The Miles M.71 Merchantman[1][2] was intended to follow the successful Aerovan freighter as a larger aircraft built along similar lines.
Miles aimed to provide a simple, sturdy high-wing monoplane with an easily accessible and configurable cargo or passenger space.
[1][3] Unlike the Aerovan the Merchantman was intended to be a largely all-metal-framed aircraft,[1] though the first prototype and only example built had wooden tail surfaces for speed of construction.
The Merchantman's extra power came from both the number and choice of engines: it had four 250 hp (187 kW) de Havilland Gipsy Queen inverted inline motors.
On the other hand, it produced a large uncluttered space that could be readily accessed via rear doors that included an integral ramp[2] to the fuselage floor.
It had a tricycle undercarriage with stub axles mounted under the fuselage floor carrying short legs that bore a pair of small fixed main wheels, keeping the aircraft close to the ground for loading; the fuselage floor was only 2 ft (610 mm) above the ground.