The M 23 was an advanced successor to the trainer and sports biplane U 12 Flamingo. This aircraft had enjoyed a very successful production run at BFW. It was supposed to be cheaper to manufacture, while combining similar good flight characteristics with a much more advanced design and construction, as well as delivering higher power. In the winter of 1927/28, Willy Messerschmitt initially designed a two-seater low-wing plane with a pentagonal fuselage mounted on a continuous wing. A Mercedes-Benz F 7502 engine delivering 18 kW power was envisaged as the power unit. This substantially underpowered aircraft is reputed never to have taken to the air. It was only presented to a public audience at the Aero Salon in Paris during June/July of the same year.
Three more airframes were quickly produced between March and July 1928 to meet the obvious need to install a more powerful engine. The cantilevered single-spar wing was also integrated in the fuselage. Initially, the low-wing aircraft designated M 23a served mainly to test foreign engines with different power ratings. The third aircraft fitted with an Armstrong-Siddeley Genet radial engine delivering power of 44 kW took part in the East Prussian Challenge in 1928/29. The aircraft came out well in the technical tests and the crew Croneiß/Fitzek also won the long-distance race in March 1929. Intensive promotion and demonstration flights combined with this racing success led to the manufacture of a small production run of nine M 23a aircraft.
Messerschmitt already started further development work on the design of the aircraft in autumn 1928. The M 23b emerged with a strengthened fuselage framework and cast landing-gear rims, and a rounded top to the fuselage. The M 23b took off on its maiden flight at the end of March 1929. BFW started mass production in early summer and registered nine aircraft to take part in the Round Europe Challenge. One of the aircraft fitted with a Siemens & Halske Sh 13 five-cylinder radial engine delivering power of 59 kW and crewed by Morzik/Schiel brought the challenge cup to Germany for the first time. Thanks to this success and their outstanding flight characteristics, more than 70 aircraft had been sold by the end of 1931. The reputation of Willy Messerschmitt and his sports aircraft designs was assured for the future. Most importantly, the M 23b also enhanced its reputation with the success of Ernst Udet’s expeditions flying across Africa from November 1930 to April 1931 and by their joint appearance in the film SOS Eisberg which ended with a planned crash landing.
The M 23c was designed to meet the competition conditions for the Round Europe Challenge in 1930. Compared with the previous model, the fuselage structure was further strengthened and the front fuselage section was entirely designed in a lightweight all-metal construction. The aircraft also had a glazed cockpit cover. A total of eleven aircraft were built at BFW and one of these aircraft flown by Fritz Morzik again triumphed as overall winner in the Round Europe Challenge. The aircraft were fitted with a Siemens & Halske Sh 13 radial engine delivering power of 70 kW or an Argus As 8 inline engine delivering 74 kW power.
