TYPE: Aerobatic single-seat sportplane; aerobatic two-seat sportplane.

PROGRAMME: Initial version was Zivko Edge 360. Design work on 540 began in 1992 with first flight in 1993; 540T followed in 1999 with first flight 2000.

CURRENT VERSIONS: 540: Single-seat version.
540A: Improved version introduced at Sun 'n' Fun, April 2001 (N24KC); has larger rudder and elevator for improved handling. 540AK version may have IO-540-K engine.
540T: Two-seat model introduced March 2000; two are TK versions.

CUSTOMERS: Totals of 23 540s and seven 540Ts built by end of 2003, including examples to Mexico, South Africa, Switzerland and Australia. Three 540Ts registered in 2003; no 540/As.

COSTS: Programme cost US$1.1 million by 2003. Edge 540 US$231,655; Edge 540T US$245,632 (2003).

DESIGN FEATURES: Optimised for aerobatics; customised John Roncz aerodynamic design; rate of roll 420°/s. Mid-positioned, tapered wing with straight leading-edge and large, horn-balanced ailerons and unique aerofoil. Transparencies in lower sides and floor of cockpit.

FLYING CONTROLS: Conventional and manual. Ailerons and elevator actuated by pushrods; horn-balanced rudder by cables. Flight adjustable tabs in port elevator. Suspended, spade-type tab on each aileron; electric trim.

STRUCTURE: 4130 Steel tube fuselage; upper fuselage and fairings of composites; lower aft fuselage fabric covered, stressed to ultimate ±15g; all-composites fully cantilevered two-spar wing. Fully composites empennage with no wire bracing.

LANDING GEAR: Tailwheel type; fixed. Main legs aluminium sprung steel; Cleveland 5.00-5 wheels and hydraulic brakes; optional speed fairings. Tyre pressure 3.45 bar (50.0 lb/sq in). Spring steel tail gear, with chrome-plated, solid 4.00-4 tailwheel, choice of fixed or steerable.

POWER PLANT: One Textron Lycoming IO-540 modified to produce 254 kW (340 hp), driving Hartzell HC-C3YR-4AX or optional Hartzell HC-C3YR-1AX1 three-blade, composites propeller. Edge 540 has single 72 litre (19.0 US gallon; 15.8 Imp gallon) forward fuselage fuel tank, plus optional total of 159 litres (42.0 US gallons; 35.0 Imp gallons) in wing tanks; Edge 540T has single 76 litre (20.0 US gallon; 16.6 Imp gallon) fuselage tank and two optional 83 litre (22.0 US gallon; 18.3 Imp gallon) wing tanks. Oil capacity 11.4 litres (3.0 US gallons; 2.5 Imp gallons). Inverted oil (Christen) and fuel (ZAI) systems.

ACCOMMODATION: Pilot (pilot and passenger in tandem in 540T) under one-piece perspex canopy hinged on starboard side; carbon fibre contoured seats. Baggage compartment forward of front seat.

SYSTEMS: 12 V DC system with light weight B&C 8A alternator and regulator. Bendix fuel injection system.

AVIONICS: Comms: Becker com and Mode C transponder.
Flight: Optional Sierra Flight Systems EFIS.