Lotus 79

The Lotus 79's ground effect aerodynamics were pioneered in its immediate predecessor, the Lotus 78. The undercar pressure problems in the 78 were resolved with the 79 through further design work on the venturi tunnels under the car, allowing the low-pressure area to be evenly spaced along the whole of the underside. This was achieved by extending the rear bodywork to a point inside the rear wheel suspension system, allowing the underside to extend further back rather than ending abruptly in front of the rear wheels as on the 78. The rear suspension was also redesigned to allow air to exit the rear more cleanly, enabling a smaller rear wing and lower drag. When the car first appeared, the upper bodywork was steeply raked and featured "Coke bottle" sidepods; wind tunnel work showed these unnecessary given the car's downforce levels. These features were later incorporated into the Lotus 80.

Five chassis were built during the design's lifetime. The prototype 79/1 was later sold to Héctor Rebaque to race as a privateer entrant.

The car was powered by the Ford Cosworth DFV and constructed of sheet aluminium honeycomb, specially strengthened for the pressures exerted by ground effect. The fuel tank was a single cell behind the driver, unlike the separate tanks on the Lotus 78; this improved fire protection and returned the centre of gravity to the middle of the car, aiding cornering and braking. The 79 was also the first Formula One car to be designed using computer design aids and the first to use computers to analyse it in the pits during race weekends.

The car was secretly tested in late 1977 by Ronnie Peterson and proved extremely fast, but the chassis suffered early fatigue from the severe suction and g-forces generated by the ground effect — about 30% more downforce than the 78, something not foreseen by Ogilvie and Rudd. The chassis was then strengthened around the monocoque and load-bearing points. Despite the improvements, the monocoque tub was never as stiff as the team would have liked, requiring new castings several times during the two seasons the car was used. The exhaust also had a tendency to overheat, and Mario Andretti had reservations about the brakes, which faded noticeably over a race distance especially in hot conditions.

Nicknamed "Black Beauty" by the press and fans for its sleek profile and black-and-gold livery through sponsorship by John Player Special cigarettes, the Lotus 79 was instantly competitive on its debut.

The 79 debuted at the 1978 Belgian Grand Prix at Zolder. Andretti took pole position by more than a second and won the race comfortably. Peterson, after scoring an impressive pole position at one event, quipped that the car was so brilliantly set up all he had to do was steer.

The team had already won in Argentina with Andretti and South Africa with Peterson using the Lotus 78. The 79 was first used during practice for the Monaco Grand Prix with Andretti driving, but he raced the 78 there. At the Belgian Grand Prix it was ready with one car for Andretti while Peterson used the older 78; both finished first and second respectively. The same result followed at the Spanish Grand Prix with both drivers on the 79.

At the Swedish Grand Prix, Brabham introduced the BT46B "fan car." Andretti took pole and led until Niki Lauda's fan car passed him; Andretti's engine then blew and Peterson finished third. After the race, Brabham voluntarily withdrew the BT46B. The 79 won in France with Andretti first and Peterson second. At the British Grand Prix both cars retired — Peterson from second place after seven laps with a fuel leak, and Andretti after pitting with a puncture then blowing his engine. In Germany, Andretti won while Peterson retired with gearbox failure. At the Austrian Grand Prix, Peterson won after Andretti retired following contact with Carlos Reutemann's Ferrari. Holland brought the last first-and-second finish for Lotus, with Andretti ahead of Peterson.

At the Italian Grand Prix, Andretti qualified on pole but Peterson qualified sixth and was forced to use the older Lotus 78 after his 79 suffered sudden brake failure in the warm-up and he was unable to fit into Andretti's spare car. The start was chaotic; Peterson was involved in a collision with Riccardo Patrese's Arrows and James Hunt's McLaren. Peterson's car caught fire and Hunt dragged him free. Peterson underwent an operation but died the following Monday, with severe leg injuries. Andretti restarted and was first on the road but finished sixth after both he and Gilles Villeneuve were penalised for jumping the restart. In the United States, Jean-Pierre Jarier took over the second Lotus seat and ran third until he ran out of fuel with four laps to go; Andretti led early but suffered a brake issue and later a blown engine. At the Canadian Grand Prix, contact with John Watson's Brabham dropped Andretti to the back; Jarier took pole and led until an oil leak ended his race.

Andretti was comfortably world champion in 1978, and Peterson finished runner-up posthumously. Lotus won the constructors' championship with 86 points. The only real threats had been the Ferrari 312T3, whose Michelin tyres gave an advantage in hot conditions, and the Brabham BT46B; the Ferraris only won when the Lotus failed to finish.

For 1979, Lotus kept Andretti and recruited Reutemann as second driver. Martini Racing replaced John Player Special as sponsor, so the car appeared in British racing green after twelve years of black and gold. The 79 was intended to be replaced by the Lotus 80, the next step in the evolution of ground effects, but unlike the two previous models the 80 proved a total failure, forcing Lotus to revert to the 79 for both drivers. Several podium places were scored and the 79 was in contention for victory early in the season, but the next generation of ground effects cars — led first by the Ligier JS11, then the Ferrari 312T4, then the Williams FW07, a car heavily based on the 79 — outclassed the Lotus. Revised bodywork and a new rear wing were fitted, but Lotus slipped to fourth in the constructors' championship and the 79 was retired at the end of the 1979 season without winning any further races.

In December 1979, the car gave Nigel Mansell his first Formula One test, at Paul Ricard.

This article is based solely on the supplied corpus. No external sources were consulted; claims that could not be substantiated against the corpus were omitted under the drop-the-claim rule.