The term 'helicopter, type of' can be solved by the 8-letter word 'autogiro'. An autogiro is a type of aircraft that was developed in the 1920s as an early form of the helicopter. It has a rotor for lift and a propeller for thrust, and it is able to take off and land vertically. Autogiros were used for a variety of purposes, including aerial photography, crop dusting, and passenger transport. They were eventually replaced by helicopters, which are more efficient and have greater maneuverability.