The most striking feature of McLaren’s new Elva sports car is the complete absence of any kind of a top, even including the windshield. The design makes for wonderful theater, but how in the world does this actually work for drivers who don’t want to wear a full-face racing helmet for protection from the wind blast at speed?

We’ve all put our hands out the window of moving cars. Imagine the force of that wind hitting you in the face! Rather than diverting that airflow with glass, McLaren engineers are employing a wall of air to shove the airflow up and over the Elva’s occupants. 

They call it the Active Air Management System, and if this sounds like a dubious proposition, McLaren has released a video outlining the system’s function.

Image source: McLaren Automotive

“If you are sitting in the car with the system deployed at, say, 100 kilometers an hour or 120 kilometers an hour, you can sit here in relative calm,” explained Dan Parry-Williams, Director of Engineering Design, McLaren Automotive. “Your hair, if you have hair, is unruffled,” noted the decidedly balding engineer. 

The Elva’s purpose is to return modern sports cars, which have been criticized as being too antiseptic, back to their roots. “When we talk about pleasure and exhilaration, and exposure in this case, that meant stripping the car of absolutely everything, including windscreen. So effectively no weather protection at all. And that presented the aerodynamic challenge for this car.”

A challenge, indeed. One that can be realistically solved? That’s what McLaren’s team wondered, too. “With absolutely nothing between you and the wind coming at you, would it be possible to create a virtual canopy? And that was the challenge we set ourselves.”

Parry-Williams demonstrates the exit angle of the Active Air Management System's air jet. Image source: McLaren Automotive

The solution is to re-route air flowing into the car’s grille and blast it at the air flowing over its hood toward the occupants. “Inside here, there’s a giant hook-shaped duct,” said Parry-Williams. “Air is channeled in the front of the car from the area with the highest pressure obviously, as the car is pushing its way through the air. This air is all ducted and channeled through the center of the car and is turned through 120 degrees and actually exits the top surface in this direction. So it is fired out of here at very, very high velocity. Of course, there’s onrushing air coming behind it. And that high-energy channel of air that is being forced up here is bent back by the oncoming air and is effectively curved back all the way over the canopy.”

Then he admits that, well, they also cheated a bit. A jet of air is great, but at speed, it needs some help. So the Elva has a ramp that slide upward just behind the exhaust vent for the air shield, providing some rigid support to the air stream and a firm obstacle to air headed toward the car’s occupants. “This actually rises at speed when you start going faster and faster,” said Parry-Williams.

The driver also has the option of getting the full blast of wind straight in the face, if they want to give that a try. “The whole system can be switched off from inside the car,” he said. “There is an internal flap that shuts the whole duct off.”

In that case, be sure to bring a helmet with a faceshield!

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Dan Carney is a Design News senior editor, covering automotive technology, engineering and design, especially emerging electric vehicle and autonomous technologies.