AMR felt they were being dealt with unfairly by the airport authority in SJU. Low cost airlines were being charged far less then the legacy airlines. They threatened to leave and the airport did not believe it. In the end they pulled 50 ATR's out and dropped 10 mainline flights to SJU. It probably was a good thing overall as it has served as a warning to other airports and even government agencies. Florida as a example recently agreed to phase in equal fuel taxes for all airlines. JetBlue, Spirit and Southwest will have to pay the same higher tax rate as Delta, United and AMR.
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