Technical analysis: Hungarian GP

The 2009 regulations did little to reduce the processional nature of the Hungarian Grand Prix, save for some KERS-assisted overtaking off the start line. The cooler than usual temperature led to tyre problems or many teams, most of whom brought slightly revised wings to the race to increase the amount of downforce.

The Massa accident

The heave damper (yellow) sits above the gearbox and its spring probably escaped through a hole in the bodywork © AUTOSPORT

The incident that preceded Massa's crash was the failure of the rear heave damper on Rubens Barrichello's Brawn. The heave spring fell out of the back of the car and onto the track, and was subsequently hit by Massa at 162mph.

The rear heave damper, or 'third damper' as it is more often called, has been common on F1 cars since active suspension was banned. It sits above the gearbox, between the pushrods of the rear suspension and acts to control the up-and-down motion of the rear of the car. This motion is known as heave, hence the term applied to the device.

Teams use springs, dampers or bump rubbers to control the motion, but it's the spring that is used to prevent the rear of the car squatting at high speed when the downforce is trying to compress the rear suspension. The spring is usually made from steel or titanium and weighs around 800g.

The bolt which mounted the damper on Barrichello's car failed, allowing the spring to break free. It probably made its way out of the rear of the car through the cooling holes Brawn has cut into the teardrop-shaped bulges above the rear suspension. The Brawn has quite enclosed bodywork, whereas some teams totally enclose this area with a separate fairing and teams such as Williams, BMW and Force India have the rear bodywork fully open for cooling the horizontal damper, which can be seen through the bodywork.

The spring made contact with the left-hand side of Massa's helmet, above the visor between his forehead and temple. His latest-spec Schuberth RF1 helmet stood up well, taking the impact near the visor opening where it could flex under a force of over 60 newtons. It was this impact and compression that caused the injury to Massa's skull and left eye.

The car slowed to 62mph before it struck the wall. Although Massa's feet were on the pedals, they were not exerting any real pressure - the loss of speed was mainly due to the car's natural drag over a long distance. Despite the violence of the secondary impact, with the barrier, it is unlikely to have led to any significant injury.

It would be foolish to purely dismiss it as a freak accident; lessons can always be learned. Parts falling off cars is inevitable, though a rear damper failure is a rare occurrence. Enclosing the rear mechanical parts would be an option, either by fully surrounding the area with bodywork or by suitably strong mesh.

Helmet safety has improved from an already high standard, but they also have to be lightweight - not for performance reasons but for safety. A driver already needs a strong neck to hold up a helmeted head in a 5g corner, so anything heavier than the current 1200g would be near impossible to wear over a race distance. The FIA has suggested that action will be taken to influence helmet development and testing.

The media has mooted cockpit canopies as a potential solution - either fully enclosed or open-topped. But the canopy goes against the view of what a single-seater should look like, as well as raising escape and visibility issues.

Brawn

A new rear beam wing and diffuser (yellow) created more rear downforce. © AUTOSPORT

Despite suffering from increasing problems with rear tyre temperature, Brawn has been developing the car over the past races and has introduced a revised front wing, rear wing and diffuser. The latter should have aided rear downforce, but has not eased the tyre problems.

Developments for recent races included a totally new rear beam wing, which is no longer merged into the rear crash structure but instead sits proud presenting more surface area to the airflow. Beneath this, the upper deck of the diffuser has been raised with a section sitting well above the driveshaft, adding a large amount of the extra volume. At the front, a large front wing flap has added more downforce, combined with an under-wing fence to keep the low pressure area segregated under the wing.

The rear-tyre graining is a very similar problem to that faced by teams in recent years with graining on the old, front grooved tyres. If the tyre doesn't come up to the right operating temperature, it doesn't grip and as a result slides over the track surface. This pulls rubber off the tyre's surface and forms balls which further reduce grip.

Low tyre temperature cannot by solved by simply warming the tyres up in heater jackets, as it will soon drop once on track. Tyre temperature is dependent on several factors; downforce, weight distribution, suspension geometry and compliance, while the track has its own factors such as ambient temperature, number of fast turns and surface texture.

Brawn has plenty of downforce and weight distribution which can be reapportioned rearwards, but the problem is likely to be in the suspension geometry. Teams have the choice to be easy or hard on tyres, the trade off being between high tyre wear on aggressive tracks or low tyre temperature on easier ones. Altering suspension geometry is difficult to do quickly, and not something teams tend to change for each track.

However, damping can be tuned. The way the suspension damps the tyre's motion can alter the amount of sidewall deflection, which in turn can create heat in the tyre. This can be with either the individual wheel dampers or the inerter damper. By altering the high-speed wheel dampers, the tyre's sidewall can be worked to alter the heat it generates. While similar tuning of the Inerter damper can be used, normally the inerter is used to cancel out tyre movement and a secondary outcome of this is reducing the heat generated. But equally, altering the tuning of the Inerter can create sidewall movement and heat in the tyre. It seems with testing banned, Brawn lacks the track time to try out different set-ups.

Many in the media have cited track temperature as the key to Brawn's problems, which is quite true in some respects. Friday's practice was warmer and the rear tyre wear was under control, but relatively cooler temperatures on the other days brought the problems back. But both Germany and Hungary are slow tracks, there are no fast turns to put load into the tyres and generate heat. This and the temperature is what caused the team's performance problems. Silverstone had fast turns but was very cold.

The upcoming races do not bode well for Brawn, with slow tracks at Valencia and Singapore, and unpredictable weather in Europe. Japan and Brazil could decide the outcome of the championship.

BMW Sauber

BMW followed other teams lead with slots in its otherwise unique endplate © AUTOSPORT

Ahead of a major update due for the Singapore GP, BMW pressed ahead with smaller updates to the F1.09 for Hungary. There was the introduction of another front wing endplate. Retaining the usual boxy outline, the new endplate sports two slots in its vertical face, one full height and one smaller duct ahead of it. These slots vent higher pressure from outside the plate and send it along the inside face to help route the airflow around the front wheel.

Despite following the fashion for vents, the general format of BMW's endplate does not follow the trend towards smaller upright sections, and no other team sports the upper horizontal element. It seems BMW is alone in following its format of endplate design since its 2009 interim car tested last year.

However, BMW did try a dummy raised monocoque in what would have been preparation for the 2010 season. But now that the team has withdrawn from next year's championship, we might not get to see the BMW iteration of what is rapidly becoming next season's must have design. Curiously, BMW's dummy nose section featured the same rounded edges as used on the nose cone.

Red Bull Technologies

New front wheel fairings were tried on Friday © AUTOSPORT

With the recent upgrades making the RB5 the class of the field, updates to the Red Bull Racing (RBR) cars were limited for Hungary, while Toro Rosso finally adopted the same configuration fitted to RBR at Silverstone.

For RBR, the main development was the testing of McLaren-style extended wheel fairings. These were tested briefly on Friday and were not raced.

Unlike McLaren's sleek fairings, Red Bull's versions were very wide, sporting a gurney flap around most of the perimeter to create a dish-like shape. These fairings pick up the flow from the front wing endplate and smooth its paths towards the rear of the car. The Red Bull-shaped fairings probably take a more aggressive route to achieve this.

Toyota

Extra rear downforce was added to the Toyota with these two winglets © AUTOSPORT

It seems that Toyota has an efficient and stable car from an aerodynamic point of view, but it still lacks absolute downforce. In order to increase the car's total downforce at the expense of drag, the team fitted two extra rear wing elements in Hungary.

Firstly, a BMW-like single element winglet above the rear wing, and a strut-mounted double element rear wing below it. Both these winglets would have added downforce in their own right, but also aided the airflow over the rear wing, preventing it stalling at the steep angle of attack required for creating downforce at the Hungaroring.

Super slow motion footage from the German GP showed the front wing endplate elements flexing in an alarming manner over the kerbs. Toyota mounted an R-shaped winglet to the footplate of the front wing, which was wobbling, hitting the main upright part of the endplate and flexing the footplate in the process. It's clear that this is not performance enhancing flex, probably quite the opposite as the rapidly changing geometry of the front wing would make the aerodynamics more inconsistent. For Hungary, Toyota added a small stay to fix the winglet to endplate to prevent the flexing.

Williams

A simple slot gave Williams more scope for a steeper rear wing in Hungary © AUTOSPORT

Following encouraging performances in recent races, Williams brought several small updates to the front wing and rear wing to Hungary. The front wing was a subtly revised version of the German GP wing and endplate.

The most visual change was a small vane added to the endplate sitting behind the larger Brawn-like vane on the footplate.

At the rear, the steeper high downforce wing ran a small 15cm slot to prevent the airflow passing under the wing from stalling.