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0 pointsTadpole91817mo ago0 comments

According to NASA, the Air and Space Museum, and Wikipedia: you are wrong. Nor does what you're a saying making any sense to anyone who has seen an airplane fly straight.

Symmetric airfoils do not generate lift without a positive angle of attack. Cambered airfoils do, precisely because the camber itself creates lift via Bernoulli.

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ummonk7mo ago

I stated "has its trailing edge at the same angle", not "is at the same angle of attack". Angle of attack is defined by the angle of the chord line, not the angle of the trailing edge. Cambered airfoils have their trailing edges at higher angles than the angle of attack.

Tadpole9181OP7mo ago

Again, not an expert, but how does that jive with the existence of reflex cambered airfoils? Positive lift at zero AoA with a negative trailing edge AoA.

And that seems to directly conflict with the models shown by the resources above? They state that cambered wings do have increased airspeed above the wing, which generates lift via pressure differential (thus why the myth is so sticky).

ummonk7mo ago

Reflex cambered airfoils generate lift because most of the wing is still pointed downwards.

The crucial thing you need to explain is this: why doesn't extending leading edge droop flaps increase the lift at a pre-stall angle of attack? (See Figure 13 from this NASA study for example: https://ntrs.nasa.gov/citations/19800004771)

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0 pointsTadpole91817mo ago0 comments

According to NASA, the Air and Space Museum, and Wikipedia: you are wrong. Nor does what you're a saying making any sense to anyone who has seen an airplane fly straight.

Symmetric airfoils do not generate lift without a positive angle of attack. Cambered airfoils do, precisely because the camber itself creates lift via Bernoulli.

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ummonk7mo ago

Tadpole9181OP7mo ago

Again, not an expert, but how does that jive with the existence of reflex cambered airfoils? Positive lift at zero AoA with a negative trailing edge AoA.

ummonk7mo ago

Reflex cambered airfoils generate lift because most of the wing is still pointed downwards.

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