Mesa Airlines filed for Chapter 11 banktrupcy protection Tuesday, hoping to shed planes it no longer needs.

Mesa's filing is part of broader problems the airline has been experiencing with its operations as demand for air travel fell over the last year because of the economic downturn.

Contract carriers such as Mesa have traditionally been able to maneuver through tough economic times because their revenue is guaranteed through deals with major airlines.

Regional jets are smaller than the planes that large airlines use on most of their routes. They are often used to bring travelers to hub airports, where they can connect with other flights.

During the recession, as big airlines cut seats, Mesa struggled. Mesa currently operates flights as Delta Connection, US Airways Express and United Express.

Flying as United Express, Mesa had about 1.5 percent of Denver International Airport's market share in October.