Soaring for Sport

Ever wished you could leap off a building and fly away? 

Unfortunately, humans don’t have wings. But wingsuit jumpers don’t let that stand in their way! They wear suits that mimic the skin of a flying squirrel to help them soar through the air!

Did you know?

According to the United States Parachute Association, you should complete at least 200 free-fall (parachute) jumps over the course of 18 months before attempting a wingsuit jump.

Four forces act on an aircraft in flight. They are gravity, lift, drag and thrust. But unlike aircraft, wingsuit jumpers don’t fly. They glide! That means they only experience three of the four forces of flight. Let’s take a look at each of these three forces.

Gravity

Gravity is what pulls the wingsuit jumper toward the Earth. This force acts on jumpers because they have mass. The more mass an object has, the more gravity acts on it. 

One way for wingsuit jumpers to slow their descent is to keep their mass as low as possible. They do this by wearing wingsuits made of a lightweight fabric. But the fabric also needs to be strong. Because as a wingsuit jumper falls, a lot of force is exerted upwards on the fabric by the air. This is called lift.

Did you know?

Skydivers free fall at a speed of about 200 kilometres per hour. Wearing a wingsuit can slow them down to about 60 kilometres per hour!

Lift

Lift is an upward force caused by air (aero) moving (dynamic) over a wing as air moves past it. When you look at a wing from the side, you can see a special shape called an airfoil. The body and wingsuit of a jumper also act as an airfoil. 

As a wing (or wingsuit!) moves through the air, the air splits and flows both on top and below the airfoil. When air is pushed down by the wing (the action), the wing is pushed upwards (the reaction). This upward force is called lift. Lift is always at a right angle (perpendicular) to the direction of motion. 

Did you know?

Newton’s third law states that for every action, there is an equal and opposite reaction.

Unlike a brick, wingsuit jumpers do not just fall straight down from where they take off. Instead, they travel about 2.5 metres forward for every metre they fall. This means they can cover a lot of ground before opening their parachutes. 

So why do they travel so far?

A gliding object moves forward at the same time as it moves downward. The ratio between the distance travelled forward to the distance travelled downward is called the glide ratio. Glide ratio is related to lift. The more lift there is, the further a wingsuit jumper can glide.

Did you know?

American wingsuit pilot Kyle Lobpries holds the world record for the greatest horizontal distance travelled in a wingsuit. In 2016, he flew a record 30.4 km in just under eight and a half minutes!

Drag

As jumpers fall, air is pushed out of the way by their bodies. This is called air resistance or drag. Drag is what you feel when you put your hand out the window of a moving car. When you jump out of an airplane, air resistance is not strong enough to keep you from falling to the ground. But the more drag you can create, the slower you will fall. 

When a wingsuit jumper is gliding, the main type of drag acting on him or her is lift-induced drag. “Lift-induced” means that this type of drag is directly related to lift. In fact, the greater the lift, the greater the lift-induced drag. 

When an airfoil is roughly parallel to the flow of air, the air flows very smoothly past the airfoil. However, as you increase the angle of attack, the air behind the wing becomes less stable. 

Did you know?

The angle of attack is the angle between the chord line and the direction of motion.

When you increase the angle of attack, you are also increasing the surface area for air to push against. If a wingsuit jumper wants to glide for a long distance, then the jumper will point his or her body into the air flow and spread the wingsuit’s arms and legs to generate lift. As the jumper gets closer to the ground, the jumper will turn his or her body upward so that as much of the wingsuit is facing the direction of the air flow as possible. This will increase the drag and slow down the jumper before he or she deploys a regular parachute. 

Did you know?

Wingsuit jumpers don’t just use their wings to slow down. They also use parachutes.

So now you know a lot more about wingsuit jumping. Do you want to try it? Or are you someone who likes to keep their feet on the ground?