English name: Turbo-Raven

TYPE: Agricultural sprayer.

PROGRAMME: Original piston-engined PZL-106 designed early 1972; first flight (SP-PAS), with IO-720 engine, 17 April 1973; last piston-engined aircraft built in 1990. First flight of turboprop-powered prototype (SP-PAA) 18 September 1985; FAR Pt 23 certification early 1994; features include taller fin and increased payload. A Turbo-Kruk was flown experimentally in 1997 with a 559 kW (750 shp) P&WC PT6A-34AG turboprop, modified cockpit and minor aerodynamic improvements.

CURRENT VERSIONS: PZL-106BT-601: Standard production version with Walter M 601D engine.
PZL-106BTU-34: Export version with PT6A-34AG turboprop; first flight (SP-PBW, 262nd Kruk built) 19 August 1998. Redesigned engine cowling, improved electrical system and new instrument panel. Aimed initially at Latin American market.
Following description applies to current production PZL-106BT-601 except where indicated.

CUSTOMERS: Total of 39 built by mid-2000, including one BT-34 in 1998 and two BT-601s in 1999. Export deliveries include Argentina (21) , Egypt, Iran, South Africa (five) and Sudan. Overall total of 270 (all versions) built up to mid-2002, comprising eight prototypes, 143 PZL-106As (of which two converted to -106B) between 1975 and 1981, 79 PZL-106BR/BSs and 42 PZL-106BTs. No known production in 2000, 2001 or 2002, although promotion continued in 2003.

DESIGN FEATURES: Typical low-, braced-wing agricultural monoplane with hopper at CG and high cockpit with good forward view.
Wings have upward-cambered tips; braced tailplane. Sweepback 6° at quarter-chord; dihedral 6°; incidence 6°.

FLYING CONTROLS: Conventional and manual. Slotted ailerons (each with electrically actuated trim tab); mass-balanced elevators (with port trim tab); rudder has trim tab and anti-servo tab. Full-span, four-segment slats on each wing leading-edge; trailing-edge flaps.

STRUCTURE: Duralumin wings with metal and polyester fabric covering and GFRP tips; flaps and ailerons of duralumin with polyester fabric skins; GFRP/foam core sandwich slats; duralumin V bracing struts. Welded steel tube fuselage, with polyurethane enamel coating and quickly removable light alloy and GFRP panels; structure can be pressure tested for cracks. Duralumin tail unit has metal-skinned fixed surfaces and polyester fabric-covered control surfaces. Structure corrosion resistant, and additionally protected by external finish of polyurethane enamel.

LANDING GEAR: Non-retractable tailwheel type, with oleo-pneumatic shock-absorber in each unit. Mainwheels, with low-pressure tyres, are each carried on a side V and half-axle. Steerable tailwheel has tubeless tyre. Pneumatically operated mainwheel hydraulic disc brakes; parking brake.

POWER PLANT: PZL-106BT-601: One 548 kW (735 shp) Walter M 601D-1 turboprop; Avia V 508 D three-blade propeller.
PZL-106BTU-34: One 559 kW (750 shp) Pratt & Whitney Canada PT6A-34AG turboprop and Hartzell HC-B3TN-3D three-blade propeller.
Fuel in two integral wing tanks, total capacity 560 litres (148 US gallons; 123 Imp gallons); can be increased to total of 950 litres (251 US gallons; 209 Imp gallons) by using hopper as auxiliary fuel tank. Gravity refuelling point on each wing; semi-pressurised refuelling point on starboard side of fuselage.

ACCOMMODATION: Single vertically adjustable seat in enclosed, ventilated and heated cockpit with steel tube overturn structure. Provision for instructor's cockpit with basic dual controls, forward of main cockpit and offset to starboard, for training of pilots in agricultural duties. Optional rearward-facing second seat (for mechanic) to rear. Jettisonable window/door on each side of cabin. Pilot's seat and seat belt designed to resist 40 g impact. Cockpit air conditioning optional.

AVIONICS: Comms: VHF com transceiver standard; 720-channel UHF transceiver optional.

EQUIPMENT: Easily removable non-corroding (GFRP) hopper/tank, forward of cockpit, can carry 1,500 kg (3,307 lb) of dry or liquid chemical, and has maximum capacity of 1,500 litres (396 US gallons; 330 Imp gallons).
Turnaround time, with full load of chemical, is approximately 28 seconds. Hopper quick-dump system can release 1,000 kg of chemical in 5 seconds or less. Pneumatically operated intake for loading dry chemicals optional. Distribution system for liquid chemical (jets or atomisers) powered by fan-driven centrifugal pump. Tunnel spreader, with positive on/off action for dry chemicals. For ferry purposes, hopper can be used to carry additional fuel instead of chemical.
When converted into two-seat trainer (see Accommodation), standard hopper can be replaced easily by container with reduced capacity tank for liquid chemical. Steel cable cutter on windscreen and each mainwheel leg; steel deflector cable runs from top of windscreen cable cutter to tip of fin. Windscreen washer and wiper standard. Other equipment includes clock, rearview mirror, second (mechanic's) seat (optional), landing light, anti-collision light, and night working lights (optional).