RIDA ALEKS-251

TYPE: Six-seat amphibian.

PROGRAMME: Announced 2003, when first flight planned in second half of 2004; this, apparently, did not take place and the programme remained unfruitful, but still active, in early 2006. Reportedly developed for an undisclosed Russian Federation ministry, which has a requirement for up to 800.

DESIGN FEATURES: Parasol wing amphibian with single-step hull; cruciform empennage with sweptback fin. Constant-chord wing and tailplane; outrigger floats retract to form wingtips when not in use. Operable on water with wave height of 0.45 m (1 ft 6 in).

FLYING CONTROLS: Conventional and manual. Horn-balanced rudder. Flaps.

LANDING GEAR: Optional tricycle type.

POWER PLANT: Two LOM M332S four-cylinder engines, each 127 kW (170 hp), projecting forward from undersides of wing. Fuel tanks in wings; total capacity 800 litres (211 US gallons, 176 Imp gallons).

ACCOMMODATION: Pilot and five passengers; six passengers at maximum capacity. Port, centre transparency removable for access to cabin; windscreen split along centreline and hinged at base, both sides, to ease access for pilot(s).

EQUIPMENT: MVEN ballistic recovery parachute.

DIMENSIONS, EXTERNAL:

  • Wing span: 13.20 m (43 ft 3¾ in)
  • Wing chord, constant: 1.50 m (4 ft 11 in)
  • Wing aspect ratio: 8.8
  • Length overall: 10.54 m (34 ft 7 in)
  • Height, wheels retracted: 3.10 m (10 ft 2 in)
  • Tailplane span: 4.15 m (13 ft 7½ in)
  • Wheel track (optional): 2.35 m (7 ft 8½ in)
  • Wheelbase (optional): 6.25 m (20 ft 6 in)
  • Propeller diameter: 1.855 m (6 ft 1 in)
  • Distance between propeller centres: 3.00 m (9 ft 10 in)

DIMENSIONS, INTERNAL:

  • Cabin: Length: 3.10 m (10 ft 2 in)
    • Max width: 1.40 m (4 ft 7 in)
    • Max height: 1.30 m (4 ft 3¼ in)

AREAS:

  • Wings, gross: 19.80 m² (21.31 sq ft)

WEIGHTS AND LOADINGS:

  • Weight empty: 1,360 kg (2,998 lb)
  • Max payload: 600 kg (1,323 lb)
  • Max T-O weight: 2,100 kg (4,629 lb)
  • Max wing loading: 106.1 kg/m² (21.72 lb/sq ft)
  • Max power loading: 8.29 kg/kW (13.61 lb/hp)

PERPORMANCE:

  • Max level speed: 127 kt (235 km/h; 146 mph)
  • Normal cruising speed at FL98: 113 kt (210 km/h; 130 mph)
  • Econ cruising speed at FL98: 97 kt (180 km/h; 112 mph)
  • Unstick speed: 59 kt (110 km/h; 68 mph)
  • Stalling speed: clean: 62 kt (114 km/h; 71 mph)
    • flaps and gear down: 52 kt (96 km/h; 60 mph)
  • Max rate of climb at S/L: 300 m (984 ft)/min
  • T-O run: land: 300 m (985 ft)
    • water: 470 m (1,545 m)
  • Landing run: land: 300 m (985 ft)
    • water: 280 m (920 m)
  • Range with 500 kg (1,102 lb) payload:
    • at normal cruising speed: 399 n miles (1,740 km; 459 miles)
    • at econ cruising speed: 1,512 n miles (950 km; 590 miles)
    • ferry: 1,943 n miles (3,000 km; 2,236 miles)
  • Endurance: 20 h

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

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