A bipartisan group of lawmakers unveiled a bill Tuesday aimed at ending the Federal Aviation Administration's sometimes cozy relationship with the airline industry and reversing purported complacency on safety oversight.

Several House Democrats and Republicans led by Public Works and Transportation Committee Chairman James Oberstar, D-Minn., said they were introducing the bill to force changes on the FAA that the agency has been reluctant to make on its own.

"We don't trust the FAA to do this on their own, and that's without regard to whatever administration is in place," Oberstar said. "There is a culture at the FAA that is evolving and changing and we need to change it more."

The bill would:

— Create an independent Aviation Safety Whistleblower Investigation Office within the FAA that would investigate safety complaints.

— Direct the FAA to stop treating airlines as customers and halt the practice of allowing airlines to choose which FAA inspectors will inspect their operations.

— Set a two-year "cooling off period" before FAA inspectors or FAA employees who supervise inspectors can go to work for an airline.

— Require the FAA to rotate principle maintenance inspectors between airline oversight offices every five years.

— Require the FAA to review its database of safety compliance reports monthly in order to spot trends and take timely action.

FAA officials weren't immediately available for comment.

Late last month, the Department of Transportation launched an investigation into FAA practices, including how the agency reviews flight risk, its air carrier compliance measures and its oversight of maintenance practices.

In April, FAA inspectors testified at a congressional hearing that their jobs were threatened when they reported maintenance and inspection problems with some airlines.

"Unfortunately the FAA seldom acts until they are pushed to act," said Rep. Jerry Costello, D-Ill. "That's one of the reasons why we've held so many hearings ... If I had my way, there would be major changes in personnel at the FAA."

With only a few months left on Congress' legislative calendar, the bill's sponsors acknowledged that it will be difficult to enact the measure this year. But they said want to send FAA a strong message.

Rep. Dan Mica, the ranking Republican member of the committee, called the bill "a shot across FAA's bow."