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United pushes back the return of dozens of Boeing 777 jets until at least May 13
United Airlines doesn't expect to fly dozens of Boeing 777 jets, grounded more than a year ago after one suffered an engine failure, until at least mid-May. The airline had most recently planned for at least some of the planes to return to service this month. United's Pratt & Whitney-powered 777s were taken out of service after an engine failure shortly after takeoff from Denver in early 2021. United Airlines doesn't expect to fly dozens of Boeing 777 jets, grounded more than… (www.msn.com) 기타...Sort type: [Top] [Newest]
who needs 2 engines when you can fly with one :-) What could possibly go wrong here.?
I applaud United. They are making sure the Jets are safe before they return them to duty and that is what aviation needs right now. Safety.
Well that’s your opinion. fair enough. I personally don’t know what specifically triggered the delay. Other groups outside of United might have exercised influence. To say wait-a-while before return-to-service Such as FAA, Pratt, pilots union? Maybe the recent set of PW 4060 failures is prompting a review of other systemic reliability issues?
As an old Materials Engineer with 50 plus years NDT experience a lot having to do with turbine failures, I said some time ago that the push to design larger and larger engines while cutting materials tolerances, especially on rotating parts in order to achieve better fuel economy would lead to more inflight failures, it looks good on paper, but stress is stress and metal fatigue is ever present in the operating environment
Ken, yes materials cumulative stress / cycles are at the heart of the matter. These titanium fan blades were touted as state-of-the art when introduced around year 1995. AFAIK, the specific engine type 4077 has not been in production for quite some while. A poster at a different website suggested an Internet search term for Cold Dwell Fatigue. From October 2021. it discusses life-limiting factors in aircraft engine titanium alloys.
Boeing has been going through a lot of bad situations in the last few years and it seems there is not going to be a quick solution for them. The Airline industry has a long memory which also won't help.