Maybe there are some questions like this... But I would like to listen to your answers... Thank you! As many people say, there are many ways that describe incorrectly the generation of lift. Two models survive today which are supposed to explain this aerodynamic force, or at least, a part of it: the Newton and the Bernoulli model. Both models are widely spread today among universities. You can get deeper in the topic understanding the Kutta-Joukowski Theorem, and the role of the circulation in this. But I think this is a less intuitive way to understand it and (as Bernoulli), it requires some assumptions (potential flow...), so I think the best way to explain this effect is the Newton explanation, as Anderson thinks too, just because we only use the third law as an axiom. Every one of these explanations require the flow to curve, due to the body shape or due to an angle of attack (as in flat plate). My question deals with paper planes. How does the lift generate? Where does it come from? The wings of a paper plane are approximately flat plates, so they require a positive angle of attack to produce lift. Some explanations I have heard: - You must throw the paper plane with an angle of attack so as to get the lift produced. I don't agree with this. I (and I'm sure you too) have seen paper planes flying with a zero angle of attack, with both the aerodynamic velocity and wings paralell between them. The classic paper airplane can make good flights parallel to the ground, with its wings with a zero angle of attack. - When the paper plane is in the air and it starts to fall, the induced velocity creates an angle of attack (that is one of my professor's explanations). This is an interesting question, but I don't agree neither. When we see a paper plane flying, it flies in an straight trajectory, it doesn't need to fall to create the lift, so there is no induced velocity (and no induced angle of attack). - The angle of attack is not zero despite of throwing it with zero angle of attack. This is due to the relative position of the mass center and the pressure center. The aerodynamic forces create a positive pitch coefficient and then the wings get an angle of attack. I don't agree with this question due to the same facts explained before. I have seen paper planes with zero angle of attack (and without any pitch moment) flying. You can search for some answers (http://aviation.stackexchange.com/q...airplanes-create-lift-if-their-wings-are-flat, http://www.scientificamerican.com/article/bring-science-home-paper-planes-drag/), and even some scientifical papers: http://msc.tsinghua.edu.cn:8090/down/1.pdf http://www.enu.kz/repository/2009/AIAA-2009-3958.pdf In these both papers, there are some results in the Cl vs AoA graph that show that with a zero angle of attack, there is a small amount of lift created (Cl>0). So, I think I have explained my question the best I can. Can a flat plate with a zero angle of attack (and by extension, symmetric airfoils) create lift in some manner? We have always heard (and studied, some of us) for ages, that for a symmetric airfoil with a zero angle of attack is impossible to create lift. Of course, there is an explanation of how the lift works in a paper plane based on turbulence (it has to do with vortex created in the leading edge and the lower pressure in the extrados), but I am looking for a more wide explanation (like Newton or Bernoulli). If there is no change in the direction of the flow, why does a paper plane fly? In which way I'm wrong? Thank you everyone for reading such a long post! And of course... Sorry for my English! I would like to explain this topic as well as using my mother language. Pd.: I would like you to show me the best explanation of generation of lift you have ever heard. It may help me.