Proper posture starts with a good understanding of the muscles that are involved in posture. Several different muscles are responsible for maintaining upright posture, and over time, poor posture can cause these muscles to lose strength.
Air Force. A major in the Air Force typically has duties as a senior staff officer at the squadron and wing level. In flying squadrons majors are generally flight commanders or assistant directors of operations. In the mission support and maintenance groups majors may occasionally be squadron commanders.
Most countries' armed forces employ air traffic controllers, often in most if not all branches of the forces. Although actual terms vary from country to country, controllers are usually enlisted. In some countries, all air traffic control is performed by the military. In other countries, military controllers are responsible solely for military airspace and airbases; civilian controllers maintain airspace for civilian traffic and civilian airports.