The Weymann W-1 was a French single seat

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 ...

, built during

World War I World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

. It had a most unusual layout, with an engine buried in 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 ...

driving a

pusher configuration In aeronautical and naval engineering, pusher configuration is the term used to describe a drivetrain of air- or watercraft with propulsion device(s) after the engine(s). This is in contrast to the more conventional tractor configuration, wh ...

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 ...

behind a

cruciform tail The cruciform tail is an aircraft empennage configuration which, when viewed from the aircraft's front or rear, looks much like a cross. The usual arrangement is to have the tailplane, horizontal stabilizer intersect the vertical tail somewhere ...

. It was not successful and soon abandoned.

Design

Apart from its rear mounted pusher propeller, shaft driven from a centrally mounted engine, the W-1 was unusual in other respects. It was an all-metal aircraft; a single bay biplane with constant chord, equal span, unswept and unstaggered wings, braced by parallel

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

flying wire 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. There were

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 on both upper and lower planes, externally connected. The deep, flat sided and flat topped fuselage entirely filled the interwing space, with the pilot's open cockpit immediately level with and ahead of the upper wing

leading edge The leading edge is the part of the wing that first contacts the air;Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 305. Aviation Supplies & Academics, 1997. alternatively it is the foremost edge of an airfoil sectio ...

. He had twin machine guns faired into the upper surface ahead of him and, beyond, a smooth, rounded nose. The absence of engine and propeller gave him a good forward view and avoided the need for engine-gun synchronisation. The engine was behind him at the aircraft's

centre of gravity In physics, the center of mass of a distribution of mass in space (sometimes referred to as the barycenter or balance point) is the unique point at any given time where the weighted relative position of the distributed mass sums to zero. For a ...

(cg), totally enclosed within the fuselage. An intake into the underside of the fuselage immediately below the cockpit provided cooling air for the Clerget 7Z

rotary engine The rotary engine is an early type of internal combustion engine, usually designed with an odd number of cylinders per row in a radial configuration. The engine's crankshaft remained stationary in operation, while the entire crankcase and its ...

, which had an exhaust in the upper fuselage. The fuselage tapered both in height and width to the tail, where the

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 ...

and split

elevators An elevator (American English) or lift (English in the Commonwealth of Nations, Commonwealth English) is a machine that vertically transports people or freight between levels. They are typically powered by electric motors that drive tracti ...

were mounted on its upper surface. The upper

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 ...

was quite short but the lower part extended well below the lower wing in level flight. All the tail surfaces had curved leading edges; the two blade propeller was immediately behind their straight

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. ...

s. The W-1's undercarriage was also unusual. Though the mainwheels were conventionally positioned close to the cg and mounted on a rigid single axle attached to the fuselage by a pair of V-struts, it had a nosewheel of about the same diameter; unlike that of modern

tricycle gear Tricycle gear is a type of aircraft undercarriage, or ''landing gear'', that is arranged in a tricycle fashion. The tricycle arrangement has one or more nose wheels in a single front undercarriage and two or more main wheels slightly aft of th ...

it was well above the ground when the aircraft was in the level flight position. On the ground the W-1 rested level on its mainwheels and a tailskid on the tall lower fin. The W-1 made only two short test flights, the first in the autumn of 1915, which revealed severe and ultimately insurmountable cooling problem with the buried engine. The development programme was abandoned in December 1915.

Specifications

References

{{Weymann aircraft W-1 Single-engined pusher aircraft Biplanes 1910s French fighter aircraft Rotary-engined aircraft Aircraft first flown in 1915