There are
strong reasons to believe that this car along with its predecessor the Type 78 stand as
the most significant vehicle designs in racing history.
Bernoulli’s equation, known as
one of the basics of Fluid Mechanics Theory, states the following: if fluid flows through
a constriction, its speed will rise and pressure will fall. Applied on racing car this
theory goes like this: air is a fluid. If the bottom of the car is shaped correctly, it is
possible to create a low-pressure area under the car. Car will literally be sucked to the
ground. That phenomenon is known as ‘ground-effect’. Since the cornering speed
depends on friction between tyres and tarmac, and friction depends on vertical force which
is equal to the sum of car’s weight and lift force generated by low pressure area
beneath the car; the bigger the pressure-fall is, the better the car performs.
BRM’s Tony Rudd first tested
the theory in practice, using scale models in the late 60s. However, the idea was not
pursued. March was the first to use profiled sidepods on a full-size race car in 1970. The
sidepods weren’t sealed against the ground and were situated too high to have any
effect beside not causing additional drag while making room for extra fuel needed for
thirstier races.
Brabham and McLaren experimented
with air dams beneath the car but it took some more time until, in 1977, the first proper
ground-effect car appeared: the Lotus 78 or, as it was called at the time, John Player
Special Mk. III.
Peter Wright, Colin Chapman and Tony
Rudd conceived of the idea and tested the scale model in a wind tunnel. Initial results
were incredible. The real car did not emulate the model’s values entirely, having
about ¾ of the predicted downforce but what remained was nevertheless impressive.
The car had sidepods
shaped as inverted wings thus generating downforce on both sides of the profile. The edges
were sealed against the ground with brush-like skirts, which is important to prevent
outside air from interfering with air passing beneath the car and thus spoiling the
effect. These skirts were later replaced by solid rubber skirts. The Type 78 was very
successful during 1977. Mario Andretti won 4 times and only missed the title because of
poor reliability, Gunnar Nilsson won once.
As the season progressed, Lotus
began to work on more radical car, designed to completely harness ground effect as much as
possible. By chance or by intention, it turned out to be a beautiful car, maybe the most
beautiful open-wheeler ever produced: the Lotus 79 or J.P.S. Mk. IV or Black Beauty.
It had an aluminum monocoque chassis
with arc-shaped scuttle. One giant fuel cell, permitted by new regulations, replaced three
separate cells featured on the Type 78. The Ford Cosworth DFV engine/gearbox/rear
suspension block was bolted onto the chassis’ rear end. Radiators were situated into
the leading edge of wing shaped sidepods. Front suspension was made up of lower wishbone,
top rocker arm and inboard coil spring/damper assemblies. Rear suspension consisted of
double wishbones, coil spring/damper assemblies and anti-roll bar. Front disc brakes were
mounted outboard, rear inboard, on gearbox's cheek-plates.
The engine was fully enveloped
inside the body panels while the underbody, because of the additional downforce it
generated, permitted a smaller drag-inducing rear wing.
The Type
79 was not ready for the start of the season but the old Type 78 proved to be man enough
for the job, Andretti and Ronnie Peterson scoring one win each. Andretti debuted the Type 79 in
Belgium, the sixth race of 1978 season, qualifying the car on pole, 0.79s ahead of
Reutemann’s Ferrari and handsomely winning the race. It was the beginning of a
remarkable winning streak that saw Andretti winning four more races and Peterson one, plus
a total of 9 pole positions and 5 fastest laps. Lotus won the Constructor’s title
with Andretti and Peterson taking first and second places in the drivers’
classification.
The 1978 fairy-tale was sadly
destroyed on first lap of Italian Grand Prix. Ronnie Peterson destroyed his Type 79 in
testing and, with no spare Type 79 available, had to race a Type 78. A starter’s
mistake, allowed the race to be started before all of the contenders had completely
stopped at their places, provoking a multiple incident in which Ronnie’s car hit the
guardrail head-on. Both his legs were broken and although his injuries were not thought to
be life threatening he died of post-operation complications. What should have been Lotus'
and Andretti’s celebration, since he clinched his title in Monza, turned out to be a
nightmare. There’s some amount of irony in it because the only other American World
Champion, Phil Hill, clinched his title in Monza as well, and his team-mate, von Trips,
died in that race as well.
Peterson was replaced in the team by
Frenchman Jean-Pierre Jarier. Carrying unusual start number 55 on his car he proved
79’s class by setting the fastest lap in his first race for Lotus. In the next GP he
qualified on pole and led convincingly until technical problems slowed him.
While the Lotus 79 was head and shoulders above the
opposition in 1978, being the only proper ground-effect car, Lotus was somewhat caught
sleeping at the beginning of 1979. The Type 79’s successor, the Type 80 wasn’t
ready yet and later would prove to be a flop. The team started the season with 79s painted
in Martini – British Racing Green colors, which replaced the famous black-and-gold
John Player Special livery. Carlos Reutemann partnered Andretti. The first two races fell
into Ligier’s lap for they had been by far the best-prepared team running new JS11
cars. However, the Lotuses were still the best of the rest. As the season progressed the
Lotus found themselves slipping further down the field. Mexican privateer Hector Rebaque
bought one chassis and raced it into 1980 without success.
