During a routine training flight near NAS Fallon (NV), two CH-46s from HMM-764 were executing a tactical formation flight but they came too close to eachother. One Frog turned in the formation over the other. The rotor blades of the lower helicopter chopped through the fuselage just behind the crew front door of this 153358, killing two Marines. The pilots managed to autorotate to the ground and survived. The crew in the other aircraft were uninjured. Here 153358, in the old green colours, can be seen at the flightline of El Toro.