FedEx employs contract carriers that use their own vehicles for home deliveries.

FORBES: Start the Ground War

The smaller carriers that do have a significant percentage of hub-and-spoke routes, such as Mesa Air Group and SkyWest, do so as contract carriers for the Big Six: AMR, Delta Air Lines , UAL, Continental Airlines, Northwest Airlines and U.S. Airways.

FORBES: Magazine Article

The airline has been attempting to contract with outside carriers to boost its schedule, but charters have been difficult to schedule this late into the holiday weekend.

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