U.S. regulators ordered airlines to avoid flying Boeing Co. 787 Dreamliners and 747-8 jumbo jets with General Electric Co. engines near thunderstorms after some of the planes experienced ice buildup.
An airworthiness directive published online Tuesday in the Federal Register instructs pilots to fly clear of high-altitude icing conditions that could sap thrust and damage GEnx engines. The Federal Aviation Administration move follows Japan Airlines Co.’s shift to other jets from 787s on some Asia routes.
The icing risk adds urgency for pilots to steer clear of thunderstorms already shunned because of potentially deadly lightning and turbulence. Jets flying at high altitudes through tropical zones can be at risk from powerful storms that promote the formation of performance-sapping ice, according to GE.
“It’s a relatively rare phenomenon because it requires just the right meteorological conditions,” said Hans Weber, president of San Diego-based aviation consultant Tecop International Inc.
“These crystals have been found in all engines at high altitudes near thunderstorms.”
