I think I understand how airplane wings create lift when taking off, but I can’t wrap my head around how they stay in the air once they reach cruising altitude.
My understanding of how wings work during takeoff is: by changing the wing’s angle of attack, air molecules under the wing are deflected down, in turn creating lift on the wing. And air molecules that go over the wing are not met with that resistance from the wing, so they move faster than the molecules underneath, creating a pressure difference which also helps generate lift.
But when the airplane reaches cruising altitude, the wings seem pretty much horizontal, so it seems the angle of attack is not nearly as large as it was during takeoff. So at that point how do the wings generate enough lift to stay in the air?
Thank you
Edit: I’m studying mechanical engineering and have taken a fluid mechanics class so I have a little bit of background knowledge, but am still having a hard time understanding this
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Aircraft mechanic here.
The wings are still pitched up a bit. There’s no magic.
The plane is design to have the wings at an efficient angle in cruise, the wings are slightly pitch up compared to the flight path, and are slightly pitch up compared to the fuselage axis, and the panel flies slightly nose up, this allows the fuselage to also give a bit of lift. It’s a small angle but wings are big, and can carry the plane up even at slow speeds, at cruse speed a small angle will still give a massive lift. Consider that lift=Vsquared in the equation. 400knots give you 4 times the lift you have at 200kts.
Have a look to lift, drag diagram vs angle of attack. That’s a milestone in our theory studies to get a license. It makes clear a lot of stuff.
Get any book titled “principles of flight for pilots”. Awesome read. It’s made for pilots, pilots are not expected to have an university engineering degree, these books are as deep as possible and as simple as possible, a fantastic read.
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