TYPE: Single-seat ultralight/kitbuilt.

PROGRAMME: Prototype B-612 (OK-GUZ 02), designed and built by Ing Marek Ivanov; first flight in or by October 2001. Established FAI subclass RAL1 speed record of 104.9 kt (194.2 km/h; 120.7 mph) on 11 October 2003, then powered by a 29.5 kW (39.6 hp) Rotax 447 two-cylinder, in-line piston engine. Production version has wider (0.70 m; 2 ft 3½ in) cockpit.

COSTS: EUR25,845 with HKS engine, EUR22,100 with Rotax engine; kit, less engine and instruments EUR16,300; all plus tax (2006).

DESIGN FEATURES: Low-mounted, constant-chord wing; low-mounted, cantilever tailplane; sweptback fin. Wings removable for storage.

FLYING CONTROLS: Conventional and manual. No aerodynamic balances. Split flaps.

STRUCTURE: Welded 4130 chromoly steel fuselage with Ceconite fabric covering; composites empennage in current versions. Epoxy composites wing with carbon fibre main spar.

LANDING GEAR: Tricycle type; retractable. Mainwheels on welded steel legs, with hydraulic shock absorbers, retract outwards by manual hydraulic pump; wheel extremities protrude below wing lower surface when retracted. Steerable nosewheel. Mainwheel brakes.

POWER PLANT: One piston engine: 44.7 kW (60 hp) HKS 700E or 36.8 kW (49.3 hp) Rotax 503 driving a two-blade Sportprop propeller. Fuel capacity 30 litres (7.9 US gallons; 6.6 Imp gallons) in composites tank at rear of engine firewall or, optionally, in two wing tanks with combined capacity of 50 litres (13.2 US gallons; 11.0 Imp gallons).

EQUIPMENT: Optional ballistic recovery parachute.

DIMENSIONS, EXTERNAL:

  • Wing span: 6.85 m (22 ft 5¾ in)
  • Length overall: 4.80 m (15 ft 9 in)
  • Height overall: 1.76 m (5 ft 9¼ in)

DIMENSIONS, INTERNAL:

  • Cockpit max width: 0.60 m (1 ft 11¾ in)

AREAS:

  • Wings, gross: 6.85 m² (73.7 sq ft)

WEIGHTS AND LOADINGS:

  • Weight empty: 175 kg (386 lb)
  • Max T-O weight: 300 kg (661 lb)

PERFORMANCE (HKS engine and wing tanks):

  • Never-exceed speed (VNE): 145 kt (270 km/h; 167 mph)
  • Normal cruising speed: 108 kt (200 km/h; 124 mph)
  • Stalling speed: 36 kt (65 km/h; 41 mph)
  • T-O run: 50 m (165 ft)
  • T-O to 15 m (50 ft): 130 m (430 ft)
  • Landing from 15 m (50 ft): 120 m (395 ft)
  • Max rate of climb at S/L: 360 m (1,181 ft)/min
  • Max range: 486 n miles (900 km; 559 miles)
  • g limits: +4/-2