| U.S. airlines of the regulated era (1938-1978) |
| Federal regulatory agency |
Civil Aeronautics Board (CAB) |
| Certificated route carriers(1) |
International |
Air Micronesia; Mackey Airlines; Mackey Intl; Midet; Panagra; Pan Am; Resort Airlines; Samoan; South Pacific; Trans Caribbean; Uraba, Medellin and Central |
| Trunk |
American; Braniff Intl; Capital; Chicago & Southern; Colonial; Continental; Delta; Eastern; Inland; Marquette; Mid-Continent; National; Northeast; Northwest; Trans World (TWA); Western; United; Wilmington-Catalina |
| Local service |
Allegheny; Bonanza; Central; Challenger; Empire; Florida Airways; Frontier; Hughes Airwest; Lake Central; Mid-West; Mohawk; Monarch; North Central; Ozark; Pacific; Parks; Piedmont; Pioneer; Southern; Texas Intl; West Coast; E.W. Wiggins |
| Alaska |
Alaska Airlines; Reeve Aleutian; Wien |
| Hawaii |
Aloha; Hawaiian |
| Territorial |
Caribair |
| Regional |
Air Midwest; Air New England; Aspen; TAG; Wright |
| Cargo |
Aerovias Sud Americana (ASA Intl); Airlift Intl (Riddle); Airnews; Flying Tiger; Seaboard World; Slick; U. S. Airlines |
| Helicopter |
Chicago; Los Angeles; New York Airways; San Francisco and Oakland |
| Supplemental air carriers(2) |
AAXICO; Admiral (Quaker City); Air America; Air Services; Air Transport Associates; Airline Transport Carriers; American Air Transport & Flight School; American Flyers (AFA); Argonaut; California Air Charter; California Eastern; California Hawaiian; Capitol; Caribbean American; Central Air Transport; Continental Charters; Continental Sky-Van; Currey Air Transport; Economy Airways; Evergreen; Hemisphere; Imperial; Johnson; Lone Star Air Cargo Lines; McCulloch; Meteor Air Transport; Modern; Monarch Air Service; New England Air Express; Overseas National (ONA); Oxnard; Paramount (Paul Mantz); Peninsular Air Transport; President; Purdue; Rich Intl; Saturn; Southern Air Transport; Standard Air Lines; Standard Airways; S.S.W.; Trans American; Trans Intl; Trans National; Transocean; U.S. Aircoach; U.S. Overseas Airlines; Unit Export; Universal; Vance; Westair Transport; World; Zantop Air Transport; Zantop Intl |
| Not regulated by CAB |
Intrastate airlines |
AirCal; Air Florida; Alaska International Air; Arizona; California Central; Holiday; Mercer; Pacific Southwest Airlines; Paradise; Southwest Airlines |
| Uncertificated/Part 45 |
Aeroamerica; Pacific American; Twentieth Century; Viking |
| Air travel clubs |
Club Intl, Denver Ports of Call, Nomads, Voyager 1000 |
| Air taxi/commuter |
Oneida County Aviation; SkyWest |
| Other |
Combines(3) |
North American; North Star; Peninsular; Skycoach; South East |