Crash Spurs Order for Hamilton Propeller Checks

The Federal Aviation Administration on Friday ordered the grounding of any planes similar to the Atlantic Southeast Airlines turboprop that crashed Monday in Georgia if they are equipped with Hamilton Standard propeller blades that were repaired after ultrasonic inspections.

The agency also said other models of commuter planes equipped with repaired Hamilton Standard 14RF and 14SF blades must be reinspected ultrasonically within their next 10 flights. If any anomalies are found in the new inspections, those planes must be taken out of service until the blades are replaced, the FAA said.

The actions followed a call earlier Friday by the National Transportation Safety Board for urgent inspections of all Hamilton Standard model 14RF and 14SF propeller blades if they have undergone more than 1,250 flights since their last ultrasonic inspections.

That could involve grounding as many as 400 planes, and the FAA’s staff is consulting with the safety board to determine if that was the intent of the recommendation, FAA Deputy Administrator Linda Hall Daschle said Friday night.

About 15,000 propeller blades of this type are in use worldwide, including 4,900 in the United States, according to the NTSB. About 1,875 airplanes use these propellers worldwide, including more than 600 in the United States, the NTSB said.

They are used on a wide variety of commuter planes. In addition to the Embraer 120, these include the De Havilland Dash 8, ATR-42, ATR-72, ATP, Saab 340B, CASA CN-235 and Canadair CL-215T.

Both agencies have focused on a broken propeller blade in searching for the cause of Monday’s Embraer Model 120 crash, which killed five people.

In addition, both the safety board and the FAA are requiring Embraer and Hamilton Standard, which is based in East Hartford, Conn., to conduct new vibration and load tests on the propellers to better understand the stress on the blades.

The NTSB reported that the propeller blade that snapped off the Atlantic Southeast plane a few minutes before it crashed had flunked an inspection a year earlier. An “anomaly” was found but maintenance records showed it was fixed before the crash.

The plane should have been able to fly with one engine. Investigators were unsure why the plane crashed after the propeller blade on the left engine snapped soon after takeoff.