of them "long range" versions equipped with a overload fuel tank in the fuselage. All of the PR Mk.Is, and the B Mk.IV Series 1s, had the original short engine nacelles and short span (19 ft 5.5 in) tailplanes. Their engine cowlings incorporated the original pattern of integrated exhaust manifolds, which, after relatively brief flight time, had a troublesome habit of burning and blistering the cowling panels. The first operational sortie by a Mosquito was made by a PR Mk.I, W4055, on 17 September 1941; during this sortie the unarmed Mosquito PR.I evaded three Messerschmitt Bf 109s at . Powered by two Merlin 21s, the PR Mk.I had a maximum speed of , a cruise speed of , a ceiling of , a range of , and a climb rate of per minute. The first operational flight by a PR Mk.IV was made by DK284 in April 1942. The Mosquito PR Mk.VIII, built as a stopgap pending the introduction of the refined PR Mk.IX, was the next photo-reconnaissance version. The five VIIIs were converted from B Mk.IVs and became the first operational Mosquito version to be powered by two-stage, two-speed supercharged engines, using Rolls-Royce Merlin 61 engines in place of Merlin 21/22s. The first PR Mk.VIII, DK324 first flew on 20 October 1942. The PR Mk.VIII had a maximum speed of , an economical cruise speed of at 20,000 ft, and at 30,000 ft, a ceiling of , a range of , and a climb rate of 2,500 ft per minute (760 m). The Mosquito PR Mk.IX, 90 of which were built, was the first Mosquito variant with two-stage, two-speed engines to be produced in quantity; the first of these, LR405, first flew in April 1943. A total of 435 of the PR Mk.XVI were built. The Mosquito PR Mk.34 and PR Mk.34A was a very long-range unarmed high altitude photo-reconnaissance version. The fuel tank and cockpit protection armour were removed. Additional fuel was carried in a bulged bomb bay: 1,192 gallons—the equivalent of . A further two 200-gallon (910-litre) drop tanks under the outer wings gave a range of cruising at . Powered by two Merlin 114s first used in the PR.32. The port Merlin 114 drove a Marshal cabin supercharger. A total of 181 were built, including 50 built by Percival Aircraft Company at Luton. All PR.34s were installed with four split F52 vertical cameras, two forward, two aft of the fuselage tank and one F24 oblique camera. Sometimes a K-17 camera was used for air surveys. In August 1945, the PR.34A was the final photo-reconnaissance variant with one Merlin 113A and 114A each delivering . Colonel Roy M. Stanley II, USAF (RET) wrote: "I consider the Mosquito the best photo-reconnaissance aircraft of the war". After the end of World War II Spartan Air Services used ten ex-RAF Mosquitoes, mostly B.35s plus one of only six PR.35s built, for high-altitude photographic survey work in Canada. Bombers , becoming GB-O. On 21 June 1941 the Air Ministry ordered that the last ten Mosquitoes, ordered as photo-reconnaissance aircraft, should be converted to bombers. These ten aircraft were part of the original 1 March 1940 production order and became the B Mk.IV Series 1. W4052 was to be the prototype and flew for the first time on 8 September 1941. The bomber prototype led to the B Mk.IV, of which 273 were built: apart from the 10 Series 1s, all of the rest were built as Series 2s with extended nacelles, revised exhaust manifolds, with integrated flame dampers, and larger tailplanes. Series 2 bombers also differed from the Series 1 in having an increased payload of four bombs, instead of the four bombs of Series 1. This was made possible by cropping, or shortening the tail of the bomb so that these four heavier weapons could be carried (or a 2,000 lb (920 kg) total load). In April 1943 it was decided to convert a B Mk.IV to carry a Blockbuster bomb (nicknamed "cookie"). The conversion, including modified bomb bay suspension arrangements, bulged bomb bay doors and fairings, was relatively straightforward and 54 B.IVs were modified and distributed to squadrons of the Light Night Striking Force. 27 B Mk.IVs were later converted for special operations with the Highball anti-shipping weapon, and were used by 618 Squadron, formed in April 1943 specifically to use this weapon. A B Mk.IV, DK290 was initially used as a trials aircraft for the bomb, followed by DZ471,530 and 533. The B Mk.IV had a maximum speed of , a cruising speed of , ceiling of , a range of , and a climb rate of 2,500 ft per minute (12.7 m/s). The Merlin 31 powered B Mk.VII was built by de Havilland Canada and first flown on 24 September 1942. It only saw service in Canada, 25 were built. Six were handed over to the United States Army Air Forces. B Mk.IX (54 built) was powered by the Merlin 72,73, 76 or 77. The two-stage Merlin variant was based on the PR.IX. The prototype DK 324 was converted from a PR.VIII and first flew on 24 March 1943. In October 1943 it was decided that all B Mk.IVs and all B Mk.IXs then in service would be converted to carry the "Cookie", and all B Mk.IXs built after that date were designed to allow them to be converted to carry the weapon. The B Mk.IX had a maximum speed of , an economical cruise speed of at 20,000 ft, and at 30,000 ft, The B Mk.XVI was powered by the same variations as the B.IX. All B Mk.XVIs were capable of being converted to carry the "Cookie". A total of 174 B.35s were delivered up to the end of 1945. A further 100 were delivered from 1946 for a grand total of 274, 65 of which were built by Airspeed Ltd. Fighters Developed during 1940, the first prototype of the Mosquito F Mk.II was completed on 15 May 1941. These Mosquitoes were fitted with four Hispano cannon in the fuselage belly and four .303 (7.7 mm) Browning machine guns mounted in the nose. On production Mk.IIs the machine guns and ammunition tanks were accessed via two centrally hinged, sideways opening doors in the upper nose section. To arm and service the cannon the bomb bay doors were replaced by manually operated bay doors: the F and NF Mk.IIs could not carry bombs. In the summer of 1942, Britain experienced day-time incursions of the high-altitude reconnaissance bomber, the Junkers Ju 86P. Although the Ju 86P only carried a light bomb load, it overflew sensitive areas, including Bristol, Bedfordshire and Hertfordshire. Bombs were dropped on Luton and elsewhere, and the aircraft responsible was seen from the main de Havilland offices and factory at Hatfield. An attempt to intercept it with a Spitfire from RAF Manston was unsuccessful. As a result of the potential threat, a decision was quickly taken to develop a high-altitude Mosquito interceptor, using the MP469 prototype. MP469 entered the experimental shop on 7 September and made its initial flight on 14 September, piloted by John de Havilland. The bomber nose was altered using a normal fighter nose, armed with four standard .303 (7.7 mm) Browning machine guns. The low pressure cabin retained a bomber canopy structure and a two-piece windscreen. The control wheel was replaced with a fighter control stick. The wingspan was increased to . The airframe was lightened by removing armour plating, some fuel tanks and other fitments. Smaller-diameter main wheels were fitted after the first few flights. At a loaded weight of this HA Mk.XV was lighter than a standard Mk.II. For this first conversion, the engines were a pair of Merlin 61s. On 15 September, John de Havilland reached an altitude of in this version. The aircraft was delivered to a High Altitude Flight which had been formed at RAF Northolt. However, the high-level German daylight intruders were no longer to be seen. It was subsequently revealed that only five Ju 86P aircraft had been built and they had only flown 12 sorties. Nevertheless, the general need for high altitude interceptors was recognised – but now the emphasis was to be upon night fighters. The A&AEE tested the climb and speed of night fighter conversion of MP469 in January 1943 for the Ministry of Aircraft Production. Wingspan had been increased to , the Brownings had been moved to a fairing below the fuselage. According to Birtles, an AI radar was mounted in the nose and the Merlins were upgraded to Mk76 type, although Boscombe Down reported Merlin 61s. In addition to MP469, four more B Mk.IVs were converted into NF MK XVs. The Fighter Interception Unit at RAF Ford carried out service trials, March 1943, and then these five aircraft went to 85 Squadron, Hunsdon, where they were flown from April until August of that year. The greatest height reached in service was . Apart from the F Mk.XV, all Mosquito fighters and fighter bombers featured a modified canopy structure incorporating a flat, single-piece armoured windscreen, and the crew entry/exit door was moved from the bottom of the forward fuselage to the right side of the nose, just forward of the wing leading edge. Night fighters , January 1944. Just visible is part of the aerial array for the A.I. Mk.IV near the wingtip. At the end of 1940, the Air Staff's preferred turret-equipped night fighter design to Operational Requirement O.R. 95 was the Gloster F.18/40 (derived from their F.9/37). However, although in agreement as to the quality of the Gloster company's design, the Ministry of Aircraft Production was concerned that Gloster would not be able to work on the F.18/40 and also the jet fighter design, considered the greater priority. Consequently, in mid-1941 the Air Staff and MAP agreed that the Gloster aircraft would be dropped and the Mosquito, when fitted with a turret would be considered for the night fighter requirement. The first production night fighter Mosquitoes – minus turrets – were designated NF Mk.II. A total of 466 were built with the first entering service with No. 157 Squadron in January 1942, replacing the Douglas Havoc. These aircraft were similar to the F Mk.II, but were fitted with the AI Mk.IV metric wavelength radar. The herring-bone transmitting antenna was mounted on the nose and the dipole receiving antennae were carried under the outer wings. A number of NF IIs had their radar equipment removed and additional fuel tanks installed in the bay behind the cannon for use as night intruders. These aircraft, designated NF II (Special) were first used by 23 Squadron in operations over Europe in 1942. 23 Squadron was then deployed to Malta on 20 December 1942, and operated against targets in Italy. Ninety-seven NF Mk.IIs were upgraded with 3.3 GHz frequency, low-SHF-band AI Mk.VIII radar and these were designated NF Mk.XII. The NF Mk.XIII, of which 270 were built, was the production equivalent of the Mk.XII conversions. These "centimetric" radar sets were mounted in a solid "thimble" (Mk.XII / XIII) or universal "bull nose" (Mk.XVII / XIX) radome, which required the machine guns to be dispensed with. , with the "bull nose", caught in the beam of a Chance light on the main runway at Foggia, Italy, before taking off on a night intruder sortie. Four F Mk.XVs were converted to the NF Mk.XV. These were fitted with AI Mk.VIII in a "thimble" radome, and the .303 Brownings were moved into a gun pack fitted under the forward fuselage. NF Mk.XVII was the designation for 99 NF Mk.II conversions, with single-stage Merlin 21, 22, or 23 engines, but British AI.X (US SCR-720) radar. The NF Mk.XIX was an improved version of the NF XIII. It could be fitted with American or British AI radars; 220 were built. The NF Mk.30 was the final wartime variant and was a high-altitude version, powered by two Rolls-Royce Merlin 76s. The NF Mk.30 had a maximum speed of at . It also carried early electronic countermeasures equipment. 526 were built. After the war, two more night fighter versions were developed: The NF Mk.36 was similar to the Mosquito NF Mk.30, but fitted with the American-built AI.Mk.X radar. Powered by two Rolls-Royce Merlin 113/114 piston engines; 266 built. Max level speeds (TAS) with flame dampers fitted were at sea level, at , and at . According to the Pilot's Notes and Air Ministry 'Special Flying Instruction TF/487', which posted limits on the Mosquito's maximum speeds, the NF Mk.38 had a VNE of 370 knots (425 mph), without under-wing stores, and within the altitude range of sea level to . However, from 10,000 to the maximum speed was 348 knots (400 mph). As the height increased other recorded speeds were; 15,000 to 320 knots (368 mph); 20,000 to , 295 knots (339 mph); 25,000 to , 260 knots (299 mph); 30,000 to , 235 knots (270 mph). With two added 100-gallon fuel tanks this performance fell; between sea level and 15,000 feet 330 knots (379 mph); between 15,000 and 320 knots (368 mph); 20,000 to , 295 knots (339 mph); 25,000 to , 260 knots (299 mph); 30,000 to , 235 knots (270 mph). Little difference was noted above . Strike ("fighter-bomber") variants The FB Mk. VI, which first flew on 1 June 1942, was powered by two, single-stage two-speed, Merlin 21s or Merlin 25s, and introduced a re-stressed and reinforced "basic" wing structure capable of carrying single bombs on racks housed in streamlined fairings under each wing, or up to eight RP-3 25lb or 60 lb rockets. In addition fuel lines were added to the wings to enable single or drop tanks to be carried under each wing. The usual fixed armament was four 20 mm Hispano Mk.II cannon and four .303 (7.7 mm) Browning machine guns, while two bombs could be carried in the bomb bay. Unlike the F Mk.II, the ventral bay doors were split into two pairs, with the forward pair being used to access the cannon, while the rear pair acted as bomb bay doors. The maximum fuel load was distributed between internal fuel tanks, plus two overload tanks, each of capacity, which could be fitted in the bomb bay, and two drop tanks. 2,298 FB Mk. VIs were built, nearly one third of Mosquito production. , June 1944, shows full invasion stripes and is well weathered through operational use. Another fighter-bomber variant was the Mosquito FB Mk. XVIII (known as the Tsetse) of which one was converted from a FB Mk. VI to serve as prototype and 17 were purpose-built. The Mk.XVIII was armed with a Molins "6-pounder Class M" cannon: this was a modified QF 6-pounder (57 mm) anti-tank gun fitted with an auto-loader to allow both semi- or fully automatic fire. 25 rounds were carried, with the entire installation weighing . Two or four .303 (7.7 mm) Browning machine guns were retained in the nose and were used to "sight" the main weapon onto the target. The prototype HJ732 was converted from a FB.VI and was first flown on 8 June 1943. On 10 June, was abandoned in the face of intense air attack from No. 248 Squadron, and was later sunk by a Liberator of No. 206 Squadron. On 5 April 1945 Mosquitoes with Molins attacked five German surface ships in the Kattegat and again demonstrated their value by setting them all on fire and sinking them. A German Sperrbrecher ("minefield breaker") was lost with all hands, with some 200 bodies being recovered by Swedish vessels. and followed on 19 April and 2 May 1945, also sunk by rockets. . Note the 57 mm Molins gun and streamlined blister used to accommodate the automatic loading mechanism. Despite the preference for rockets, a further development of the large gun idea was carried out using the even larger, 96 mm calibre QF 32-pounder, a gun based on the QF 3.7-inch AA gun designed for tank use, the airborne version using a novel form of muzzle brake. Developed to prove the feasibility of using such a large weapon in the Mosquito, this installation was not completed until after the war, when it was flown and fired in a single aircraft without problems, then scrapped. Designs based on the Mk.VI were the FB Mk. 26, built in Canada, and the FB Mk.40, built in Australia, powered by Packard Merlins. The FB.26 improved from the FB.21 using single stage Packard Merlin 225s. Some 300 were built and another 37 converted to T.29 standard. (wartime + 2 afterwards) Mosquitoes were built by De Havilland Canada at Downsview Airfield in Downsview Ontario (now Downsview Park in Toronto Ontario). • Mosquito B Mk.VII : Canadian version based on the Mosquito B Mk.V bomber aircraft. Powered by two Packard Merlin 31 piston engines; 25 built. • Mosquito B Mk.XX : Canadian version of the Mosquito B Mk.IV bomber aircraft; 145 built, of which 40 were converted into F-8 photo-reconnaissance aircraft for the USAAF. • Mosquito FB Mk.21 : Canadian version of the Mosquito FB Mk. VI fighter-bomber aircraft. Powered by two Rolls-Royce Merlin 31 piston engines, three built. Mosquito CF-HMS arrives Calgary, February, 1964 • Mosquito T Mk.22 : Canadian version of the Mosquito T Mk.III training aircraft. • Mosquito B Mk.23 : Unused designation for a bomber variant. • Mosquito FB Mk.24 : Canadian fighter-bomber version. Powered by two Rolls-Royce Merlin 301 piston engines; two built. • Mosquito B Mk.25 : Improved version of the Mosquito B Mk.XX Bomber aircraft. Powered by two Packard Merlin 225 piston engines; 400 built. • Mosquito FB Mk.26 : Improved version of the Mosquito FB Mk.21 fighter-bomber aircraft. Powered by two Packard Merlin 225 piston engines; 338 built. • Mosquito T Mk.27 : Canadian-built training aircraft. • Mosquito T Mk.29 : A number of FB Mk.26 fighters were converted into T Mk.29 trainers. Australian-built • Mosquito FB Mk.40 : Two-seat fighter-bomber version for the RAAF. Powered by two Rolls-Royce Merlin 31 piston engines. A total of 178 built in Australia. • Mosquito PR Mk.40 : This designation was given to six FB Mk.40s, which were converted into photo-reconnaissance aircraft. • Mosquito FB Mk.41 : Two-seat fighter-bomber version for the RAAF. A total of 11 were built in Australia. • Mosquito PR Mk.41 : Two-seat photo-survey version for the RAAF. A total of 17 were built in Australia. • Mosquito FB Mk.42 : Two-seat fighter-bomber version. Powered by two Rolls-Royce Merlin 69 piston engines. One FB Mk.40 aircraft was converted into a Mosquito FB Mk.42. • Mosquito T Mk.43 : Two-seat training version for the RAAF. A total of 11 FB Mk.40s were converted into Mosquito T Mk.43s. Highball A number of Mosquito IVs were modified by Vickers-Armstrongs to carry Highball "bouncing bombs" and were allocated Vickers Type numbers: • Type 463 – Prototype Highball conversion of Mosquito IV DZ741. • Type 465 – Conversion of 33 Mosquito IVs to carry Highball. ==Production==

being prepared for Operation Oyster, December 1942. This aircraft crashed near Shipham while returning from Cologne on 27 January 1943 About 5,000 of the total of 7,781 Mosquitoes built had major structural components fabricated from wood in High Wycombe, Buckinghamshire, England. Fuselages, wings and tailplanes were made at furniture companies such as Ronson, E. Gomme, Parker Knoll, Parslow Furniture, Austinsuite and Styles & Mealing. Wing spars were made by J. B. Heath and Dancer & Hearne. Many of the other parts, including flaps, flap shrouds, fins, leading edge assemblies and bomb doors were also produced in the Buckinghamshire town. Dancer & Hearne processed much of the wood from start to finish, receiving timber and transforming it into finished wing spars at their factory in Penn Street on the outskirts of High Wycombe. Initially much of the specialised yellow birch wood veneer and finished plywood used for the prototypes and early production aircraft was shipped from firms in Wisconsin, US. Prominent in this role were Roddis Plywood and Veneer Manufacturing in Marshfield. In conjunction with the USDA Forest Products Laboratory, Hamilton Roddis had developed new plywood adhesives and hot pressing technology. Later on, paper birch was logged in large quantities from the interior of British Columbia along the Fraser and Quesnel Rivers and processed in Quesnel and New Westminster by the Pacific Veneer Company. According to the Quesnel archives, BC paper birch supplied ½ of the wartime British Empire birch used for Mosquitoes and other aircraft. As the supply of Ecuadorean balsa was threatened by the U-boats in the Atlantic Ocean, the Ministry of Aircraft Production approved a research effort to supplant the balsa with calcium alginate foam, made from local brown algae. By 1944 the foam was ready, but the U-boat threat had been reduced, the larger B-25 bombers were in sufficient supply to handle most of the bombing raids, and the foam was not used in Mosquito production. Canada In July 1941, it was decided that DH Canada would build Mosquitoes at Downsview, Ontario. This was to continue even if Germany invaded Great Britain. Packard Merlin engines produced under licence were bench-tested by August and the first two aircraft were built in September. Production was to increase to fifty per month by early 1942. Initially, the Canadian production was for bomber variants; later, fighters, fighter-bombers and training aircraft were also made. DH Chief Production Engineer, Harry Povey, was sent first, then W. D. Hunter followed on an extended stay, to liaise with materials and parts suppliers. As was the case with initial UK production, Tego-bonded plywood and birch veneer was obtained from firms in Wisconsin, principally Roddis Plywood and Veneer Manufacturing, Marshfield. Enemy action delayed the shipping of jigs and moulds and it was decided to build these locally. During 1942, production improved to over 80 machines per month, as sub-contractors and suppliers became established. A mechanised production line based in part on car building methods started in 1944. As the war progressed, Canadian Mosquitoes may have utilized paper birch supplied by the Pacific Veneer Company of New Westminster using birch logs from the Cariboo, although records only say this birch was shipped to England for production there. When flight testing could no longer keep up, this was moved to the Central Aircraft Company airfield, London, Ontario, where the approved Mosquitoes left for commissioning and subsequent ferry transfer to Europe. Ferrying Mosquitoes and many other types of WWII aircraft from Canada to Europe was dangerous, resulting in losses of lives and machines, but in the exigencies of war it was regarded as the best option for twin-engine and multi-engine aircraft. Considerable efforts were made by de Havilland Canada to resolve problems with engine and oil systems and an additional five hours of flight testing were introduced before the ferry flight, but the actual cause of some of the losses was unknown. Nevertheless, by the end of the war, nearly 500 Mosquito bombers and fighter-bombers had been ferried successfully by the Canadian operation. After DH Canada had been established for the Mosquito, further manufacturing was set up at DH Australia, in Sydney. One of the DH staff who travelled there was the distinguished test pilot, Pat Fillingham. These production lines added totals of 1,133 aircraft of varying types from Canada plus 212 aircraft from Australia. Exports In total, both during the war and after, de Havilland exported 46 FB.VIs and 29 PR. XVIs to Australia; two FB.VI and 18 NF.30s to Belgium; approximately 250 FB.26, T.29 and T.27s from Canada to China. A significant number never went into service due to deterioration on the voyage and to crashes during Chinese pilot training; however, five were captured by the People's Liberation Army during the Chinese Civil War; 19 FB.VIs to Czechoslovakia in 1948; 6 FB.VIs to Dominica; a few B.IVs, 57 FB.VIs, 29 PR.XVIs and 23 NF.30s to France. Some T.IIIs were exported to Israel along with 60 FB.VIs, and at least five PR.XVIs and 14 naval versions. Four T.IIIs, 76 FB.VIs, one FB.40 and four T.43s were exported to New Zealand. Three T.IIIs were exported to Norway, and 18 FB.VIs, which were later converted to night fighter standard. South Africa received two F.II and 14 PR.XVI/XIs and Sweden received 60 NF.XIXs. Turkey received 96 FB.VIs and several T.IIIs, and Yugoslavia had 60 NF.38s, 80 FB.VIs and three T.IIIs delivered. At least one de Havilland Mosquito was delivered to the Soviet Union, marked 'DK 296'. Sites Total Mosquito production was 7,781, of which 6,710 were built during the war. ==Civilian accidents and incidents==

A number of Mosquitoes were lost in civilian airline service, mostly with British Overseas Airways Corporation during the Second World War. • On 17 August 1943, G-AGGF crashed near Glenshee, Perthshire. • On 25 October 1943, G-AGGG crashed near RAF Leuchars. At the time, this was the last airworthy Mosquito, a T.III. == Operators ==

• • • • • • • • • • • • • • • • • • • • • • • • == Surviving aircraft ==

There are approximately 30 non-flying Mosquitoes around the world with five airworthy examples: three in the United States; one in Canada; and one in New Zealand. The largest collection of Mosquitoes is at the de Havilland Aircraft Museum in the United Kingdom, which owns three aircraft, including the first prototype, W4050, the only initial prototype of a Second World War British aircraft design still in existence in the 21st century. ==Specifications (B Mk.XVI)==

==Notable appearances in media==