A mainline flight is a flight operated by an airline's main operating unit, rather than by regional alliances, regional code-shares, regional subsidiaries, or wholly owned subsidiaries offering low-cost operations. Mainline carriers typically operate between hub airports within their network and on international or long-haul services, using

narrow-body A narrow-body aircraft or single-aisle aircraft is an airliner arranged along a single aisle, permitting up to 6-abreast airline seat, seating in a aircraft cabin, cabin less than in width. In contrast, a wide-body aircraft is a larger airliner ...

and

wide-body A wide-body aircraft, also known as a twin-aisle aircraft and in the largest cases as a jumbo jet, is an airliner with a fuselage wide enough to accommodate two passenger aisles with seven or more seats abreast. The typical fuselage diameter is . ...

aircraft. This is in contrast to

regional airline A regional airline is a general classification of airline which typically operates scheduled passenger air service, using regional aircraft, between communities lacking sufficient demand or infrastructure to attract mainline flights. In North ...

s, providing feeder services to hub airports operating smaller

turboprop A turboprop is a Gas turbine, gas turbine engine that drives an aircraft Propeller (aeronautics), propeller. A turboprop consists of an intake, reduction drive, reduction gearbox, gas compressor, compressor, combustor, turbine, and a propellin ...

regional jet A regional jet (RJ) is a jet airliner, jet-powered regional airliner usually defined by having fewer than 100 seats. The first aircraft considered part of this category was the Sud-Aviation Caravelle in 1959, followed by Douglas DC-9, BAC O ...

aircraft, or

low-cost carrier A low-cost carrier (LCC) or low-cost airline, also called a budget, or discount carrier or airline, is an airline that is operated with an emphasis on minimizing operating costs. It sacrifices certain traditional airline luxuries for cheaper fa ...

subsidiaries serving leisure markets. In the United States, examples of mainline

passenger airline An airline is a company that provides air transport services for traveling passengers or freight (cargo). Airlines use aircraft to supply these services and may form partnerships or alliances with other airlines for codeshare agreements, in w ...

flights include those operated by

American Airlines American Airlines, Inc. is a major airlines of the United States, major airline in the United States headquartered in Fort Worth, Texas, within the Dallas–Fort Worth metroplex, and is the Largest airlines in the world, largest airline in the ...

Delta Air Lines Delta Air Lines, Inc. is a Major airlines of the United States, major airline in the United States headquartered in Atlanta, Georgia (U.S. state), Georgia, operating nine hubs, with Hartsfield–Jackson Atlanta International Airport being its ...

, and

United Airlines United Airlines, Inc. is a Major airlines of the United States, major airline in the United States headquartered in Chicago, Chicago, Illinois that operates an extensive domestic and international route network across the United States and six ...

; but not flights operated by

Envoy Air Envoy Air Inc. is an American regional airline headquartered in Irving, Texas, in the Dallas–Fort Worth metroplex. It is a wholly owned subsidiary of the American Airlines Group and it is paid by fellow group member American Airlines to sta ...

Mesa Airlines Mesa Airlines, Inc. is an American regional airline headquartered in Phoenix, Arizona, Phoenix, Arizona. Mesa operates and maintains a fleet of Embraer E-175 Aircraft that are scheduled, marketed and sold by United Airlines as United Express. ...

Executive Airlines Executive Airlines, Inc. was a Puerto Rican-based regional airline headquartered at Luis Muñoz Marín International Airport in Carolina, Puerto Rico, the main airport for the United States territory, near the capital of San Juan. The airline w ...

Piedmont Airlines Piedmont Airlines, Inc. ( ) is an American regional airline headquartered at the Salisbury Regional Airport in Wicomico County, Maryland, near the Salisbury, Maryland, city of Salisbury. The airline is a wholly-owned subsidiary of the American ...

, or

PSA Airlines PSA Airlines, Inc. is an American regional airline headquartered at Dayton International Airport in Dayton, Ohio. The airline is a wholly owned subsidiary of the American Airlines Group and it is paid by fellow group member American Airlines ...

with regional jets or the services of regional airline marketing brands such as American Eagle,

Delta Connection Delta Connection is a brand name under which Delta Air Lines has air service agreements with domestic regional air carriers that feed traffic to their network by serving passengers primarily in small and medium-sized cities in the domestic mark ...

, or

United Express United Express is a regional airline network that supports United Airlines operations, primarily by serving smaller cities and connecting traffic to United's main hubs. Representing six percent of United's total capacity for 2024, United Express ...

aboard lower-capacity narrowbody jets and turboprop aircraft, such as those produced by

Embraer Embraer S.A. () is a Brazilian multinational aerospace corporation. It develops and manufactures aircraft and aviation systems, and provides leasing, equipment, and technical support services. Embraer is the third largest producer of civil air ...

or Bombardier, that do not have transcontinental range. U.S.

legacy carriers In the United States, a legacy carrier is an airline that was once economically regulated by the Civil Aeronautics Board (CAB) during the period of airline regulation 1938–1978 or can trace its origin to one that did. The CAB was a now defunct f ...

may operate branded mainline services using the same flight crews and AOC as that of their mainline operations. For example, United p.s. and American Flagship Service cater to the medium-haul transcontinental business segment. Short-haul air shuttles, such as Delta Shuttle, operate at high frequency intervals between busy city pairs. Previously, U.S. legacy carriers operated low-cost air services within their mainline operations to compete with

low-cost carriers A low-cost carrier (LCC) or low-cost airline, also called a budget, or discount carrier or airline, is an airline that is operated with an emphasis on minimizing operating costs. It sacrifices certain traditional airline luxuries for cheaper far ...

; these operations were short-lived and included brands such as Continental Lite,

Song A song is a musical composition performed by the human voice. The voice often carries the melody (a series of distinct and fixed pitches) using patterns of sound and silence. Songs have a structure, such as the common ABA form, and are usu ...

(Delta), and Ted (United). Outside the U.S., low-cost carrier subsidiary airlines are more common, with examples including Air Canada Rouge, Jetstar Airways (subsidiary of

Qantas Qantas ( ), formally Qantas Airways Limited, is the flag carrier of Australia, and the largest airline by fleet size, international flights, and international destinations in Australia and List of largest airlines in Oceania, Oceania. A foundi ...

), and

Eurowings Eurowings GmbH is a Germany, German low-cost carrier headquartered in Düsseldorf, North Rhine-Westphalia, and a wholly owned subsidiary of the Lufthansa Group. Founded in 1996, it serves a network of domestic and European destinations and main ...

(subsidiary of

Lufthansa Deutsche Lufthansa AG (), trading as the Lufthansa Group, is a German aviation group. Its major and founding subsidiary airline Lufthansa German Airlines, branded as Lufthansa, is the flag carrier of Germany. It ranks List of largest airlin ...

). An airline carrier's

collective bargaining agreement A collective agreement, collective labour agreement (CLA) or collective bargaining agreement (CBA) is a written contract negotiated through collective bargaining for employees by one or more trade unions with the management of a company (or with an ...

with flight crews stipulates the maximum seating capacity of regional aircraft; as such, any aircraft that exceeds this capacity must operate as a mainline flight. The converse is not the case; mainline flight crews, with proper

type rating A type rating is an authorization entered on or associated with a pilot license and forming part thereof, stating the pilot's privileges or limitations pertaining to certain aircraft type. Such qualification requires additional training beyond ...

s, may operate aircraft that are smaller than typical mainline aircraft.

Mainline subsidiary carriers and airline within an airline brands

Notes: ¹Though not part of the main "legacy airline" or "flag carrier", these particular airlines are often described as "regional airlines" by the mainline airline counterparts they are affiliated or owned by.
²These airline businesses resultant of airline liberalization in Europe, really do not have a "mainline brand", but do have unified brandings across multiple individual airline certificates forming "virtual airlines" much like the American Eagle,

, and

banner branded regional airlines in the United States.

North American mainline carrier's regional affiliates

Notes:
¹ Branding used for regional feeder service and commuter flights. Operated either by a regional subsidiary or under contract by an independent regional airline.
²These airlines are independent and not subsidiaries of mainline air carriers.
³ These independent airlines operate regional aircraft under codeshare agreements with a mainline carrier.
⁴ Independent airlines operating under a capacity purchase agreement with their mainline partner

Notes

References

AA and early references to mainline, regional and B-scale.
Business model of new Airlines like GLO not operating their own aircraft but leasing them from other certificated air carriers, and creating their own airline brand without the actual assets of a true airline. {{DEFAULTSORT:Mainline (Flight) Airline types Civil aviation

Mainline subsidiary carriers and airline within an airline brands

North American mainline carrier's regional affiliates

See also

Notes

References