There are few things in life as thrilling a live Formula one race. The speed and roar
of the engines sends adrenaline pumping through yours veins, but this isn’t just mere entertainment.
Racing at the highest level tests engineers and drivers in ways that normal production
cars do not and forces them to think of clever and innovative ways to improve performance.
These technologies have on multiple occasions found their way into our everyday lives. There
are countless examples of this happening since the birth of competitive racing.
The first reliable steel disk brake was produced for the Jaguar C-Type in 1953. The exposed
disk brake allows the brake to shed the heat generated in breaking much more effectively
than the drum brake and allows stopping distances to decrease. This technology helped the Jaguar
C-Type to reduce wear on the break and reduce braking distances,allowing it to take 3 of
the 4 top places in the 1953 24 Hour Le Mans and has since saved thousands of lives in
the real world, due to their superior braking and reliability. Over the course of the 24
hour race many of their competitors had to drop out of the race because their brakes
were disintegrating. The improved breaks also meant that the drivers could break much later
into a turn and thus post much quicker laps.
Racing technologies are always a few steps ahead of production cars, but these technologies
generally trickle down over time as costs reduce. Carbon fibre is probably going to
be the next great innovation in car manufacturing. All F1 cars use carbon reinforced composite
brake disks which save weight and are capable of operating at higher temperatures than steel
disks, but you will rarely see such high end materials in normal everyday cars. The material
was first used in the monocoque of F1 cars in 1981 when McLaren unveiled the MP4/1. The
material had been used for small parts previously, but some engineers doubted it’s ability
to withstand a crash. That all changed when John Watson crashed his McLaren at the Monza
Grand Prix and came away uninjured. John Watson himself doubts that he would have been so
lucky if he had been driving in a traditional aluminium frame.
After that day the other racing teams were playing catch up and now every F1 car uses
the material. Carbon fibre has slowly found it’s way from high-end racing cars to production
cars thanks to car manufacturers like BMW who have made huge investments in manufacturing.
Carbon fibre production has typically been incredibly expensive due to the vast energy
required but BMW invested invest 300 million into a hydro-powered carbon fibre manufacturing
plant in Moses Lake, Washington with the aim to produce 9000 tonnes of the material per
year exclusively for their cars. This increase in production quantity reduced the prices
enough to make it viable for production cars like the BMW i3 and i8, which have an all
carbon fibre reinforced plastic frame (wrong word). Carbon fibre is becoming more and more
common and we can expect to see it gradually replacing metal parts in our transport because
it reduces weight and thus reduces energy consumption, while also being incredibly strong.
It has even found it’s way into our passenger planes with the Boeing 787 dreamliner and
Airbus A350 XWB being primarily made from composite materials, but more on that in my
next video.
These examples go on and on but today we are going to focus on the leaps in our understanding
of automotive aerodynamics as a result of competitive racing. Some of the most talented
aerodynamicists in the world work for modern day F1 teams and the lessons they learned
through racing has helped improve the efficiency of our cars immensely. Allowing them to cut
through the air effortlessly, drive faster and use less fuel, but it wasn’t always
this way. In the early days of competitive racing there
wasn’t really any distinction between race cars and street cars, they only discernible
difference was in the lunatics that were to driving them. The distance between the left
and right wheels were narrow and the centre of gravity of the cars were high, making the
cars incredible unstable in turns and susceptible to roll overs....
Early sports racing cars were typically light weight front engined vehicles and their designers
understood the basic concept of drag. The engines at their disposal were relatively
low powered and inefficient and so to counteract this they made their cars as round and streamlined
as possible to reduce the effects of drag. Drag is defined by this equation:
Where Rho, which is the greek letter that looks like a p represents the density of the
fluid the object is moving through, v is the velocity, C is the coefficient of drag which
is a property defined by the shape of the object and A is the cross sectional area of
the object.
You can see from this equation, that the drag force increases dramatically as the speed
of the car increases because the velocity is squared. That is why to gain even a tiny
bit of speed at the higher levels of racing huge amounts of additional horsepower are
required. This is why these early designers focused so much on lowering the drag for their
low horsepower vehicles. The coefficient of drag for a circle is just 0.47, while a square
is 1.05. So by rounding a shape we can reduce the drag by more than half. And if we decrease
cross-sectional area by half we can reduce the drag by half again. So it’s clear why
the shape effects the performance of the car so much.
This equation is useful for understanding how drag works, but the designers were not
getting a full picture of what was happening to the air around their cars, because they
had essentially just designed aerofoils that were capable of producing lift. At best this
reduced the car’s ability to transfer power from the tires to the ground at worst it made
the car begin to lift off the ground and crash. .
One of the first people to realize and attempt to correct this problem was a young Swiss
engineer and driver called Michael May. He recognised the potential of using an aerofoil
to create negative lift and thus push the car down towards the ground, thereby improving
traction, grip and handling of his car. So he modified his Porsche Type 550 by mounting
this huge inverted wing over the cockpit. The wing proved so successful that it beat
all other Porches in it’s first race in 1956 at the Nürburgring 1000 Kilometre race,
this drew criticism from the Porsche’s factory team and they pressured the race organizers
to ban the wing on the grounds that it blocked the view of the drivers behind him. This incident
stalled the development of downforce generation, but the idea was too good to go unnoticed
for too long.
In 1963 Jim Hall mounted an adjustable wing onto his Le Mans winning Chaparral 2E. He
understood that downforce was essential to keep his car glued to the road, but also recognised
that it added drag. So he made this wing controllable, this way it could be made horizontal to reduce
drag on long straight sections of the track and lowered when entering turns.This was the
first of it’s kind and the idea was quickly adopted by Formula 1 teams, but these high
mounted movable wings were poorly engineered and after a series of breakages they were
banned completely. But the automotive world had hit a tipping point. The idea could no
longer be ignored and manufacturers began to design entire cars around this concept
rather than just going for the most aerodynamic shape possible.
There is no better example of this than the evolution of the Porsche in the late 60s.
Porsche has made a name for itself as a giant killer with it’s sleek, low drag roadsters
that were managing to beat much more powerful Ferraris and Maseratis, but as the company
grew Porsche decided to design a new high horsepower racing engine and build an innovative
body around it and thus the iconic Porsche 917 was born.
It’s birth was not without it’s share of difficulties. Early on it was plagued with
aerodynamic instability. This new formula of high power and low drag was a new concept
to Porsche and it took them some time to perfect it, but they gradually reprofiled the body
work and the 917 began to dominate races in the early 70s.
This progression hit a boiling point with the accidental discovery of ground effect
with the Lotus Type 78. During the development of the Type 78 the head engineer Peter Wright
and his team were experimenting with prototypes of a new design for aerofoil sidepods in the
Imperial College London wind tunnel. Over the course of the day the rudimentary prototype
wings began to sag towards the ground of the wind tunnel and to the amazement of the team
there was a huge increase in downforce. Initially they didn’t understand what was causing
the increase, but soon discovered that by adding cardboard skirts to the sidepods air
was being forced and trapped beneath the car and as we have discussed in previous videos,
when air is forced through a constriction it experiences an increase in speed and a
decrease in pressure. This is called the Venturi Effect. They later developed these brush skirts
that sealed the air under the car, which were later replaced with rubber skirts.
This low pressure air relative to the high pressure air flowing over the car caused a
huge increase in downforce with only a marginal increase in drag, making the car stick to
road in corners and reach incredible speeds on the straights. This was the holy grail
of aerodynamic discovers and all Formula One cars since have followed this design principle.
The Lotus Type 78 set the standard for what we see today. The successor to the Type 78,
the Type 79 was so dominant that teams like Brabham had to think of even better ways of
achieving that ground effect phenomenon. The Brabham BT46, is probably one of the most
controversial cars to ever hit an F1 track. Teams were struggling to keep up with the
Type 79 and Brabham’s team led by Gordon Murray were trying to figure out ways of beating
it. Gordon Murray was reading through the rulebooks when he noticed a loop hole. The
rules stated that cars with moveable devices that were primarily used for aerodynamic advantages
were not allowed, but he realised that if he could make an argument for a new device
being used primary for cooling then they could use a fan that sucked air from the bottom
of the car and ran it through the engine. The energy of this system would primarily
be used to cool the engine, but it had the added bonus of sucking the car onto the road.
The Brabham BT46 and Lotus Type 79 faced off in the 1978 Swedish Grand Prix and despite
complaints from Colin Chapman, the founder of lotus, the fan car still ran. Mario Andretti,
driving for Lotus took an early lead, but the Brabham driven by Niki Lauda was gradually
gaining and eventually overtook Andretti on the outside. Niki Lauda and the Brabham BT46
went on to win the race by 34 seconds, but this would be the fan cars first and final
competitive race. Other drivers complained that the car was firing rocks and dusts out
the back and despite the car being within the regulations the other teams pressured
the FIA to outlaw the car. Brabham were told they could run the car for the rest of the
season, but instead decided to withdraw, leaving the door open for Lotus to win the 1978 Formula
One season. The following year Lotus slipped to fourth place as other teams caught up with
ground effect technology. I think this exemplifies why I enjoy racing, for me it’s less about
the drivers and more about the engineers behind them competing to create the best vehicle
possible within the rules.
Today engineers have a huge amount of tools at their disposal to rapidly prototype new
car bodies. I mentioned that the Type 78 was tested in a wind tunnel and that testing helped
towards the discovery of ground effects, but prototypes are time consuming to make and
wind tunnels aren’t always available to everyone. One of the biggest developments
in F1 and engineering in general in the past 2 decades has been the advancement of computer
aided engineering. With this method we can simply generate a huge variety of models and
test all of them in a short space of time to quickly figure out which design is best.
The animations you are seeing on screen right now are actual engineering simulations that
accurately depict the airflow over an F1 car. I have teamed up with SimScale an online based
engineering simulation software to bring you more of these animations in future. With this
kind of power in an engineer’s hands progress can happen so much quicker and that’s lucky
because the regulations in F1 are constantly changing and challenging the design
teams behind the cars.