Kaman KMaxKaman KMax helicopter model. Kaman K MAX has a dual rotor system with two intermeshing rotors which makes the aircraft more lightweight aluminum and cheaper to maintain. Flaps, similar to those on an aircraft wing, are integrated into each rotor, giving Kaman K MAX greater control than conventional helicopters and making the aircraft the world's first helicopter designed and certified for external lifting operations. Scale 1 40. Rotorspan 13. 5