Boeing said the AH-6i displayed flight characteristics and handling maneuvers during its maiden 36-minute flight over the Arizona desert in September.
Al Winn, vice president of the Apache attack helicopter program at Boeing, said test pilots have conducted subsequent flights to explore the characteristics of the AH-6i.
The AH-6i has a combat-proven design with an integrated and qualified weapons system.
"The rapid integration of the avionics suite and cockpit proves the value of the Boeing open systems architecture, originally developed for the AH-64D Apache Block III, to facilitate quick configuration and integration of new technologies," said Winn.
Boeing launched prototype work in March, incorporating the highest payload in its class.
The aircraft is intended for international customers.