Like all the best ideas, the Elva’s Active Air Management System appears deceptively simple; in fact, it has taken all our aerodynamic knowledge and expertise to perfect this pioneering wind deflector
Elva’s Programme Manager, Jonny Swinhoe, is keen to dispel any notion that developing the car’s Active Air Management System (AAMS) has been straightforward: ‘So much effort has gone into really perfecting the air flow,’ he says. ‘It’s not just a case of “We think it’s a good idea to put a duct on the front of the car” – this system has extensive wind-tunnel testing and hundreds of hours of Computational Fluid Dynamics (CDF) built into it.’
‘The AAMS has demanded F1 levels of precision,’ Jonny goes on. ‘We’re talking about using the same tools that the McLaren Racing F1 team use to predict and manage airflow in our racing cars.’
That’s led to tiny details that no-one will notice unless they’re pointed out: ‘Towards the end of the aero development, we set about doing really minor changes to the surfaces that feed the AAMS. If you look at the front of the car, for example, there are two vertical posts that connect to the splitter – we call them the ‘splitter fangs’. It was identified that we could improve flow through the ducts by putting a radius at the top of these, where they intersect with the roof of the duct. These are really detailed changes, but they show how much attention we put into getting the airflow right.’
The result is the Elva’s dramatic, open cockpit with no windscreen – a cabin that’s completely comfortable for occupants up to speeds around 110kph (70mph). Jonny explains the procedure: ‘When you start the car, the system is off. When you press the AAMS button in the cockpit, a valve opens just behind the nose of the car, inside the air intake. When you start driving, this directs airflow up through the duct in the bonnet, deflecting the oncoming airstream. This is enough to maintain comfort up to around 30kph (20mph) – above this speed, a carbon fibre vane automatically deploys, rising up out of the bonnet to further deflect off that airstream and at that point you’ve got full functionality of AAMS. When you slow down or come to a stop, the vane goes down again, rather like an automatic spoiler on back of a car.’
Explaining how it works is one thing, but describing what it feels like is another matter: ‘It’s funny,’ explains Jonny. ‘You can understand it in theory, but everyone who actually drives the car still gets out saying it’s much more effective than they were expecting. At speed, you can hold your hand above your head and it’s like sticking it out of a car window on the motorway – suddenly you feel the force of that rushing airflow and you realise the cabin is cocooned in a bubble of still air.’
After two years of development, the Elva shows what’s possible when Formula 1 technology meets the sleek, voluptuous curves of an open-top supercar. No wonder we call it our Ultimate roadster.