1. It makes a lot of difference to the controller to know whether you are a Boeing 737, a twin Commanche, or a Cessna 150. Include this information in your initial call, but then omit it in subsequent transmissions. Terms such as "helicopter" "homebuilt" "ultralight" and "glider" may be used instead of the actual manufacturer. This quickly indicates to the air traffic controller and other traffic on the frequency information on your speed, your manoeverability and appearance.