United Airlines and Japan have grounded their Boeing 777s powered by the same Pratt and Whitney engine, the PW4000. This comes after one of the planes suffered an engine failure over the weekend. United Flight 328, a Boeing 777-200 bound for Honolulu, made an emergency landing at Denver International Airport shortly after takeoff on Saturday afternoon after its right engine failed.
United Airlines has 52 of these aircraft on its fleet; 24 active and 28 in storage. It is the only U.S. airline with this type of engine in its fleet.
On the other hand, Japan’s aviation regulator has ordered airlines to suspend flights of aircraft with this type of engine until further notice. Japan’s Civil Aviation Bureau ordered Japan Airlines and All Nippon Airways to remove their aircraft with the same engines from service; JAL operates 14 and ANA has 19.
While the investigation is ongoing, we 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 the appropriate inspection protocol.Boeing
United operates 44 other Boeing 777s that are powered by General Electric engines.
Apart from United Airlines and Japan, Korean Air Lines also has 12 of the planes, half of them stored, and has stopped flying them to Japan for now.