Federal investigators are focusing on fan blades as they probe the third Pratt & Whitney mid-air engine failure in as many years, this one raining down debris on houses and fields in a Denver suburb.
Boeing recommended suspending operations of the 69 in-service and 59 in-storage 777s powered by Pratt & Whitney 4000-112 engines until the Federal Aviation Administration identifies inspection protocols.
Even as investigators of the National Transportation Safety Board got to work, engine failure on another Boeing plane equipped with Pratt & Whitney engines caused debris to fall after take-off from Maastricht, The Netherlands. At least one person was injured and a car roof was punctured. The Dutch Safety Board is investigating.
The NTSB said an initial examination of the engine that caught fire Saturday over Broomfield, Colorado, showed parts separated from the engine, two fan blades were fractured and other fan blades were damaged on the tips and leading edges.
Richard Aboulafia, vice president of analysis at the Teal Group, said Monday the PW4000 engine has been in service for 34 years and more than 25 years on the Boeing 777 that was forced to return to Denver International Airport.
Although the investigation has just begun, the problem is “almost certainly a maintenance issue, not a design issue,” he said
“They all have issues. They just go through these things,” Aboulafia said.
Raytheon Technologies Corp., the Waltham, Massachusetts, parent company of Pratt & Whitney, is unlikely to falter over the long-run following the engine failure, he said.
“It will not affect the company’s competitiveness going forward,” he said.
Cowen analyst Cai von Rumohr said in a client note Monday the engine failure is “probably not a major negative” for Raytheon. Boeing 777s powered by PW4000 engines represent just 8% of the total 777 fleet, he said.