# Today I Discovered Why A Plane Doesn't Just Fall Out Of The Sky

Image: NAPARAZZI via Flickr

Flying isn't my favourite thing in the world because I get so caught up in wondering how it all works. "Why is this giant aluminium tube even in the air?", "why is that guy so fidgety?", "why are the lights flickering?"... you get the point. I worry. But this short, sweet explanation of how a plane actually flies puts me at ease.

Thank you, physics.

I've long wondered how a plane flies and, throughout my short existence, been told a variety of different phenomena are responsible for flight but I've never fully grasped the concept.

I understand that the wing is shaped a certain way, that the plane needs to generate thrust via the engines, that it takes air in and pushes it out the back. I kind of understand it all.

However, I have often been thrown by the concept of 'lift'. I've heard several differing physics-based explanations for this and just accepted them to be true.

The most common? Bernoulli's Principle.

Yet, Bernoulli's Principle is only half the story. It describes one specific aspect of flight - the lift force on an airfoil. That is, the air that flows over the top of a wing moves faster than the air that flows underneath a wing and thus, the pressure on the surface of the wing is then lower above the wing than below. This creates an upward force.

Often, this is explained

However, aerodynamic lift (or aerodynamic force) relies on more than just that physical principle to be fully understood. This video, by the excellent YouTube channel Veritasium, explains all of this in under three minutes in the easiest terms imaginable.

Yes, the Bernoulli Principle is something that you should know if you want to understand lift, but you also need to understand how a wing deflects air downwards.

If you've ever worried about how a plane actually gets into the air and stays there, this one's for you. I'm not sure it will help your fear - it may hinder it - but knowledge is power and all that.

Today I Discovered is a daily dose of facts for Lifehacker readers - the weird, wonderful and sometimes worrying. Most of the time, it's just mind-blowing. Let us know if you discovered anything that blew your mind in the comments!