From the "Final Assembly" the aircraft passes on a "Test-flying" department. Besides other things there is made an aircraft refueling, de-preserving engines, resp. getting the aircraft to work generally. On this section is also completely finished interior of the airplane (assembly seats and upholstery according to customer requirements), plus emergency cabin and oxygen apparatus. Thereafter, the pre-flight making is carried out with subsequent test flights. At the company airport there is tested engine, navigation and carried out other steps to verify the reliability and readiness of the aircraft. Finally, when the aircraft passed the test-flying, it is handed on the appropriate authorization authorities for obtaining permissions to operate, and subsequently to a customer.