WASHINGTON — A Canadian subsidiary of the Connecticut-based military contractor the United Technologies Corporation pleaded guilty on Thursday to federal charges that it had illegally helped the Chinese government develop an attack helicopter now in service there.

As part of a settlement with the Justice and State Departments, the military contractor, the Canadian subsidiary and another American subsidiary agreed to pay more than $75 million to the departments for making false statements to federal authorities.

The helicopter, known as the Z-10, seats two people and is designed mainly to attack tanks, armored vehicles and other ground forces. It is being mass produced in China.

The Canadian subsidiary, the Pratt & Whitney Canada Corporation, violated the Arms Export Control Act by providing the Chinese with 10 engines to power Z-10 helicopters in 2001 and 2002, according to an announcement by the United States attorney’s office for the District of Connecticut. Technology for the engines, the authorities said, had originally been created for United States military helicopters.