Japan has grounded Boeing 777 jets, while the US will subject some to extra inspections after one showered debris over an American town after an engine caught fire in a frightening episode.

The Honolulu-bound Boeing jet scattered debris over a residential area near Denver, Colorado, on Saturday (local time) as some terrified passengers held hands and prayed amid fears they were about to die while the engine burned outside their plane windows.

The United Airlines flight, with 231 passengers and 10 crew aboard, landed safely in Denver after its right engine failed.

Dramatic images showed debris from the plane scattered on the ground and its engine in flames as it failed soon after the Boeing 777-200 had taken off.

“The plane started shaking violently, and we lost altitude and we started going down,” passenger David Delucia said.

“I thought we were done. I thought we were going down.”

Mr Delucia and his wife stuffed their wallets into the pockets so they could be easily identified if the plane did crash.

But it didn’t. And there were no reports of injuries, either on the plane or the ground.

“The pilot did an amazing job. It was pretty unnerving,” Mr Delucia said.

United said on Sunday it would voluntarily and temporarily remove its 24 active planes of the type from its schedule.

The US National Transportation Safety Board said it would inspect planes with the affected Pratt & Whitney 4000 engines.

Japan’s transport ministry went further, ordering Japan Airlines and ANA Holdings to suspend the use of 777s with P&W4000 engines while it considered additional measures, according to Reuters.

The ministry also reported another incident involving one of the planes. It said a Japan Airlines flight from Naha Airport to Tokyo International Airport on December 4, 2020, returned to Naha after an engine malfunction about 100 kilometres from the airport.

That plane was the same age as the 26-year-old United Airlines plane involved in Saturday’s incident.

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Images posted by police in Broomfield, Colorado, showed significant debris on the ground after the frightening engine failure. They included an engine cowling outside a home and what appeared to be other parts scattered across a paddock.

One video taken from what appeared to be inside the United plane showed an engine on fire.

Another video on social media showed a cloud of black smoke being left by a plane.

“Something blew up,” a man on the video can be heard saying.

In an audio recording, a United pilot can be heard making a mayday call to air traffic control at Denver International Airport.

“Mayday, aircraft just experienced engine failure, need to turn immediately,” according to audio from the monitoring website liveatc.net.

The Federal Aviation Administration said it and the NTSB would investigate. Investigators will focus on what caused the accident and will look at whether a fan blade failed.

“If you find debris PLEASE don’t touch it or move it. The @NTSB wants all debris to remain in place for investigation,” Broomfield police said on Twitter.

The engine cowling landed in a front yard in Broomfield, near Denver. Photo: AAP

Boeing said its technical advisers would assist the NTSB, while United also pledged to work with US federal agencies.

United said most of the passengers on the affected flight took off on a new flight to Honululu late on Saturday.

Engine failures are rare but are potentially dangerous whenever rotating parts pierce the outer casing – an event known as an uncontained engine failure.

In February 2018, an older Boeing 777 operated by United and bound for Honolulu suffered an engine failure when a cowling fell off about 30 minutes before the plane landed safely.

The NTSB determined that incident was the result of a full-length fan blade fracture.

Because of the United fan blade separation incident, Pratt & Whitney reviewed inspection records for all previously inspected PW4000 fan blades, the NTSB said.

In March 2019, the FAA issued a directive requiring initial and recurring inspections of the fan blades on the PW4000 engines.

-with AAP