Messerschmitt M.21, M.22 и M.26
В период 1927-1930 годов В. Мессершмитт построил прототипы трех самолетов, но заказов на их серийное производство не получил.
Двухместный учебный M.21 фактически стал первым бипланом фирмы и предназначался для обучения военных летчиков. Построено было два прототипа, один с мотором Siemens Sh.11 мощностью 96 л. с., второй - с мотором Sh.12 мощностью 125 л. с.
Flight, October 1928
THE BERLIN AERO SHOW 1928
The B.F.W. Messerschmitt Light 'Planes
The Bavarian Aircraft Works of Augsburg exhibit two machines in the light 'plane class. Of these one is a two-seater biplane with Siemens S.H.11 engine, and the other is a low-wing monoplane two-seater with 20 h.p. Mercedes engine.
The B.F.W. type M.21 is an equal-span biplane designed for school work and aerobatics. Its aerodynamic design is perfectly normal (using the expression in the British sense) and the machine follows British practice in that the wings are designed to fold back, a feature not frequently found on German machines.
The flat-sided fuselage is of welded steel tube construction, without wire bracing, the struts being arranged diagonally to triangulate the structure. The wings are of wood construction, with ply-wood covering, but with normal interplane struts and wire bracing. As in British light 'planes the petrol tank forms the top centre-section, giving direct gravity feed to the carburettor. The cockpit arrangements are normal, with removable controls fitted in one cockpit so that when the machine is not being used for school work, the second set of controls can be taken out. The factors of safety are stated to be such that the machine may be used, in its two-seater form, for ordinary "stunting," while as a single-seater it is strong enough for the latest evolutions, such as the outside loop, etc.
The engine fitted in the B.F.W. M.21 is a Siemens radial, type S.H.11, but the designer informs us that if desired a different "nose" can be supplied to take the "Cirrus" engine.
Following are the main characteristics of the B.F.W. M.21: Length o.a., 7-32 m. (24 ft.); wing span, 10 m. (32-8 ft.); wing area, 20-8 sq. m. (224 sq. ft ) Tare weight, 460 kg. (1,012 lbs.); permissible load, 280 kg. (616 lbs.); total loaded weight, 740 kg. (1,623 lbs.); Maximum speed 145 km./h. (90 m.p.h.); cruising speed, 130 km./h. (81 m.p.h.). Ceiling, 3,300 m. (10,800 ft.). Range, 500 km. (310 miles).