Boeing has suspended operations on more than 120 777 aircraft powered by Pratt & Whitney 4000-112 engines after an incident on board a United Airlines flight.
Had a front row seat to the entire engine failure on United flight 328. Kinda traumatized to fly United more. #UnitedAirlines pic.twitter.com/5KdJn1BGfV
— Chad Schnell (@ChadSchnell) February 20, 2021
On Saturday, February 20th, United flight F328 from Denver to Honolulu had to return to Denver International Airport for an emergency landing following a dramatic engine failure. Alongside flames from inside the engine, the inlet and cowling of the Pratt & Whitney PW4077 on the right wing also detached, scattering debris around the Broomfield area to the west of the airport. None of the 229 passengers or 10 crewmembers were injured.
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According to a preliminary investigation from the US’s National Transportation Safety Board (NTSB), most of the damage was confined to the number two engine, with minor damage sustained to the aircraft itself. Two engine fan blades were fractured, one near the root and an adjacent blade in about mid-span. A portion of one blade was imbedded in the containment ring, while the remainder of the fan blades exhibited damage to their tips and leading edges.
Flight UA328 from Denver to Honolulu experienced an engine failure shortly after departure, returned safely to Denver and was met by emergency crews as a precaution. There are no reported injuries onboard. We are in contact with the FAA, NTSB and local law enforcement.
— United Airlines (@united) February 20, 2021
NTSB investigators will continue to examine the engine and aircraft, as well as photographs and video taken by passengers aboard the flight. The cockpit voice recorder and flight data recorder were also transported to the NTSB laboratory in Washington for analysis. A statement from the Federal Aviation Administration (FAA) said the agency was recommending “stepped up inspections” of all Boeing 777s flying with certain types of Pratt & Whitney PW 4000 engines.
“We reviewed all available safety data following yesterday’s incident,” said FAA administrator, Steve Dickson. “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. This will likely mean that some airplanes will be removed from service.”
United 328 photo reveals engine fragments caused damage to the aircraft's fuselage. pic.twitter.com/Gd3wfES3kY
— Breaking Aviation News & Videos (@breakingavnews) February 22, 2021
United Airlines said it was temporarily grounding all 24 of its Boeing 777s on active duty, with the Japan Civil Aviation Bureau also taking action on its affected aircraft, and Boeing itself recommending suspension of flights on the 69 in-service and 59 in-storage 777s powered by Pratt & Whitney 4000-112 engines.
“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,” the company said in a statement.
“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.”
In the first video taken by the passenger the engine is rotating and is clearly on fire. Was the engine still ‘on’?
Did the take off weight mean that the pilot was unable to fly the plane with just one engine and needed at least some power from this engine? If it was shut down why was it still on fire? (there isn’t very much in an engine to burn once the fuel is cut off).
The picture of the engine on the ground clearly shows half of one of the fan blades is missing, this probably caused the damaged to the fuselage, amazing it didnt wreck the whole fan.
And another failure ! same day ! same engine:
https://www.theguardian.com/business/2021/feb/22/dutch-investigate-boeing-747-after-engine-parts-drop-after-takeoff-netherlands
In response to Ekij.
May have been the contents of LO burning out (perhaps in the region of 175 L of oil, please correct if wrong).
Could they have jettisoned the engine if things got too hot, are they fitted with explosive bolts?
Was a very steady hand on that camera!
I suspect that the visible rotation would be caused by the airflow over/through the remaining fan blades.
A fuel line may have been severed when the blade detached, possibly causing a small amount of leakage despite the cut-off. Of-course this is only speculation.
Captain Joe on Youtube has quite a good analysis of this, worth a watch.
https://www.youtube.com/watch?v=q5Wler87pwY
The text in the post mentioned hollow fan blade, is this to reduce weight or cost or both? I thought fan blades were solid metal. Were the hollow fan blades the cause of the near disaster? Not flying for a long time anyway!! Long live the train and boat.
Lubricating oil burns, air flow is causing the turbine to turn (windmill like a propeller), oil pump is aux drive shaft off the turbine shaft therefore oil pump is turning. May not be enough for proper lubrication but enough to feed small fire. Engine is off. Oil pump is positive displacement pump, if it moves it pumps some.
The investigations will be very informative.
My first reactions were: “Glad I was not on that flight”, then, “The failure mode design was excellent and the aeroplane landed safely, air transport remains extremely safe, if not always smooth!”
Didn’t the containment fail to protect the fuselage?
Graham