The Piel CP-40 Donald is a French

homebuilt Homebuilt machines are machines built outside of specialised workshops or factories. This can include different things such as kit cars or homebuilt computers, but normally it pertains to homebuilt aircraft, also known as amateur-built aircraft or ...

, single engine, single seat,

high wing A monoplane is a fixed-wing aircraft A fixed-wing aircraft is a heavier-than-air aircraft, such as an airplane, which is capable of flight using aerodynamic lift. Fixed-wing aircraft are distinct from rotary-wing aircraft (in which a r ...

aircraft. It was first flown in the early 1950s, though the last of the three examples completed did not fly until almost forty years later.

Design and development

The Donald is a conventionally laid-out single engine, braced

monoplane 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 wings. A monoplane has inherently the highest efficiency and lowest drag of any wing con ...

. Its low

aspect ratio The aspect ratio of a geometry, geometric shape is the ratio of its sizes in different dimensions. For example, the aspect ratio of a rectangle is the ratio of its longer side to its shorter side—the ratio of width to height, when the rectangl ...

(5.1) wings are unswept and of constant chord, with blunt, rounded tips; they carry short, broad

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 but no

flap Flap may refer to: Arts, entertainment, and media * ''Flap'' (film), a 1970 American film * Flap, a boss character in the arcade game '' Gaiapolis'' * Flap, a minor character in the film '' Little Nemo: Adventures in Slumberland'' Biology and h ...

s. There are V-form struts between the wing and lower

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 ...

on each side. At the rear the vertical surfaces are rounded and the

balanced rudder Balanced rudders are used by both ships and aircraft. Both may indicate a portion of the rudder surface ahead of the hinge, placed to lower the control loads needed to turn the rudder. For aircraft the method can also be applied to elevator (air ...

extends down to the keel. The horizontal tail is tapered with rounded tips and 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 have a cut-out for rudder movement. Behind the engine the fuselage is flat sided. The pilot's windscreen is just ahead of the 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 ...

but the side glazing of the single-seat cabin extends back to about two-thirds chord. The cabin roof extends into raised rear fuselage decking, which drops away slowly to the tail. The Donald has a tailskid undercarriage with main wheels mounted on split axles, hinged on a shallow V-strut attached to the fuselage underside. Faired, tapered legs are mounted on the lower fuselage

longeron In engineering, a longeron or stringer is a load-bearing component of a framework. The term is commonly used in connection with aircraft fuselages and automobile chassis. Longerons are used in conjunction with stringers to form structural fram ...

s. The first prototype, with only from its Volkswagen 1.1-litre air-cooled

flat-four engine A flat-four engine, also known as a horizontally opposed-four engine or boxer engine, is a four-cylinder piston engine with two banks of cylinders lying on opposite sides of a common crankshaft. The most common type of flat-four engine is the box ...

, first flew on 16 June 1953. Two other Donalds were homebuilt from plans by different amateurs. These were chiefly distinguished by the choice of air-cooled flat-four engine, most of which were Volkswagen based. Engine details, dates and type numbers are given below. The last built, the CP-402 no.9 ''F-PRAK'', was still on the French civil register in 2014, having moved to

Angers Angers (, , ;) is a city in western France, about southwest of Paris. It is the Prefectures of France, prefecture of the Maine-et-Loire department and was the capital of the province of Duchy of Anjou, Anjou until the French Revolution. The i ...

in 2005.

Variants

''Data from'' Massé (2004) and Gaillard (1990) ;CP-40: First prototype with Volkswagen 1.1-litre air-cooled

. First flight 16 June 1953. ;CP-41: CP-40 re-engined in 1959 with a Percy engine. ;CP-401: Second aircraft, with a

Continental A65 The Continental O-170 engine is the collective military designation for a family of small aircraft engines, known under the company designation of A50, A65, A75 and A80. The line was designed and built by Teledyne Continental Motors, Continental ...

air-cooled flat-four engine. First flight 25 August 1970. ;CP-402: CP-401 re-engined in 1977 with a Rectimo engine, based on a Volkswagen engine-block. ;CP-402 no.9: Third aircraft, with a Volkswagen 1.6-litre air-cooled

. Wing angle of incidence 4.5°, rather than 2.0°. First flown in 1992.

Specifications (CP-402 no.9)

References

{{Piel aircraft Piel aircraft 1950s French sport aircraft Homebuilt aircraft High-wing aircraft Single-engined tractor aircraft Aircraft first flown in 1953 Single-engined piston aircraft Aircraft with fixed conventional landing gear