The engine of the Pratt & Whitney plane that burst into flames and forced a United Airlines pilot to make an emergency landing shortly after taking off from Denver had similar blowouts on at least two other flights, experts said Monday.
Three years ago, a fan blade broke in one of the PW4000 engines powering another United Airlines Boeing 777-200 aircraft, this time while flying over the Pacific Ocean on a flight from San Francisco to Honolulu.
And in December, two fan blades on the same type of engine broke on a Japan Airlines Boeing 777-200 flying from Naha to Tokyo.
As in Denver, the pilots on both flights were able to safely land their planes 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 PW4000 engine malfunction.
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 Model 777-200 jets around the world as federal investigators inspect PW4000 engines in airplanes, which are used only by United. Airlines in the US and airlines in Japan and South Korea.
In particular, Federal Aviation Administration Administrator Steve Dickson said “inspections for hollow fan blades that are unique to this engine model, which are used only on Boeing 777 aircraft, are intensifying.”
Former National Transportation Safety Board Chairman Jim Hall said the faulty blades are only in “the first generation” of PW4000 engines.
“I suspect the reason all the planes are being recalled is because they (the FAA and Pratt & Whitney) don’t have any inspection process in place and they are embarrassed,” Hall told NBC News. “For the past decade, the FAA has been serving the economic interests of the aviation industry, which has taken priority over safety.”
Pratt & Whitney, which is owned by Raytheon, insisted it was cooperating with federal investigators.
“United Airlines Flight 328 is currently under investigation by the NTSB 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 Boeing 777 aircraft.”
But an NTSB investigation into a Pratt & Whitney engine malfunction on United’s flight to Honolulu on February 13, 2018, blamed the company for failing to conduct more stringent inspections.
“Lack of training resulted in the inspector making an incorrect assessment of an indication that resulted in a sheet with a crack being returned to service where it eventually fractured,” the report states.
Boeing said it was also cooperating with the feds. “We believe that each investigation 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 there are protections built into the Boeing 777-200s 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 with one engine, which it did,” Feith said.
Still, the fact that the flames took so long to extinguish raises worrying new questions about the safety of the PW4000 engine, he said.
“If this plane had been over the ocean for an hour or two, the biggest concern is that there is a fire suppression system in the engine and the fire continues to burn,” he said.
United Flight 328, bound for Honolulu with 231 people on board, reported problems Saturday shortly after taking off from Denver.
Video from a passenger showed one of the plane’s engines on fire and crumbling before debris began to rain down on the Denver suburbs when the pilot reported “mayday” to the control tower and began turning the plane.
A similar scenario unfolded Saturday on a different Boeing plane in the Netherlands. A Boeing 747-400 cargo plane, powered by smaller versions of the PW4000 engines, began ditching engine parts shortly after taking off from Maastricht Airport on Saturday.
No one was injured and the Dutch authorities are investigating the incident.