The de Havilland Mosquito was a British combat aircraft that excelled in a number of roles during the Second World War. It served with the RAF and many other air forces both in the Second World War and postwar. The Mosquito was known affectionately as the "Mossie" to its crews.

The Mosquito was a twin-engine aircraft, powered by a pair of Rolls-Royce Merlins with the pilot and navigator sitting side by side. Unorthodox in design, it used a plywood structure of spruce and balsa in a time when wooden construction was considered outmoded. In the conceptual design stage, de Havilland designers found that adding any defensive armament would significantly reduce the aircraft's maximum speed. Realising that the loss in performance was not worth the benefit, the initial bomber version was designed without any guns. The Mosquito was a very versatile aircraft; originally conceived as a fast day bomber, the various roles of the Mosquito included: tactical bomber, pathfinder, day or night fighter, fighter-bomber, intruder, maritime strike and photo reconnaissance aircraft.

Construction:

The genius of the aircraft's construction lay in the innovative and somewhat unorthodox use of seemingly commonplace materials and techniques. The bulk of the Mosquito was made of plywood. Stronger and lighter than most grades of plywood, this special plywood was produced by a combination of 3/8" sheets of Ecuadorean balsawood sandwiched between sheets of Canadian birch plywood. Like a deck of cards, sheets of wood alternated with sheets of a special casein-based (later formaldehyde) wood glue.

The fuselage was formed in concrete moulds. Left and right sides of the fuselage were fitted with bulkheads and structural members separately while the glue cured. Reinforcing was achieved with hundreds of small brass wood screws. This arrangement greatly simplified the installation of hydraulic lines and other fittings, as the two halves of the fuselage were open for easy access by workers. The halves were then glued and bolted together, and covered with doped Madapolam fabric.

The wings were also made of wood. To increase strength, the wings were made as one single assembly, onto which the fuselage, once both halves had been mated, was lowered and attached.

Metal was used sparingly in the construction of structural elements. It was mostly used in engine mounts and fairings, control surfaces, and, of course, brass screws.

Fighter-bomber versions:

Operational experience in its varied roles quickly led to the development of a versatile fighter-bomber version; the Mosquito FB Mk.VI, which first saw service in early 1943. The Mosquito FB Mk.VI had a strengthened wing for external loads and along with its standard fighter armament could carry two 250 lb bombs in the rear of the bomb bay and two 250 lb bombs under the wings, or eight wing-mounted rockets. Later up-engined versions could carry 500 lb bombs. The FB Mk.VI became the most numerous version of the Mosquito, (2,292 built) equipping the day bomber 2 Group, the intruder squadrons of Fighter Command and 2nd TAF, and the strike wings of Coastal Command, who used the variant as a potent anti-shipping aircraft armed with eight "60 lb" rockets.