Behind the Aerodynamics of Rudy Project Aero Helmets

In triathlon racing, an aerodynamic bike helmet produces free speed. So, all things being equal, an athlete pedaling their bike with the same effort will go quantifiably faster with an aero bike helmet. Wind-tunnel testing by 220Triathlon has shown that an aero helmet, with its smooth front and long rear tail, will shave an average of one minute off a 40km/25 ride versus a more conventional road helmet. For Ironman triathletes powering through the 112-mile bike leg, that means they would complete the bike portion 4.5 minutes faster. 

But not all aero helmets are equal. An aero design aims to drive down a helmet’s coefficient of drag area (CdA) number. The closer it is to zero, the better. At the same time, an aero helmet must fit comfortably and stay comfortable for hours and hours of cycling in warm-to-hot environments (The bike leg of an iron-distance triathlon is 112 miles.) Figuring out how to do both would be the crowning achievement for aero bike helmet designers. With the Wing, Rudy Project just might have pulled it off. 

Wind-Tunnel Tested

Rudy Project teamed up with the aero geeks at Swiss Side, utilizing computational fluid dynamics and wind tunnel testing to create the Wing. Who is Swiss Side? They made a name for themselves in Formula 1, the absolute top of motorsports engineering and design, helping create the fastest race cars on the planet. By partnering with their designers, Rudy Project was able to build a fast helmet that stays fast in various head positions. 

Previously, a triathlon helmet was most aerodynamically efficient when the rider held their head in the optimum position. Easy to do for a couple of minutes; hard to do for hours. Wind-tunnel testing confirmed that the Wing’s “chopped” rear end and exhaust port incurred no penalty in straight-line cycling, and, unlike traditional aero helmets, it didn’t punish the wearer for turning their head or looking down.

Seamless Helmet and Visor Integration

One of the primary benefits of an aero helmet designed by a leader in sports optics and cycling helmets reveals itself in the smooth integration of the Wing’s helmet with its visor. Understanding the importance of optimized vision with top performances, Rudy Project didn’t cut corners with the Wing’s visor. It blends almost seamlessly into the helmet line for maximum aerodynamics yet still gives the wearer a full field of vision for optimal clarity and safety.

A Cooler Head Equals a Faster Cyclist

Vents and air channels in a bike helmet do a simple yet important task — they help the wearer stay cool. Staying cool is critical to an athlete’s ability to send power through their legs to the pedals. If the athlete starts to overheat due to an aero helmet with no ventilation, their body will move blood away from the legs and lungs to the skin, where it can better release heat through sweat (This is why you look red in the face when you get overheated). Over time, the body’s inability to keep the head cool will cut the amount of power an athlete can put into the pedals.

Conventional wisdom holds that vents and air channels are not aero. However, a strategically located vent can draw airflow around the wearer’s head while still lessening the aerodynamic negative impact. With the Wing, the center vent, when opened, reduces the helmet CdA by a minuscule amount — less than 1% — as this independent video review and test from ERO Sports demonstrates. In addition, the Wing’s chopped rear vent hole does double duty: it helps hot air escape from the wearer’s head, and that airflow acts as a diffuser to reduce turbulence off the rear of the helmet and settle that airflow’s continued path across the cyclist’s back. The overall benefit of that ventilation port will well exceed any aero penalty in terms of sustained performance over time.