The National Transportation Safety Board sent letters Monday to UPS and the Independent Pilots Association revoking their "party status" into the investigation of last summer's crash during a landing approach at Birmingham-Shuttlesworth International Airport.
The board said both the company and the union violated rules by making public statements about the cause of the accident before the investigation is finished.
Earlier this month, in conjunction with the one-year anniversary of the crash of UPS Flight 1354, the union released a statement blaming the accident on the flight crew's fatigue and calling for a change in the rules governing cargo pilots' schedules.
A UPS spokesman responded on an aviation website where the union release was posted, issuing statement asserting that the crew's schedule met regulations.
The NTSB still has not decided on the probable cause of the crash, and it told both the union and the company that they should not have made public statements speculating on what cause the twin-engine cargo jet to fly into trees and crash short of the runway. The flight had originated in Louisville, Kentucky.
The safety agency has scheduled a final meeting for Sept. 9 to determine the cause of the crash.
Board members discussed the problem of pilot fatigue at a hearing on the crash earlier this year. The UPS pilots complained about the company's tiring work schedules at the start of the fatal flight, and then made errors shortly before the plane hit trees and flew into a hillside, exploding into flames.
Capt. Cerea Beal Jr. and co-pilot Shanda Fanning were killed as they tried to land on the airport's secondary runway, which was not equipped with a full instrument landing system to help keep planes from coming in too high or too low.
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