Ongoing flight research of autonomous dual lift operations are currently being conducted by the U.S. Army Aviation and Missile Research, Development and Engineering Center Aviation Development Directorate, know as ADD, at Moffett Field. 

In the photo, two autonomous RMAX helicopters are carrying a single 20 pound payload through a set of hover and low-speed maneuvers.

Planned testing for the remainder of the month includes forward-flight maneuvering in different formations using a mix of trajectory planning and feedback mechanisms for load cable tension balancing. The two RMAX helicopters are an autonomous flight resource developed in-house by ADD and have been used for numerous flight experiments since 2002.

(Image Credit: U.S. Army)