We were taught in school that aeroplanes fly because the wings are bulbous on top, so the air has further to travel, therefore does it faster, therefore at a lower pressure, so developing lift. I heard this explanation given by a teacher to a class at an 'hands on' demonstration in the Science Museum with an expanded polystyrene wing and a hair dryer - shure enough the wing convincingly shot upward when inserted in the air flow. After they had gone I tried it myself, and it became clear to me that the convincing lift came not from the Bernoulli effect but from the angle of attack - held level there was no detectable lift; the children were being conned.

And in any case, aeroplanes can fly upside down, can't they?

So for a Jumbo at cruising altitude in level flight what proportion of the lift is due to the angle of attack, and what proportion to the hump in the aerofoil?

While I'm sure personal human flight is much easier through fixed wings and some sort of rocket or jet propellant, however, these are not nearly as cool as a nice set of wings like a bird. I know humans are much bigger and heavier than any flying species of bird and are therefore not naturally built for flight at all. But surely this isn't beyond the capabilites of humans?