Here’s a list of key terms and lingo to help you navigate airline stories:
Available Seat Miles
A measure of capacity on a plane or train. Calculated by multiplying the number of seats by miles traveled.
Group of flights scheduled to leave a hub (see below) airport at about the same times for connecting purposes (see below).
The practice of denying a seat to a passenger with a confirmed reservation when a flight is oversold (see below). Bumped passengers must be compensated under U.S. law.
A right granted by some governments to foreign airlines to operate domestic flights within their country. Cabotage is forbidden in the United States.
A marketing agreement under which two or more airlines share a two-letter designator code used in computerized reservations systems, so it appears that itinerary is on one airline. Most often used by major airlines and commuter/regional partners (see below).
A small airline that usually operates under contract to a large airline to carry passengers from small towns to their hub. These carriers, also known as regionals, usually operate under a derivative of a major carrier’s name, such as American Eagle or Delta Connection, and may be either independent companies or subsidiaries of a large airline.
A flight itinerary that involves changing planes, usually at a hub airport (see below).
Contract of carriage
The airline equivalent of terms and conditions when downloading a piece of software. You are assumed to have accepted this contract when you buy a ticket. It limits your rights and the airline’s liabilities when certain things go wrong, including when your luggage is lost on international flights.
Cost per ASM
The key measurement of an airline’s operating expenses. The bookend component of yield (see below).
Direct Flight – one that goes from one city to another without involving a change of planes. A direct flight is NOT necessarily nonstop.
Fixed-Base Operator (FBO)
A company that operates a general-aviation (see below) airport or general-aviation portion of a commercial airport, under contract to an airport authority or municipality.
Private or corporate aircraft, as opposed to commercial flight operations.
A route system in which an airline funnels most of its flights through several large airports where passengers have to change planes. Most domestic U.S. airlines use a hub and spoke system, with Southwest Airlines being a notable exception.
The percentage of available seats occupied by paying passengers. A key measure of operating performance for airlines and Amtrak.
The “major-airline” part of a route network that also involves regional airline partners. Mainline employees are covered by their own union contracts and are usually paid significantly more than employees at partner carriers.
An airplane with one aisle between the seats.
A key measure of service if somewhat of a misnomer. The definition of “on-time” for regulatory purposes is a flight or train that arrives or departs within 15 minutes of its published schedule.
Origin & destination traffic, as opposed to airline traffic and passengers that travel through a hub airport and connect to someplace else.
The practice by airlines of selling more seats than exist on a flight, to protect themselves from no-shows.
The area next to terminal building where baggage is loaded and unloaded.
Passenger Facility Charge (PFC)
A fee of up to $4.50 per flight segment added onto airline tickets, to pay for airport improvements.
Short for regional jets, planes that typically have 70 or fewer seats and used to fly between cities where there is not enough passenger demand traffic to fill a larger plane like a 737.
Planes driven by piston engines with propellers rather than jet engines. These are being phased out by regional jets.
An airplane with more than one aisle running between seats.
The amount of revenue, in cents, per passenger per mile flown. This is the key measure of revenue for transportation providers.
Complex computer program intended to price each seat to get the most amount of money possible.