HAMC Y-12 (II)

Chinese name: Yunshuji-12 (II) (Transport aircraft 12)

Twin-turboprop STOL general purpose transport.

PROGRAMME:

Initiated as uprated version of Y-12 (I) (1987-88 and earlier Jane's); first flight 16 August 1984; domestic certification 25 December 1985; UK (BCAR Section K) certification received 20 June 1990; FAA type approval of Y-12 (IV) received 26 March 1995 and production approval September 1995.

CURRENT VERSIONS: Y-12 (I):

Initial version (first flight 14 July 1982), with PT6A-11 engines; three prototypes and approximately 30 production examples built; described in 1987-88 Jane's. Y-12 (II): Current production version; higher rated engines, no leading-edge slats and smaller ventral fin. Detailed description applies to this version except where indicated. Y-12 (IV): Improved version (first flight 30 August 1993). Modifications to wingtips, control surface actuation, main gear and brakes; redesigned seating for 18 to 19 passengers; starboard side rear baggage door; maximum payload and maximum T-O weight increased. Further changes include Collins or Bendix/King com/nav for both VFR and IFR, plus optional colour weather radar, GPS, Omega navigation, wing and tail de-icing, and oxygen system. Domestic certification received 3 July 1994 and FAA approval to FAR Pt 23 on 26 March 1995. Future versions: Plans under consideration include stretched version and one with pressurised cabin.

STATUS: Pakistan posseses 1 aircraft of this type which was kept after a Afhnistani crew fled to pakistan during Afghan war in mid 80's.

DESIGN FEATURES: Designed to standards of FAR Pts 23 and 135 Appendix A and developed to improve upon modest payload/range of original piston-engined Y-11. Constant chord high braced wings, with small stub-wings at cabin floor level supporting mainwheel units; basically rectangular-section fuselage, upswept at rear; non-swept tail surfaces; large dorsal fin; ventral fin under tailcone. Wing section LS(1)-0417; thickness/chord ratio 17 per cent; dihedral 1° 41'; incidence 4°.

FLYING CONTROLS: Drooping ailerons, horn balanced elevators and rudder, all mechanically actuated; trim tab in starboard aileron, rudder and each elevator; electrically actuated two-segment double-slotted flaps on each wing trailing-edge.

STRUCTURE: Conventional all-metal structure with two-spar fail-safe wings and stressed skin fuselage; Ziqiang-2 resin bonding on 70 per cent of wing structure and 40 per cent of fuselage; integral fuel tankage in wing spar box; bracing strut from each stub-wing out to approximately one-third span.

LANDING GEAR: Non-retractable tricycle type, with oleo-pneumatic shock-absorber in each unit. Single-wheel main units, attached to underside of stub-wings. Single non-steerable nosewheel. Mainwheel tyres size 640 x 230 mm, pressure 5.50 bars (80 lb/sq in); nosewheel tyre size 480 x 200 mm, pressure 3.50 bars (51 lb/sq in). Hydraulic brakes. Minimum ground turning radius 16.75 m (54 ft 11{1/2} in).

POWER PLANT: Two Pratt & Whitney Canada PT6A-27 turboprops, each derated to 462 kW (620 shp) and driving a Hartzell HC-B3TN-3B/T10173B-3 three-blade constant-speed reversible-pitch propeller. All fuel in tanks in wing spar box, total capacity 1,616 litres (427 US gallons; 355.5 Imp gallons), with overwing gravity filling point each side. Domestic WJ9 turboprop (442 to 520 kW; 593 to 697 shp) under development for Y-12 and other aircraft.

ACCOMMODATION: Crew of two on flight deck, with access via forward-opening door on port side. Four-way adjustable crew seats. Dual controls. Main cabin can accommodate up to 17 passengers in commuter configuration, in three-abreast layout (with aisle), at seat pitch of 75 cm (30 in). Alternative layouts for up to 15 parachutists, or all-cargo configuration with 11 tiedown rings. Passenger/cargo double door on port side at rear, rear half of which opens outward and forward half inward; foldout steps in passenger entrance. Emergency exits on each side at front of cabin and opposite passenger door on starboard side at rear. Baggage compartments in nose and at rear of passenger cabin, for 100 kg (220 lb) and 260 kg (573 lb) respectively.

SYSTEMS: Hamilton Standard R70-3WG environmental control system. Hydraulic system (operating pressure 118 to 147 bars; 1,711 to 2,132 lb/sq in) for mainwheel brakes. Two 6 kW DC starter/generators, two 600 VA 400 Hz single-phase static inverters and one 43 Ah Ni/Cd battery for electrical power. Goodrich Type 29S-7D 5178 anti-icing system optional for wing, tailplane and fin leading-edges.

AVIONICS: Comms: VHF-251 and HF-230 radio, AUD-251A intercom and TDR-950 transponder.
Radar: Bendix/King 1400C, RDS-81 or RDS-82 weather radar.
Flight: ALT-50 radio altimeter, DME-451, ADF-650A, MKR-350 marker beacon receiver, VIR-351 VOR, GLS-350 glide slope receiver and PN-101 pictorial display. Doppler navigation with satellite responder optional (for example, in mineral detection role). Instrumentation: 20025-11324 airspeed indicator, 510-8D10 horizon, 101420-11934 encoding altimeter, 30230-11101 vertical speed indicator, 9551-BN541 bank indicator, LC-2 magnetic compass, ZWH-1 outside air temperature indicator, and ZEY-1 flap position indicator; dual engine torquemeters, interturbine temperature indicators, gas generator tachometers, oil temperature and pressure indicators, fuel pressure and quantity indicators; 309W clock; and XDH-10B warning light box.

EQUIPMENT: Hopper for 1,200 litres (317 US gallons; 264 Imp gallons) of dry or liquid chemical in agricultural version. Appropriate specialised equipment for firefighting, geophysical survey (for example, long, kinked sensor tailboom) and other missions.

LENGTH (m) : 14.86
HEIGHT (m) : 5.67
WING SPAN (m) : 17.23
MAX T-O WEIGHT (kg) : 5300
MAX WING LOAD (kg/m{2}) : 145.90
MAX LEVEL SPEED (knots) : 157
MAX RANGE (nm) : 723
SERVICE CEILING (m) : 7000
T-O RUN (m) : 340
LANDING RUN (m) : 200.0
MAX RATE CLIMB (m/min) : 486