Staff Writer (Updated: 7/14/2016):
Its design is attributed to Xian's "603 First Aircraft Design Institute" (part of AVIC).
To date, the Chinese have relied on the Cold War-era Soviet Ilyushin IL-72 for their large-scale air transport requirement - and the Y-20 certainly showcases some similarities to the proven Russian offering while being dimensionally different physically but the same in battlefield role. When it reaches operational-level capabilities, the Y-20 will form a powerful arm of the PLAAF (People's Liberation Army Air Force) and take-on both military- and humanitarian-minded roles while perhaps projecting an appealing end-product to the foreign market requiring a budget-conscious alternative to more expensive Western and Russian offerings including the American C-17 Globemaster III, the Russian Ilyushin IL-76 (and newer Antonov An-70) and the French Airbus A400M Atlas - the Y-20 is thought to be comparable to all of these airframes in scope and function.
For its general outward configuration, Xian engineers elected for several notable tried-and-true design elements when constructing their Y-20 - design elements pioneered in the successful American Lockheed C-141 Starlifter of the 1960s. The Chinese design relies a deep and wide fuselage for its cargo hold with the flight deck at the extreme front and a "T-style" tail with high-mounted horizontal planes at the rear. This allows the tail section to be elevated from the ground and afford access to a rear powered cargo door when accepting or extracting various cargo types. The elevated tail section forces the main portion of the fuselage to remain rather low on the ground when the aircraft is at rest. As such a large collection of rubber tires are added to the reinforced main landing gear legs -a total of twelve wheels - to support the sheer mass of the airframe. The nose is supported by a standard two-wheeled leg unit. The undercarriage is said to comply with expected "rough-field" operations - a requirement of such aircraft in the modern world.
The Y-20 is given high-mounted monoplane wings with slight sweep along their leading edges and lesser sweep along their trailing edges. This allows engine nacelles to be fitted as underslung units, two to a wing, and provide the ground clearance needed for an aircraft expected to have much traffic around itself when landed. The engines are of local Chinese production though of Russian origin - the same as powering the aforementioned Cold War-era IL-76 (Saturn/Soloviev D-30KP) and the Xian H-6 strategic-bomber-turned-missile-carrier. Wings feature triple-slotted trailing edge flaps and full-span slats which, when coupled with the high-mounted wings and basic four-engined arrangement, allows for the required operational ranges as well as strong low-speed handling and performance characteristics.