The Hanriot HD.20 was a French single seat shipboard

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 ...

prototype completed in 1923. Only one was built.

Design and development

The Hanriot HD.20 was an all-metal

two 2 (two) is a number, numeral and digit. It is the natural number following 1 and preceding 3. It is the smallest and the only even prime number. Because it forms the basis of a duality, it has religious and spiritual significance in many ...

bay biplane, though the inner bay was relatively narrow. Outward leaning 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, assisted by wire bracing, divided the bays. The wings had significant stagger and the lower plane had the greater span; in plan the wings were straight edged, unswept and of constant chord, with angled tips.

Ailerons 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 ...

were fitted only on the upper plane and were short span and overhung, that is, their horn balances projected beyond the wing tips. The HD.20 had a braced, rectangular

tailplane A tailplane, also known as a horizontal stabilizer, is a small lift (force), lifting surface located on the tail (empennage) behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed-wing aircraft such as helicopters ...

mounted on top of the fuselage and a small, curved edged

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 ...

. The

elevator An elevator (American English) or lift (Commonwealth English) is a machine that vertically transports people or freight between levels. They are typically powered by electric motors that drive traction cables and counterweight systems suc ...

s were balanced and the broad chord

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 ...

, which met the flat top of the fin almost vertically, reached down to the keel and moved within an elevator cut-out. The fighter was powered by a

Hispano-Suiza 8F The Hispano-Suiza 8 is a water-cooled V8 SOHC aero engine introduced by Hispano-Suiza in 1914 that went on to become the most commonly used liquid-cooled engine in the aircraft of the Entente Powers during the First World War. The original Hisp ...

b water-cooled upright

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 ...

. The pilot's 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 ...

was over the

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. ...

of the lower wing; both planes had central cut-outs to improve the pilot's view. A large Busteed inflatable buoyancy airbag between the

undercarriage Undercarriage is the part of a moving vehicle that is underneath the main body of the vehicle. The term originally applied to this part of a horse-drawn carriage, and usage has since broadened to include: *The landing gear of an aircraft. *The ch ...

legs was provided for emergency landings on the sea. The HD.20 had a fixed tailskid undercarriage, with mainwheels on a single axle mounted on the lower fuselage longerons by two pairs of V-struts. The HD.20 first flew in 1923 and flight testing explored its higher altitude performance, but then tests and development were ended.

Specifications

References

{{Hanriot aircraft Biplanes 1920s French fighter aircraft Hanriot HD.20 Aircraft with fixed conventional landing gear Single-engined piston aircraft