By 1970, the Lotus 49, and its evolutions, remained a viable competitor, but for Colin Chapman, that success was not good enough. To a man consistently leading the way in the area of innovations, his Lotus 49 looked like an old dog. That would soon change and it would come in the form of the Lotus 72.
From the very first, even the most streamlined racing car sported a grille or radiator inlet punching a hole in the air before the rest of the car. This was understandable given most cars, even right up through the 1950s, still had their engines positioned at the front of the car. However, little would change when the engine moved to behind the driver. The cars would certainly become more compact, sleeker in every way, but they would still sport radiator inlets, albeit much more smaller and better aerodynamically profiled, at the tip of the nose.
Even considering Formula One, radiator inlets at the front of cars had been in existence since the very first race in 1950. Heading into the 1970s, it was still the same. The cars were certainly much more aerodynamically efficient and lower in their profile, but the same rules applied to car design that had been used prior to the existence of Formula One. Colin Chapman was all about breaking the rules, or at least rewriting them. And he was on the verge of doing it once again.
It would really all start in 1962 at the Lotus factory. Chapman had conceived a new idea and was in the process of taking that idea, the notion, and turning it into a reality. What would be birthed would be nothing short of revolutionary. It was the Lotus 25.
Prior to the Lotus 25 all of the Formula One cars would feature tubular framing to create the chassis of the car. However, Chapman would realize that by making a U-shaped monocoque structure that carried the cockpit, fuel tanks and engine could not only be rigid enough, but it would also sport a lower center of gravity, end up much lighter, nimble and faster.
Though there would be some teething problems with the 25, it would be by far, heads and shoulders above its competitors. As a result, the car would carry Jim Clark to an incredible seven victories over the course of the 1963 season. The 25, and a later evolution, the Lotus 33, would then earn Clark six victories in succession in 1965.
There would be other evolutions of the Lotus 25 throughout the 1.5-liter era. However, the regulations would change allowing engine displacement to increase to 3.0-liters. Lotus would have some success but just couldn't find the right engine to fit the package Chapman really had in the back of his mind.
Most teams saw the break from the smaller engines as an opportunity to bolt towards the biggest engines possible in the hopes the increased power would compensate and provide the performance needed. The drawback to this was an increase in weight, fuel usage and out-of-balance handling.
Chapman thought differently and the Lotus 49 was meant to capture those thoughts perfectly. Thankfully for Chapman, Ford would come along and agree to invest in an engine design for grand prix racing. What was surprising is that the size of the engine that would be agreed upon would be a V8. This seemed counter-intuitive at the time, but Colin knew the smaller engine enabled him to put together a tighter, lighter package with increased power. Other teams may have had more powerful engines, but the Lotus would combine very useful power with better handling and lighter weight, and therefore, would overcome the difference.
Clark would go on to prove Chapman's assumptions taking four victories over the course of the '67 season. He would then follow this up with a victory in the first round of the 1968 season as well. He likely would have earned more over the course of the season had it not been for that terrible day at the Hockenheimring. Still, Graham Hill would pick up where his teammate left off by earning two straight victories, including one in the Monaco Grand Prix, and ending the season with a third at the Mexican Grand Prix.
The Lotus 49 wasn't necessarily a revolutionary car like the 25, but it certainly made engineers stop and think. Suddenly, it wasn't just about power. In fact, lighter, more-nimble cars had the potential of great things. And if those lighter, more-nimble cars could be bolted to just the right power, the result would be tremendous. Still, the 49 followed the design tradition that had been in place for decades with the radiator opening at the front and so forth. For someone like Chapman, who was so concerned with packaging cars in the most efficient manner possible, something needed to change. Something was about to change.
The end of the 1960s saw the introduction of wings, front and rear. Aerodynamics was really beginning to make an impression in a car's handling. Chapman understood that a car's design, working in tandem with the wings, made for a much more nimble, yet stable, car. But that meant some rethinking had to take place for a car to be as efficient as possible. Chapman had tried to push with evolutions of the 49. This would result in the 56 and the 63. Neither of them would please Chapman and his expectations. So he would decide to do what he did best—design something radical.
Chapman would draw inspiration for the new design from an already existing design serving another purpose. The Lotus 56 had been developed for turbine power and racing at Indianapolis. Because of the different needs of the turbine engine, the car featured a flat, wide, wedge-shaped nose. Because the turbine engine drank fuel by the bucket-load, the car would be wider to house larger fuel tanks on either side of the driver. The overall wedge-shape of the nose and car made it very aerodynamic. Chapman would, therefore, implement this feature in the design of his new car, the 72.
The 72 would feature a very flat, wide nose. The low profile of the nose meant the radiators needed to be moved. Two small sidepods would be designed and attached to either side of the car, right beside the cockpit. This served as a mounting point for the engine's radiator. The oil cooler would be subsequently moved to behind the rear wing using the air passing out the back of the car to help cool the oil.
The departure of the radiator from the nose of the car meant Maurice Philippe, who would be in charge of taking the design in Chapman's head and turning it into an actual working car, would be able to play around with the front suspension of the car. One of the ideas he would come up with would be move the disc brakes inboard, to the inside of the nose structure of the car. This removed some weight from out at the wheels in towards the center of the car, and thereby, helped the balance and handling of the car. However, this did pose a challenge as the rotor would be bigger than the nose structure itself. The fix would be to allow the disc to protrude out of the top of the car and would put a shroud around them to aid in aerodynamics. NACA events would be used to direct cooling air into the front brakes as well.
At the rear of the car there would be some similarities. The disc brakes would be moved inboard as well. Ducts just above the suspension members then directed air to help cool them. The fuel tanks feeding the Ford-Cosworth sitting behind the driver, would still be situated within the monocoque structure to either side of the driver.
The monocoque structure, of course, would remain. However, because of the wedge-shape of the car that structure would be much lower to the ground. The monocoque structure of the 25 had seemed like a bathtub. In the 72, the driver seemed to sit atop the structure. The only real sense of protection would come in the form of a wrap-around piece of bodywork that provided aerodynamics around the driver, as well as, a mounting point for the rear-view mirrors.
Small simple wings sprouted to either side of the nose, however, the car was capable of going without the wings, like the 56. This would be done at Monza in 1970, much to Rindt's frustration and misfortune. Multiple rear wing arrangements would make appearance on the Lotus 72 as it would evolve over the course of its lifetime.
When it made its first appearance, it was clear Chapman and Philippe had revolutionized Formula One again. It would take some time but it would finally achieve the success Colin demanded when it aided Rindt earning his posthumous World Championship in 1970. Then, in happier times, the Lotus 72D, with its revised suspension, would carry Emerson Fittipaldi to the World Championship in 1972. Adorned in the John Player black and gold colors, the Lotus 72D would become one of the most iconic car in Formula One history and would forever represent modern Formula One design.
Sources: 'Lotus 72', (http://www.f1technical.net/f1db/cars/258/lotus-72). F1 Technical. http://www.f1technical.net/f1db/cars/258/lotus-72. Retrieved 12 December 2013.
'Lotus 49', (http://www.f1technical.net/f1db/cars/220/lotus-49). F1 Technical. http://www.f1technical.net/f1db/cars/220/lotus-49. Retrieved 12 December 2013.
'Lotus 25', (http://www.f1technical.net/f1db/cars/163/lotus-25). F1 Technical. http://www.f1technical.net/f1db/cars/163/lotus-25. Retrieved 12 December 2013.
'Lotus 72 Cosworth', (http://www.ultimatecarpage.com/car/276/Lotus-72-Cosworth.html). Ultimatecarpage.com: Powered by Knowledge, Driven by Passion. http://www.ultimatecarpage.com/car/276/Lotus-72-Cosworth.html. Retrieved 12 December 2013.
Wikipedia contributors, 'Lotus 56', Wikipedia, The Free Encyclopedia, 18 November 2013, 20:00 UTC, http://en.wikipedia.org/w/index.php?title=Lotus_56&oldid=582253934 accessed 13 December 2013 By Jeremy McMullen