United Airlines is currently facing significant operational challenges due to engine issues affecting its Boeing 777 fleet. The airline operates 74 Boeing 777-200 aircraft, with an average age of approximately 26.5 years, making it one of the oldest widebody fleets in operation. Recently, only 64 of these aircraft are actively flying, after 10 were parked as a result of ongoing problems.
The core issue revolves around the Pratt & Whitney PW4000 engines, which power the airline’s 777s. The situation worsened after a 2021 incident involving Flight UA328, which experienced an engine failure shortly after departure from Denver. Investigations by the FAA and NTSB revealed concerns about metal fatigue, leading to the temporary grounding of the entire PW4000-powered 777-200 fleet. This incident has had lasting effects, with ongoing engine availability and supply chain challenges complicating the airline's capacity management.
Impact and Outlook
United Airlines has been relying more heavily on alternative aircraft such as the Boeing 767 and the Boeing 787 to compensate for grounded jets. The arrival of new Boeing 787 aircraft, expected to stabilize deliveries in 2026, is anticipated to help alleviate some of the capacity limitations caused by the old fleet and engine shortages.
The airline’s reliance on older aircraft has also been compounded by production and supply chain disruptions affecting Boeing’s newer aircraft, especially the 787 family. Despite these setbacks, United expects that the integration of newer planes will eventually restore capacity and improve operational resilience in the coming years.
