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RandomPerson8008
21st Apr 2021, 18:50
I'm wondering if anyone has a rough estimate of the B-747's angle of incidence (the -400 and/or -8, or even the classic).

I realize the wing has washout and therefore the incidence angle is not constant, but something close to an average angle would be interesting to know.

Thanks.

DaveReidUK
21st Apr 2021, 21:10
By convention, incidence is normally defined as that at the wing root.

The 747's is 2.0°. I don't know what the value is outboard.

Intruder
21st Apr 2021, 21:25
Easily found in a quick search of "747 wing angle of incidence" (9th entry):

https://www.quora.com/What-is-the-angle-of-the-plane%E2%80%99s-wings-when-cruising-at-35-000-feet?share=1


RandomPerson8008
24th Apr 2021, 17:00
Ok, thanks DR and JW.

The topic came up in a debate about how close to AOA that the aircraft's pitch attitude minus flight path vector is. Someone pointed out that (pitch attitude + angle of incidence) - flight path vector would be close to an actual AOA value, but we were unsure how wing washout etc would affect the AOA value. I guess it is not so simple on a big, complex wing, which is why we are taught that pitch attitude - flight path vector is an "indirect indication" of AOA.

Apologies for not finding it on my own searches. I guess my error was omitting the term "wing". Simply searching for "747 angle of incidence" was insufficient.