The original OH-6 Cayuse helicopter proved its worth during the Vietnam War in the light helicopter role.
The AC-130 Gunship in Action
The Lockheed AC-130 gunship is a heavily-armed ground-attack aircraft variant of the C-130 Hercules transport plane. The basic airframe is manufactured by Lockheed, while Boeing is responsible for the conversion into a gunship and for aircraft support. The AC-130A Gunship II superseded the AC-47 Gunship I during the Vietnam War. Read more at http://en.wikipedia.org/wiki/Lockheed_AC-130