The 2009 regulations explained

Front wings will be adjustable. A driver will have multiple options (up to three degrees either way) and can choose an option setting once per lap, after which he must return to the baseline setting. This feature will allow a driver to compensate for front downforce lost when following another car, which should enhance his chances of overtaking. It will be regulated by the standard ECU.

Rear wings must be 75% narrower than in 2008 and 150mm higher. The rear diffuser, which assists with airflow under the car, is moved 330mm rearwards. This reduces downforce and limits the disruptive effect on the performance of a following car.

Aerodynamic add-ons, such as barge boards, turning vanes and winglets, are banned. This reduces downforce.

Bridgestone will supply slick tyres for 2009, replacing the grooved rubber used since 1998. This increases mechanical grip and will increase some cornering speeds.

Engines must last for at least three complete Grand Prix weekends, excluding Friday practice, or the driver faces a penalty. In total each driver is limited to eight engines for the season. In 2008, engines lasted for two races and the extension of engine life is designed to reduce costs.

Engine revs will be limited to 18,000rpm, down from 19,000rpm, while development of internal components is further restricted.

Kinetic Energy Recovery Systems (KERS) can be used. The optional KERS device takes energy generated under braking and re-uses it as a power boost, limited to 400kJ per lap. This equates to around 80hp for around 6.5secs a lap.

Testing outside of a Grand Prix weekend has been banned after the first race of the season. In a further cost saving measure, wind tunnel testing is limited to 60% models with speeds of no greater than 50 metres per second.

To reduce costs, Formula 1 factories must close for a total of six weeks during the year while teams will share tyre and fuel information at Grands Prix to enhance efficiency.

In addition, manufacturers, including Toyota, have agreed to provide an engine supply to independent teams for approximately 50% of the 2008 costs.

Chassis

Formula 1 has initiated a major change in aerodynamic regulations for 2009 with three clear goals: to make overtaking easier; to limit the constant increase in speeds and to make the cars' appearance cleaner.

When the sport's top engineers met to establish the 2009 aerodynamic rules, they proposed a 50% cut on 2006 downforce levels to achieve overtaking and speed reduction targets. Advances in aerodynamic techniques in conjunction with ceaseless work from engineers have limited this reduction but downforce levels this year will nevertheless be considerably lower than in 2008.

The wide-ranging changes have significantly altered the appearance of Formula 1 cars in 2009, with the most striking difference being changes to the front and rear wings. At 1800mm, front wings are wider and 75mm lower while rear wings are 75% narrower at 750mm, with the amount of development allowed in these areas further restricted. As well as reducing downforce and hence cornering speeds, these changes are focused on increasing a driver's chance to overtake the car in front.

Senior General Manager Chassis Pascal Vasselon explains: "The aim is to make the cars less aerodynamically-sensitive to the wake of the car in front; that is the air disturbance immediately behind a car travelling at speed."

Another aerodynamic change sees the removal of additional devices such as barge boards, turning vanes and winglets, which contributed a significant amount of downforce. On a 2008 car, the bargeboards alone accounted for around 10% of downforce, so the adverse affect on lap time should not be underestimated, and this was a primary motivation behind the change. In addition, this change also gives the 2009 cars a cleaner, simpler appearance.

As Pascal reveals, these devices evolved out of necessity: "We worked within what we call ‘legality boxes'. These were specific areas of the car where additional downforce-generating devices were permitted. Their location was not driven purely by physics."

A key difficulty facing drivers trying to overtake in Formula 1 is the front downforce lost when following another car, due to air disturbance. The revised wings address this to an extent but a further solution is the movable front wing. In order to recover some of that lost front downforce, a driver can change the angle of his front wing once per laps, thus generating an increase in downforce.

Pascal adds: "The team defines a baseline setting before the race and the driver then has the possibility to define which option he would like, using a switch, and with a push of a button he can enact the change. But he must always return to the baseline setting, so every second change returns the wing to its original angle."

Another move designed, in part, to make overtaking easier is the switch to slick Bridgestone Potenza tyres. After a decade on grooved tyres, which were introduced to cut cornering speeds by reducing grip, the more traditional slick tyres are back.

Slick tyres not only increase grip around corners; they also give drivers a more consistent feel when driving on the limit. The effect on overtaking comes as a result of a slightly reduced dependence on aerodynamic grip, as Pascal Vasselon says: "This changes the balance between aerodynamic performance and mechanical grip in order to limit the drop in performance suffered by the car behind."

If a driver can rely more on mechanical grip, the negative impact of air turbulence from the car in front is reduced, theoretically making overtaking easier. On the other hand, by offering increased grip, slick tyres bring extra performance, so in some cases cornering speeds could rise slightly this year, despite the downforce reductions.

The combined affect of the new regulations will likely see a slight increase in lap times due to the downforce reductions. On paper, the changes made to facilitate overtaking should also hit their targets, but whereas winter testing will immediately illustrate the cut in speeds, only the start of the racing season will vindicate the changes made to facilitate overtaking.

Engine

Formula 1's new regulations are not restricted to the chassis; far from it with two key developments introduced around the engine for 2009.

A new technology makes its debut in Formula 1 this year with the introduction of Kinetic Energy Recovery Systems (KERS). These power units re-use the energy generated by the rear wheels under braking to provide a power boost.

This year's regulations limit the amount of energy recovered and used to the equivalent of around 80hp for 6.5secs a lap; this would theoretically mean a lap time gain of between 0.1secs and 0.3secs a lap, excluding the impact of the unit's weight.

The choice of KERS system is open, with flywheel and battery technology on offer. Panasonic Toyota Racing will adopt a battery solution and development continues apace to produce a system which is both safe and performance-enhancing.

"We have worked a lot on KERS but always in a balanced way," says Executive Vice President Yoshiaki Kinoshita. "In the end it is part of the car and in our team we focus on the total performance of the car so we did not just put all our effort into KERS alone; we worked on the entire package."

While an additional power boost brings theoretically faster lap times, the additional weight of the unit potentially negates that advantage. Prior to the unveiling of the TF109, all development work was done at the team's factory for very practical reasons. Yoshiaki Kinoshita explains: "We could do 95% of the development work on the test bench, which saves the cost of taking it to the track. It will be more useful for us to test KERS for the first time in a TF109 because this is the car the unit is designed for."

Safety has been a priority from the start of the team's KERS development and dozens of team members have been trained in safe working practices around such a high-voltage device, while the unit will run on the race track only when it is proven to be safe and performance-enhancing.

The other significant development is the extension of engine life which means units must last for at least three Grand Prix weekends, excluding Friday practice, compared to two in 2008. To emphasise this change, each driver is also limited to eight engines for the whole racing season.

In order to make that reliability target more achievable, engines will be limited to a maximum of 18,000rpm; down from 19,000rpm in 2008. Thanks to the hard work of the engine department, the RVX-08 engine was 100% reliable in 2008, with no race-ending reliability issues, and that is the aim again this year with the RVX-09 unit.