The Klemm Kl 151 was a German prototype light passenger aircraft designed by Dr. Hanns Klemm and chief engineer Carl Bucher during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

. Only one model was built.

Development

In 1940 Klemm received a request from the

Reich Air Ministry The Ministry of Aviation (german: Reichsluftfahrtministerium, abbreviated RLM) was a government department during the period of Nazi Germany (1933–45). It is also the original name of the Detlev-Rohwedder-Haus building on the Wilhelmstrass ...

(RLM) chief

Ernst Udet Ernst Udet (26 April 1896 – 17 November 1941) was a German pilot during World War I and a ''Luftwaffe'' Colonel-General (''Generaloberst'') during World War II. Udet joined the Imperial German Air Service at the age of 19, and eventually ...

to begin work on a version of the

Messerschmitt Bf 108 The Messerschmitt Bf 108 ''Taifun'' (English: "Typhoon") was a German single-engine sport and touring aircraft, developed by Bayerische Flugzeugwerke in the 1930s. The Bf 108 was of all-metal construction. Design and development Originally desi ...

''Taifun'' using wood rather than aluminium for the airframe, since the metal was then in short supply. One of the conditions was that the design of the Bf 108 would be used for the new aircraft. This created substantial difficulties. To speed up the project both the wings and the fuselage were based on already-built

Kl 107 The Klemm Kl 107 was a two-seat light aircraft developed in Germany in 1940. It was a conventional low-wing cantilever monoplane of wooden construction with fixed tailwheel undercarriage. Wartime production totalled only five prototypes and some ...

components. Since the fuselage was too short, Bucher extended it at the tail with a welded tubular steel framework covered with sheet metal, which also housed the tail landing gear. The wings were widened at the root and moved forward in order to accommodate additional fuel tanks, which replaced the two rear seats.

Flight tests

The prototype Kl 151 V1, designated with the ''Stammkennzeichen'' radio code of TB+QK, made its first flight at

Böblingen Böblingen (; Swabian: ''Beblenga'') is a town in Baden-Württemberg, Germany, seat of Böblingen District. Sindelfingen and Böblingen are contiguous. History Böblingen was founded by Count Wilhelm von Tübingen-Böblingen in 1253. Württ ...

on 10 September 1942, with Klemm's chief pilot Karl Voy at the controls. The aircraft was powered by a 240

Pferdestärke Horsepower (hp) is a unit of measurement of power, or the rate at which work is done, usually in reference to the output of engines or motors. There are many different standards and types of horsepower. Two common definitions used today are the ...

(PS) (236 horsepower, 176 kW)

Argus As 10 The Argus As 10 was a German-designed and built, air-cooled 90° cylinder bank-angle inverted V8 "low power" aircraft engine, used mainly in training aircraft such as the Arado Ar 66 and Focke-Wulf Fw 56 Stösser and other small short-range re ...

P inverted V8 engine. The planned model Kl 151-B, fitted with a 355 PS (350 hp, 261 kW)

Argus As 410 The Argus As 410 was a German air-cooled inverted V-12 light aircraft engine that was first produced by Argus Motoren in 1938. Design and development The engine marked a departure from earlier Argus engines in that it had new construction tech ...

inverted V12 engine was not built. On 19 February 1943 the V1 prototype was transferred to the ''Deutsche Versuchsanstalt für Luftfahrt'' ("German Experimental Institute for Aviation") at

Adlershof Adlershof (, literally "Eagle's Court") is a locality (') in the borough (') Treptow-Köpenick of Berlin, Germany. Adlershof is home to the new City of Science, Technology and Media ( WISTA), located on the southwestern edge of the locality. His ...

for testing, which was successfully completed on 1 March 1943. The fixed undercarriage was a concern to the

Luftwaffe The ''Luftwaffe'' () was the aerial-warfare branch of the German '' Wehrmacht'' before and during World War II. Germany's military air arms during World War I, the '' Luftstreitkräfte'' of the Imperial Army and the '' Marine-Fliegerabt ...

, as the Bf 108 had suffered on the rough landing fields of the eastern front. Therefore, the requirement now demanded a robust as well as a retractable undercarriage. In place of the fixed tricycle undercarriage, now the V1 received one in a Y-configuration, with two steel half-shells welded together for the guidance of the shock absorbers on each side. Further testing continued. Klemm used the aircraft as a personal transport until July 1944, when it was destroyed in an Allied air raid. The Air Ministry transferred the incomplete V2 prototype, and responsibility for further development and production, over to the Czech company Zlin. The problems caused by the demand for a retractable landing gear were finally solved, but the aircraft was never completed, nor put into full production. After the war a revival of the project was considered, however Klemm instead decided on the

Specifications (Kl 151 V1)

Development

Flight tests

Specifications (Kl 151 V1)

Notes and references

See also