Delta wing is a term that comes from aircraft design where the wing planform (not a typo) is in the form of a triangle. Usually aircrafts like these do not have horizontal stabilizers (tails) and are famed for efficient high speed speed flight. HAL Tejas is one example that pops to mind, that makes use of the tail-less delta wing configuration. Ben Bowlby, a Briton who started building and racing his own cars at a very early age is bringing his interpretation of the delta wing design to motor sports.
Ben Bowlby and Riot Engine have one thing in common. We believe there has been little, if any innovation over the past few years in racing, case in point Formula 1 where rules clearly stipulate how many cylinders can be used, what metals and composites to use, the angle of the cylinders and size of the intakes and so on.
Ben Bowlby, the man who came up with the concept of DeltaWing and designed it explains : “It [DeltaWing] was born out of the fact that motor racing, particularly in the States where I’ve been based for some years, has become dominated by spec formulae – which stifle design and innovation. The rules are so tight that the cars are basically all the same. I was witnessing the decline in interest in motor racing, seeing my own kids growing up and asking why they had to watch the race as ‘it was so boring’. I realised that I was part of a dinosaur industry… or one at least at risk of becoming a dinosaur.”
Bowlby wanted to build a racing car concept that would be more aligned with the R&D that a automotive manufacturer undertakes for their road cars. Bowbly understood the need to reduce the costs involved in motor sports. Focus was also reducing aerodynamic drag, reducing weight massively, and the need for a downsized engine that could deliver outstanding performance in spite of its size while being as efficient as possible.
The final product is the Nissan DeltaWing unveiled on the 13th of March, 2012. The DeltaWing is unlike any other racing car currently on track. The driver sits well back in the car, almost over the rear axle and looks ahead down a long, narrow fuselage to narrow twin front tyres, specially created for the car by tyre partner Michelin. With a rear-mounted engine, the car has a strong rearward weight bias, which makes it highly manoeuvrable, while its light weight and slippery shape make it far more efficient, says Nissan.
DeltaWing started out life as one of the prospective choices to replace the ageing Dallara chassis in the IZOD IndyCar Series. When the DeltaWing concept was rejected for the 2012 season, even though it met all the requirements put forth by IndyCar’s ICONIC Committee, Bowlby decided to take his creation elsewhere. Meetings with Don Panoz, one of the officials at American Le Mans Racing, followed up quickly with the organizers of Le Mans 24 Hours Racing, including Jean-Claude Plassart, President Automobile Club de l’Ouest (ACO) soon gave the DeltaWing new life.
Getting involved next in the project was Dan Gurney from All American Racers who would build the DeltaWing and Duncan Dayton who owns Highcroft Racing, the team that will be fielding the DeltaWing as an entrant at Le Mans. In June 2011, ACO invited DeltaWing to take its start from ‘Garage 56′, the spot in the pitlane reserved for experimental cars. Of course, a car designed for the IndyCar series didn’t meet the regulations of Le Mans 24 Hours, and so will race with the number 0, ineligible for any podiums.
It helped that Dr. Don Panoz, the founder of the American Le Mans Series is the managing partner of Project 56, which has been set up to get DeltaWing to Le Mans.
Michelin was announced as the first technical partner, followed by key suppliers including EMCO Gears (gearbox) and Performance Friction for the brakes. Until March 2012, DeltaWing was still looking for a technical partner who would provide the engine.
“But this is just the start of our involvement. Nissan DeltaWing embodies a vast number of highly-innovative ideas that we can learn from. At the same time, our engineering resources and commitment to fuel efficiency leadership via our PureDrive strategy will help develop DeltaWing into a testbed of innovation for Nissan”.
“This announcement gives Nissan the opportunity to become part of a ground-breaking motorsport project and one which could shape the future of the sport,” he added.
Nissan stepped in primarily under the direction of Darren Cox, General Manager, Nissan in Europe. “We see much of our own character and spirit in DeltaWing’s engineering innovation. It’s a great fit. We are making a bold statement here, and it’s one that reflects our growing confidence in Europe. We had a record year in 2011, while globally we handled big problems like the Japanese earthquake and the floods in Thailand significantly better than our rivals. We are right to be confident. Besides, backing a project like this once it’s successful is too late. We see something really innovative here and we are prepared to take a calculated risk to help take it to the next step.” explained Darren Cox when asked why Nissan is confident enough to back the DeltaWing project until the car proves itself.
Key Design/Engineering Features
One quick glance and you know this racing car is different. Very different. The rear track width is about 70 inches whereas the front track is only 24in! DeltaWing Racing Cars says this shape reduces drag by half compared to conventional IndyCar racing cars. DeltaWing has a very small frontal area and the design uses a twin vortex underbody downforce system. There are no wings up front that would be influenced by the ‘wake’ from the lead car. This wake from the lead car passes over the car behind with minimal disruption to the underbody downforce performance. The wheels are also shrouded, which again reduces drag and improves safety.
The DIG-T race prepped engine, a 1.6-litre four-cylinder engine, featuring direct petrol injection and a turbocharger will power the DeltaWing in its Le Mans debut on the 16th and 17 June 2012. The DIG-T engine is expected to produce around 300 bhp and maximum torque output of 312Nm, sufficient to give Nissan DeltaWing lap times between LMP1 and LMP2 machines at Le Mans, despite having only half the power of those conventional prototypes. It features the same technology found in Nissan road cars, such as the range-topping Nissan Juke DIG-T says Nissan.
While conventional wisdom says a 50:50 weight distribution works wonders for handling, DeltaWing takes a different approach aiming for a more rearward bias than traditionally seen with 72.5% of the mass on the larger rear tires. Also 80% of the aerodynamic down force acts on the rear of the car which the firm says will improve inline traction under acceleration. So what’s keeping the front of the car on the ground?
Will there be any grip at all for the front tyres? Won’t such a car understeer? While we do have to wait until the DeltaWings debut to find out, Bowlby explains “It’s got a very benign, but exciting, handling characteristic in that it is an oversteer limit vehicle. In other words, when you reach the threshold of grip the tendency is towards oversteer. This is unusual in a rear-engined racing car which, unless provoked, is normally an understeer limited vehicle with an inevitable snap oversteer event at the limit of control. In our case we will have progressively increasing oversteer, allowing the driver to counter steer and maintain that threshold condition in a very controlled way, something you can’t do in a car that understeers. From a racing driver’s standpoint understeer is an unstable condition because you can’t correct it other than by slowing the car and starting again, but with controlled oversteer – intrinsic in the layout of DeltaWing – it’s much more controllable”.
DeltaWing is also unique amongst today’s racing cars since 60% of braking force is generated behind the center of gravity. Locking propensity of the inside front wheel on corner entry is greatly reduced says the company, but does not explain how. Advanced computer modeling of structures, impact energy management, aerodynamics, vehicle dynamics and tires has been used to develop the virtual DeltaWing car and its performance has been simulated on each configuration of race track.
Modern advanced materials and CNC construction techniques have been applied to achieve gains in light weight structures and occupant safety. Having started out life as a replacement for the existing IndyCar Dallara chassis, the focus was on improving driver safety. The driver position, restraint layout and energy absorbency facility have been designed with the latest data on ‘survival criteria’.
The DeltaWing also has innovative gearbox electronics. The car can run a torque vectoring system, which is unusual on a racecar. “Normally it’s banned but this car is outside rules and regulations so we can use this technology, which is relevant to our road cars (Juke and GT-R have advanced Torque Vectoring systems). By working very closely with them and embedding our engineers in the team, we can learn from them. People talk about moving technologies from F1, but in truth that hasn’t happened recently; indeed technology that started on road cars is now in F1 (Hybrid or KERS). However, Nissan sees a number of things on this car that could have a direct application on our road cars.” says Darren Cox.
“It’s a five speed sequential ‘box built for racing, but, as on Nissan Juke, features torque vectoring technology to control the torque going to each wheel to enhance the cornering, stability and performance. We will be interested to see how this technology performs in a racing environment with particular regard to durability. It’s early days, of course, but I am anticipating deep technical exchanges between NTCE and DeltaWing.” explains Jerry Hardcastle VP, Vehicle Design and Development, Nissan Europe.
The DeltaWing will also have FIA spec carbon fibre monocoque. Inconel four into one turbo solenoid controlled wastegate actuation takes care of exhaust duties. The rest of the body is of course, carbon composite.