The airline stops flying 24 planes after an engine burst into flames soon after take-off from Denver.
United Airlines says it is grounding 24 of its Boeing 777 aircraft after one of its jets suffered engine failure after take-off on Saturday.
The plane, carrying 231 passengers and 10 crew, was forced to return to Denver airport. No injuries were reported.
Debris from the jet was found scattered over a nearby residential area.
In response to the incident, Japan has asked all airlines using Boeing 777s with the same Pratt & Whitney 4000 engine to avoid its airspace.
Boeing said it supported Japan’s decision and has recommended suspending operations of all 777s with the same engine while an investigation into the incident continues. The manufacturer says there are 69 Boeing 777s currently in service worldwide with this engine.
According to the Federal Aviation Administration (FAA), United is the only US airline flying such planes, with the others being in Japan and South Korea.
United Flight 328, bound for Honolulu, suffered a failure in its right-hand engine, the FAA said.
The agency has ordered extra inspections of Boeing 777 jets fitted with the Pratt & Whitney 4000 engine following the incident.
“We reviewed all available safety data following yesterday’s incident,” said FAA administrator Steve Dickson in a statement.
“Based on the initial information, we concluded that the inspection interval should be stepped up for the hollow fan blades that are unique to this model of engine, used solely on Boeing 777 airplanes.”
The FAA is meeting representatives from the engine firm and Boeing.
The National Transportation Safety Board’s initial finding is that most of the damage occurred in the right engine, where two fan blades were fractured and other blades also impacted. The main body of the aeroplane suffered only minor damage.
Passengers onboard the flight described a “large explosion” shortly after take-off.
“The plane started shaking violently, and we lost altitude and we started going down,” David Delucia said.
He added that he and his wife placed their wallets in their pockets so that “in case we did go down, we could be ID’d”.
Police in the town of Broomfield posted pictures of what appeared to be the front of an engine casing in the front garden of a home. Other fragments were seen around the town including on a football field. No one was injured by the falling debris from the plane.
In Japan, all 777s with the Pratt & Whitney 4000 model engines are to avoid its airspace until further notice. This includes take-offs, landings and flights over the country.
The government there has also ordered JAL and ANA airlines to suspend the use of its 777s with the same Pratt and Whitney 4000 model engine.
Last December a JAL flight was forced to return to Naha Airport due to a malfunction in the left engine – the plane is the same age as the 26-year-old United Airlines plane from Saturday’s incident.
In 2018, the right engine of a United Airlines plane broke shortly before it landed in Honolulu. Following an investigation, the National Transportation Safety Board said the incident was caused by a full-length fan blade fracture.