The Chinese military evaluated the Agusta A129 Mangusta in the mid 1980s. In 1988 a defence agreement was signed between the USA and China authorising the sale of AH-1 Cobra attack helicopters to China, along with permission to produce the BGM-71 TOW in China under licence. But just as China was preparing to do further evaluations, China was sanctioned by the west after the Tiananmen Square protests of 1989. Afterwards, as China turned to Eastern European countries for help in the period between 1990 through 1991, the colour revolutions also prevented China from obtaining attack helicopters.
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After the continuous failures in introducing heavier helicopters of foreign origin to China, the 6-ton class China Medium Helicopter (CHM) program [1] was started in 1994 by China, with the 602nd and 608th Research Institutes as the leading designers. Under this ostensibly civilian program, various key western helicopter manufacturers provided considerable technical assistance to the later WZ-10 development program, including Eurocopter (rotor installation design consultancy), Pratt & Whitney Canada (PT6C turboshaft engine) and Agusta Westland (transmission)
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Some foreign assistance from South Africa has been confirmed, which provided limited help in the area of flight stability based on the experience from designing the Denel AH-2 Rooivalk. South Africa refused further Chinese requests for assistance and no contact was made after 2001.
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The transmission system was developed with the help of Agusta Westland.
