The Federal Aviation Administration is ordering inspections of all United Airlines’ Boeing 777s equipped with same engine type which burst into flames over Denver on Saturday.

United has said it will be temporarily removing aircraft using the same Pratt & Whitney PW4000 engines from service. The announcement came after United Airlines Flight 328 made an emergency landing at Denver International Airport after its right engine blew apart just after take-off.

Debris from the blast, including engine casings landed within a suburban areas. The plane had 231 passengers and 10 crew on board and landed safely. There were injuries to passengers or to those on the ground, according to US aviation regulators.

FAA administrator Steve Dickson said that based on an initial review of safety data, inspectors “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”.

United is only airline with PW4000 in fleet

United is the only US airline with the Pratt & Whitney PW4000 in its fleet and currently has 24 of the 777s in service.

The National Transportation Safety Board (NTSB) added that two of the engine’s fan blades were fractured and the remainder of the fan blades “exhibited damage” but cautioned that it was too early to draw conclusions about the incident.

A video posted on Twitter showed the engine fully engulfed in flames as the plane flew through the air. Freeze frames from another passenger video appeared to show a broken fan blade in the engine.

Boeing supports suspension of B777 powered by PW4000

A statement issued by Boeing read: “Boeing is actively monitoring recent events related to United Airlines Flight 328. While the NTSB 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 FAA identifies the appropriate inspection protocol.

“Boeing supports the decision yesterday by the Japan Civil Aviation Bureau, and the FAA’s action today to suspend operations of 777 aircraft powered by Pratt & Whitney 4000-112 engines. We are working with these regulators as they take actions while these planes are on the ground and further inspections are conducted by Pratt & Whitney.

“Updates will be provided as more information becomes available.”

United said it would work closely with the FAA and the NTSB “to determine any additional steps that are needed to ensure these aircraft meet our rigorous safety standards and can return to service”.

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