A common question from people when they fly is why they feel what they do.  I’ll talk about some of the specific feelings you will experience in another post, but I thought you might be interested in the science behind why you feel these things.  Don’t worry, we won’t be splitting the atom!

Here’s some info I posted on the Taking Flight FoF forum a while back:

Have you noticed in an elevator that you feel when it starts moving?

Then you stand around looking at the numbers on the floor-display, or staring at the door, or trying not to look at the crazy and slightly smelly rumple-suited drongo at the back of the lift. The one thing you DON’T notice is that you are moving. The only thing that shows you how far or fast you are moving is the numbers. Close your eyes if you don’t believe me.

Then, when you approach a chosen floor (sadly not yours, because you got in the wrong lift and 8 people have chosen floors before yours) you will feel the lift slow down.

You felt the CHANGE in speed, both when the lift started and when it stopped, but you cannot feel the speed itself.

The great old-timey scientist Isaac Newton described this in his First Law of Motion… an object will keep moving until a force acts on it. What this means is, once you have been acted on by a force (accelerated) you will keep moving at that speed until something makes you stop. No force is acting on you while you are moving at a constant speed.

It feels, therefore, just like it would if you are still.

In an airplane, just like in a lift,you will FEEL the acceleration as it starts (it’s takeoff roll), because you are changing speed.

You will also feel it as the plane points into the sky, as you are changing direction (which is kind of like changing speed, actually).  You will similarly feel if the plane levels off, and when it starts it’s descent (again, change in direction is kind of the same as a change in speed).

And, of course, if it is bumpy there are little accelerations up and down as the plane bounces through the bumpy air (slight changes in speed, in the up and down sense), and you will feel these too.

Why do we feel acceleration? Because we, as king monkey, have evolved to have certain senses about the world around us and our involvement in it, that give us an advantage over the lesser beasts.

We think that we can feel that we are moving, but the actual way it works is we feel the CHANGE in our speed, and observe how our view of the world CHANGES as we move. Shut your eyes and you’d never know you were moving.  When moving at a constant speed (or velocity, to be strictly correct) your body feels as if it is remaining perfectly still.

(It’s something to do with the way the inner ear works, and the physics of it is that the curly gooey things in your ear move when you are accelerated or decelerated, and don’t move otherwise. I apologise if this is too technical.)

Just like your experience in the elevator with the rumple-suited guy, who has just taken off his shoes.

Won’t this elevator EVER get to my floor? (The time dilating effects of an 8-stop lift ride are a topic for another time!).

Here’s an in-depth explanation of Newton’s first law of motion, for the science minded among you: