For the first time, eight NFL teams were dropped this season by commercial airline carriers that offered chartered flights, according to league sources.

American Airlines dropped the Miami Dolphins, Pittsburgh Steelers, Arizona Cardinals, Baltimore Ravens, Indianapolis Colts and Jacksonville Jaguars while United Airlines dropped the Bills and Lions. The airlines dropped the teams because they can make more money flying those planes commercially.

Teams have been forced to scramble to secure charters with other smaller companies that don't have as many planes. The move has teams concerned about potential issues getting to games if there are any mechanical issues with their primary aircraft. The NFL lets each team handle its travel arrangements individually.

Smaller companies can't subservice nearly as quickly as the bigger commercial airline carriers. Two of the airlines that teams now are using are Atlas and Omni Air International, which give priority to military charters.

The Bills actually flew to Atlanta this weekend on two NBA-owned planes operated by Delta Airlines, per league sources. The NBA signed off on Delta's request to allow it to use the league's aircraft for NFL teams -- at least until they are needed.

The decision by the commercial airline carriers to drop charter service for NFL teams is not related to players' protest during the national anthem and predates the controversy.