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Things fly because of thrust, not wings. Rockets, missiles, don't have wings and yet they still fly even longer distances. Shut the engines of a 747 and it will fall like a rock, no matter how perfect the airfoils.

Bernoulli and Coanda are important but without thrust/velocity there is no lift

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A 747 won’t fall like a rock. It will glide.

You can't say that without mentioning https://en.wikipedia.org/wiki/British_Airways_Flight_009

Where the pilot said what is probably the most British thing ever said in history:

> Ladies and gentlemen, this is your captain speaking. We have a small problem.

> All four engines have stopped. We are doing our damnedest to get them going

> again. I trust you are not in too much distress.

Just in case folks don't click on the link, it was a safe landing and everyone survived. It turns out modern planes can glide quite well.

This is a very important point.

The key difference is that a rock (like any ballistic projectile) accelerates until terminal velocity. In contrast, a 747 (like any airplane) descends with a constant vertical velocity when they lose power.

The engineers at Boeing are going to be really embarrassed once someone tells them they don't actually need to put wings on their aircraft...

not to mention authors of rfc-1925 as well :o)

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