Aero helmets need to know

01 Pure speed

very brand will tell you that they’ve created the fastest helmet around, and it’s a claim that’s very hard to disprove given the array of different testing baselines available in a wind tunnel, velodrome or using CFD (Computational Fluid Dynamics). With yaw angles (the effective direction of the wind, usually measured from 0-20°), various speeds (25-45km/h is the wind-tunnel norm) and a countless array of riding positions available to be tested, it’s easy for a brand to find one area, no matter how rare (eg 55km/h at a yaw angle of 20°) and find that their helmet excels in it. What is clear, however, is that aero