One of the most successful bombers of World War II, the Mosquito, was also known as The Timber Terror, because of its outside-the-box design:
Despite shortages in the metal supply, the Royal Air Force (RAF) made plans to broaden their air fleet to include a new variety of bomber which was somewhat smaller and faster. In 1936 the RAF commissioned several companies to submit designs for such a plane, and a civilian outfit called De Havilland responded with a highly unorthodox concept: a bomber constructed almost entirely out of plywood. Initially the British Air Ministry scoffed at the idea, and suggested that the airplane company instead use its resources to construct wings for existing bomber designs. But the people at De Havilland were convinced that their unconventional idea had some merit.The aircraft designers originally conceived of a wooden airframe armed with several gun turrets and a six-man crew, all propelled by a pair of Rolls-Royce Merlin engines. A series of calculations soon indicated that such a plane wouldn’t be particularly fast given its heavy weight, so the engineers discussed adding two additional engines to bring it up to the speed of existing bombers. After some consideration, the original thinkers at De Havilland concluded that the best way to defend an aircraft wasn’t with bristling machine guns, but by making it so fast that nothing in the sky could catch it.
The approach seemed reasonable, so the design team continued to tinker with their wooden aircraft concept — though it still hadn’t received the blessing of the RAF. They discarded the gun turrets and four of the crew positions, a reduction which significantly decreased the estimated weight. They also paid close attention to the aerodynamics of the craft, aiming for a skin as slippery as that of a fighter plane. With its pair of supercharged Merlin engines, the lightweight plywood design was estimated to have a top speed of 400 miles per hour with a full bomb load, easily outpacing Germany’s fastest fighters.
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After some setbacks due to equipment shortages and German bombings of the De Havilland buildings, the Mosquito prototype was transported to the town of Hatfield for a test flight on 25 November 1940. Its final construction was heat-formed plywood over a wooden frame, with sections glued and screwed for extra strength. It employed Ecuadorean balsawood sandwiched with Canadian birch, a particularly strong and lightweight grade of plywood. Metal was used in only a few parts, including the engine housings and some control surfaces. The wooden sections were covered in fabric and the prototype was painted bright yellow to discourage British anti-aircraft crews from firing upon the top-secret airplane. A series of test flights over the following months confirmed that the Mosquito was an extremely agile and swift machine, executing impressive acrobatics and reaching speeds up to 392 miles per hour. Further testing also discovered that the aircraft could easily heft four times the load it had been designed for.Official attitudes towards the Mosquito quickly changed after observing the prototype in action. The RAF ordered a number of the aircraft in several configurations, including bombers, heavy fighters, and photo reconnaissance. De Havilland enlisted the assistance of carpenters, piano makers, cabinet builders, and other woodworkers who had been previously unable to make an appreciable contribution to the war effort. Sub-assemblies were constructed in places such as furniture factories, then sent to the De Havilland plant for final assembly in large concrete moulds. To speed production, engineers developed a technique where the glue was rapidly dried with the assistance of microwaves.
The unlikely wooden aircraft quickly established itself as one of the most useful planes in the Royal Air Force. The bomber varieties could deliver a payload comparable to that of the flying fortresses, while consuming less fuel, putting fewer lives in danger, and cruising at about twice the speed of the larger bombers. The Mosquito was also useful for low-altitude runs, where squadrons of Mosquitos flying at rooftop heights dropped their ordnance with precision, departing at full speed with German interceptors in hopeless pursuit.
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By the time the war was over, not only had the Mosquito proven itself to be capable, but in many ways extraordinary. These aircraft — primarily built by carpenters using commonplace materials — flew over 28,000 missions for Bomber Command, and only 193 of them were lost in the duration of the war. A Mosquito named F for Freddie held the record for the most bombing runs by a single aircraft in World War 2, having executed 213 sorties. The last Mosquito was built in 1950, and the Wooden Wonder remained the fastest aircraft in Bomber Command until 1951.Unfortunately the wood construction has not weathered the years as well as it weathered the war; only about thirty preserved specimens remain, and none are airworthy. The original prototype survived, however, and is currently undergoing complete restoration in the De Havilland Aircraft Heritage Centre in Hertfordshire, United Kingdom.