What is the physics involved in skydiving?

Asked by: Leah Hutchinson

Dynamic stability is what allows an arrow to fly nose first. If the arrow starts to flip sideways, the air resistance against the fletching is greater than the resistance at the nose, and the arrow automatically goes back to its initial orientation. Likewise, skydivers don't want to be tumbling end over end and out of control, so they trail their arms and feet behind them to act like the feathers on the arrow.

Answered by: Rob Landolfi, Science Teacher, Washington, DC


There are lots of things going on in skydiving. The things you are probably trying to ask are, 'How can skydivers do the things they do in the sky?' or, 'How can they land safely using a parachute when they are flying at high speeds?'

There is one simple answer. Air resistance. When a mass is moving at speeds like that, air resistance causes them to slow/speed their velocity by their position. If they were in a diving position ' V ' , there is less air resistance, because there is less surface area facing the direction you are going in. If you were to spread all of your limbs out, it causes a much greater surface area, causing more air to collide with your stomach, slowing you down.

As for parachutes, it needs to cover a wide enough surface area in order to cause enough air resistance to slow the mass down dramatically, that's why a huge snap up occurs when you release your parachute, the huge amount of added air resistance at one time causes such a dramatic slow down. BUT! Circular parachutes need a small hole at the tip in order to prevent a flip around. Air doesn't WANT to be resisted, so it tries its best to cause the smoothest path possible, even if it needs to flip that parachute. So, the hole on top causes a smaller chance of that, but air coming up from that hole is immense. So, the easiest solution is a square shaped parachute. It provides the needed air resistance, without the excess area it covers due to its circular shape. Also, it allows skydivers to "steer" their way to a good landing.

Answered by: Phil Sabra, Student, Schofield MS, Las Vegas