TYPE: Tandem-seat kitbuilt.
PROGRAMME: Prototype first flew November 1985; in production from 1986.
CURRENT VERSIONS: S-7: Original kitbuilt version, superseded by S-7S.
S-7C: Factory-built version; changes include additional fuselage side stringers, smaller ailerons, larger flaps, taller (15 cm; 6 in) fin and rudder, extended dorsal strake, control surface gap seals, improved low-friction control cable runs, tab for pitch trim, tappered spring steel main landing gear legs with improved fairings, dual calliper brakes, larger baggage compartment and corrosion-proofing as standard. First flight (N11632; second airframe) 20 December 1996. Further aircraft, N2506A for trials, built 2000. Type certificate awarded 14 September 2001, permitting start to deliveries; however, deliveries were on hold during 2003, pending definitive Sport Pilot regulations.
S-7S: Kitbuilt version of S-7C, as described. Kit conforms to FAA 51 per cent rule.
CUSTOMERS: Total of 344 5-7 kits sold, of which 190 completed by October 2003. Ten S-7C built for stock by this date.
COSTS: S-7 kit, with engine: Rotax 912UL, US$27,745; Rotax 912ULS, US$29,550; S-7S kit with Rotax 912ULS, US$34,180 (2003). Production version cost US$55,000 for first 50 examples.
DESIGN FEATURES: High-wing, mid-tailplane configuration with sweptback fin, constant-chord wings and tapered tailplane. Wings braced by A-struts; empennage mutually wire-braced. Wings fold rearwards and tailplanes upwards for stowage; usual rigging/de-rigging time 30 to 45 minutes. Quoted build time for kit version is 500 to 700 hours.
NACA 2412 wing section, thickness/chord ratio 14 per cent; dihedral 1°; twist 25°.
FLYING CONTROLS: Conventional and manual. Cable-operated rudder and ailerons, the last-named spade-assisted, and torque tube-operated elevators; trim tab on starboard elevator; cable-operated four-position flaps (0, 8, 16 and 26°).
STRUCTURE: Wings have two tubular 6061-T6 alloy spars, preformed aluminium tube ribs riveted and clipped to spars and sheet alloy leading-edges; fuselage and tail surfaces of welded 4130 steel; glass fibre forward decking and engine cowling. Airframe is fabric-covered.
LANDING GEAR: Non-retractable tailwheel type with tubular spring steel main legs; steerable, full-swivelling tailwheel; mainwheel size 16x5 (6.00-6 on S-7C), maximum pressure 2.41 bar (35 lb/sq in); tailwheel with solid tyre, size 8x2; Matco/Cleveland wheels with hydraulic brakes. Optional speed fairings on main legs increase cruising speed by 2 to 4 kt (5 to 8 km/h; 3 to 5 mph). Tundra tyres, skis, floats and Stoddart-Hamilton Aerocet amphibious floats optional.
POWER PLANT: One 59.6 kW (79,9 hp) Rotax 912 UL or one 73.5 kW (98.6 hp) Rotax 912 ULS four-cylinder piston engine, each with 2.27:1 reduction gear, driving a two-blade, ground-adjustable propeller (Tennessee on 912 UL and Sensenich on 912 ULS). S-7C and S-7S have Rotax 912 ULS with 2.43:1 reduction gear; driving Sensenich two-blade propeller. Fuel contained in two wing tanks, combined capacity 68 litres (18.0 US gallons; 15.0 Imp gallons), of which 58 litres (15.2 US gallons; 12.7 Imp gallons) are usable. Oil capacity 2.9 litres (0.75 US gallon; 0.6 Imp gallon).
ACCOMMODATION: Pilot and passenger in tandem on fore- and aft-adjustable seats; lap and shoulder harness standard; optional deluxe seats. Dual controls standard. Cabin is heated and ventilated. Upward-hinged door on each side is flight-openable with uplocks; quick-release hinge pins optional. Baggage compartment at rear of cabin.
AVIONICS: To customer's choice; optional GPS, VHF com and intercom on S-7C.