The car also shows the frugal petrol-electric plug-in hybrid powertrain technology and contemporary touch-based interior controls the company plans to use on future road cars.
Called the Intelligent Aerodynamic Automobile (IAA), the four-door saloon features an extendable body that provides it with a drag coefficient of just 0.19 in its most efficient ‘long tail’ form.
The dimensions and silhouette are said to preview those of the third-generation CLS, due out in 2017.
The IAA automatically switches from ‘design’ mode to aerodynamic mode when it reaches 50mph, with elements in the tail section extending to increase overall length by 390mm. At the same time, flaps in the front bumper and louvres in the grille are deployed to improve airflow around the wheelarches and underneath the car.
The new exterior styling is set to filter down into future road cars. Mercedes-Benz sales and marketing boss Ola Källenius said: “It shows in a host of details what our customers can look forward to in future production models.”
At 5040mm in length in design mode, the IAA concept is 100mm longer than today’s CLS. In aerodynamic mode; with its body fully extended, it stretches to 5430mm, 185mm longer than the long-wheelbase S-Class. Width and height are 1995mm and 1305mm respectively.
The 2975mm wheelbase is 100mm longer than that of today’s E-Class and CLS, hinting at a larger interior in the next generation of both models. The concept rides on the latest evolution of Mercedes’ MRA platform.
Power is provided by the petrol-electric plug-in hybrid system used in the C350e Plug-in Hybrid. It pairs a 208bhp turbocharged 2.0-litre four-cylinder petrol engine with an 80bhp electric motor to provide a total output of 275bhp and 442lb ft.
Mercedes is yet to provide any performance claims, although computer simulations suggest that the new concept is capable of delivering an electric-only range of up to 41 miles and combined fuel economy of 191.6mpg.
The lavish interior of the IAA closely previews that of the upcoming new E-Class. Building on the design used by the latest S-Class, it features a long, horizontally mounted high-definition monitor, as well as a centre console with touch-sensitive controls.
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