MIAMI – United Airlines (UA) has just released a statement declaring it will temporarily ground 24 Boeing 777-200s powered by Pratt & Whitney PW4000s following yesterday’s incident with UA flight 328.

On Saturday afternoon, flight UA328 from Denver (DEN) to Honolulu (HNL) operated with a United 777-200 powered by PW4000s experienced severe engine issues, which forced the aircraft to return to Denver immediately. Debris from the Boeing 777’s damaged engine fell onto neighborhoods.

As a result, United Airlines has voluntarily decided to remove 24 Boeing 777-200s from service effective immediately. UA expects minimal numbers of customers to be affected by these groundings. Since the incident yesterday, the airline has been in contact with the National Transportation Safety Board (NTSB) and Federal Aviation Administration (FAA) and plans to work with them to confirm these Boeing 777s are safe to operate.

Photo: Luca Flores/Airways

Additional Responses to UA328


Other agencies are exercising caution following the incident on Saturday. Japan’s Ministry of Land, Infrastructure, Transport and Tourism recently released a NOTAM that requests airlines operating Boeing 777s with PW4000s to avoid Japanese airspace.

Additionally, the Federal Aviation Administration (FAA) will issue an Emergency Airworthiness Directive that requires immediate or increased inspections on Boeing 777s powered by PW4000s. FAA Administrator Steve Dickson states this may lead to some Boeing 777s taken out of service.

Dickson continues his statement with, “The FAA’s aviation safety experts are meeting into the evening with Pratt & Whitney and Boeing to finalize the details of the Airworthiness Directive and any accompanying service bulletins to ensure that the appropriate airplanes are included in the order. Exact details of the inspection will be specified in the emergency order.”

Photo: John Leivaditis/Airways

NTSB Releases Investigative Update


The National Transportation Safety Board (NTSB) released a preliminary investigative update for UA328 on Sunday night. According to the agency, the flight experienced a right engine failure and safely returned to Denver. None of the 229 passengers or 10 crewmembers were injured in the incident.

The NTSB’s initial report notes the majority of damage sustained was related to the number 2 engine while the aircraft itself sustained minor damage. The preliminary examination finds that the afflicted Pratt & Whitney PW4000 engine had two fractured fan blades and the inlet and cowling separated from the engine.

Jin Air’s Boeing 777s are powered by Pratt & Whitney PW4000s. Photo: Luca Flores/Airways

Boeing Recommends Grounding 777s With PW4000s


On Sunday night, Boeing released a statement regarding UA328. Specifically, the company advocates for airlines to ground their Boeing 777s powered by PW4000s. Additionally, Boeing concurs with Japan’s decision to prohibit Boeing 777s with PW4000s from flying over their airspace.

“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.”

Other carriers that operate Boeing 777s with PW4000s include Korean Air (KE), Jin Air (LJ), EgyptAir (MS), and more. Japan Airlines (JL) and All Nippon Airways (NH) have already grounded their Boeing 777s powered by PW4000s following Japan’s NOTAM.


Featured Image: United Airlines N771UA Boeing 777-222. Photo: Brandon Farris/Airways