Following is a transcript of the video. This helicopter has dual-crossing rotors for increased precision The K-MAX uses a unique double rotor system where the two rotors cross each other.

At 37 meters long with a wingspan-like dual rotor design, the Mil V-12 set world records for lifting power. This video ...

Although the helicopter, aptly named Ingenuity ... and a more traditional multicopter is the choice to make it a dual-rotor design. There would have been no way to go with a quadcopter design ...

Lockheed Martin has completed the delivery of ten S-70i Black Hawk helicopters to the Philippine Department of National ...