The U.S. Department of Transportation has announced a new ruling that will provide airline passengers with more transparency when booking “code-sharing” flights.

Code-sharing refers to one or more airlines using their designator codes to process bookings and sell tickets on flights operated by another carrier. The practice has grown in recent years, particularly because regional/commuter airlines now represent more than 50 percent of all daily domestic scheduled airline departures.

Under the new law, airlines and other online ticket sellers will be required to disclose code-sharing arrangements on the same screen and next to the itinerary. All websites must be modified within 60 days.

Consumers Union recommended this action through my participation on the DOT’s Future of Aviation Advisory Committee. Greater transparency on code-shared flights was among the 23 recommendations the FAAC presented to DOT Secretary Raymond LaHood on Dec. 15th [PDF].

In announcing the new rule, Lahood stated: “When passengers buy an airline ticket, they have the right to know which airline will be operating their flight. For years we’ve required airlines to inform consumers about code-sharing arrangements, and we’ll be monitoring the industry closely to make sure they comply with the provisions of the new legislation.”

Back in October, we noted here that the National Transportation Safety Board held a symposium that examined code-sharing from a safety standpoint. This included analyzing recent fatal accidents of code-shared flights, including the 2009 crash in Buffalo of Colgan Air Flight 3407 operating as Continental Connection.

—William J. McGee