FAA - Emergency Airworthiness Directive for Boeing 777 with PW4000 engines

That would be PW4000-112. It's the largest commercial PW engine. It has 112 inch, shroudless, hollow titanium fan blades,

Not the first time either

http://aerossurance.com/safety-management/ndi-failures-b777-...

https://www.flightglobal.com/safety/united-777-blade-failure...

>US investigators believe prolonged absence of formal training and certification for a fan-blade inspection technique resulted in a flawed blade being returned to service and subsequently fracturing on a United Airlines Boeing 777-200.

>The fracture in the right-hand Pratt & Whitney PW4000 fan blade, during cruise at 36,000ft on 13 February 2018, led to the loss of most of the inlet duct and all of the left and right fan cowls.

>It also resulted in debris – believed to be from a blade – puncturing the right-hand side of the fuselage, just below the window line.