In 1963, Bell Helicopter Model 47G-2 registered N6723D was modified with the original Model 47 quadricycle landing gear, cut-down Piper Comanche wings, a larger ventral fin, and a tilting rotor mast to evaluate a helicopter configuration that could lift heavier loads with a rolling takeoff than a conventional helicopter. The wings retained its flaps and ailerons. (At one point, the fuel tanks were moved to the wing tips.) Nicknamed Wing Ding, it was first flown that May by Floyd Carlson and Lou Hartwig and demonstrated cruise speeds of up to 100 mph. The wings proved to be over-large for acceptable handling qualities and performance but the evaluation resulted in smaller wings being used on the Bell attack helicopters.