Launched at the second race of the 1970 season, the all new Lotus 72 was the final step from the 1950/60s cigar shape to the sharp look of the current single seaters.
The front mounted single radiator previously used was replaced by two smaller radiators mounted on either side of the cockpit. The radiators were mounted in two big fiberglass ducts, which would later be known as sidepods.
The chisel shaped nose pierced through the air much better than the rather blunt air intakes of earlier designs.
The 72 was yet another innovative design by Chapman featuring inboard brakes, side mounted radiators in sidepods, as opposed to the nose mounted radiators which had been commonplace since the 1950s and an overhead air intake. The overall shape of the car was innovative too, resembling a wedge on wheels which was inspired by the earlier Lotus 56 gas turbine car, and the layout taken from the Lotus 63 four wheel drive project testbed. The shape made for better air penetration and higher speeds. In a back-to-back test with the Lotus 49, the 72 was 12 mph faster with the same Cosworth engine.
Chapman's efforts produced one of the most remarkable and successful designs in F1 history. Taking the stressed engine layout technique from the Lotus 49 and adding advanced aerodynamics produced a car that was years ahead of its rivals. To begin with however, problems with the handling of the car had to be overcome, due to a lack of 'feel' caused by the anti-dive suspension geometry - which was designed to prevent the nose of the car dipping significantly under braking - and the anti-squat set-up at the rear, which was supposed to stop the car 'squatting down' under acceleration. Once the suspension was modified, there were no further problems. The car caused a sensation amongst the media and fans, with many people clamouring to see the remarkable car in action.
The car was introduced partway into the 1970 season, driven by Jochen Rindt and John Miles. Rindt made the car successful, winning the Dutch, French, British and German Grands Prix in quick succession. Rindt was almost certainly going to win the world championship but was killed in a qualifying crash at Monza, driving the 72 with its wings removed. His replacement, Emerson Fittipaldi won the USA race, helping Rindt become F1's only posthumous World Champion. Rindt and Fittipaldi's combined points for the season helped Lotus to its fourth constructors' championship.
The car was developed during 1971 by BRM former incumbent Tony Rudd. He worked especially on redesigning the rear suspension and modified the rear wing to produce more downforce. Fittipaldi struggled during the season but scored good results and finished a respectable sixth, whilst the following season was much better. The development work done behind the scenes helped him become the youngest world champion in F1's history in 1972 winning five races in the 72, whilst Lotus again won the constructors' championship. The car now sported a striking paintscheme of black and gold; Imperial Tobacco had introduced a new brand, and decided to increase exposure and provide more funds to Lotus as part of the deal. Lotus was now sponsored by John Player Special cigarettes. The 1973 season saw new rules introduced to increase car safety. This included mandatory deformable structure to be built into the sides of the cars, causing the 72 to be further updated with integrated sidepods, larger bodywork and new wing mounts. Fittipaldi was joined for 1973 by the brilliant Swede Ronnie Peterson. Peterson fell in love with the 72; a perfect marriage of car and driver. In his first season with Lotus, Peterson won four races, while Fittipaldi won three, but a number of retirements helped Jackie Stewart snatch the drivers' championship, although the large points tally built up by their two drivers helped Lotus keep the constructors championship. Fittipaldi left for McLaren in 1974, ironically to drive a car closely based on the 72, the McLaren M23.
This left Peterson as team leader, while Jacky Ickx joined the team to partner him. The 72 was meant to be replaced by the Lotus 76, intended to be a lighter and leaner version of the 72, but the cars' technology proved to be too ambitious and the project flopped. Lotus turned to the venerable 72 for the 1974 season. A further update to the car, increasing the front and rear track kept the car competitive. Peterson won another three races and challenged for the championship in a very closely contested season, ably supported by Ickx who turned in solid performances and scored several podiums. The now aging 72 did remarkably well for a four year old design, finishing fourth in the constructors championship but for 1975 without a replacement chassis the 72 was again pressed into service. By now it was obvious that the car, even with further modifications including a wider track and redesigned suspension was no match for the new Ferrari 312T which took the title or even the latest Brabham BT44 and Lotus finished 6th in the constructors' championship. After 20 wins, 2 drivers' and 3 constructors' championships, the 72 was retired for the 1976 season and replaced by the Lotus 77.