The Vickers Wellesley light bomber

In the transition from biplanes to monoplanes, a single-engine, low-wing monoplane seemed like a reasonable configuration for light bombers in the the 1930's. The Vickers Wellesley, which was advanced in the sense of having Barnes Wallis's geodesic structure, was an early competitor. The Wellesley had a low-powered, air-cooled engine, which produced a top speed of about 238 mph. The Wellesley saw extensive service in the Middle East and Africa before being replaced by more advanced, twin-engined aircraft. Its load carrying ability and range allowed it to remain in service, despite its low top speed.