The 2006 Technical Review (part II)

Although spotlight in the world championship battle was on the differing tyre performance of the top two teams by the end of the season, there was an intriguing undercurrent of aerodynamic and chassis development among the entire field and throughout the year.

Aided by a stable set of chassis rules, the teams pressed the definition of the technical regulations harder than at any point in recent years. In fact, not since the ban on active driver aids has the technical aspect of the sport created so many headlines.

Aerodynamics

After a raft of changes in 2005 to front wing heights, rear wing placement, and diffuser design, no real aerodynamic rule changes were made for 2006.

As the year progressed, teams converged on similar solutions. By and large these solutions were aimed at reducing drag and not creating downforce per se. As the cars had less power this year, they no longer had the surplus to carry large wings to improve lap times. Thus, the cars had to be more efficient at creating downforce.

This was especially the case at the rear of the car, where the smaller diffuser contributed less than the draggy rear wing. Teams opted to take the flow off the front wing and direct it more effectively to the rear wing and diffuser. This moved the centre of pressure (the balance of downforce front to rear) backwards.

Most teams adapted their monocoques to better locate the front wishbones in respect of the front wing. This lead to a degree of convergence on keel design. Most teams had previously settled on the lighter/stiffer single keel design for 2005, but this year many followed McLaren's path on the so-called "zero keel", which mounts the lower wishbone higher up and directly on to the chassis.

It is the placement of the wishbone that is most influential in this design, as the wishbone's profile works better with the front wing, actively improving the aerodynamics around the front of the car. This is not as easy to achieve with the lower mounting on a single or V keel (as used by Ferrari and Renault).

Despite the major structural, suspension, and aerodynamic changes for the keel-less design, the result was not decisive in pace, and only Jenson Button's win in Hungary was with a Keel-less car.

Increasingly seen as a major contributor to the overall aero design were the bargeboards.

Bargeboards have several influences nowadays. Their first function is to manage the pressure distribution under the floor, making sure the diffuser is evenly fed with high pressure air. Secondly, the boards turn the flow off the front wing around the sidepods to the lower rear wing and over the diffuser.

There seems to be two philosophies: those with larger boards towards the rear, and those with most of the elements around the front suspension. Such is the complexity of these devices that it's now hard to classify which team have which philosophy.

Notably, Ferrari, Renault and McLaren tend to favour the larger rear boards. However, all these teams also run an array of vanes mounted ahead of the larger boards.

Detail design has also converged here: all teams are running "axe head" type fins at floor level, ahead of the rear mounted boards. The foot plate along the bottom of the main board is also now saw-toothed, with several teams adding a curled lip to the leading edge of these sharp edges.

Following on from the bargeboards are the undercut sidepods now mated with shoulder wings or fins on most teams. These are relatively new devices to be adopted across the grid, despite being on the Jordans and Toyotas for several years.

The large endplate collects the flow passing off the front wing that passes around the inside of the wheel; it stops the flow stagnating, and it speeds it up around to the rear of the car, while the winglet joining the endplate to the sidepod creates a vortex that also speeds up the flow passing around the chimney and winglet.

All these flows improve downforce create at the rear, to the slight detriment of front downforce.

Technical Controversies

Tower Wings

BMW created a stir with their mid-season bodywork upgrade. The so-called tower wings fitted ahead of the cockpit were controversial as they impinged the driver's field of view and also looked unsightly. Their purpose was never fully revealed, but their somewhat diverging angle to the airflow no doubt directs the flow around the cockpit and roll structure more efficiently.

A better clue came from Red Bull's technical director Adrian Newey, who suggested that the devices work mainly when the car is in yaw (at an angle to the direction of travel). When the car is in yaw, the inner fin is straighter and has little effect, but the outer fin will produce a vortex that speeds up the flow around the outside of the car. This replaces the flow to the rear wing that would otherwise be shielded by the roll structure.

This is similar to the function of the Viking wings fitted to Newey's McLarens and also adopted by BMW-Sauber at the same time as the tower wings. It's generally accepted that F1 cars are not gaining much in terms of efficiency in a straight-line running and that the improvements are now being sought at different attitudes to the track - such as yaw, pitch and roll.

Flexing wings

At the start of the year, several teams and then the media picked up on the flexing wings debate. The design of both the Ferrari and BMW-Sauber wings were called into question. This is not a new argument and no team ever actually failed the FIA deflection test, which is the only measure of wings' legality in F1.

It was believed that the rear flap of the cars was flexing at speed, reducing drag and improving the car's pace. This situation was only noticed when on-board TV footage showed Ferrari's front wing to flex, with the sliding mounting for the bi-plane element being exposed at speed.

Every team has to account for the increasing load the wings experience with speed, and the FIA mandates a maximum deflection for a given load, at several points along the wing. Above this load, the deflection is not measured and considered legal. Many teams are believed to take advantage of this situation and allow the wings to flex controllably at higher loadings to produce a reduction in drag.

To tame the situation, the FIA requested several teams to alter their wings, and the governing body introduced a slot gap separator to prevent the gap between the wings from altering at speed and hence creating the drag reduction.

Wheel fairings

At the first race, Ferrari appeared with small carbon fibre fairing attached to their rear wheels. The common belief was that the rims improved the car's aerodynamics by covering the open rear wheel face and thus reducing drag.

This conflicted with two established rules on movable aerodynamic devices and wheel construction.

Regardless, these went largely unchallenged until larger versions were introduced almost enclosing the rear wheel race. Yet still no protests were raised or any argument arose from the FIA.

Ferrari's case - and by that time Toyota's too, as they began using a similar device - was that these fairings formed part of the brake duct. Indeed, the brake duct was an aerodynamic area that was freed up under the rules for 2006, which also led to the winglets added to the inner brake ducts by several teams.

The brake cooling case for Ferrari is upheld as the cooling flow (blue) from the discs passes back out the inside of the rear wheel (red). The fairing (yellow) prevents the flow passing out through the outer face. Therefore, improvement in overall drag was merely a coincidental by-product. Toyota meanwhile route their flow through the outside face of the wheel, watering down their case somewhat.

The case that the fairing broke the single material wheel rules was again defended by the parts being part of the brake ducts and not the wheel. In both cases the fairings were attached with bolts to the wheel and could not be considered structural.

Ferrari's more enclosed design did create problems for rapid and reliable pitstops, thus the enclosed versions were fitted for the first stint and the more open design was used for the race pitstops.

Mass Dampers

While the other technical controversies created a stir, few probably have had any impact on a team's competitiveness. The ban on mass dampers, however, seemed more crucial.

The debate over mass dampers started quietly and soon erupted into a major controversy. First adopted by Renault last year, the "tuned mass damper" is basically an aid to overcome the imbalance between the stiffly sprung F1 car and its bulbous bouncy tyres.

In most cars, the suspension travel accounts for almost 90% of the springing, with the tyre producing a smaller input. In an F1 car, the situation is quite the opposite, with most of the springing coming from the tyre. Unlike the suspension, the tyre is an un-tunable spring, and the teams can do little to alter its rate or damping. This leaves the otherwise well prepared F1 engineer with a large uncontrollable factor in setting up the car.

Renault took a basic device used in some softly sprung road cars to provide a degree of tunable control. By placing a weight between two springs, the weight can be tuned to reverse the natural oscillation of the tyre. The benefit is that the team can ensure the tyre is consistently loaded throughout the lap, regardless of bumps and weight-shift from manoeuvring. If the tyre is ideally loaded at all time, more of its potential performance can be used, giving obvious improvements in pace and consistency.

Many other teams adopted this design - according to the FIA, as many as seven of the eleven teams ran the device in 2006 - but Renault had the upper hand and had designed the 2006 suspension and gearbox (to accommodate a rear mass damper) to maximise its use.

By Monaco the secret was out, but it took the FIA until after the French GP to act and ban the devices. The governing body did so under the auspice of the movable aerodynamic rules, suggesting that the device controlled ride height and as such aided aerodynamics. The FIA could have easily used the ballast regulations, and Toyota cited this rule as their own reason not to adopt the device.

In any event, the eventual ban was just ahead of the August testing break, which left Renault compromised in how much track testing they could do to retune their suspension geometry to work without the tuned mass damper.

Teams' Developments

Ferrari

After their disappointing 2005 season, the outwardly little changed car appeared late in testing to replace the two years old F2004M interim car. Early season pace was there, but the car struggled in qualifying and came on stronger in the races. Then, Bridgestone altered their tyres mid season and Ferrari started a run of suspension and aero upgrades that significantly improved the team's pace.

Their pace then eclipsed that of Renault, taking wins on merit and with qualifying pace to match that in the race. In fact, the tyres seemed to have reversed into good one-lap pace with more questionable durability in the race.

Flexing wing issues were much talked about early in the season, but although the flex was evident, it was never clear or proven whether this was intentional or illegal. Later, the adoption of mass dampers was proven and then the wheel fairing that started out as a simple rim cover soon expanded to almost enclosed covers. Again, the rules had been worked out and the response proved Ferrari's interpretation to be legal (even if somewhat outside the spirit of the regulations).

In other areas of aerodynamics, Ferrari shared the lead with Renault in innovation, running an aggressive multi-plane diffuser, matched to a lower beam wing split over the diffuser.

Feeding the diffuser were the most complex bargeboards to date. Ferrari use larger boards with a stepped footplate, and the steps in the footplate are also curled up. More detail work on the axe-heads led to a small turning vane that was added to the fin late in the season.

Race reliability remained solid with only one, albeit important, engine related retirement in Japan. But there were also quite a few precautionary engine changes, suggesting the pace of development had hit Ferrari's usual rock solid reliability.

Ferrari also continued to run a conventional gear selection system, within the carbon reinforced case. The team have been developing two paths, one more complex and a simpler version. They plan to head down the latter route, which is supposed to be lighter and more reliable, for introduction next year.

Honda

After dropping in competitiveness in 2005, a lot was expected from the now fully Honda owned team. The car was derived from the BAR006 and 007, but the bulky sidepod and cooling layout was refined into a more conventional undercut sidepod and chimney design, allied to much more radical shoulder fins.

However, the car did not work well with its Michelin tyres, the drivers often reporting no grip from the car on qualifying runs or during stints in the race. This inconsistency was exacerbated when a safety car was called out, the Honda drivers needing to weave the car to warm the tyres even on the first lap after the safety car was called in. The inability to run enough downforce was cited as one of the reasons for the problem.

Honda also seemed to be lost with their aerodynamic development leading up to mid season, with differing bargeboard and rear wing layouts adopted and discarded.

The departure of technical director Geoff Willis around that time probably did little to stabilise the team, as well as the loss of Willem Toet, who was commissioning the second wind tunnel. By the middle of the season things were improving, though, and while the first win in the damp in Hungary was probably not directly attributable to the car's development, thereafter the team performed strongly in conjunction with the tyres.

Honda's all-new V8 engine was among the best on the grid for power, but reliability and drivability were suspect. Seven race retirements due engine failures were also mated with several pre-race engine changes - albeit two of these because of the hurriedly introduced 2007-spec engine, which blew up in the back of Anthony Davidson's car in practice for the Italian Grand Prix.

BMW-Sauber

It was quite an achievement for the newly merged BMW-Sauber team to arrive in Bahrain with a substantially new car. BMW needed to both develop their new engine and inject resources into the Sauber team. For this season, Sauber developed both the chassis, electronics and transmission, but the latter pair will come under BMW Motorsport's drivetrain programme as of next year.

The 2006 chassis sported a new low-line monocoque, featuring a keel-less suspension design. The aerodynamics continued the extreme sculpting of the sidepods seen on the Sauber car in 2005, allied to a new front wing and tall engine cover.

The engine cover was one of the first areas to be updated with revised winglets, cooling outlets, and the spine was heightened with a removable panel. Then, BMW-Sauber really set the cat among the pigeons with their tower wings, introduced in testing and raced in France.

These and other aero solutions typified the new aggressive aero development taken up by the Hinwil-based team all year. Meanwhile, the BMW V8 engine quietly progressed, although it is probably not the top engine in the field. Its reliability was fair, with three race failures - although two of them were very early in the year.

Red Bull-Ferrari

With the team's announcement of a Ferrari engine supply in 2006 announced as early as Monaco last year, and with the recruitment of Adrian Newey and Mark Smith a year ago, Red Bull Racing approached the new season well in advance, and the new car ran already at the start of January.

The car was overseen by ex-Renault designer Mark Smith, and his Renault influence was visible in the sidepod shape, V-keel, and reinforcing struts over the engine. With Red Bull (nee Jaguar) having run a very conservative car for several years, the RBR3 was a major development step for the team.

However, a mismatch between the Ferrari engine's cooling requirements and its installation in the Red Bull chassis wrecked these early tests. A hurriedly revised radiator and sidepod shape were introduced to resolve the issue, but both time and performance were lost in the process.

Thereafter, the team made little visible progress - a further refinement to the cooling was made, along with some alteration to the fins over the nose. By mid-season, all efforts were focused on the all-new car for 2007, which latterly has been announced as running the Renault engine, further reinforcing the experience Mark Smith brings to the team.

As an impact of the team's departure from previous Red Bull designs, the usual reliability that had served the team so well in 2005 was lost. The main bugbear was the hydraulics and gearbox, which forced eight race retirements, while the Ferrari engine remained reliable for every round.

Spyker MF1-Toyota

With the team carrying over the Toyota engine supply from their reliable 2005 season, Midland were at last able to make a big step on their chassis. Even if some of the designs were Jordanesque, the car was substantially new.

The monocoque, suspension aerodynamics and gear casing were all revised. Sporting a fashionable keel-less front-end, tightly sculpted sidepods, and a rear suspension operating rotary dampers, the car looked a match for the rest of the grid.

While no doubt the car was progress, it did not jump the team up the grid, and again development throughout the year was slow. Development highlights were the new front and rear wings for Turkey.

Engine reliability was maintained, but the car did suffer from mechanical failures, including driveshaft failures - one of which lead to Christijan Albers's dramatic suspension failure in Japan.

Super Aguri-Honda

Rushed to the grid in a matter of just three months, Super Aguri took over the aged Arrows chassis and factory. Then, with the help of Honda R&D in Japan, the new team brought a car to race in Bahrain.

The basis of the SA05 car was the Arrows A23 monocoque and carbon fibre gearbox. These all needed mating to the new Honda V8 Engine, via revised engine mounts and spacer plate twixt engine gearbox. Aerodynamic updates were quickly established, based as much on eye and experience as with CFD or wind tunnel work.

The new car both qualified ahead of other cars and achieved race finishes in its early races, but then gearbox/hydraulic problems slowed the team's results mid season.

The team brought new parts to every race - their rate of development was clearly backed by resources to design and make new parts. Then, the team produced the SA06, which was the definitive 2006 car, and while it rolled out later than the original Imola date, the revisions were far reaching.

The whole rear end was updated, with a Honda-developed seamless shift gearbox and rear suspension. Up front, the distinctive keel fairing were discarded for simpler bargeboards, and for Turkey the twin keel insert was shortened to prove a near keel-less front end.

With this pace of development, reliability suffered, but for the last race, in Takuma Sato's hands, the car was a match for the pace of most of the rear-grid teams.

We want to hear from you!

Let us know what you would like to see from us in the future.

Take our survey

- The Autosport.com Team

Read and post comments