The Mosquito Bomber

Although Radio Berlin first announced capture of a Mosquito bomber more than six months ago, official reticence and a tight-lipped British press prevented any mention of this newest British raider until the Oslo daylight raids which immediately preceded the Allied African offensive. Thus, observers are generally convinced that at least one of these fast-flying twin-engine bombers was lost in the first-mentioned operations, inasmuch as the British have, throughout three war years, announced details on new planes only after one or more specimens were downed by the enemy in recognizable condition. But the fact that it took Germany at least six months to accomplish this minor conquest speaks highly for the operational efficiency of the Mosquito, a stepped up fighting companion to the DeHavilland Comet which captured the England-Australia race in 1934.

Designed and built by the DeHavilland Aircraft Company, Ltd, the Mosquito is officially classed as a reconnaissance bomber. But its clean lines, epitomized by nacelle fairing which creates little turbulence on upper wing surface, bear little resemblance to any other plane of this type now in service. The two Rolls Royce liquid-cooled engines are completely under-slung, with landing gear retracting straight backward into the nacelles to create exceptionally low drag on power plant emplacements. In this latter feature, informed observers see greatest resemblance between the Mosquito and the DeHavilland Comet of eight years ago.

Piloted by C W A Scott and T Campbell-Black, the latter ship won the England-Australia race, getting close competition from the only other Comet ever built, which was flown by Jim Mollison. That the earlier plane was a low-wing monoplane while the Mosquito has wing mounted half-way up the fuselage sides can be explained by operational purpose which must provide internal bomb stowage while the Comet was fitted with fuel tanks in the fuselage fore section. It might also be observed that the two-place Comet crew occupied cockpits far back on the fuselage, an expedient which admittedly reduced visibility but placed the center of gravity in racing-plane position. Obviously, combat requirements dictated the Mosquito's cabin position far forward in the rounded nose section.

Beyond these mandatory external changes, the planes are almost identical in basic precept, with the Mosquito nothing more nor less than a scaled-up version of the 1934 Comet which ranked as one of the cleanest designs of the day. DeHavilland has apparently utilized the low drag factors of this design in two ways — to add both speed and range to the Mosquito's bag of military tricks. As far back as 1935 Captain Hubert Broad, then chief test pilot with DeHavilland, had argued that minor changes would fit the Comet racer for military duty, suggesting specifically that the fuel tanks which then carried 258 gallons might well be replaced with a single large bomb. As a single-seat bomber, this two-place design could carry the 500-pound bomb more than 2,200 miles with the 1,500-pound fuel load still available.

Powered by two DeHavilland Gipsy Six R engines, developing a total of 460 hp, the Comet had maximum speed in the neighborhood of 230 mph. Relatively slow by today's standards, that performance actually topped the speed of any bombing plane in British service at the time. More important, one-place Comet bombers could have been built in large quantities at low cost — an important consideration in the depression year of the Comet's birth. Beyond the increase in power resulting from present use of Rolls Royce engines in the Mosquito, the planes still bear close resemblance in engine appearance and installation. The landing gear on the Mosquito is actually cleaner than the undercarriage used on the Comet, for the former is fitted with retractable tail wheel as well as backward retracting main gear. And the Comet was fitted with one of the first variable pitch propellers, forerunners of the airscrews now used on the Mosquito.

In the plan form of the wings, principal point of divergence between the designs is apparent in the rounded tips on the Mosquito. Otherwise, the wings are identical in chord and taper. Racing plane addicts may recall that the Comet attracted some note for having the thinnest wing ever used on a cantilever monoplane, getting necessary strength from a special type of plywood construction in which spruce strips were laid diagonally across the wings from leading to trailing edge, with the number of layers increasing near the root where stresses were greatest. Besides giving extremely clean external surfaces this type of construction lends itself to prefabrication and wide dispersal of actual manufacture throughout England and Canada, with factories in the Dominion ideally situated close to lumber sources.

In regard to previous mention of the Mosquito as a scaled up version of the Comet, the full significance of this increase in size can best be obtained from consideration of actual specifications. The Comet had a wing span of 44' and measured 29' in overall length. The Mosquito has a wing span of 54' 2" and is 40' 10" long. Although further details of equipment and performance on the Mosquito cannot be printed at this time, its operational excellence can be presumed from power plant and general size. Armament probably consists of four 20-mm cannon and four .303-cal machine guns. Altogether, Capt G DeHavilland, specialist in civil plane manufacture for many years, has produced an important weapon for the Allies in his first military design of World War II.

Captain DeHavilland recently demonstrated the Mosquito to US Army officials at Bolling Field near Washington, DC. He shocked orthodox pilots by cutting the switch on one engine, feathering the prop and crossing the field at a low altitude, slow-rolling as he flew. The ship's phenomenally light weight accounts for its performance.

This article was originally published in the January, 1943, issue of Air News magazine, vol 4, no 1, pp 60-62.
The original article includes 7 photos: 1 Comet and 6 Mosquito.
5 Photos are credited to International British Combine; 2 are not credited.

Mosquito photos: