Any company that intends to provide air transportation service must first obtain two separate authorizations from the Department of Transportation: “safety” authority in the form of an Air Carrier Certificate and Operations Specifications from the Federal Aviation Administration (FAA).

The most common types of operations are:

  • Part 91: General Aviation with general flight operating rules, such as crew rest and duty and aircraft operations within certain weather conditions. Some commercial operations may operate under Part 91 rules.
  • Part 121: Scheduled Air Carriers with Domestic, Flag, and Supplemental Operations, both regional airlines and major airlines.
  • Part 125: Commercial flights by airplanes with the capacity of 20 or. more seats and maximum payload capacity of 6,000 pounds or more.
  • Part 129: Foreign Air Carriers and Foreign Operators of U.S. Registered Aircraft Engaged in Common Carriage.
  • Part 133: Rotorcraft External-Load Operations
  • Part 135: Commuter and On Demand Operations, including corporate, government and helicopter operations.
  • Part 141: Flight schools
  • Part 142: Training centers