B777 grounding

[tsumini]

Dan,
I preume your B777 GE powered not P&W4000.
Looks like P&W is history on airliners except for the Geared TorboFan on Airbus

[94touring]

Rolls-Royce Trent 800s.  They sound cool too.  I'm actually in the American Airlines 777 sims we lease out doing engine failures tonight.  I'd be surprised if they mothballed the Pratts over a couple recent engine failures.  These things happen on all engines more than the public probably knows.  Non engine related but 767s for example are known to crunch the fuselage on hard landings.  So much so boeing comes out, cuts the plane in half, removes the old section, puts in a new section, and 3 weeks later that bent up can is in the air again.  Oh and metal fatigue on gear unexpectedly?  Here's one of ours this past year.

[MiniDave]

Where was that? I'm noticing the homes right next to the runway.....

[94touring]

Bucharest Romania.

[tsumini]

Except too much bad press can destroy a program for some of the most benign problems. This video will be on perpetual loop whenever "fan blade" is mentioned.
i used to Rep for Pratt so am aware of the things we take for granted will become media fodder.
I haven't followed the B777 closely but understand it's one of the most popular wide bodies left and wouldn't be surprised to see UAL retire Pratt powered AC to third world.

Gear collapse, Hydrogen embrittlement?

[94touring]

It's possible they retire them, but I'd say only due to lack of demand since the long haul passenger flying has been halted for a year now due to covid.  This engine stuff is great for clicks and headlines but unless they lawn dart a couple of them and kill 800 people, I don't see much coming out of this other than some inspections on fan blades.  The pratt blades are hollow the one guy I was flying with last night was saying.  They run the bleed air through them for anti-ice or something so he thought.  Delta retired their 777's this year and those planes were young.  American had about 100 widebodies parked in Tulsa for much of the year.  It's a ghost town in their sims that's for sure.  I think Boeing has cut production of the 777X's in half due to demand.  If this was the last plane I flew the rest of my career I'd be happy.  It's a beast and easy to fly.  Southwest went through a phase of having cracks in fuselages that made some headlines but again they just upped inspections.  Then a couple years ago they had a couple engines grenade, one shooting shrapnel inside and sucking a lady out the window killing her.  Even that blew over pretty quickly.  The 787's were grounded for I want to say a couple months early on when they had their batteries catching fire while I'm thinking of it.  The 737max stuff I won't even bother getting into.  I'm glad they're finally flying again.  Also glad I bought all that boeing stock at rock bottom prices!

Not exactly sure what they determined on the gear other than metal fatigue.  I know it was something they had recently inspected and it was no fault of our maintenance or crew.  They had it fixed up pretty quick and back flying again.  That particular plane does some "interesting" flying and is a pretty big cash cow.         

[tsumini]

Yeah guess you're right; it doesn't count if there's no body count. The mantra of the Vietnam era.
Like I said I haven't kept up with the industry much. From the results of the UAL 2018 inspection debacle of overlooking
a material flaw I think the hollow blade is a necessity for saving weight. Rotating airfoils just don't ice up. Just like a wing it
would be too heavy if solid metal even titanium. They are huge paddles and fan hubs couldn't handle solid wide chord blades.
Unfortunately fatal flaws can be hiding.
Like you alluded to, problems can  be solved with diligence and common sense.
BTW, I wasn't brave enough for Boeing stock. I dabbled a little in Bitcoin.

[94touring]

Well I've had fan blade ice in smaller jets and it sucks big time if you're not familiar with it.  First time both engines iced up and shook the plane something horrible, audibly making popping noises, and the vibration gauges going crazy.  QRH said shut the engine down.  Well that's kind of difficult to do if they're both doing it.  That scenario was caused by a windshield wiper blade, let me explain!  Wiper blade was written up for being out of parked and was approximately 4 inches onto the windscreen.  I opened the escape hatch, poured water on the windscreen, cycled the wiper, and it parked.  I called maintenance and said let's take this off the MEL list.  They said it requires lots of testing and it would be 2 hours before anyone could get to it.  The MEL because the max wiper speed is 220 knots as a limitation had the max speed of the flight at 220 knots.  That's a snails pace and legally I couldn't go faster as dumb as it sounds.  Ok so off to Savanah Georgia from Philadelphia I go at 27000 feet in the winter.  Get to altitude, fly into icing conditions, turn on the engine heat to prevent ice build up, and we're simply going too slow for the engines to shed ice even with the heat on.  Give the thrust levers burst of power to increase fan blade speed to break up the ice but the speed of 220 is just too slow.  Book says shut the engines down.  I say the hell with this, start a decent, get up to 330 knots indicated, and the ice breaks off.  Next flight was to Toronto and I refused the plane for above reasons.  Next time was over the great lakes flying into Chicago during the winter on an arrival.  Ice is notoriously bad there and builds up thick and fast.  Engines kept getting it but would shed it off when I'd power up to increase fan speed.  Engine heat should prevent it but not always.  Another pilot was in the back and after we landed asked if that's what it was.  So he knew something was wrong cause it sounds and feels bad. 

[jeff10049]

Ice on the propeller of small planes sucks and it can happen in conditions when you wouldn't think of icing.  And rpm doesn't help much changing altitude is the best option and hope it goes away.

Dan, As I was reading your post I was thinking about the 737 and commenting then before I got to your I won't bother getting into it I thought the same. The media and people's minds are made up don't bother them with facts.

[tsumini]

Yeah airplane icing sucks for sure.

I occasionally pop into a forum called PPRUNE.org (Professional Pilots Rumor Network) to hear opinions etc of newsmakers such as the subject incident. It will have some interesting and usually immediate info. But it never ceases to amaze how people think and react. Seems like the most talked about subject was whether the failure was a "contained" failure or "uncontained".

[94touring]

I think it put a big gash in the fuselage from what I've heard, so I'd say uncontained if that's the case.

[94touring]

Here's a couple photos showing the missing blade, with another blade getting broken, as well as the gash in the fuselage.  Luckily hit down there and didn't fling up into the cabin.   

[cstudep]

Yeah that's a pretty good sized hole

[94touring]

Well you figure the fan diameter is over 9 feet long, at least on the one I fly.  That's a big piece of metal.  Total engine weight about 13,500lbs and produces up to 92,900 foot pounds of thrust.  It's a big ass airplane!  Ferrying back empty from Europe I get up and walk laps around the cabin to stretch my legs, 4 laps is about a quarter mile.

[cstudep]

That is a great illustration of scale, that is a huge plane for sure! All in all I would say that while the failure may have technically been "uncontained" it appears the nacelle did a decent enough job keeping potential damage to the fuselage to a minimum. Of course a lot of that probably depends on just where exactly in the rotation cycle the thing started coming apart.

[tsumini]

I think it put a big gash in the fuselage from what I've heard, so I'd say uncontained if that's the case.

My guess is that investigation will show that the failed blade airfoil impacted the fan Case was contained and exited thru the fan duct and out the rear. I'm thinking the engine cowling got whipsawed by vibration into the fairing at wing root.
NTSB also surprised by saying there was evidence of metal fatigue on the blade. Usually they wait for laboratory report especially for low cycle fatigue.