United 328

a reply to: Flyingclaydisk

They were routed around the airport while running checklists. They came in on 26.

It appears cowling is a specific term and fairing is more generalized? I had always thought fairing was the correct term but cowling seems to be specific to engines. When you have the time would you mind enlightening me? Or is it just down to semantics? I just always thought most drag reducing enclosures were fairings regardless of what they surrounded. I'm curious as to your thoughts on the matter but I understand if you lack the time or interest to elaborate.

originally posted by: Flyingclaydisk
Okay...well, I'm done.

I gave y'all everything I know.

Enjoy your night.

a reply to: Zaphod58

Yeah, not surprised; that's what's been open a lot lately. Lot's of construction now, I haven't kept track.

ETA...Plus, less to wreck off to the east!

a reply to: Morbidlynx

Zaphod will be glad to illuminate any inconsistencies I have spoken.

He's on the case now.

a reply to: Morbidlynx

The ring cowling is the front portion of the engine. The cowling is what opens to work on the engine. A fairing is used to cover gaps and reduce drag.

originally posted by: Zaphod58
a reply to: Morbidlynx

The ring cowling is the front portion of the engine. The cowling is what opens to work on the engine. A fairing is used to cover gaps and reduce drag.

The curious thing here is that the cowling forward of the fan is gone, but the fan is obviously still there and windmilling (although out of balance). I'm wondering if the tips of the fan blades contacted the inside of the cowling and basically torqued the cowling off (a spiral fracture kind of thing)?

Keep in mind I'm watching a low quality Facebook video, the fan appears intact. This was an uncontained failure of either the LPT or HPT. My money is on the LPT failing, and going out through the inlet cowling, and causing damage that ripped it apart, causing the rest of the cowling to separate.

a reply to: 1947boomer

I'm betting the one of the LPT blades separated and went through the inlet, and aerodynamic pressure ripped it off.

originally posted by: Zaphod58
a reply to: 1947boomer

I'm betting the one of the LPT blades separated and went through the inlet, and aerodynamic pressure ripped it off.

If the LPT shed a blade that would cause the fan to be out of balance, would it not?

a reply to: 1947boomer

The out of balance condition would depend on which LPT compressor shed the blade. If one of the forward blades went, it would probably cause an unbalance. If one of the back blades went, it probably wouldn't as much, because the turbines ahead of it would help to absorb the unbalanced condition. It looks like the fan is just windmilling though, so it's hard to tell if it's unbalanced or not. SOMETHING in that engine is unbalanced though, the way it's wobbling like that.

a reply to: Zaphod58

Whatever caused the imbalance, that would explain why the the leading edge of the cowl was severed cleanly and as a unit, which is what was reported by the guy on whose truck the cowl fell. Also, it was accompanied by a shower of fiberglass fibers. Looks like the fan basically sawed off the leading edge of the cowling.

After that, aerodynamic forces would have ripped off the rest of the cowling.

originally posted by: Bluntone22
A guy found some stuff in his yard.

Finders keepers, that friggin thing would be a yard ornament, United can go buy a new one. This one is mine now LOL

Awesome, thank you for the explanation. I appreciate your time. Despite being really into aircraft and space flight the difference isn't often obvious or well explained.

originally posted by: Zaphod58
a reply to: Morbidlynx

The ring cowling is the front portion of the engine. The cowling is what opens to work on the engine. A fairing is used to cover gaps and reduce drag.

a reply to: Zaphod58
Do we know which engine was in this aircraft? P&W?, GE?, RR?

a reply to: 1947boomer

United uses the PW4000 on their Triples.

a reply to: 1947boomer

That's why I say LPT. Whatever it was has to have damaged the inlet, otherwise it wouldn't have come off like that. That means it has to have been near the fan. The fan appears intact, so it doesn't look like a fan blade.

So, interesting bit of trivia, on Feb 13, 2018 United 1175 going from San Francisco to Honolulu threw a blade through the cowling, and had the #2 engine come apart shortly before landing. That was N773UA. Yesterday was N772UA.

That will buff out. No problem.

a reply to: Bluntone22

I thought this was SHANKSVILLE at first.