Sunday, 19 July 2015

Back to the Future – How Ground Effect could save modern F1

Sometimes the answers can come from the past..

What should an F1 car be? Ask most fans and they would tell you the fastest circuit race cars on the planet. They should have a degree of difficulty to drive that allows talent to shine through. They must have a purity in design and driving experience that reflects the pinnacle of motorsport. The racing spectacle should be as entertaining as possible whilst the sport being at the forefront of technology to keep the manufacturers involved.  This balancing act and ideal vision of the sport has become somewhat eroded. Yet look into the sports past and you will find a technology that could re address this balance and bring the spark back the audiences are currently longing.

Still tail happy at low speed
What are the modern turbo F1 cars like to drive? Certainly they are not the turbo charged monsters we saw in the 1980s era. Many including me fantasised of ridiculously powerful cars squirming sideways and forcing the drivers to wrestle them into submission. Even with recent rules restricting downforce, modern cars have so much more grip than their 1980s counterparts. They feel glued to the road and more refined compared to rocket propelled shopping trolleys. At slow speed the back end will still squirm under the huge torque of the turbo engine breaking traction. But throw the car into a bend at speed and the front wing and complex rear diffuser will produce a huge amount of downforce making the car feel stable and planted.  That’s right, modern F1 although recently dominated by engines is still all about downforce.   Back in the 1980s teams were dominated by engineers, today the design teams are guided by aerodynamicists. HNDs have made way for Aeronautical degrees as reluctant poster boy Adrian Newey proved with success that every aspect of the car should be optimised for aero efficiency.  Now aerodynamicists lead the design direction of the car.

Complex modern front wings
There is one single component on an F1 car that generates around a third of this downforce. It is the front wing. By means of hugely complex winglets and end plates these wings also play a vital role in channelling air around the disruptive tyres and under the car. As rule changes evolved this component has become the holy grail of car design. You might find your F1 nerd trying to impress by attempting to explain the latest wing upgrade that he has read in Scarb's blog or Autosport magazine. The truth is such is the complexity you truly need an Aeronautical degree to really understand the design direction of front wings. Teams plough millions into developing them which individually cost alone around £100,000. Think of this when Maldonado love taps his next opponent and comes into the pits for a new one.

'Dirty Air' phenomenon
The serious problem with this hugely complex piece of carbon fibre is overtaking. When chasing another driver you may hear a radio transmission complaint about ‘dirty air’ or losing time tucked up behind an opponent. Once a following car gets close behind a car in front it enjoys the advantage of a hole in the air being punched open. This is great down the straights as the hole generated by the opponent allows it to ‘slipstream’ behind and gain an advantage from less drag. However, approach a corner under braking and enter a bend and this lack of air doesn’t allow the front wing to work. The air flow it does receive has already been shaped and manipulated by the car in front so doesn’t flow as it should. This ‘dirty air’ reduces front end grip and produces understeer, meaning the car doesn’t want to turn into the corner. Continue to try and close the gap and overtake and this understeer produces unnecessary front tyre wear and can rapidly snowball during a race when tyre wear is all important. Cue drivers backing off and saving their tyres and accepting the position they are in. This is caustic to racing and a sad reality of modern F1. The slow reacting FIA are aware of this and have tried to band aid the racing with DRS zones to artificially boost the chasing driver. In 2009 ‘tea tray’ style wide front wings were bought in to channel air around the outside of the front tyres thus attempting to make the front wings less sensitive to dirty air. Although we saw plenty of overtaking in the following years this was down to new high-degradation Pirelli tyre compounds and the introduction of DRS. The front wings were still very sensitive to dirty air and increasing their size had only increased cornering speed. They were soon shortened in 2014.

Ground effect 'Venturi' tunnels
If you asked an alien to design a fast single seater racer using earth’s technology, would it have a large and highly important, expensive and complex front wing? No and far from it. To find the most natural, simple way of a car producing high amounts of downforce with as little cost and drag as possible you have to go back in time to 1977. Legendary Lotus founder Colin Chapman had been studying aerodynamics at the British jet fighter manufacturer De Havilland. Aerodynamics had already come to importance over 10 years ago when ‘wings’ appeared on racing cars. Wings are in fact upside down aircraft wings. Instead of producing lift the wing produces downforce, pushing the car into the ground and producing grip and speed. Colin was further inspired by fluid dynamics and how they worked on De Havilland’s ‘Mosquito’ fighter aircraft. He came to realise that the underside of the car could be profiled into a curve, similar to a wing face. Plastic brushes and later rubber around the edge of the cars floor created ‘skirts’ which stopped air interfering with this large area of low pressure. The ‘Venturi’ affect as it is called would basically turn the entire car into a wing, sucking it to the ground. His ideas were relayed back to his designers Peter Wright, Martin Ogilve, Tony Rudd and Ralph Bellamy. Penned as the ‘Lotus 78’, a new car was born out of these ideas and principles. The front wing was small and skinny and all that was required to address balance and allow the underside of the car to work optimally.  Sculptured after many hours in Imperial College London’s wind tunnel, the result was in my eyes the most beautiful car to ever grace a racing circuit. 
The Lotus 79 changed motorsport forever
Introduced for the Argentinian Grand Prix in 1977 the benefits were obvious and the cornering speeds were phenomenal. Unfortunately the grip was being generated so far forward in the car that a huge rear wing was required to keep the back end in check. This meant the car suffered on the straights with drag. This coupled with an underpowered and over worked Cosworth DFV it wasn’t enough to top the season and the team finished the constructors championship 2nd. Efforts went into reducing the rear wing size and tendency to oversteer for the new much more rounded '79'. That went on to win 9 of the 15 races and won the World Championship with Mario Andretti.  A successful year was marred by the death of the talented team mate Ronnie Peterson, succumbing to injuries sustained from an off-line pile up at the Italian Grand Prix. It would prove to be Team Lotus’ last World Championship and it wasn’t long until the rest of the field cottoned onto the advantages of ground effect. However many teams did not have the budget for wind tunnel testing and the results were crude applications often with undesirable side effects. Disturbances in the airflow under the car would cause cars to ‘porpoise’ or rock back and forth. This could often be violent and was particularly uncomfortable for the driver as the cars had to be run on rock hard suspension to maximise efficiency. At times the cars could lose their ground effect and grip in an instant with scary results.

 ‘To be honest, there was no such thing as cornering technique in the ground effect era.  “Cornering” was a euphemism for rape practised on the driver. . . When you came into a corner you had to hit the accelerator as hard as you possibly could, build up speed as quickly as possible and, when things became unstuck, bite the bullet and give it even more. In a ground effect car, reaching the limit was synonymous with spinning out.’ – Niki Lauda

1982 proved a dangerous season
FISA were worried with cornering speeds and teams experimenting with ground effect with very little aerodynamic knowledge. Skirts could break sending cars off the track at high speeds. Patrick Depailler was killed testing for the German Grand Prix in 1980. While the accident was blamed on suspension failure and poor guard rails the car was travelling at significant velocity at the high speed Ostkurve, thanks to ground effect. The following year skirts were banned by FISA but teams had other ideas such was the advantage. Skirts that dropped out on circuit but retracted to hide from scrutineering were developed and FISA lifted the ban in 1982. Cars continued to have accidents at very high speeds with legend Gilles Villeneuve losing his life at Zolder in Belgium. Although not the cause of Villeneuve’s death, again the high speed of the cars played a factor. Turbo engines were beginning to appear in F1 and were looking to make a scary combination. Villeneuve’s team mate Didier Pironi suffered a horrific crash at the German Grand Prix were the ground effect of the cars in front had thrown up a fog like mist from the wet race track. Unsighted Pironi smashed into the back of Alain Prost’s Renault severely injuring his legs, surviving but ending his career. Across the pond Gordon Smiley lost his life in an horrific high speed accident in his ground effect car at the Indy 500. FISA had enough and made a flat under tray under cars which effectively banned ground effect from Formula One. While it continued 

Today in principle we still have ground effect but at a very restricted level, with the diffuser at the rear of the car. Bring back unrestricted ground effect with today’s understanding of aerodymanics would result in the drivers having to wear G suits – the cornering speeds would be ridiculous and highly dangerous. However remove the complex over body aerodynamics and the over reliance on the front wing and you have the potential for some great racing. Limitations, be it on tyre compound and some clever restrictions on the ground affect area would bring the cornering speeds down to acceptable levels. This wouldn’t be the highly explosive twitchy cars of old. Ground effect can now be applied with modern safety standards. The band aid of DRS would be redundant and even road cars would benefit from the most efficient way of producing grip in this age of efficiency.

Now it looks like the F1 circus is starting to see sense, with proposals for ground affect for 2017 up for discussion by the Strategy Group.  Jenson Button supports the notion, “if you’re going to work with downforce it should come from the floor rather than the wings, because you can race closer and fight, and you don’t have as much dirty air from the wings for the car following,”   

Let’s hope the proposal makes some serious inroads. In 2012 the idea of ground affect was thrown out the window with teams stating their worry over costs. The reality was the dominant and powerful teams in the sport at the time, namely Redbull and Ferrari, didn’t want the pecking order shaken up by a fundamental redesign. You can be ensured after this initial investment the costs of development would be slashed ­­­­. Bring it back I say…

Elio De Angelis at the French Grand Prix 1982

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