Letov LF-107 Lunak

LF-107 Luňák

File:Lunak02.jpg A Luňák over Southern Germany.
Type designation	LF-107 Luňák
Competition class	N/A
Number built	75
Crew	1
Length	6.78 m
Height
Cockpit width
Cockpit height
Wingspan	14.27 m
Wing area	13.38 m²
Aspect ratio	15.22
Wing profile	NACA 23012
Empty mass	ca. 205 kg
Maximum mass	310 kg
Wing loading	23.17 kg/m²
Maximum speed	300 km/h
Speed in turbulence
Maneuver speed
Stall speed	50 km/h
Minimum sink rate	ca. 0.85 m/s at 65 km/h
Best glide ratio	ca. 24 at 80 km/h
Acceleration limits

The LF-107 Luňák is a Czech aerobatic glider designed by Rudý Letov in the late 1940's. The design was developed within a prolific group of aeronautical engineers and sailplane pilots including among others K. Dlouhý, J. Matejcekm and B. Bocek.

The first flight of the prototype took place in June 25, 1948 and a second prototype flew in July. The prototype participated later in the same year in an aerobatic competition in Grenchen, Switzerland, and in Ziar, Poland in 1949, where its good aerobatic and gliding characteristics drew considerable attention.

Unfortunately the serial production was disrupted by geopolitical developments, as the factory was charged with production of MiG-15 and MiG-10 aircraft and the access to Western civil export markets was progressively hampered by the emergence of the Iron Curtain. Therefore, only 75 examples of the Luňák were produced in all.

In 1950, a variant with simpler construction and a revised cockpit, among other changes, was developed. This LF-107 Luňák of wooden construction, designated VT-7 under the military training system, was instrumental in the development of gliding and aerobatics in the Czech Republic. The LF-107 was also used for aerobatic training in the Soviet Union, Bulgaria, Romania and Poland.

The Letov XLF-207 Laminar, a derivative of the Luňák, holds the distinction of being the first glider in the world to have a laminar flow wing. Its maiden flight took place in Praha Letnany in August 1951.

Presently there are only nine airworthy Luňák, of which two are in the United Kingdom. A Luňák is displayed in the American Museum of Flight.

Sources

• German Wikipedia article [1]
• Peter Mallinson and Mike Woollard, Handbook of Glider Aerobatics

External links

• German site dedicated to the Luňák [2]
• Museum of Flight [3]

• Flying revue - LF 107 Luňák History (Czech) [4]

See also

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Letov LF-107 Lunak".