The Cranfield A1 Eagle is a British single-seater aerobatics monoplane, powered by a flat-six engine. Two seats can be fitted for training purposes. Only one was built.

Design and development

The A1 is a low-wing cantilever monoplane. The wing has straight edges, with sweep only on the leading edge, and squared tips. It is a single piece structure of light alloy construction, with Frise type mass balanced ailerons which are fabric covered aft of the spar; a ground adjustable trim tab is fitted on the port side. There are no flaps. The empennage is also straight tapered and of similar construction to the wing, though the rudder is fabric covered. There is a small dorsal fin. All rear control surfaces are

horn balanced Horn most often refers to: * Horn (acoustic), a conical or bell shaped aperture used to guide sound ** Horn (instrument), collective name for tube-shaped wind musical instruments * Horn (anatomy), a pointed, bony projection on the head of various ...

; the tailplane's incidence can be adjusted on the ground and the

starboard Port and starboard are nautical terms for watercraft and aircraft, referring respectively to the left and right sides of the vessel, when aboard and facing the bow (front). Vessels with bilateral symmetry have left and right halves which are ...

elevator has a ground adjustable trim tab. The fuselage is a mostly fabric covered welded tube structure with wooden

former A former is an object, such as a template, gauge or cutting die, which is used to form something such as a boat's hull. Typically, a former gives shape to a structure that may have complex curvature. A former may become an integral part of the ...

s, though the upper decking is

plywood Plywood is a material manufactured from thin layers or "plies" of wood veneer that are glued together with adjacent layers having their wood grain rotated up to 90 degrees to one another. It is an engineered wood from the family of manufactured ...

. The

cockpit A cockpit or flight deck is the area, usually near the front of an aircraft or spacecraft, from which a Pilot in command, pilot controls the aircraft. The cockpit of an aircraft contains flight instruments on an instrument panel, and the ...

has a side hinged bubble canopy. Normally flown as a single seater, a second seat can be added for training. The fixed, conventional undercarriage is from a de Havilland Chipmunk, with hydraulic brakes in the wheels. The A1's construction was delayed by funding problems: though design work began in 1968, the first flight was not made until 1976. By mid-1977 some 40 hours had been flown under the power of a 156 kW (210 hp)

Rolls-Royce Continental IO-360-D The Continental IO-360 is a family of fuel-injected air-cooled, horizontally opposed six-cylinder aircraft engines manufactured by Continental Motors in the United States of America, now part of AVIC International since 2010. The engine is ...

. This was then replaced with a 209 kW (280 hp) Lycoming IO-540-D (Special) driving a three blade

propeller A propeller (colloquially 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 ...

which markedly improved the performance. Revised ailerons were fitted, the rudder horn balanced and heightened. Only one aircraft (''G-BCIT'') was built and this remains in store at Cranfield in 2010.

Specifications (Mk 2)

References

{{reflist, refs= {{cite book , title= Jane's All the World's Aircraft 1976-77, last= Taylor , first= John W R , year=1976, publisher=Jane's Yearbooks , location= London, isbn=0-354-00538-3 , pages=816–7 {{cite book , title= Jane's All the World's Aircraft 1979-1980, last= Taylor, first= John W. R. , year=1979, publisher= Jane's Publishing Co., location= London, pages=240 {{cite book , title= Wrecks & Relics, last=Ellis, first=Ken, year=2010, edition=22, publisher=Crecy , location=Manchester , isbn=978-0-85979-150-2, page=8 1970s British sport aircraft Aerobatic aircraft Low-wing aircraft Single-engined tractor aircraft Aircraft first flown in 1976