The Letov Š-13 was a single-seat, single-engine

fighter aircraft Fighter aircraft are fixed-wing military aircraft designed primarily for air-to-air combat. In military conflict, the role of fighter aircraft is to establish air superiority of the battlespace. Domination of the airspace above a battlefield ...

designed and built in

Czechoslovakia , rue, Чеськословеньско, , yi, טשעכאסלאוואקיי, , common_name = Czechoslovakia , life_span = 1918–19391945–1992 , p1 = Austria-Hungary , image_p1 ...

in the early 1920s. A

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...

, it had aerodynamically thick wings which were originally

cantilever A cantilever is a rigid structural element that extends horizontally and is supported at only one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a canti ...

structures, though

interplane strut In aeronautics, bracing comprises additional structural members which stiffen the functional airframe to give it rigidity and strength under load. Bracing may be applied both internally and externally, and may take the form of strut, which act in ...

s were later added. Only one was produced.

Design and development

The Letov Š-13 was designed as a

, its Zhukovsky

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. ...

wings thick enough in section to allow internal bracing. In other ways it much resembled the 1923

Letov Š-7 The Letov Š-7 was a single-seat, single-engine biplane fighter aircraft designed and built in Czechoslovakia in the early 1920s. It was designed for a single-seat fighter competition but did not reach production. Design and development The L ...

. The wings, mounted with modest stagger, were straight edged with constant chord and blunt

wingtip 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 ...

s. The slightly broader chord upper wing was braced to the fuselage with a cabane, formed on each side by a forward parallel pair of struts from the mid-fuselage, and a rear inverted-V pair from the upper fuselage. Only the lower planes carried

aileron An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...

s. Both the Š-7 and the Š-13 were powered by a Škoda licence-built

Hispano-Suiza 8F The Hispano-Suiza 8 was a water-cooled V8 SOHC aero engine introduced by Hispano-Suiza in 1914, and was the most commonly used liquid-cooled engine in the aircraft of the Entente Powers during the First World War. The original Hispano-Suiza 8A ...

b, a water-cooled

V-8 engine A V8 engine is an eight-cylinder (engine), cylinder piston engine in which two banks of four cylinders share a common crankshaft and are arranged in a V engine, V configuration. The first V8 engine was produced by the French Antoinette_(manuf ...

. Letov had experienced cooling problems with it in the Š-7 and so the ring-shaped

radiator Radiators are heat exchangers used to transfer thermal energy from one medium to another for the purpose of cooling and heating. The majority of radiators are constructed to function in cars, buildings, and electronics. A radiator is always a ...

proposed originally for the Š-13 was dropped and replaced from the start with the transversely mounted, circular cross-section

ventral Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. Th ...

radiator successfully tested on the modified Letov Š-7a. The Hispano drove a two-blade

propeller A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon ...

with a domed

spinner Technology *Spinner (aeronautics), the aerodynamic cone at the hub of an aircraft propeller * Spinner (cell culture), laboratory equipment for cultivating plant or mammalian cells * Spinner (computing), a graphical widget in a GUI * Spinner (MIT Med ...

. Behind the engine, the fuselage had an oval cross-section, with the single open

cockpit A cockpit or flight deck is the area, usually near the front of an aircraft or spacecraft, from which a Pilot in command, pilot controls the aircraft. The cockpit of an aircraft contains flight instruments on an instrument panel, and the ...

partially under the wing

trailing edge The trailing edge of an aerodynamic surface such as a wing is its rear edge, where the airflow separated by the leading edge meets.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 521. Aviation Supplies & Academics, 1997. ...

which had a shallow cutout to enhance his view. The fuselage tapered rearwards to a point behind the tail control surfaces. The cropped, straight tapered horizontal tail was mounted on the

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 ...

centreline; the

fin A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. Fin ...

and

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally aircraft, air or watercraft, water). On an aircraft the rudder is used primarily to ...

, larger than on the Š-7, were also straight edged. The Š-7 had a fixed, single-axle

conventional undercarriage Conventional landing gear, or tailwheel-type landing gear, is an aircraft undercarriage consisting of two main wheels forward of the center of gravity and a small wheel or skid to support the tail.Crane, Dale: ''Dictionary of Aeronautical Term ...

, with mainwheels on cross-braced V-struts, assisted by a tailskid. The Letov Š-13 first flew in 1924 in cantilever configuration but during the early flight trials concern about wing strength led to its conversion into a single bay biplane by the addition of a pair of

s. These were initially N-shaped but later changed to Vs. The trials demonstrated generally good handling characteristics but stability problems brought an end to development.

Specifications

References

{{DEFAULTSORT:Letov S-13 1920s Czechoslovakian fighter aircraft Letov aircraft Single-engined tractor aircraft Biplanes Aircraft first flown in 1924