First details of the Mercedes E-class cabrio have been released, including how the innovative retractable wind deflector that sits at the top of the windscreen works.

Called Aircap, the driver-operated system raises a wind deflector on the tip of the windscreen to direct wind 20cm higher, over the top of the passenger compartment. It works in conjunction with a rear deflector to eliminate buffeting and reduce noise with the roof down.

It can be raised up to 99mph, and operates effectively up to 161mphph. As a result, Mercedes says the car is the first cabrio that can be used as a permanent four-seater throughout the year and on any type of road.
The system was developed over “between two and three thousand hours” in the wind tunnel according to Teddy Woll, Mercedes’ senior manager of aerodynamics.It is made up of 211 different parts, is built with 44 different materials and has been tested in extreme conditions through more than 10,000 cycles.

However, although Mercedes says it could be used on other open-top models, its effectiveness makes it most practical only for four-seaters. Insiders also say that Mercedes designers are conscious that the system, while practical, would not be welcomed by style conscious buyers of sportier two seaters.
The coupe version of the new E-class is the world’s most aerodynamic production car with a Cd of 0.24, but the cabriolet’s rises to 0.28. Raising the Aircap further disturbs that figure, rasing fuel consumption by an additional 1.2mpg on average.

The E-class cabrio is based on the E-class coupe, and will go on sale in the UK next March and will have Aircap fitted as standard. Air scarf, which directs hot air around occupants’ neck, will be available as an option.

It is around 70kg heavier than the coupe, and will have the same range of four, six and eight-cylinder engines as the latest E-class saloon and coupe, including the twin-turbo four-cylinder E250 CDI.

Prices haven’t been determined yet, but sources suggest they will be around five per cent less than on the current car, in line with reductions for the latest generation saloon and coupe models