German automaker Mercedes-Benz continues to make aerodynamics central to its engineering, and the latest electric CLA with EQ Technology highlights that effort – by streamlining airflow, the company improves driving range and lowers cabin noise, which are key gains for EV buyers seeking efficiency and comfort.
Mercedes says a 0.01 drop in drag coefficient (Cd) can increase long-distance range by about 2.5 percent, adding roughly 230 miles a year for someone driving 9,300 miles. The brand’s pursuit of low drag spans decades, from the 1984 W124 (Cd 0.29) to the 2014 CLA Coupe (0.22) and the EQS (0.20).
The new CLA reaches 0.21 with reshaped wheels, refined underbody panels, and tighter seals, while the VISION EQXX concept pushes to a remarkable 0.17.
Chasing lower drag from the 1930s to the electric era
Mercedes-Benz has refined aerodynamics for nearly a century, starting with Wunibald Kamm’s streamlined “Kammback” designs in the 1930s. Its first full-size wind tunnel opened in 1943 and is still used for airflow and wiper testing. After the 1979 oil crisis, efficiency became a priority, leading to cars like the S-Class W126 (Cd 0.36) and the E-Class W124, the first production model under 0.30.
Record-setters followed – the 1938 W125 “Streamliner” reached Cd 0.16 and 268 mph, while the 1978 C111-III diesel logged nine world records with Cd 0.18. More recent concepts keep pushing limits, from the 2015 IAA’s shape-shifting 0.19 to the VISION EQXX’s 0.17 and the AMG GT XX’s “aerodynamics by wire” plasma system, the EV Report writes.
For the all-new electric CLA, engineers focused on airflow across all variants, using aerodynamic wheels with bicolored full covers that reduce drag slightly more than standard wheels. Furthermore, the underbody builds on designs from the EQS and EQE, with nearly complete coverage and protected suspension arms.
Aeroacoustics and airflow improvements enhance comfort
The German car giant is also paying as much attention to cabin quietness and comfort as it does to reducing drag. Engineers use CFD simulations and full-scale models in the Sindelfingen aeroacoustic tunnel, where 350 microphones identify wind noise around A-pillars and mirrors. Human perception is assessed with psychoacoustic metrics like loudness and sharpness, measured using binaural artificial heads that replicate ear placement.
Aerodynamics also supports safety and visibility. In Untertürkheim’s wind tunnel, fluorescent liquids track how rain or road spray moves across the car, guiding adjustments to pillars, mirrors, and seals to keep key sightlines clear.
Furthermore, Mercedes-Benz’s Sindelfingen aeroacoustic wind tunnel, in operation since 2013, tests airflow and high-speed performance. It can simulate speeds up to 165 mph and uses a treadmill-balance to measure forces accurately, while probes cover a large testing area and a powerful blower circulates air efficiently.
Two climate-controlled tunnels recreate temperatures from -40°F to 140°F for prototype testing. Untertürkheim’s “Large Wind Tunnel” also handles other projects, from bobsleds to stadium roofs. Along with tools like the “Tanja” dummy and 64-microphone arrays, these facilities support Mercedes-Benz in improving both efficiency and cabin comfort, continuing the brand’s long focus on aerodynamics.