MERCEDES-BENZ has revealed that progressive aerodynamic treatments throughout the development of the new-generation A-Class have helped make it one of the most efficient as well as quietest small cars in the world.
While its drag coefficient figure from 0.25 for the base version (not sold in Australia) and a frontal area of 2.19m2 are only 0.01cd and 0.01m2 better than the best that its 2012 predecessor could manage, in the real-world versions where drag-inducing wide wheels, big air intakes and spoilers up the coefficient towards the 40s, the gap between the two worst figures between generations (0.32 and 0.38 for new and old respectively) is the equivalent of shedding up to 200kg of mass in terms of improving efficiency.
According to Daimler AG aerodynamics and aeroacoustics expert Christoph Albrecht the result makes the fourth-generation A-Class the most aerodynamic production compact hatch range in history, with wind noise slashed by up to 30 per cent as a result model-for-model.
“Our biggest focus was to reduce drag as well as noise entering the cabin,” he said. “The aim is for the new A-Class to be the quietest in its segment.”These twin goals were achieved with intensive detail work during computer-based simulations, even at the design stage, given a reduced front area and lower roof compared to the old model made a difference.
A larger rear roof spoiler, optimised radius of the A-pillars, bonnet aero lip, repositioned and reprofiled exterior mirrors, improved seals (such as around the door apertures and headlight surrounds), ‘aero optimised’ front bumpers incorporating special foglight housings, and a specific shape of the wheelarches also brought important contributions to better overall air flow.
Additionally, there has been an overhaul of the underbody airflow system with larger panelling for the engine compartment, main floor, rear axle and rear diffuser area, as there are several varying engine and exhaust combinations that necessitate different components according to models and variants.
Plus, unique tyre designs are also featured to help with the way air passes beneath the car.
A new-to-series ‘Airpanel’ grille shutter system, as seen in some E-Class variants, that opens and closes according to cooling requirements is fitted to the most eco-focused variants such as the A180d, although it won’t be offered just yet in Australia.