Twenty-four Boeing 777 aircraft were grounded in the US and Japan after the dramatic engine failure of United Airlines flight 328 over the weekend. The flight was scheduled to Honolulu from Denver, but the engine caught fire soon after takeoff. It safely landed at the airport and no casualties were reported.

The engine failure has raised alarm all over the world, and the investigation is being carried out by the Boeing company on its own. According to an investigation conducted by the National Transportation Safety Board, the engine failure was caused by two fractured fan blades on a section of the plane’s engine.

The Boeing 777 airplane equipped with Pratt & Whitney PW4000 engines was ordered to be inspected immediately. The Federal Aviation Administration has also issued an emergency airworthiness directive. The Boeing 777 has issued a statement to the respective airlines using planes manufactured with PW4000 engines, to ground their aircraft until further notice.

The initial investigation revealed that the hollow fan blades of this unique model of the engine need to be stepped up for inspection. The FAA has sent the directive to the airlines using PW4000 engines to start an inspection on an immediate basis.

Meanwhile, United Airlines has voluntarily grounded their 24 Boeing 777 aircraft.

Japan’s Civil Aviation Bureau has also announced that all the aircraft using the PW400 engines will be removed from the service till further notice. It is to be noted that Japan Airlines and All Nippon Airways use Boeing 777 aircraft.

This whole frenzy over Boeing 777 started over the weekend when the United Airlines flight 328 had an engine failure right after the takeoff. The aircraft made a safe landing after the pilots made a “mayday” call to the air traffic control. No one was injured among the 231 passengers and 12 staff of the airline.

The incident was caught on camera and the passengers uploaded videos of the affected engine.