The Bell Cobra gunship was used in Vietnam. The weapons officer sat in front and the pilot in the rear however both seating positions had the capability of handling both jobs. The twin engine version is still in use with the Marines.
Stack O' Hueys Want to see it for real? Just north of Houston, on the way to Tomball, you can see them flying in and out of the airbase there. Added bonus!, a little further up the road you can see the Goodyear blimp as its tethered at its base of operation.