Trainer aircrafts are designed for both primary and advanced training of pilots of civil or military aviation. They are designed on the basis of ordinary aircraft by converting them into double variants ("dual control aircraft") with the possibility of dual paired control, less often - they are designed anew. Internationally accepted practice: after the design of a new type of aircraft, then followed the design of a "dual control aircraft" for more detailed training of pilots on this type of aircraft, often on "dual control aircraft", fully or partially the possibilities are kept for combat use. Trainer aircraft plastic model kits are produced on the same scale as other aircraft models: 1:32, 1:48, 1:72, 1:144.