Your Introductory Guide to Wingsuit Aerodynamics

How Does a Wingsuit Fly? On the Wings of Science.

Brett Kistler jumps his wingsuit from an exit in Switzerland's Lauterbrunnen Valley.
Brett Kistler jumps his wingsuit from an exit in Switzerland's Lauterbrunnen Valley. Image by Annette O'Neil

How can a piece of fabric, cut and sewn to fit a human body, act efficiently as a wing?

If you’ve been watching the sport develop over the last few years, you will have noticed that the “flying squirrel suits” that used to look very much the same from brand to brand have expanded into a vast range of design styles and volumes.

A booming market has facilitated a sprawling showroom of variations, but the basic design tenets remain the same: a human-shaped suit, with two wings connecting the arms and torso and one wing connecting the legs.

Inflated by relative wind, the suit forms an airfoil. That airfoil shape provides sufficient lift to carry a skilled pilot far across the sky (or away from a cliff, or – in some cases – closely over terrain).

Wingsuits work using principles similar to those of every other human-made airfoil, from fighter planes to paragliders. Here’s the science behind the magic. 

Glide, Baby, Glide

A wingsuit is, at its heart, an airfoil built around a person. As such, it behaves like any other airfoil – it creates a combination of the aerodynamic forces of lift and drag. The balance between the two is referred to as the wingsuit’s “glide ratio.” It indicates the aerodynamic efficiency of the wingsuit pilot, and it’s expressed as a number that shows the total meters of forward distance flown for every meter of altitude lost. For example, a wingsuit that goes two and a half meters forward for every meter it falls has a glide ratio of 2.5:1.

...Like a Speeding Bullet

An airfoil requires airspeed to work. In fact, the speed at which the airfoil moves through the air has everything to do with how efficiently it can fly. No plane can take off if it’s not moving, right? The same is true, of course, for wingsuits – and the skilled variation of airspeed is key to success in the discipline.

Airspeed generates lift. Without lift, you ain’t goin’ nowhere.

A skilled wingsuit pilot is able to fly throughout the range of airspeeds available to him/her with his/her body and equipment. The minimum airspeed required to generate sufficient lift to fly is called stall speed, below which the wingsuiter will no longer, by definition, be flying.

The wingsuit pilot’s personal relationship with glide ratio tends to revolve around two key numbers: “maximum glide” and “minimum sink.” The former reflects the airspeed at which the wingsuiter flies the greatest distance forward for each meter of lost altitude. (This number usually hovers around 30–40% greater than the wingsuiter’s stall speed.) “Minimum sink” is, as the term implies, the airspeed at which the wingsuiter loses the least amount of altitude, though he/she will not fly as efficiently as they do at their max glide. Flying at minimum sink delivers longer freefall time, but the pilot covers significantly less distance.

A typical wingsuit’s forward speed – not accounting, of course, for the forest of variables that can affect it – hangs out at around 100 miles per hour. Importantly, faster isn’t always better. Pushing the wingsuit to speeds above that optimum glide “sweet spot” reduces both freefall time and overall forward movement.

…Over Mountains, In a Single Bound

If you’re curious how much forward distance we’re talking about, run the numbers.

A skydive is usually performed from around 12,000 feet over the landing area, and wingsuiters often deploy their main parachutes 9,000 feet (3 kilometers) below that altitude. At a respectable glide ratio of 2.5:1, a wingsuit pilot can cover about 7.5 kilometers of distance. That number doesn’t remain constant. It not only changes with the shape and volume of the wingsuit pilot in his or her gear, but also with the weather conditions (such as headwinds, crosswinds and tailwinds) and the pilot’s airspeed.

The Pilot Really Matters

All those numbers are of obsessive importance to any dedicated wingsuit pilot – and the manufacturers, which are helmed by legendarily skilled and prolific pilots, are keenly aware of that fact.

Each asserts that their offering delivers the best glide, begins flying the quickest and is generally the fastest suit in the atmosphere. No matter how much money you throw at a shiny, new, top-of-the-line suit, the unpopular truth remains: performance depends entirely on the pilot.

Strength and fitness support the muscular exertion required for wingsuit bodyflight (as well as hiking to lofty exit points if a pilot ventures into the BASE arena). A pilot must transition between modes of flight without deteriorating the efficiency of his/her aerodynamic efficiency.

Want to try your hand at it? Here’s how to get started.