The LAK-12 is a

Lithuania Lithuania (; lt, Lietuva ), officially the Republic of Lithuania ( lt, Lietuvos Respublika, links=no ), is a country in the Baltic region of Europe. It is one of three Baltic states and lies on the eastern shore of the Baltic Sea. Lithuania ...

mid-wing A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple planes. A monoplane has inherently the highest efficiency and lowest drag of any wing confi ...

, single-seat,

FAI Open Class Competition classes in gliding, as in other sports, mainly exist to ensure fairness in competition. However the classes have not been targeted at fostering technological development as in other sports. Instead classes have arisen because of: * t ...

glider Glider may refer to: Aircraft and transport Aircraft * Glider (aircraft), heavier-than-air aircraft primarily intended for unpowered flight ** Glider (sailplane), a rigid-winged glider aircraft with an undercarriage, used in the sport of glidin ...

that was designed and produced by Lietuviškos Aviacinės Konstrukcijos (LAK) ( en, Lithuanian Aircraft Builders) in

and later by Sportine Aviacija and Sport Aviation USSR.

Design and development

The LAK-12 was designed in the 1980s as an open class racer. The aircraft is made from

fibreglass Fiberglass (American English) or fibreglass (Commonwealth English) is a common type of fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened into a sheet called a chopped strand mat, or woven into glass clo ...

, foam and

carbon fibre Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon compo ...

. Its span foam-core wing employs a Wortmann FX67-K-170

airfoil An airfoil (American English) or aerofoil (British English) is the cross-sectional shape of an object whose motion through a gas is capable of generating significant lift, such as a wing, a sail, or the blades of propeller, rotor, or turbine. ...

at the

wing root The wing root is the part of the wing on a fixed-wing aircraft or winged-spaceship that is closest to the fuselage,Peppler, I.L.: ''From The Ground Up'', page 9. Aviation Publishers Co. Limited, Ottawa Ontario, Twenty Seventh Revised Edition, 1996 ...

, transitioning to a FX67- K-150 section at the

wing tip A wing tip (or wingtip) is the part of the wing that is most distant from the fuselage of a fixed-wing aircraft. Because the wing tip shape influences the size and drag of the wingtip vortices, tip design has produced a diversity of sha ...

. The wings feature both double-panel upper surface air brakes and flaps that can be set to -7°, -4°, 0°, +5°, +11° and +15°. Water ballast is held in the wing

leading edge The leading edge of an airfoil surface such as a wing is its foremost edge and is therefore the part which first meets the oncoming air.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 305. Aviation Supplies & Academics, ...

s and dumped through a centre-

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...

valve. The

landing gear Landing gear is the undercarriage of an aircraft or spacecraft that is used for takeoff or landing. For aircraft it is generally needed for both. It was also formerly called ''alighting gear'' by some manufacturers, such as the Glenn L. Martin ...

is a single retractable monowheel suspended by an oil/nitrogen oleo, plus a tailskid. The cockpit

canopy Canopy may refer to: Plants * Canopy (biology), aboveground portion of plant community or crop (including forests) * Canopy (grape), aboveground portion of grapes Religion and ceremonies * Baldachin or canopy of state, typically placed over an a ...

is of one-piece and forward hinged.

Operational history

According to Sportine Aviacija, the current type certificate holder, 253 were manufactured over a twenty-five year production run. In April 2018 there were 17 LAK-12s listed on the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

Federal Aviation Administration The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic m ...

registry Registry may refer to: Computing * Container registry, an operating-system-level virtualization registry * Domain name registry, a database of top-level internet domain names * Local Internet registry * Metadata registry, information system for re ...

, all single-place and certified in the ''Experimental - Racing/Exhibition'' category and three registered with

Transport Canada Transport Canada (french: Transports Canada) is the department within the Government of Canada responsible for developing regulations, policies and services of road, rail, marine and air transportation in Canada. It is part of the Transportati ...

in the ''Limited Class''.

Variants

;LAK-12 Lietuva: span open-class sailplane. ;LAK-12 Lietuva 2R:Two-seat version of the LAK-12 with tandem cockpit in an extended fuselage. ;LAK-12E: Experimental span variant built in 1988 and tested in 1988 and 1989, incorporating boundary control via blowholes on the lower surface. Only one produced.

Aircraft on display

The sole LAK-12E currently hangs from the ceiling of the Lithuanian Aviation Museum in Kaunas.

Specifications (LAK-12)

References

External links

{{LAK aircraft 1980s Lithuanian sailplanes LAK aircraft Glider aircraft Aircraft first flown in 1986