UA1175 emergency landing Honolulu

[rog747]

Hokulea

goodness that vibration is something - thankfully occurred near the end of the flight and HNL was nearby - i would not want to be on that for any longer than ness to get down to the ground PDQ
had it happened halfway across the pacific with 2-3 (ETOPS) hours of flying time it would have been awful for the pax & crew

[tprop]

Looks like the camera is shaking a lot more than the engine.

[Hokulea]

I wouldn't be suprised if the camera was shaking. Vibrations in the airframe and the photographer being a bit scared might do that. But compare the engine with the side of the window frame. The engine was vibrating significantly.

[stilton]

Originally Posted by BRE

Is that so?

My understanding is that in both cases, for the V2 scenario, a single engine out is considered. This means that a 4-holer must be able to climb out safely on three engines, whereas a twin must on one. Hence one engine on a twin has considerably more thrust reserves than two on a quad.

Apples and oranges, you’re describing a completely
different situation, engine failure on departure in a twin
nearly always mandates an immediate return with a possible
exception of weather minimums being adequate for departure
but not a return in which case you’re going to your
departure alternate

And yes, of course performance on one in
that case will be better than a four engine aircraft that
has lost two

I was referring to the en-route phase, a long way from
land or over hostile terrain I’d be far happier in a B707
that has lost two than ANY twin that is down to one
operating engine

[mustafagander]

It must also be kept in mind that the gradients required to satisfy the T/O climb segments are significantly less for twins than for quads.

[stagger]

Originally Posted by stilton

I was referring to the en-route phase, a long way from
land or over hostile terrain I’d be far happier in a B707
that has lost two than ANY twin that is down to one
operating engine

Can a 707 stay airborne on 1 engine? If not then in both cases - either with the 707 flying on 2 engines or the twin flying on 1 engine - you are still just 1 engine failure from getting wet.

And even putting aside differences in engine reliability between old turbojets and modern turbofans - you've got double the chance of having that further engine failure in the 707.

[lomapaseo]

It's a little worse than that when you consider your chance of a any engine failure on a quad is increased, then after that you have more combinations etc.

But it all fades to nil when you consider the chance of you being on a long-haul B707 today are extremely low

[Heathrow Harry]

"The cowls are secured by a number of latches. Given the sophistication of the systems to ensure cowls do not open and become detached in flight, what would have caused such an occurrence?"

this must be different from the Delta 777 I was on at LHR last year when the guys trying to close & lock the cowling appeared to be using a hammer, a small screwdriver and a Swiss Army Knife - and lots of sweat.

[Volume]

We are not talking about the cowl doors here, but about the fixed inlet cowl which is bolted to the fan case with probably 100 bolts. This can not be opened and has no latches. Once this part is missing, air flows under the cowl doors and breaks them, irrespective of the latches.
The big question is: Did the nose cowl fail and was partly ingested, damaging the fan, or did a fan blade fail and destroy the noce cowl ? Not easy to tell from the pictures.
As there is no debris visible behind the fan, I tend to believe in the second scenario, but this is just an educated guess.

[Zeffy]

Associated Press quotes NTSB.

Broken fan blade cited in United jet’s engine failure

https://www.seattletimes.com/busines...ngine-failure/