The Coelho AC-11 (also called the AC.11 and AC 11) is a Brazilian

homebuilt aircraft Homebuilt aircraft, also known as amateur-built aircraft or kit planes, are constructed by persons for whom this is not a professional activity. These aircraft may be constructed from "scratch", from plans, or from assembly kits.Armstrong, Kenn ...

that was designed and produced by Altair Coelho of Eldorado do Sul and introduced in 1994. The aircraft was intended to be supplied as a kit for amateur construction, but only one was completed.Purdy, Don: ''AeroCrafter - Homebuilt Aircraft Sourcebook, Fifth Edition'', page 344. BAI Communications, 15 July 1998. Altair Coelho
AC 11
, retrieved 14 April 2015

Design and development

The aircraft features a V- strut-braced

low-wing 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 planes. A monoplane has inherently the highest efficiency and lowest drag of any wing confi ...

, a two-seats-in-

side-by-side configuration Tandem, or in tandem, is an arrangement in which a team of machines, animals or people are lined up one behind another, all facing in the same direction. The original use of the term in English was in ''tandem harness'', which is used for two ...

enclosed cockpit, fixed

tricycle landing gear Tricycle gear is a type of aircraft undercarriage, or ''landing gear'', arranged in a tricycle fashion. The tricycle arrangement has a single nose wheel in the front, and two or more main wheels slightly aft of the center of gravity. Tricycle g ...

or optionally

conventional landing gear 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 ...

and a single engine in

tractor configuration In aviation, the term tractor configuration refers to an aircraft constructed in the standard configuration with its engine mounted with the propeller in front of it so that the aircraft is "pulled" through the air. Oppositely, the pusher co ...

. The aircraft

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 aircraf ...

is made from welded steel tube, while the wing is plywood, with some surfaces covered in doped

aircraft fabric Aircraft fabric covering is a term used for both the material used and the process of covering aircraft open structures. It is also used for reinforcing closed plywood structures. The de Havilland Mosquito is an example of this technique, as are ...

and some covered in plywood. Its span wing has a wing area of and employs a NACA 4412 airfoil. The cabin width is . The acceptable power range is and the engine used for the prototype was a

Volkswagen air-cooled engine The Volkswagen air-cooled engine is an air-cooled, gasoline-fuelled, boxer engine with four horizontally opposed cast-iron cylinders, cast aluminum alloy cylinder heads and pistons, magnesium-alloy crankcase, and forged steel crankshaft and ...

with a steel-pulley and

polyurethane Polyurethane (; often abbreviated PUR and PU) refers to a class of polymers composed of organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane is produced from ...

chain-driven 2:1

reduction drive A reduction drive is a mechanical device to shift rotational speed. A planetary reduction drive is a small scale version using ball bearings in an epicyclic arrangement instead of toothed gears. Reduction drives are used in engines of all kinds ...

. The aircraft has a typical empty weight of and a gross weight of , giving a useful load of . With full fuel of the payload for pilot, passenger and baggage is . The standard day, sea level, no wind, take off with a engine is and the landing roll is . The manufacturer estimated the construction time of the prototype as 1600 hours.

Operational history

By 1998 the company reported that one conventional gear version of the aircraft was completed and flying, while a tricycle gear version was under construction.

Specifications (AC-11)

References

External links

* {{Coelho aircraft AC-11 1990s Brazilian sport aircraft 1990s Brazilian ultralight aircraft 1990s Brazilian civil utility aircraft Single-engined tractor aircraft Low-wing aircraft Homebuilt aircraft