The aerodynamic benefits of a Kamm tail were first discovered some 80 years ago, so it’s a wonder that it’s taken this long for a manufacturer to develop the idea even further, in the way Mercedes has now done. Its new petrol-electric plug-in hybrid can seat up to four passengers, but the stand-out feature is the extendable tail, which emerges at speeds above 50mph, thus helping to reduce the car’s drag coefficient to an impressive 0.19Cd in conjunction with other, less overt examples of shape-shifting aerodynamic magic. 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” – although we’re not holding our collective breath for a long-tailed S Class just yet.

Photos: Mercedes-Benz