Boeing 787 AOA too high?

I’m curious about the entire Boeing 787; it seems the aoa (angle of attack) is way above 3 degrees which looks like, if true in real life, would cause passengers and flight attendance serving food to roll all the way back from the angle, kind of like falling towards the back. I find it very annoying which is why I avoid flying it. Is this normal for the Boeing 787 family? Curious

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All aircraft at cruising altitude have 2-3 degrees of attack angle in real life

I have thought this as well. I have a hard time believing the aoa is that high in real life.

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It’s so interesting how the Boeing 777 family, the Airbus A330, and 350 looks like it’s around 2 degrees aoa even at 41,000ft altitude. But regardless if I even have 10 people in the Boeing 787, it looks like it’s one turbulence from stalling lol

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The aoa is fundamental to generating lift and varies depending on weight and IAS.

The heavier you are the more lift you need, so the higher your aoa will be to offset weight to remain in level flight.

The lower your IAS, the higher your aoa will be also be to make enough lift to offset weight.

If you are heavy and slow you will need noticeably more aoa.

You can continue your step climb to higher altitudes as long as you can fly with fast enough TAS to give you sufficient IAS to keep your aoa within reasonable limits (for the weight you are carrying).

IAS represents dynamic pressure available for the wings, which of course varies increasingly from TAS as you go higher.

edit:
I just tried a short test of the 787 as shown below. Notice how the AoA varied even though TAS (mach 0.82) was always the same. I had to have an AoA of 4 at 35,000 feet with the IAS being down at 260kts. If I was lighter at that altitude and speed my AoA went down to 3.

But only by being down at 28,000 could I get enough IAS to reduce my AoA to 2 (the step climb issue comes up).

787

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Thank you so much for this information :)

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Thank you so much for this information 🙂

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The 787 (at least in IF, presumably IRL as well) cruises with a higher angle of attack when compared to other widebody aircraft. It is prefectly normal to have 4-5 degrees above the horizon at cruise, especially if you are heavy and/or crusing higher up. (I’ve hit FL430 with them in IF, you can get 5-6° above the horizon).

There are lots of factors that affect AoA at cruise (speed, altitude, weight & balance, center or gravity, air temperature, density, pressure, to name a few)

As long as you are at an appropriate altitude for your aircraft load and crusiing at M.84-M.85, your AoA is perfectly acceptable

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I’d agree that AoA is affected by speed, altitude, weight, air temperature (to the extent it changes density), density itself (as it affects IAS), and pressure (same as density).

But, unless I’m mistaken, AoA is not affected by balance of load and the resultant center of gravity. Nor is it affected in any way by winds.

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Oop you’re right, my bad. Winds don’t affect it

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But also the balance of load relative to CG, while it affects trim requirements, does not affect AoA.

Load and CG can have a slight impact on AoA

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The movement in trim also means the amount of lift needed to maintain cruise altitude changes a bit as well. (It seems mimimal, but that’s why I included it as a factor)

That’s very cool. Thanks for that. That didn’t come to mind.

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Full article about AoA here, quite an interesting read imo

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Thanks, I’ll definitely check it out.

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Here’s the simple answer, it needs a rework.

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Here’s an image from a youtube video of the 787 in flight from the cockpit. If you look at the line it seems like it’s pitched up 2-3 degrees so yeah it is realistic and does happen! If your saying it’s above 2-3 degrees then are you sure your at Mach 0.85 which is its cruising speed above FL350?

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Yes, usually I even cruise at Mach .87 at 34000 ft with about 80% load to see what happens and the aoa is at 4 degrees. But based on the image you’re showing if it’s normal then I’ll accept that. I never flown it in real life so I was imagining unless cabin pressurization make it feel like it’s even during flight, it looks like everyone is climbing their way up towards the front when going to the lavatory, FA serving meals, etc.

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Yes I agree it needs a complete rework