Frankfurt LIVE: Mercedes-Benz Concept IAA

Mercedes previews the future of its flagship sedan.

Mercedes-Benz has unveiled its Concept IAA, which stands for Intelligent Aerodynamic Automobile.

Taking the idea of active aero to the extreme, the Concept IAA changes its shape based on speed to slip through the air more efficiently. At about 50mph the Concept IAA automatically extends eight segments at its rear, increasing the car's overall length by 390mm, and also deploys several flaps embedded in the car's front bumper. Even the Concept IAA's wheels change shape to cheat the wind, a technology Mercedes has dubbed Active Rims.

When in aerodynamic mode Mercedes says the Concept IAA has a Cd of just 0.19. For comparison, the Mercedes-Benz CLA is currently the most aerodynamic car on the market with a Cd of 0.22.

At lower speeds the Concept IAA remains in what Mercedes' calls design mode. With its body panels in design mode, the Concept IAA closer resembles a typical four-door coupe than a vehicle from outer space.

Inside the Concept IAA boasts an interior that isn't far removed from production viable. In fact, Mercedes says the Concept IAA previews the interior direction of the company's next-generation S-Class.

The biggest highlight of the Concept IAA's interior is the use of new Optical Finger Navigation (OFN) buttons on the steering wheel. Similar to the central touchpad used in contemporary Mercedes vehicles, the OFN buttons rely on a touchpad rather than a physical button to interact with the vehicle's controls. In the Concept IAA, the buttons on the left side of the steering wheel control the left-hand side display while the controls on the right control the LCD screen closest to the passenger.

The Concept IAA is powered by a gas-electric plug-in hybrid drivetrain that provides a combined 279 horsepower. The Concept IAA has an all-electric range of about 40 miles and can return up to 194mpg in aerodynamic mode. Mercedes notes that the Concept IAA's efficiency gains are most notable on the highway as the aero tweaks don't help much as lower city speed.

"Captivatingly sporty lines, fascinating technical solutions: the 'Concept IAA' symbolizes the emotional core of Mercedes-Benz: The best or nothing. And it shows in a host of details what our customers can look forward to in future production models," said Ola Källenius, Member of the Board of Management of Daimler AG, Mercedes-Benz Cars Marketing & Sales.

Look for elements of the Concept IAA to make their way into future Mercedes production vehicles in the coming years.

Live images by Ronan Glon.