Revolutionary Technology in Formula One – Ground Effect

The development of the downforce-generating wing changed the course of Formula One forever, requiring a complete change in driving style and car construction to make the most of the generated downforce. No longer could drivers use flashy but inefficient drifting moves around corners; instead, precision became more and more of a factor. The generation of downforce by the wings of the car improved lap times as the tyres were used more efficiently, but there seemed to be an upper limit on how much downforce could be generated by a car’s wings before the drag effects of the wing cancelled out improvements in lap times by increasing downforce. Some enterprising team managers looked for new ways to generate downforce, ones which wouldn’t lead to drag effects cancelling out their hard work.

Just as the downforce-generating wing had been derived from aeronautical engineering, so too was the next development in downforce generation, and just Colin Chapman, legendary team owner, manager and engineer of Team Lotus, had been involved in the development of the wing, so he was instrumental to the development of automotive ground effect in Formula One. However, just as with the downforce-generating wing, the development of ground effect first came from a source outside of Formula One. Jim Hall, the Texan racing driver responsible for the Chaparral cars which had heavily influenced the development of the wing in Formula One, had also preempted developments in ground effect with the Chaparral 2J.

The Chaparral 2J was a bizarre-looking car, with a distinct and unmistakable boxy shape which seemed to completely defy all of the conventional logic on automotive aerodynamics. However, the 2J came with its own secret weapon. Two fans, driven by a two-stroke snowmobile engine mounted in the car, “sucked” the car to the surface, while flexible plastic skirts fitted to the underside of the car maintained a semi-vacuum seal which helped maintain the generated downforce from the two-stroke-driven fans.

The 2J caused great controversy in the Can-Am series in which it competed, with competitors complaining of stones thrown back by the suction fans into the faces of following drivers. The McLaren team, then dominant in the series, launched a complaint which sought to ban the fans under a law prohibiting “moveable aerodynamic devices”. Despite its significant advantages, including downforce which did not fluctuate based on the speed of the car, the Chaparral 2J was not competitively successful and suffered problems with reliability. While the 2J was capable of racing at two seconds a lap faster than its competitors, this meant little if it could not finish a race. The car raced for a single season of Can-Am in 1970, before the successful upholding of McLaren’s complaints led to the car’s banning.

The Chaparral 2J may not have been competitively successful, but other designers were researching similar concepts at the same time, trying to reduce effects such as turbulence caused by their early aerodynamic wing structures. Gordon Murray of the Brabham team managed to create useful downforce in the mid-1970s by strategic placement of air dams under the car in an attempt to prevent air flow under the car. However, like many of the developments in Formula One, Lotus were themselves doing research into the field of under-car aerodynamics.

In 1976, confronted with sub-par performance from their Lotus 77, having developed it as a replacement for their long-running and successful Lotus 72 which had nevertheless grown long in the tooth, Team Lotus redoubled their efforts on a new car. Colin Chapman, who had studied the de Havilland Mosquito fighter-bomber, one of the quickest and most successful aeroplane models of the Second World War, had realised that the wing-mounted radiators had been designed in such a way to develop lift. This, Chapman realised, could be developed in reverse in order to generate downforce, in much the same way that a reversed wing structure was then generating downforce for Formula One cars.

Having struggled in 1976 with only a single win throughout the season, Lotus fought back in 1977. The Lotus 78 was, when it worked correctly, utterly dominant, winning five races and raising Lotus from a distant fourth in the Constructors’ Championship in 1976 to second in 1977. The car owed its spectacular speed to the careful sculpting of the car’s sidepods in a way resembling an inverted aerofoil, thus creating an area of low pressure underneath the car and generating additional downforce, similar to the already-existing wings. As with the Chaparral 2J, the air was sealed under the car by the use of plastic skirts, which also had the side-effect of making it difficult for other teams to figure out where Lotus’ sudden jump in pace had come from.

Unfortunately for Team Lotus’ quest for both championships, however, the usual unreliability for Lotus cars seems to have taken hold in 1977 and despite the obvious pace, Niki Lauda’s superior reliability in the Ferrari was enough to stave off not only the challenge of Mario Andretti in the Lotus 78, but also Jody Scheckter’s challenge in the surprisingly quick car of the Walter Wolf Racing team. These reliability issues were a consequence of development versions of the Ford Cosworth DFV that was used in the Lotus 78 in an attempt to gain back some of the speed lost by some design faults of the car that caused oversteer and required a larger, drag-causing rear wing.

Nevertheless, the pace of the Lotus 78 when it went well was cause for hope and Team Lotus continued with the car into 1978. Meanwhile, the team were preparing their follow-up effort, but before this was introduced, the Lotus 78 still proved fast enough to win two of the first five races of the season, one each in the hands of Mario Andretti and Ronnie Peterson. It was after the fifth race had concluded at Monaco, however, that Team Lotus would introduce their new car, one that would prove to be as dominant in 1978 as the Lotus 78 had (on the occasions when it managed to finish) in 1977.

The Lotus 79, the first Formula One car to be designed using a wind tunnel and computer-aided design, was one of the biggest jumps forward ever seen in Formula One. If the Lotus 78 had been the revolutionary design, demonstrating what ground effect could do to the performance of a Formula One car, the Lotus 79 was the deep refinement of those principles and would overwhelmingly give Lotus both the Drivers’ Championship and Constructors’ Championship in the most dominant style then seen in Formula One. The Lotus 79 would take a further six wins for Team Lotus throughout the remainder of the season, including five for Mario Andretti on his way to the Drivers’ Championship.

The only realistic competitors that Lotus had during 1978 were Ferrari, whose 312T3 model was set up well for its Michelin tyres in hot weather conditions and Brabham, who picked up scraps in most of the races, but had one notable success in the Swedish Grand Prix. In this race, the Brabham team introduced their BT46B model, otherwise known as the “fan-car”. Gordon Murray had figured out how the Lotus team were achieving their outstanding pace, but with a car with a wide flat-12 engine which was unsuitable for manipulating the undersides of the car, the Brabham team decided to try something different.

In much the same way as Jim Hall had done with the Chaparral 2J, the Brabham BT46B developed downforce by the use of a fan fitted at the back of the car to create a partial vacuum. The results were staggering, the Brabham team cantering to an easy win, leaving even the Lotus cars in their wake. Some sources have even suggested that the Brabham cars were deliberately driven slower than they could be in order to create a semblance of fair play. In either case, the win created uproar in the paddock and fan cars were soon declared illegal from then on, with Brabham’s win still standing.

Unfortunately for Lotus, their outstanding success in 1978 was marred by the death of Ronnie Peterson near the end of the season at Monza during the Italian Grand Prix. A midfield pileup at the start of the race caused Peterson to crash with severe leg injuries. Unfortunately, as he was not judged to be in as much danger of death as others that had been injured in the shunt, he was not examined as thoroughly as he possibly should have been and later died of fat embolism in hospital. This put a damper on the celebrations for Team Lotus and Jean-Pierre Jarier was drafted in to compete in the remaining races.

After such a dominant performance, it could hardly be expected that Team Lotus would never win another championship, but 1979 was not a successful year for the team. The Lotus 80, which was to be used in the 1979 season, did not prove successful, suffering from an excess of downforce along with an effect known as “porpoising”, where the low-pressure area generated by the ground effect was moving around with the car’s centre of gravity. Indeed, this would prove to be a problem with other ground effect cars designed by less well-funded teams.

The Lotus 79 was drafted in to compete in the season, but the secret of Lotus’ success was out and other manufacturers had improved on Lotus’ designs to create ground effect cars of their own. Of these, Ferrari would be the most successful, despite their large flat-12 engine which, as with the Brabham BT46, made manipulation of the car’s underside difficult. Winning six races and scoring several podiums, Ferrari were the dominant team during 1979. Meanwhile, Team Lotus, who had dominated the 1978 season, were pushed back down to fourth place in the Constructors’ Championship, behind Williams and Ligier.

Ground effect would therefore become a constant element of Formula One cars in the next few years, but it came with its downsides. As the cars grew faster, the g-forces on the drivers grew stronger, making them less and less comfortable. Improperly understood, ground effect could cause alarming effects such as the aforementioned “porpoising” problem. With the development of turbocharged cars in the early 1980s, the cars threatened to become even faster – and would once the reliability issues were resolved – which gave the frightening notion of twitchy cars with a lot of power behind them.

Eventually, things came to a head. The 1982 Formula One season was one of the most unpredictable and tragic seasons of Formula One ever, with two drivers dead, several others injured and several dangerous incidents which could be attributed to the sudden loss of downforce when a ground effect car went over the kerbs. While neither of the deaths could be attributed to these effects – Gilles Villeneuve lost his life after a horrible crash in qualifying while chasing down his teammate’s time after the incident at the San Marino Grand Prix, while Riccardo Paletti was the victim of a start-line incident where he hit Didier Pironi’s stalled car from behind and was left stuck in a burning car when the fuel tanks suddenly went on fire – there was a sense that the season had shown too much danger and ground effect cars were promptly banned for the following seasons, being replaced with cars with flat undersides. The 1983 season would be won by a dart-shaped Brabham BT52 which starkly contrasted with the wide, squat ground effect cars of the previous years.

Today, the laws against ground effect in Formula One are strongly upheld with the addition of a wooden plank underneath the car. This is not permitted to wear down past a certain depth, effectively mandating a minimum ground clearance. However, even with the flat undersides, teams still manage to get some degree of downforce by air flowing under the car; with careful shaping of the rear diffuser and the car’s bodywork at the back, downforce can still be gained. While some racing series other than Formula One have used ground effect themselves, it would remain to be seen how much faster the Formula One cars of today would be – and how much less comfortable to drive – if ground effect had not been made illegal.

Revolutionary Technology in Formula One: Downforce-Generating Wings

As the lessons demonstrated by Colin Chapman’s use of the monocoque chassis filtered down through the rest of the Formula One grid, the cars changed shape towards a cigar-like form typified by the bodywork of the 1966 and 1967 seasons. In 1966, there was another change in the regulations, once again allowing three-litre engines which produced in the order of 350 to 400 bhp, about twice the power of the engines used from 1961 to 1965. With such a surfeit of power, the cars were unpredictable and wild, and a bit of extravagant cornering wouldn’t sacrifice too much time around a lap. Within a few years, though, both the bodywork of the cars and the driving styles had begun to change, though, as the cars began to be pushed down into the track by aerodynamic effects and driving styles became more precise in order to compensate.

As with other revolutionary developments in the world of Formula One, the changes in this period were derived from the world of aeronautics. It has, and had been known for a very long time that an aerofoil could generate lift in accordance with Bernoulli’s principle, and aeronautical engineering had progressed in leaps and bounds during the years of the Second World War. Ideas had been hopping around the Formula One paddock for years about the effect of a reversed aerofoil, which would work in the opposite way to a typical aeroplane wing, and indeed, a few minor experiments had been tried with this idea in motor racing, including Jim Hall’s experiments with the Chaparral racing cars in the mid 1960s. Unlike an aeroplane wing, which generates lift by creating a pressure differential between the longer airflow path on top of the wing and the shorter path on the bottom of the wing, an automotive wing creates downforce by reversing the pressure differential, with a longer airflow path on the bottom rather than the top.

It took until 1968 for a downforce-generating wing to find its way into Formula One. Ferrari, having apparently got over its period of conservatism which cost it development time over the early garagiste teams, and Brabham were the first teams to try the idea of placing an aerofoil onto their cars. In the 1968 Belgian Grand Prix, raced at the fast, flowing Spa-Francorchamps circuit, Ferrari used a high-strutted rear aerofoil balanced off with little tabs mounted to the front of the nosecone, while Brabham used a lower-mounted rear wing, but balanced it off with larger front winglets. While neither Brabham affected the race much, both exiting due to reliability issues, the Ferrari of Chris Amon easily snatched pole – four seconds in front of Jackie Stewart in his Matra.

Amon then set about challenging for the lead when his radiator gave up, thus ending an interesting experiment. To be fair, the Ferrari was already a quick car, with the wingless car of Amon’s teammate, Jacky Ickx, finishing third, but the proof was there that wings were a useful addition to Formula One cars. Meanwhile, Bruce McLaren took a maiden victory for his eponymous team, while other teams looked on and wondered what they could do with the new aerodynamic aids.

Lotus was, unsurprisingly, one of these teams. With Colin Chapman having an interest in aeronautical developments, and having introduced an idea found in aeroplane design into his racing cars before, it had not escaped Chapman’s attention that a reversed aerofoil could be used in this fashion, even before Ferrari and Brabham tried their own experiments. The Lotus Formula One cars soon sprouted wings, which were bolted onto the suspension and towered up into the air on thin struts in a decidedly ungainly fashion. The highly-mounted wings suffered less from turbulence than wings mounted lower down, but were, as several incidents the following year would demonstrate, highly dangerous.

By the end of 1968, Graham Hill had taken his second World Drivers’ Championship driving for Lotus, which took the Constructors’ Championship along with it. The Lotus team, with an exceptional car, powered by a refined Cosworth V8 engine and using the nascent technology of its aerodynamic aids to its advantage, made the most of a year where their top driver, Jim Clark, was killed early on in a Formula Two race and Graham Hill had to step up to the role of leading the team. More teams throughout the year had seen the advantages of downforce-generating wings, and they spread throughout almost the entire grid.

By 1969, the high-strutted rear wing of the Lotus 49B had been joined by an equally tall front wing which towered over the front suspension. Other teams, including McLaren, had similar wing layouts, but these proved problematic. The tall struts that the wings were mounted to proved fragile, as demonstrated in the practice session at the first Grand Prix of the season, held at Kyalami in South Africa, and the practice of mounting the wings to the suspension also proved troublesome. When both Lotus cars crashed out of the Spanish Grand Prix a couple of months later, downforce-generating wings were temporarily banned, only brought back when the rules were rewritten to permit low-mounted wings bolted to the chassis. The wings of today’s Formula One cars roughly resemble the layout of the later Formula One cars of the 1969 season, although they are far more evolved.

The aerodynamic expertise of the Matra team helped them win both the Drivers’ Championship, with Jackie Stewart at the wheel, and the Constructors’ Championship by significant margins. Lotus only reached third in the Constructors’ Championship, as an season of unreliability for Jochen Rindt, and several finishes out of the points for Graham Hill left them floundering. Some wasted development on the unsuccessful four-wheel drive Lotus 63 kept them from focusing their full attention on the car with more potential, although Matra and McLaren did try their own unsuccessful four-wheel drive systems, with little more success than Lotus. The aerofoil was clearly the way forward and the best way to maintain grip in a Formula One car.

Since the late 1960s, aerodynamic wings have been an omnipresent sight on Formula One cars, and have evolved from simple aerofoils to sophisticated items designed to channel the air as precisely as possible to the most efficient places to create downforce with a minimum of drag. The wings have changed shape considerably through the years, with the development of the Gurney flap, among other things. During the 1970s, large table-shaped rear wings were the norm, with some peculiar front wing designs throughout the years, while some of the cars in the early 1980s shed their front wings in the era of ground effect.

The cars of the early 1990s had noses mounted close to the ground, but by the middle of the decade, most of the front-runners had changed to a more highly-placed nose more reminiscent of today’s cars. Sculpted front wings, designed to push the air towards various critical places on the chassis, have been a notable part of recent Formula One cars. Whatever their configuration, though, the aerodynamic effects of the wings have been critical for success in Formula One almost since their first development, and they not only changed the dynamics of Formula One cars permanently, but also the appearance, as the large wings of today’s Formula One cars are their most obvious element, even to an unfamiliar spectator.