Formula for Success - Aerodynamics

McLaren MP4-27 launch 2012

Formula 1's sleek racing machines look so different to the cars we see every day on the road because their design is dictated by aerodynamics.

This is the study of forces and their impact on how objects move through the air.

Can an F1 car drive upside down?

Gary AndersonBBC F1 technical analyst

"The forces reacting on an F1 car push it into the ground and make it lean on its tyres but the car doesn't care if the ground is above it - or below. So in theory the car could probably drive along upside down in the roof of a tunnel at about 120mph and it would support its own weight, which is how aerodynamics work in aeroplanes."

Hundreds of engineers working in the blue ribbon of motorsport are slaves to its principles, and teams spend millions each year chasing its rewards.

"Aerodynamics is the start, middle and the end of whether a car is quick," Lotus F1 team technical director James Allison explains.

"Generally the car with the best aerodynamics wins the championship."

The aerodynamics of an F1 car has two vital jobs on the racetrack - producing downforce and controlling drag.

Downforce pushes the car's tyres into the road and helps it travel faster through the corners.

Controlling drag - the wall of air resistance the car disturbs as it races forward - also helps increase straight-line speed.

The principles are simple but perfecting them in practice is a complex, costly and often frustrating task for the 12 F1 teams on the grid.

Aerodynamics is the start, middle and the end of whether a car is quick

First of all, the teams must play by the rules.

Each season, motorsport's governing body, the FIA, issues technical regulations with inctricate details on car design, from width and height to thickness and weight.

These strict rules on aerodynamic design, which aim to keep a lid on cornering speeds, means all F1 cars, from frontrunners like Red Bull to the backmarkers, look broadly similar.

"There are boxes which you can put things in, there are boxes that you can't," explains Gary Anderson, a former F1 car designer for Jordan, Stewart and Jaguar. "Within those boxes you can do what you want."

Exploiting the tiny aerodynamic design freedoms within the rules is painstaking, but can be the difference between seconds of extra pace on the track.

Each 10kg of downforce created is worth approximately one tenth of a second in lap time.

In pursuit of that tiny edge over their rivals, F1 teams spend millions of pounds each year and hours of brainpower on aerodynamic research.

Where does the downforce come from?

The low, wide front wing and the tall, narrow rear wing contribute roughly 60% of the car's downforce with the other 40% generated from underneath the car by its floor.

"Aerodynamics is by far the most important component of a race car so we have a big department, more than 80 people, working on this problem full-time, trying to come up with new ideas," says Allison.

"The [cost of the] aerodynamics department itself will vary from team to team but for a team that has proper ambitions of doing well you're probably looking in the region of £15m [a year].

"If you're going to steal a march on your competitors, if you're going to try and wrench yourself up the grid, you have to come up with fresh ideas and bring those to the track ahead of any of your competitors."

F1 teams use two main tools for aerodynamic research and development - wind tunnels and a computer analysis system known as computational fluid dynamics (CFD).

In the wind tunnels, which cost an estimated £32m to build, the teams use 60% scale models of a car and study the airflow over its surfaces.

Data from "runs" in the tunnel is analysed to calculate how much downforce and drag has been produced by changes made to the model.

CFD uses a virtual model of the car but operates on the same principles.

Did you know?

The exploitation of 'ground effect' downforce in the mid-1970s was both brilliant and dangerous. A shaped wing underneath the car and flexible side skirts around its side sucked it to the track. Mario Andretti won the world championship in 1978 with the famous Lotus 'wing' car. But the concept led to a huge increase in cornering speeds and a series of accidents led to ground effects being banned in 1983 and a new rule required cars to have a stepped floor.

Allison puts the importance of wind tunnel work alone in context: "The total amount of wind tunnel hours that we put into our racing cars each year is broadly similar to what a major company like Boeing or Airbus will put into the development of a new airliner that might last 30 years."

Any new aerodynamic parts or design tweaks used by F1's teams to update their cars throughout the course of a season are usually found in the wind tunnel.

Although not every redesign works on the racetrack as Ferrari found out in 2011 and 2012.

Predictions in the tunnel did not correlate with performance on track and that meant the Italian team were hampered in their fight with Red Bull for the championship.

Even innovations evolved from the tunnel to the track that do bring extra lap time - such as the double diffuser which helped Brawn Grand Prix win the 2009 title or McLaren's 'F-duct' pioneered in 2010 - are often swiftly banned, sending teams literally back to the drawing board in search of the next aerodynamic solution.

F1 first embraced aerodynamics in the 1960s when the Ferrari and Brabham teams experimented with wings.

But the 1968 Lotus, designed by legendary team boss Colin Chapman, broke new ground and captured imaginations with its aerofoils tottering precariously on high mountings from the rear suspension.

Although Lotus' innovation was banned the pursuit of aerodynamic performance continued undiminished.

"The turning point in terms of car development was when F1 realised that aerodynamics made a massive difference," sums up Gianluca Pisanello, chief engineer at Caterham F1 team.

"The cars started to have wings and then the cars themselves became wings! This is very, very exciting and my favourite thing in F1."

Reporting by Sarah Holt