Messerschmitt M31

Messerschmitt M31
M31 with BMW Xa engine
Type:	Sports and training aircraft
Design country:	German Empire
Manufacturer:	BFW
First flight:	August 1932
Commissioning:	-
Number of pieces:	1

The Messerschmitt M31 was a German sports and training aircraft developed by Bayerische Flugzeugwerke AG in Augsburg in the early 1930s .

history

The M31 was founded in 1931 under the direction of Willy Messerschmitt as a successor of the developed light aircraft types M23 and M27 designed in the time of global economic crisis to create a geared at low cost of ownership pattern. For this reason, the aircraft was also equipped with a weaker and therefore cheaper engine than its predecessor. It was established with a copy of the drive number 607, which has a BMW - radial engine was equipped with a left-handed reduction gear and a NACA-hood is equipped. In the summer of 1932, the construction of the prototype was completed and at the beginning of August Erwin Aichele completed the first flight with the M31. The following flight test, which lasted several months, confirmed the calculated performance and flight characteristics, but no registration took place. In order to arouse the interest of potential buyers, the aircraft was instead subsequently presented at the German Air Sports Exhibition (DELA), which took place in Berlin from October 1 to 10, 1932 , but without success. The M31 therefore received a somewhat more powerful HM-60 in - line engine from Hirth in the spring of 1933 and was D–2623approved. However, when, after several months, there was still no buyer for the only M31 built, it was finally taken over by the Reich Aviation Ministry (RLM) in 1934 .

construction

The M31 was a cantilever low-wing aircraft in composite construction with a welded in trefoil fuselage frame of chrome - molybdenum - steel pipes , trapezoidal cross-section and a curved back. The two open crew cabins, one behind the other, were equipped with double controls for training tasks, whereby the flight instructor seated in front could take the control of the student behind him out of operation by turning his stick handle. Behind the crew rooms there was also a small storage space for luggage. The wings had a trapezoidal outline and consisted of a wooden frame with a main and auxiliary spar . The front edge of the surface was designed to be torsion- resistant, the cladding of the surface consisted of plywood paneling up to the auxiliary spar and fabric covering behind it. The tail unit was of normal construction and comprised the vertical fin made of tubular steel with the fabric-covered, wooden rudder as well as that of the wooden horizontal stabilizer , consisting of the adjustable, braced horizontal stabilizer with plywood cladding and the elevator with fabric covering.

The M31 had a rigid main wheel chassis with a split axle and low-pressure tires, which also served as suspension. A rotatable grinding spur was attached to the stern.

Technical specifications

Three-sided view with BMW Xa

Parameter	Data
crew	1-2
span	12.00 m
length	7.85 m
height	2.20 m
Wing area	17.24 m²
Wing extension	8.4
Wing loading	37.7 kg / m²
Preparation mass	350 kg
Payload	300 kg
Takeoff mass	650 kg
Drive 1	an air-cooled five-cylinder four-stroke radial engine BMW Xa
Starting power	68 hp (50 kW) at 2300 rpm
Drive 2	an air-cooled four-cylinder four - stroke in - line engine Hirth HM 60
Starting power max. Continuous output	70 hp (51 kW) at 2150 rpm 65 hp (48 kW) at 2000 rpm
Top speed	175 km / h
Cruising speed	150 km / h
Rise time	5.8 min at 1000 m altitude 27 min at 3000 m altitude
Service ceiling	3800 m
Range	700 km

literature

• Hans J. Ebert, Johann B. Kaiser, Klaus Peters: Willy Messerschmitt - pioneer of aviation and lightweight construction. In: German aviation. Volume 17, Bernard & Graefe, Bonn 1992, ISBN 3-7637-6103-9 , p. 85/86.
• Günter Brinkmann, Kyrill von Gersdorff, Werner Schwipps: Sports and travel aircraft. Guidelines for a diverse development. In: German aviation. Volume 23, Bernard & Graefe, Bonn 1995, ISBN 3-7637-6110-1 , p. 124.
• Manfred Griehl: Messerschmitt. Aircraft since 1925. In: Typenkompass. Motorbuch, Stuttgart 2008, ISBN 978-3-613-02980-4 , p. 31.

Web links

Commons : Messerschmitt M 31  - Collection of images, videos and audio files

Individual evidence

1. ↑ ^{a b} Kyrill von Gersdorff, Kurt Grasmann: Aircraft engines and jet engines. In: German aviation. Volume 2, Bernard & Graefe, Munich 1981, ISBN 3-7637-5272-2 , p. 56.