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A quick guide to aero helmets

We explain the options now available, from long-tail to covered and round

Are you aiming to cut drag this season but confused by the different shapes and sizes of aero helmets on offer? Let Rob Banino be your guide…

We’re definitely seeing aero helmets evolve as manufacturers realise the ‘one tool for every job’ approach doesn’t work. In other words, when it comes to aero helmets, it’s horses for courses.

>>> Aero helmets for triathletes – how and why to use them

Long-tail aero helmets used to be the only option for drag-reducing head gear. But, as helmet manufacturers have learnt more about aerodynamics, they’ve seen how rider, course and conditions can affect a helmet’s performance.

They’ve realised that the most aerodynamic helmet in one situation isn’t necessarily the most aerodynamic – or practical in another. This is why new designs that are tailored to different circumstances are appearing. Broadly speaking, aero helmets now fall into three clear categories: long-tail, mid-length and covered/round…


When positioned correctly, a long-tail lid can offer big aerodynamic benefits. But that diminishes if the wind is unpredictable or if the rider can’t keep his head where it needs to be (which can be difficult given the weight of these helmets). As such, they’re often best suited to shorter time-trials on flat courses in calm conditions.


These are essentially docked long-tail helmets. The shorter tail makes them lighter and suitable for a wider range of situations, as Simon Smart of Drag2Zero explains. “When a rider’s head moves around a lot, a long tail can cause more drag than is saved. Shorter tail helmets are less sensitive to position and, for most, will have a lower average drag over the course of a race.”


These aim to strike a balance between weight, cooling and aerodynamic efficiency. They include the UK Sport helmets supplied to the Brownlee brothers at the 2012 Olympics and the Giro Air Attack worn by Leanda Cave at Ironman Hawaii 2012.

The Brownlees’ helmets needed to be light, easy to both put on and remove for fast transitions, and able to work well in a bunch where the Brownlees would be turning their heads a lot to watch their rivals.

As for Leanda’s choice, she explains that previously she found long-tail helmets “too hot to wear in Kona, so I used a road helmet prior to 2012. But [Leanda’s helmet sponsor] Giro wanted me to try the Air Attack, which they’d found to be 70% cooler than their long-tail Advantage helmet but only 10% less aero. The Air Attack doesn’t replace Giro’s long-tail helmets, as it doesn’t perform as well in the wind tunnel, but it’s significantly faster than an uncovered road helmet.”

(Image: Rich Cruse / ITU)

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Profile image of Jamie Beach Jamie Beach Former digital editor


Jamie was 220 Triathlon's digital editor between 2013 and 2015.