JB, today a UAL flight B777 had to return to SYD. Apparently one of its engines swallowed a bird.
Must've been a flock of pelicans, given how large those engines are.
We're relying on the media and of course, the eye witness reports from the pax themselves, so who knows what really happened?
It could well have been multiple birds.
But let's assume that whatever it ingested that it caused a compressor surge and a resultant flame out. I'm guessing that as it's what you guys might call an ETOPS flight that they played it safe and returned to Sydney to get the engine checked out.
I doubt that the engine flamed out, or for that matter, even compressor stalled. A change in the engine note, or an increase in the vibration level would get your attention. I don't think the 787 uses bleed air, so you'd not be able to rely on that burnt chicken smell.
It's a big ocean...you don't set out over it with any doubt about the machinery.
Which brings me to my question of the day: how many such events, not necessarily involving FOD, have you experienced? How do modern jet engines handle compressor surges or stalls?
Compressor stalls are very rare. I've seen them a couple of times. The engines on the 767-200s would occasionally stall during start. You'd probably hear it, but the temperature running away was the big clue. I recall a couple on the 747 Classics, but only in reverse. And we couldn't even identify which engine had done it, as it recovered as soon as reverse was cancelled. The flash of flame on one night landing in Bahrain was quite spectacular, but only served to tell us it was 3 or 4.
I fed an entire flock of birds through a CF6 out of Perth. The vibration level rose quite a bit, and the engine sounded different. We ran it at idle, did a circuit and landed. Engineers counted 12 strikes. Four fan blades bent, two fan stator blades missing. A hole punched into the casing, and one of the flap fairings was missing entirely. Took them about 4 hours to fix it. Nevertheless, not only did it continue running, but actually would have been capable of almost full power.
I'd imagine that being on a climb out and to hear or feel something like that happen may be a tad unnerving. Which would give rise to the saying, "I'd rather be down here wishing that I was up there, than being up here and wishing that I was down there" feelings from the nervous...
I've never had one stall at high power. The simulator version is very noisy and very rough....I assume it's reasonably accurate.
