Certificated Air Carriers

FAA Certificated

FAA Certificated Airlines are airlines in the U.S. which primarily operate large aircraft in accordance with PART 121 regulations, but also include airlines with operating certificates with the provision of carrying passengers or cargo for hire under PART 135 regulations and operating certificates as well.

Other Government Regulated Airlines

ICAO Regulated Airlines

Scheduled Air Carriers

Mainline

Mainline Air Carriers, are airlines which have a regional airline or feeder airline fleet component separate and apart of the operating regulations and restrictions which govern the larger main airlines operating certificate, staffing, and fleet.
- Flag (Airline) Carriers
- Legacy (Airline) Carriers, typically used disparagingly as a label of inefficiency by smaller leaner carriers.
- Network (Airline) Carriers are usually larger airlines with an international route network which actively markets connecting flights via airline hub airports and provides the respective transfer services for passengers and their baggage. Additionally, network airlines, tend to have larger mainline narrowbody aircraft among their multiple fleet mix types (contrary to a typical low-cost carriers single fleet type), provide services to smaller communities through code-share regional airline affiliates, subsidiaries, capacity purchase agreements, or franchise partnerships.

Non-Mainline

Non-mainline
- Regional airlines, Independently marketed and branded regional airlines such as Silver Airways and Great Lakes Aviation are increasingly rare in the U.S. For the most part, regional airlines are "non-mainline" airlines with aircraft seating up to 100 passengers (and in the United States typically no more than 74 passengers due to SCOPE clauses in effect which Pilots and Employees have at mainline carriers in regards to outsourcing flights to other airlines) and operating over shorter non-intercontinental distances in assocation and on behalf of mainline airlines.
- Feeder Airlines are airlines whose primary business model is designed around connecting and supplying passengers or cargo for Flag, Network, Legacy, or Mainline airlines. Most modern regional airlines act as feeder airlines in the mainline airlines regional marketing brand and aircraft livery.
- Commuter airlines, serve smaller communities; and are sometimes known as regionals, feeders, air taxis, and endearingly or disparigingly as "puddle jumpers." With the advent of a new generation of air taxi Aerospatiale Corvette style VLJs - Very light jets, such terminology may be in flux.

Specialty Positioned

Boutique airline companies are generally smaller certificated air carriers flying typically mainline sized type equipment which offer special features such as an all discount premium cabin much like the former MAXjet Airways or offering niche type premium cabin services such as live satellite inflight entertainment and Internet, often out of a highly populated or transited hometown of major urban airline hub. Sun Country Airlines
- All business class airlines are ones which offer all premium cabin services among their fleet such as the former business class only - Midwest Express Airlines, Silverjet, or the present OpenSkies would a current example.
- Hybrid airlines are a type of specialty airline which tend to attract those with discretionary incomes who choose to pursue airlines mastering cutting edge technology and service levels in addition to offering traditional airline features such as airline lounges, interline ticketing and luggage transfer, frequent flyer plans allied with airline alliances all while still attracting the selective customer wanting the latest level of value and quality air service. Alaska Airlines
- Niche features airlines offer such thigs as chic branding, premium cabin options, live satellite inflight entertainment and internet, wrapped in a package that, which mimics the pricing strategy of low-cost or start-up carriers. Jetblue Airways and Virgin America are a few examples in the United States which tend to fit this model.
Discount airline companies
- Low-Cost Carriers, giving a "basic", "no-frills" and perceived inexpensive service and typically used by larger established airlines in a disparaging manner.
- ULCC's - Ultra Low Cost Carriers - another type of specialty airline carrier pioneered by the likes of the original People Express Airlines and taken to the next level of "cheap" and passenger unfriendly policies such as added fees, rigid "not our problem" or fault purchase rules by the likes of EasyJet and Spirit Airlines among others.

Start-Ups

Newly founded certificated air carriers
- Start-Up carriers - are newly founded air carriers, which due to being a new business, supposedly have lower labor and operating costs than the airline peers they are competing for passengers with. Start-up models may utilize, mainline or regional sized aircraft, and and may encompass a broad range of flying such as operating as a feeder airline for a mainline airline or operating as an independently branded airline (though rare), utilizing regional aircraft sized equipment. Any sort of flying which may provide a start up with a competitive niche against established carriers.

Non-Scheduled Air Carriers

Charter Airlines

- Charter airlines, operating outside of regular scheduled intervals

Uncertificated Airline Businesses

Pseudo Airlines

- Air shuttles though not certificated airlines typically; Shuttles of the past have become slot assets that were and are spun off as in the case of New York Air to the Pan Am Shuttle or as independent certificated operations as in the case of the Eastern Airlines Shuttle to the Trump Shuttle,
- Airline Marketing Brands such as American Connection or US Airways Express, often mistaken for independent and fully certificated airlines
- Airlines (marketing) within an Airline (Carrier) - Metrojet, Delta Express etc.
- Virtual Airlines

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