The certificate attests that a new model of plane meets safety regulations. Each subsequent model of that plane to be built is also examined by the FAA as it is produced, and given its own certificate once it is ready for commercial service. Foreign-built aircraft flying to or in the United States must meet the same high standards to which U.S. manufacturers are held. Manufacturers often also issue Service Bulletins to advise carriers of safety improvements or procedures that can heighten safety. Cockpit Crew .
Pilots play a unique role in maintaining safety.
Only the pilot can decide whether it is proper to takeoff or land, for example, even though a controller may have issued clearance for these actions. The FAA sets standards for pilot training, health, experience, and qualifications. Airline pilots must pass special examinations and flight tests, and those serving as captains are required to possess many hundreds of hours of additional flying time. Every six months pilots must have their health checked, and their flying skills are tested by the FAA on a regular basis. The FAA also regulates the hours that airline pilots may work, and conducts a continual review to guarantee their high performance.