TYPE: Four-seat amphibian/kitbuilt.

PROGRAMME: Prototype (ZK-SFA), designed by Bill Townson and built by Seaflight (NZ) Ltd, first flew 28 September 2001; re-registered ZK-TNZ in May 2005; had flown some 30 hours by July 2005, when displayed at AirVenture, Oshkosh. First kits then due for delivery in second quarter of 2006. However, design considerably revised in late 2005 under aeronautical engineer Richard Roake, reducing drag and improving performance, delaying completion of first production aircraft to late 2006/early 2007.

CUSTOMERS: Four kits sold in New Zealand before international launch.

COSTS: Kit USD90,000 less engine and avionics (2006).

DESIGN FEATURES: Mid-wing amphibian with moderate wing leading-edge sweepback. Integral wingtip floats of prototype replaced by tip winglets, with narrow floats repositioned inboard at approx three-fifths of span. Prototype also had two-step hull with ducted steps for cleaner unstick from water; air supplied from intake in mainwheel bays; this replaced by unstepped bottom incorporating forward-hinged, plank-shape hydroski which supports full MTOW at 18 knots (33 km/h; 21 mph). Dished upper fuselage with water drain hole, allowing lower thrust line for pusher propeller, which has 2.5 cm (1 in) fuselage clearance. Sweptback V tail. Leading-edge root extension to wing added after early trials. Kitbuilt to 51 per cent rule, but certifiable to FAR/EASA 23.

FLYING CONTROLS: Manual. Twin ruddervators, each with horn balance and flight-adjustable trim tab. Slotted flaps. Actuation by carbon fibre pushrods.

STRUCTURE: Composites throughout. Glass fibre hull, except carbon fibre upper section. Carbon fibre wing. Stainless steel metal fittings.

LANDING GEAR: Tricycle type; retractable. Electric actuation. Nosewheel retracts forward; mainwheels inward to underside of wing. Main tyres 6.00-6; nosewheel 5.00-5. Retractable water rudder behind second step. Simplified gear (omitting forward strut) to be introduced on production aircraft.

POWER PLANT: Prototype with one 157 kW (210 hp) Franklin flat-four, driving an MT-Propeller MT-18-D/LD-183-119 three-blade, variable-pitch pusher propeller. Production aircraft to have 190 kW (255 hp) Innodyn 255TE turboprop with five-blade propeller. Fuel in two wing tanks, combined capacity 104 litres (27.5 US gallons; 22.9 Imp gallons). Alternative power plants in 157 to 186 kW (210 to 250 hp) range. Optional ferry tanks in outer wings; max fuel capacity 520 litres (137 US gallons; 114 Imp gallons), although 455 litres (120 US gallons; 100 Imp gallons) for production version.

ACCOMMODATION: Four persons in two forward-facing pairs. Fixed windscreen, plus upward- hinged door each sides. Baggage compartment in nose accessed by external door atop fuselage.

DIMENSIONS, EXTERNAL:

• Wing span: 10.36 m (34 ft 0 in)
• Wing aspect ratio: 8.0
• Length overall: 7.87 m (25 ft 10 in)
• Height overall: 2.08 m (6 ft 10 in)
• Propeller diameter: 1.83 m (6 ft 0 in)

DIMENSIONS, INTERNAL:

• Cockpit: Length: 2.39 m (7 ft 10 in)
• Max width: 1.35 m (4 ft 5 in)
• Baggage compartment volume: 1.0 m³ (35 cu ft)

AREAS:

• Wings, gross: 13.38 m² (144.0 sq ft)
• Tail surfaces: 2.42 m² (26.0 sq ft)

WEIGHTS AND LOADINGS:

• Weight empty: 825 kg (1,819 lb)
• Max T-O weight: 1,500 kg (3,306 lb)
• Max wing loading: 112.1 kg/m² (22.96 lb/sq ft)
• Max power loading: 7.89 kg/kW (12.96 lb/hp)

PERFORMANCE:

• Cruising speed: 165 kt (306 km/h; 190 mph)
• Stalling speed, flaps down: 55 kt (102 km/h; 64 mph)

The article appears in the following publication:
Jane's All the World's Aircraft 2007-2008. Jane's Information Group Ltd. 2007. ISBN: 0-7106-2792-0