The engine of the Pratt & Whitney plane that caught fire and forced a United Airlines pilot to make an emergency landing shortly after take off from Denver has seen similar eruptions on at least two other flights, have experts said Monday.
Three years ago, a fan blade broke on one of the PW4000 engines powering another United Airlines Boeing 777-200 aircraft, this time over the Pacific Ocean on a flight from San Francisco to Honolulu.
And in December, two fan blades of the same type of engine broke on a Japan Airlines Boeing 777-200 flying from Naha to Tokyo.
As in Denver, the pilots of these two flights were able to land their planes safely and no one was injured.
“This is not the first time this has happened,” aviation expert Greg Feith said on NBC’s “Today” show, referring to the malfunction of the PW4000 engine.
But after Saturday’s fiery episode in the Colorado skies, images of which went viral on social media, Boeing has grounded all of its older 777-200 planes around the world while federal investigators inspect the PW4000 engines of the planes, which are only used by United. Airlines in the United States and airlines in Japan and South Korea.
In particular, Federal Aviation Administration administrator Steve Dickson said inspections were “stepped up for the hollow fan blades which are unique to this engine model, used only on Boeing 777 aircraft.”
Former National Transportation Safety Board Chairman Jim Hall said faulty blades are only found on “the first generation” of PW4000 engines.
“I suspect the reason the planes are all being pulled is because they (the FAA and Pratt & Whitney) don’t have an inspection process in place and they’re embarrassed,” Hall told NBC News. “Over the past decade, the FAA has responded to the economic interests of the aviation industry, which has taken precedence over safety.”
Pratt & Whitney, who is owned by Raytheon, insisted he was cooperating with federal investigators.
“United Airlines Flight 328 is currently under an NTSB investigation and Pratt & Whitney has dispatched a team to work with investigators,” the company said in a statement. “Pratt & Whitney is actively coordinating with operators and regulators to support the revised inspection interval for the Pratt & Whitney PW4000 engines that power the Boeing 777s.”
But an NTSB investigation into a February 13, 2018 Pratt & Whitney engine malfunction on the United flight to Honolulu criticized the company for failing to conduct more stringent inspections.
“The lack of training led the inspector to make an incorrect assessment of an indication that resulted in a blade being returned to service with a crack where it ultimately fractured,” the report said.
Boeing said it was also cooperating with the federal government. “We believe every survey is an opportunity to learn how the industry can continue to make air travel safer for everyone,” the company said in a statement.
Feith said the Boeing 777-200s have safeguards to prevent them from crashing after this type of engine malfunction.
“The FAA requires the manufacturer of a twin-engine plane like this to certify it so that it can fly on one engine, which it has done,” Feith said.
Still, the fact that the flames took so long to go out raises troubling new questions about the safety of the PW4000 engine, he said.
“If this plane had been flying over the ocean for an hour or two, the biggest concern is that there is a fire extinguisher system on the engine and the fire continues to burn,” he said. declared.
United flight 328, to Honolulu with 231 people on board, reported problems on Saturday shortly after take off from Denver.
Video from a passenger showed one of the plane’s engines igniting and breaking up before debris began to rain on suburban Denver as the pilot signaled “mayday” to the control tower and walked away. started to turn around.
A similar scenario took place on another Boeing plane in Holland on Saturday. The pilot of the New York-bound Longtail Aviation jet, a 747-400 cargo plane powered by smaller versions of the PW4000 engines, was told by air traffic control that one of the engines was on fire shortly after its take off on Saturday from Maastricht airport.
Witnesses reported hearing at least two explosions and the plane began throwing engine parts, part of which injured a woman on the ground, airport spokeswoman Hella Hendriks told Reuters.
Dutch authorities are currently carrying out an investigation.