The specific duties and responsibilities will vary by job. Some aviation industry professionals will be in charge of piloting an aircraft, while others, such as flight attendants, will work directly with clients during a flight to ensure their comfort and safety. There are also aircraft engineers, whose main job is to create the aircraft and propulsion systems, and aircraft assemblers, who put together the aircraft. Aviation is a large field where some people work behind the scenes while others are on stage, but every single role is important.