Essential Air Service

Essential Air Service (EAS) is a U.S. government program enacted to guarantee that small communities in the United States, which, prior to deregulation, were served by certificated airlines, maintained commercial service. Its aim is to maintain a minimal level of scheduled air service to these communities that otherwise would not be profitable. This came in response to the Airline Deregulation Act, passed in 1978, which gave U.S. airlines almost total freedom to determine which markets to serve domestically and what fares to charge for that service.
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