US orders faster inspection of jet engines linked to death
By ALAN LEVIN, RICHARD CLOUGH AND MARY SCHLANGENSTEIN | Bloomberg | Published: May 16, 2018
Airlines need to speed the inspection of older jet engine fan blades like the one that led to a passenger death after it broke loose last month on a Southwest Airlines Co. flight, U.S. regulators said Wednesday.
The Federal Aviation Administration issued a new directive to operators of the CFM56-7B engine, one of the most popular makes in the world, based on findings in the investigation and a review by the manufacturer, according to a notice set to be published in the Federal Register Thursday.
"The FAA is acting to ensure an extra measure of safety," the agency said in an emailed statement.
A woman was partially sucked though a window on April 17 when a fan blade on a CFM56-7B engine broke loose, shredding the cover of the front of the engine and spraying metal parts into the aircraft. A buckle on the engine inlet struck and broke the window, causing the cabin to rapidly depressurize, according to the National Transportation Safety Board.
A crack on the blade had gradually grown until it fractured, according to preliminary findings in the NTSB investigation.
The new order, which replaces one issued earlier this month, requires airlines to inspect the the fan blades with the highest risk of failure by June 30, using guidance from engine-maker CFM International Inc. The company is a joint venture between General Electric Co. and France's Safran SA.
Those blades are the ones that have made the most number of flights, also known as a cycle, according to the order. Other provisions in earlier FAA orders remain in effect. They call for blades that have made more than 20,000 flights to be inspected by the end of August. After the inspections, blades must be reinspected every 3,000 cycles.
The latest order is designed to make sure the highest priority inspections occur first, according to an emailed statement from CFM.
While Southwest has completed its inspections without finding any cracks like the one that triggered the accident, the airline has sent "several dozen" blades, including some with coating anomalies, to GE for additional testing.
The airline doesn't expect GE's more detailed inspections to find cracks. "I don't think we'll have any findings with those, but there is one extra step we wanted to take with that," airline Chief Executive Officer Gary Kelly said. Southwest also is auditing its internal records to confirm that every blade has been inspected, he said.
The tests on the fan blades use ultrasound or electric currents to sense cracks beneath the surface of the titanium blades.