The Model was inspired by the CH 47 Chinook an the orange Coast Guard Helicopter. I did not like so much the aircraft tail at the Coast Guard Helicopter and the Idea for a tail with a ramp was initiated. During building the Heli, I had the idea to synchronise the Rotors with a gear. The 4x4 Technic Frames in the Ceiling allow to pass through very simple with technic axles. I had a 9V Motor left over. The next idea was to install it in the aft Rotor-Tower and I managed it. It works with an exterior batterie box, witch will be soon be empacked in a Fuel Truck... The light & sound box does not work. I need the large one with 6 AA batteries inside. For Exhibitions a 9V Train Regulator can be used. Maybe I change the gray engines into black soon, they are on the BL wishlist.