Let L-40 MetaSokol
Country of Origin
Three/four seat light aircraft
One of the more lesser known light aircraft to emerge from behind the Iron Curtain, the unusually configured MetaSokol three/four seat light aircraft was a development of the Let Mraz M.1 Sokol. The M.1 Sokol was a three seat light aircraft developed in the late 1940s. It was used in a variety of roles, mainly for training and a number were built for Czechoslovak flying schools. The wooden construction M.1 Sokol featured tail dragger undercarriage and a 80kW (105hp) Walter Minor 4III inline inverted four cylinder engine. Like the M.1 Sokol, early production MetaSokols seated three and were powered by the same 80kW (105hp) Walter Minor engine. However the MetaSokol introduced a number of new features and design changes including metal construction, a rearwards sliding cockpit canopy, a very tall vertical tail that extends from the fuselage at almost a right angle, and a unique undercarriage system. The MetaSokol's undercarriage features a reverse tricycle arrangement, with the main undercarriage legs extending from the front of the wing, with the third leg mounted from under the fuselage. Unlike the original fixed undercarriage M.1 Sokol, the MetaSokol's undercarriage retracts, although the rearward retracting main landing gear remains exposed in flight. The prototype L20 MetaSokol flew for the first time during 1954. This original three seat model was built in only small numbers before it was superseded by the definitive four seater, which also introduced a more powerful M332 engine. The M332 was notable in that its normal maximum power output could be boosted for up to five minutes with supercharging. Like the majority of Eastern European aircraft of its time, most MetaSokols were exported to countries within the Soviet sphere of influence, although a number were sold in western Europe, North America and Australia.
Late production aircraft - One 85kW (115hp) with 5 min supercharged 105kW (140hp) rating Walter M332 inline inverted four cylinder piston engine driving a two blade adjustable pitch propeller.
Late production aircraft - Max speed 237km/h (128kt), max cruising speed 208km/h (112kt). Initial rate of climb 630ft/min. Service ceiling 14,765ft. Max range 850km (460nm).
Late production aircraft - Empty 520kg (1147lb), max takeoff 920kg (2030lb).
Late production aircraft - Wing span (without wingtip tanks) 10.00m (32ft 10in), length 7.54m (28ft 9in), height 2.47m (8ft 1in). Wing area 14.6m2 (156.0sq ft).
Initial production aircraft had seating for three with a single passenger seated behind pilot and passenger. Late production had seating for four.
Approximately 200 MetaSokols built between 1954 and 1961. Almost all production was of the four seat model, with only small numbers of the initial three seat model built.
Let L-40 MetaSokol
The backbone of this section is from the The International Directory of Civil Aircraft by Gerard Frawley and used with permission. To get your own copy of the book click here.