TYPE: Light utility turboprop.

PROGRAMME: Designed by Aeronautical Engineers Australia (AEA), beginning in 1993, with assistance from US aerodynamicist John Roncz; company renamed Explorer Aircraft Corporation. Proof-of-concept (POC) prototype (VH-OKA), designated Explorer 350R, made first flight 23 January 1998 and had flown more than 70 hours up to award of Development C of A on 27 April 1998. Prototype (re-registered VH-ONA in May 1998) and given Experimental C of A on 27 April 1999; IFR certification 6 May 1999; departed for USA 20 May 1999.
Re-engined with 447 kW (600 shp) Pratt & Whitney Canada PT6-135B turboprop as prototype Explorer 500T, in which form it first flew on 9 June 2000; simultaneously fitted with six-screen EFIS; public debut at EAA AirVenture Oshkosh in August 2000; had flown 500 hours in all configurations by mid-2003. Additional funding being sought in mid-2003 to pursue certification, which would be achieved some 30 months after funding in place, with first deliveries in 2007, allowing for 2003 launch.

CURRENT VERSIONS: 350R: Proof-of-concept prototype, powered by one 261 kW (350 hp) Teledyne Continental TSIO-55-E3B piston engine. Not to be marketed.
500T: Initial production version employing airframe similar to that of 350R but with 447kW (600 shp) Pratt & Whitney Canada PT6-135B turboprop. As described.
500R: To have been offered with airframe, payload and performance as for 500T, but with 447 kW (600 hp) Orenda OE600 liquid-cooled V-8 piston engine. However, this power plant has been withdrawn from the market.
750T: Stretched version with plugs fore and aft of wing; up to 16 passengers; PT6A-60A engine flat rated to 597 kW (800 shp).

COSTS: 500T US$1.035 million; 750T US$1.16 million (2000).

DESIGN FEATURES: High-mounted, strut-braced wing with Roncz advanced aerofoil profile and constant chord, thick centre-section; outer panels (approximately 40 per cent of each half-span) sharply tapered; tall, sweptback fin and rudder. Constant cross-section cabin. 'Productionisation' to be accelerated by use of state-of-the-art computer modeling.
Wing thickness/chord ratio 19.6; washout 2°.

FLYING CONTROLS: Conventional and manual. Fowler flaps with three settings for take-off, approach and landing, plus neutral; three-axis trim via cable/screw-jack actuated tabs in starboard elevator, starboard aileron and rudder.

STRUCTURE: Carbon fibre shell over metal frame; remainder of primary structure is of high-grade aluminium alloy, with composites flaps, elevators, ailerons and rudder.

LANDING GEAR: Fully retractable tricycle type, with single wheel on each unit. Mainwheel tyre size 22x7.75-10, nosewheel 6.00-6. Steerable nose oleo unit retracts rearward; glass fibre mainwheel legs retract by first extending downward and then crossing over and upward so that port wheel is housed in streamline fairing on starboard side, and vice versa. Mainwheels do not intrude into cabin. Hydraulic brakes. Structural provision for optional floats.

POWER PLANT: 500T: One Pratt & Whitney Canada PT6-135B turboprop, flat rated at 447 kW (600 shp), driving a four-blade, constant-speed, fully reversing Hartzell D9511FK-2 propeller. Fuel tanks in wing centre-section, total capacity 1,049 litres (277 US gallons; 231 Imp gallons).
750T: One Pratt & Whitney Canada PT6A-60A turboprop, flat rated at 597 kW (800 shp), driving a four-blade constant-speed Hartzell reversing propeller. Fuel capacity 1,514 litres (400 US gallons; 333 Imp gallons).
All versions have refuelling port on top of each wing.

ACCOMMODATION: 500T: 10 seats, including pilot(s); 750T: 16 seats, including pilot(s). Forward-opening crew door on each side of forward fuselage. Large cargo door at rear of cabin on port side. Cabin is extensively glazed with five (500T) or seven (750T) large, square windows on each side. Fuselage hardpoints for tiedowns and cargo nets. Air conditioning standard.

SYSTEMS: 28 V DC electrical system. Engine-driven hydraulic pump. De-icing system, comprising leading-edge boots and heated propeller.

AVIONICS: Comms: Dual Garmin GNS 430 GPS/com/nav; GTX 327 transponder; GMA 340 audio panel.
Flight: Garmin GI 106A VOR/LOC/GS; Meggitt System 55 programmer/computer; remote annunciator; altitude selector/alerter; 6446 fluxgate; Meggitt autopilot.
Instrumentation: Dual Meggitt Avionics 84-132-1 EDU; 84-133-1 PFD; 84-134-1 ND.