The Letov Š-7 was a single-seat, single-engine

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 ...

fighter aircraft Fighter aircraft (early on also ''pursuit aircraft'') are military aircraft designed primarily for air-to-air combat. In military conflict, the role of fighter aircraft is to establish air supremacy, air superiority of the battlespace. Domina ...

designed and built in

Czechoslovakia Czechoslovakia ( ; Czech language, Czech and , ''Česko-Slovensko'') was a landlocked country in Central Europe, created in 1918, when it declared its independence from Austria-Hungary. In 1938, after the Munich Agreement, the Sudetenland beca ...

in the early 1920s. It was designed for a single-seat fighter competition but did not reach production.

Design and development

The Letov Š-7 was designed for a 1923 government competition for a single-engine fighter, to be powered by a Škoda licence-built Hispano-Suiza 8Fb, 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. Origins The first known V8 was the Antoinette (manufactu ...

. It was a single-bay biplane, the bays defined by parallel pairs of

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 struts, which act in ...

s. The wings, mounted with modest stagger, were straight edged and had the same constant chord and blunt wingtips. The 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 aroun ...

s. Letov experienced some cooling problems with the Š-7's water-cooled engine. The aircraft as first flown had a ring-shaped

radiator A radiator is a heat exchanger 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 ...

, but this was replaced with a transversely mounted, circular cross-section

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

radiator and the engine

cowling A cowling (or cowl) is the removable covering of a vehicle's engine, most often found on automobiles, motorcycles, airplanes, and on outboard boat motors. On airplanes, cowlings are used to reduce drag and to cool the engine. On boats, cowlings ...

revised. The modification resulted in a change of designation to Letov Š-7a. The Hispano engine drove a two-blade

propeller A propeller (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 a working flu ...

with a domed

spinner Spinner may refer to: 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 ...

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

cockpit A cockpit or flight deck is the area, on the front part of an aircraft, spacecraft, or submersible, from which a pilot controls the vehicle. The cockpit of an aircraft contains flight instruments on an instrument panel, and the controls th ...

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 straight edged, cropped lozenge-shaped horizontal tail was mounted on the

fuselage The fuselage (; from the French language, French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds Aircrew, crew, passengers, or cargo. In single-engine aircraft, it will usually contain an Aircraft engine, engine as wel ...

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. F ...

and

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, airship, or other vehicle that moves through a fluid medium (usually air or water). On an airplane, the rudder is used primarily to counter adverse yaw ...

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 Ter ...

, with mainwheels on cross-braced V-struts. It was armed with a pair of 7.7 mm (0.303 in) machine guns, mounted in a dip in the engine cowling between the two cylinder banks, firing through the propeller arc. The Letov Š-7 first flew in 1923 but failed to gain orders and its development was discontinued.

Variants

;Letov Š-7: Original ring-shaped radiator. ;Letov Š-7a: Ventral radiator and modified cowling.

Specifications

References

{{DEFAULTSORT:Letov S-7 1920s Czechoslovak fighter aircraft Letov aircraft Single-engined tractor aircraft Biplanes Aircraft first flown in 1923