The Y-12 is a modern, high-winged twin-turboprop-powered utility aircraft designed, developed, and manufactured by the local concern of Harbin Aircraft Industry Group of China. First flown on July 14th, 1982, the aircraft has been in constant production since service entry occurred in 1985. The type serves a myriad of operators on several continents, these customers ranging from Cambodia and Djibouti to Uganda and Zambia (though its primary user remains China). Its versatile design is such that the aircraft can serve at the military, government, and civilian levels.
The high-wing arrangement provides for excellent lift and drag properties, giving the Y-12 equally-excellent short-field / rough-field capabilities. The mainplanes are braced by thick struts emanating from the lower sides of the fuselage. The cockpit carries its crew of two in a side-by-side seating arrangement with good views had over the short nosecone. The fuselage is slab-sided to better serve internal volume and the empennage raises as it tapers to the rear. Rectangular windows run along the sides of the fuselage. The tail unit is completed by a single, clipped vertical fin and low-set horizontal planes. The undercarriage of the Y-12, of three-wheeled design, is fixed for simplicity and ruggedness.
Origins of the Y-12 are based in the earlier Y-11, an aircraft also developed by Harbin, and this product was another twin-engined, high-winged performer of similar form and function (though only about 50 were produced). The goal of the new program was to expound upon the stronger qualities of the earlier Y-11 so improvements were instituted throughout the design. Dimensions increased and all-new mainplane members were forged as the project moved along during the early 1980s. A single prototype was used to prove the Y-12 design sound.
Once approved, the Y-12 entered production with thirty early-form aircraft designated as "Y-12 (I)". These carried a pair of American-Canadian Pratt & Whitney Canada (PWC) PT6A-11 turboprops of 500 horsepower each. More improvements followed (including the introduction of uprated PWC PT6A-27 engines), once in service, to produce the "Y-12 (II)" designation. The series was then officially certified for Chinese airspace in 1985.
The "Y-12 (III)" was in the works with the indigenous WJ-9 turboprop to power it and this mark eventually became the Y-12C in service. The 19-seat "Y-12 (IV)", certified around 1995, became an improved model with increased wingspan and modified wingtips.
The Y-12D serves the Chinese Army in the parachute training role and sports four-bladed propeller units. The Y-12E, certified around 2006, has seating for 18 and is driven by 2 x PWC PT6A-135A engines with four-bladed propellers.
The Y-12F is a heavily-modified variant featuring all-new wing mainplanes, larger fuselage, more powerful engines (PWC PT6A-65B), and a wholly-retractable wheeled undercarriage. Performance of this model is improved over earlier marks. A first-flight of this aircraft was recorded in December of 2010 and the type was certified before the end of 2015. The Y-12G is its proposed cargo-minded variant.