The Federal Aviation Administration's Air Traffic Organization sent approximately 3,600 air traffic control managers and supervisors to Atlanta, Georgia over a period of three weeks this month, at a cost of $5 million dollars.

The conference, which the FAA said was to go over a new contract with the National Air Traffic Controllers Association that went into effect Oct. 1, was held at the 4-diamond Omni Hotel in downtown Atlanta.

Approximately 1,200 managers and supervisors arrived each week by coach bus from the airport.

As part of the hospitality for the FAA, the Omni Hotel threw a large cocktail party for the air traffic control managers.

null

Here, FAA conference attendees socialize while on afternoon break among the Omni Hotel's holiday décor.

An FAA whistleblower told ABC News that the Atlanta meetings were "extravagant" and that "one would think a PowerPoint or even a videoconference would suffice." "This waste of money is just inexcusable," the whistleblower said.

The FAA told ABC News that "given the complexity of the contract and the need for managers to fully understand it, the training had to be done face-to-face not through a memo or webcast."

At night, the FAA managers made the rounds of Atlanta bars, drinking and dancing.

The hotel's lobby bar was packed each night of the conference with loud conference attendees.

Tom Schatz of the nonprofit group Citizens Against Government Waste said taxpayers should be outraged. "Anyone who is flying, whose flight has been delayed or canceled, could find a lot better usage for five million dollars for the FAA," said Schatz.