Performance
As well as being fast in a straight line, F1 cars also have incredible cornering ability. Grand Prix cars can negotiate corners at significantly higher speeds than other racing cars because of the intense levels of grip and downforce. Cornering speed is so high that Formula One drivers have strength training routines just for the neck muscles . Former F1 driver Juan Pablo Montoya claimed to be able to perform 300 reps of 50 pounds with his neck. Since most tracks are clockwise, most drivers have the neck muscles built up on one side of their neck[citation needed], thus making counter-clockwise tracks (such as Imola, Istanbul Park and Interlagos) a much more testing race than even the high speed Monza or the tight and narrow Monaco.
The combination of light weight (605 kg in race trim), power (950 bhp with the 3.0 L V10, 730 bhp (544 kW) with the 2007 regulation 2.4 L V8), aerodynamics, and ultra-high performance tyres is what gives the F1 car its performance figures. The principal consideration for F1 designers is acceleration, and not simply top speed. Acceleration is not just linear forward acceleration, but three types of acceleration can be considered for an F1 car's, and all cars' in general, performance:
- Forward acceleration
- Forward deceleration (under braking)
- Turning acceleration (centripetal acceleration)
All three accelerations should be maximized. The way these three accelerations are obtained and their values are:
Forward acceleration
The 2006 F1 cars have a power-to-weight ratio of 1,250 hp (932 kW)/tonne (0.9 kW/kg). Theoretically this would allow the car to reach 100 km/h (62 mph) in less than 1 second. However the massive power cannot be converted to motion at low speeds due to traction loss, and the usual figure is 2 seconds to reach 100 km/h (62 mph). After about 130 km/h (81 mph) traction loss is minimal due to the combined effect of the car moving faster and the downforce, hence the car continues accelerating at a very high rate. The figures are (for the 2006 Renault R26):[citation needed]
0 to 100 km/h (62 mph): 1.7 seconds
0 to 200 km/h (124 mph): 3.8 seconds
0 to 300 km/h (186 mph): 8.6 seconds*
*Figures may alter slightly depending on the aerodynamic setup.
The acceleration figure is usually 1.45 g (14.25 m/s²) up to 200 km/h (124 mph), which means the driver is pushed back in the seat with 1.45 times his bodyweight.
Deceleration
The carbon brakes in combination with tyre technology and the cars aerodynamics produce truly remarkable braking forces. The deceleration force under braking is usually 4 g (39 m/s²), and can be as high as 5-6 g when braking from extreme speeds, for instance at the Gilles Villeneuve circuit or at Indianapolis. In 2007, Martin Brundle, a former Grand Prix driver, tested the Williams Toyota FW29 Formula 1 car, and stated that under heavy braking he felt like his lungs were hitting the inside of his ribcage, forcing him to exhale involuntarily. Here the aerodynamic drag actually helps, and can contribute as much as 1.0 g of braking force, which is the equivalent of the brakes on most sports cars. In other words, if the throttle is let go, the F1 car will slow down under drag at the same rate as most sports cars do with braking, at least at speeds above 150 km/h (93 mph). The drivers do not utilise engine or compression braking, although it may seem this way. The only reason they change down gears prior to entering the corner is to be in the correct gear for maximum acceleration on the exit of the corner.
There are three companies who manufacture brakes for Formula One. They are Hitco, (based in the US, part of the SGL Carbon Group), Brembo in Italy and Carbone Industrie of France. Whilst Hitco manufacture their own carbon/carbon, Brembo sources theirs from Honeywell, and Carbone Industrie purchases their carbon from Messier Bugatti.
Carbon/Carbon is a short name for carbon fibre reinforced carbon. This means carbon fibres strengthening a matrix of carbon, which is added to the fibres by way of matrix deposition (CVI or CVD) or by pyrolosis of a resin binder.
F1 brakes are 278 mm (10.9 in) in diameter and a maximum of 28 mm (1.1 in) thick. The carbon/carbon brake pads are actuated by 6-piston opposed calipers provided by Akebono, AP Racing or Brembo. The calipers are aluminium alloy bodied with titanium pistons. The regulation limits the modulus of the caliper material to 80GPa in order to prevent teams using exotic, high specific stiffness materials for example Beryllium. Titanium pistons save weight, and also have a low thermal conductivity, reducing the heat flow into the brake fluid.
Lateral acceleration
As mentioned above, the car can accelerate to 300 km/h (190 mph) very quickly, however the top speeds are not much higher than 330 km/h (205 mph) at most circuits, being highest at Monza 360 km/h (224 mph), Indianapolis (about 335 km/h (208 mph)) and Gilles Villeneuve (about 325 km/h (202 mph)). This is because the top speeds are sacrificed for the turning speeds. An F1 car is designed principally for high-speed cornering, thus the aerodynamic elements can produce as much as three times the car's weight in downforce, at the expense of drag. In fact, at a speed of just 130 km/h (81 mph), the downforce equals the weight of the car. As the speed of the car rises, the downforce increases. The turning force at low speeds (below 70 to about 100 km/h) mostly comes from the so-called 'mechanical grip' of the tyres themselves. At such low speeds the car can turn at 2.0 g. At 210 km/h (130 mph) already the turning acceleration is 3.0g, as evidenced by the famous esses (turns 3 and 4) at the Suzuka circuit. Higher-speed corners such as Blanchimont (Circuit de Spa-Francorchamps) and Copse (Silverstone Circuit) are taken at above 5.0g, and 6.0g has been recorded at Suzuka's 130-R corner. This contrasts with 1g for the Enzo Ferrari, one of the best racing sports cars.
These turning accelerative forces allow an F1 car to corner at amazing speeds. As an example of the extreme cornering speeds, the Blanchimont and Eau Rouge corners at Spa-Francorchamps are taken flat-out at above 300 km/h (186 mph), whereas the race-spec touring cars can only do so at 150–160 km/h (note that lateral acceleration increases with the square of the speed). A newer and perhaps even more extreme example is the Turn 8 at the Istanbul Park circuit, a 190° relatively tight 4-apex corner, in which the cars maintain speeds between 265 km/h (165 mph) and 285 km/h (in 2006) and experience between 4.5g and 5.5g for 7 seconds - the longest sustained hard cornering in Formula 1.
Top speeds
Top speeds are in practice limited by the longest straight at the track and by the need to balance the car's aerodynamic configuration between high straight line speed (low aerodynamic drag) and high cornering speed (high downforce) to achieve the fastest lap time. During the 2006 season, the top speeds of Formula 1 cars were a little over 300 km/h (186 mph) at high-downforce tracks such as Albert Park, Australia and Sepang, Malaysia. These speeds were down by some 10 km/h (6 mph) from the 2005 speeds, and 15 km/h (9 mph) from the 2004 speeds, due to the recent performance restrictions (see below). On low-downforce circuits greater top speeds were registered: at Gilles-Villeneuve (Canada) 325 km/h (203 mph), at Indianapolis (USA) 335 km/h (210 mph), and at Monza (Italy) 360 km/h (225 mph). In the Italian Grand Prix 2004, Antônio Pizzonia of BMW WilliamsF1 team recorded a top speed of 369.9 kilometers per hour (229 mph).
Away from the track, the BAR Honda team used a modified BAR 007 car, which they claim complied with FIA Formula One regulations, to set an unofficial speed record of 413 km/h (257 mph) on a one way straight line run on 6 November 2005 during a shakedown ahead of their Bonneville 400 record attempt. The car was optimised for top speed with only enough downforce to prevent it from leaving the ground. The car, badged as a Honda following their takeover of BAR at the end of 2005, set an FIA ratified record of 400 km/h (249 mph) on a one way run on 21 July 2006 at Bonneville Salt Flats. On this occasion the car did not fully meet FIA Formula One regulations, as it used a moveable aerodynamic rudder for stability control, breaching article 3.15 of the 2006 Formula One technical regulations which states that any specific part of the car influencing its aerodynamic performance must be rigidly secured.
Recent FIA performance restrictions
In an effort to reduce speeds and increase driver safety, the FIA has continuously introduced new rules for F1 constructors since the 80s.
These rules have included the banning of such things as the "wing car" (ground effect) in 1983, the turbo in 1989, active suspension and traction control in 1994, the introduction of grooved tyres in 1998 and the reduction in engine capacity from 3.0 to 2.4 litres in 2006. Yet despite these changes, constructors continued to extract performance gains by increasing power and aerodynamic efficiency. As a result, the pole position speed at many circuits in comparable weather conditions dropped between 1.5 and 3 seconds in 2004 over the prior year's times. In 2006 the engine power was reduced from 950 bhp (710 kW) to 750 bhp (560 kW) by going from the 3.0 L V10s, used for over a decade, to 2.4 L V8s. These new engines are capable of achieving over 20,000 rpm. The aerodynamic restrictions introduced in 2005 were meant to reduce downforce by about 30%, however most teams were able to successfully reduce this to a mere 5 to 10% downforce loss. For the 2007 season, teams were not allowed to make modifications to the engines and they were limited to 19,000 rpm.
In 2008, the FIA has further strengthened its cost-cutting measures by asking that gearboxes are to last for 4 grand prix weekends in addition to the 2-race engine lives. Further, all teams are required to use a standardised ECU supplied by MES (McLaren Electronic Systems) made in conjunction with Microsoft. These ECUs have placed restrictions on the use of electronic driver aids such as Traction Control and engine braking. The emphasis being on reducing costs as well as placing the focus back onto driver skills as opposed to the so-called 'electronic gizmos' controlling the cars.
Changes for the 2009 season included a return to slick tyres, considerable reduction in aerodynamic grip via the banning of winglets and other aero devices previously used to better direct airflow over and under the cars and a drop in maximum engine rpm down to 18,000.
Due to increasing environmental pressures from lobby groups and the like, many have brought into speculation the relevance of Formula 1 as an innovating force towards future technological advances (particularly those concerned with 'greener' cars). The FIA has been asked to consider how it can persuade the sport to moving down a more environmentally friendly path. Therefore, in addition to the above changes outlined for the 2009 season, teams were invited to construct a KERS (Kinetic Energy Recovery System) device, encompassing certain types of regenerative braking systems to be fitted to the cars in time for the 2009 season. The system aims to reduce the amount of kinetic energy converted to waste heat in braking, converting it instead to a useful form (such as electrical energy or energy in a flywheel) to be later fed back through the engine to create a power boost. However unlike road car systems which automatically store and release energy - the energy is only released when the driver presses a button and is artificially limited to 400kj per lap - effectively mimicking the "Push to pass" button from Indycar and A1GP series. No teams will be using KERS in 2010. Such technology is highly likely to become a staple in the design and construction of road cars within the next 10 to 15 years, with increasing fuel costs and environmental concerns. It is through these technological breakthroughs that Formula 1 is striving to not only be the peak of what is technically possible, but also a platform from which environmentally friendly solutions for future use may be obtained, in a similar way to the development of technologies that have improved performance and efficiency in ordinary vehicles in the past.