Whenever an F1 car runs on track, the team will have planned what parts are fitted and the set up of every facet of the car. Now over a year and a half old and with an even older car, this set up sheet appeared on the Lotus Media site. It was from Kimi Raikkonen’s debut test at Jerez for the team in a R30 (from 2011). It shows some of the set up detail that the teams go into. This also gives us some insight into the spring\damper configuration modern F1 cars run.
Not everything in F1 is aggressive, extreme, radical or innovative. In fact in many areas the car’s are very close in general design terms. Some time it’s enough just to soak up the detail engineering and explain what all the little bits and pieces do on the car. In this series of short articles, we’ll do just that, thanks to these amazing photographs from MichaelD.
This is the front left corner of the VJM05, seen without the wheel to expose the brakes, suspension mounts, hub and electronics. Details vary from team to team, but what we see here is typical of most F1 cars, indeed some of the components are standard (electronics) or lightly modified by the supplier (brakes).
Dominating the picture is the brake caliper. This is supplied by AP Racing and will be designed around Force India requirements, albeit based on their current iteration of an F1 Caliper.
F1 Bake calipers must have no more than six pistons, two pads and two mounting points. The material is restricted by an 80Gpa stiffness requirement; aluminum lithium is most commonly used.
AP have a unique design of caliper for many Formulii, with their RadiCal (Radical Caliper) design. This being the way the inner and outer sections join via the complex bridge structure, to make it as stiff as possible. We can see the caliper is bridged in two places and a radial brace is also used. Keeping his area open is important for cooling the brake disc.
Cooling is also behind the structure around the pistons, the cylinders the six pistons within are nearly completely exposed, with just some links to the calipers structure and internal passageway to route the brake fluid. This allows the most airflow around the cylinderpiston to keep them cool. The pistons themselves are made in titanium and have a series of radial holes machined into them to also keep heat from getting into the brake fluid.
We can see the brake line entering the caliper at the bottom, having been routed through the lower wishbone. At the top of the caliper are the two bleed nipples, these allow bubbles trapped within the system to float up and be removed for better brake feel.
The carbon panel on the outer section of the caliper is either an aero piece or some protection for the caliper when the wheels are slammed back on during pitstops.
Discs and Pads
F1 moved to Carbon discs and pads in the eighties, having moved straight from Cast iron discs. Strangely ceramic discs have not been a development seen at races. Rules limit the diameter and thickness of discs, but no other regulatory restrictions are placed on these parts.
Disc and pad material varies according to their manufacturer (Carbon Industrie & Hitco). It is also tuned for each race and even for each driver. Additionally cooling patterns will vary from track to track, For Force India in Melbourne we can see the high density drillings, with three small drillings across the disc. With Melbourne being heavy on braking the pads are also drilled in attempt to keep the brake system cool. Brakes and pads wear at an equal rate, so the few millimeters gap in between disc surface and drillings is all the wear these parts will see, before catastrophic failure. As wear increases with temperature there are sensors measuring the disc surface temperature and also wear sensors for both the inner and outer pads.
To monitor all the functions on the front corner, there will be an array of sensors fitted to the parts. These are all linked back to the main SECU, rather than cabling for each sensor passing through the wishbones to the cars main wiring loom, there is a hub fitted to the upright that collects all he signals and passes them back via a single cable. This Hub Interface Unit (HIU) is a common part supplied by MES to all the teams. It has inputs from the aforementioned Pad wear and disc temperatures sensors, as well as two wheel speed sensor (two in case one fails), also a load cell for measuring pushrod (or pullrod) loads.
Although the aluminum upright can barely be seen beneath the brake ducts, the key function of the upright is joins the hub to the suspension. F1 does not use adjustable suspension in the same way as many racecars. That is with threaded adjusters, but instead solid suspension links are mounted the hard points with shims. These shims are used to alter the camber, ride height, pushrod offset and castor.
Teams are no longer aligning the track rod for steering with the FTWB. So often the track rod needs a separate lower mounting point on the upright. When adjusting camber, a different FTWB shim will alter the steering toe angle, so an additional shim needs to be fitted to the track rod clevis t maintain toe angle.
In this picture, we can see the upper clevis that mounts the front top wishbone (FTWB) and track rod. Force India have done this with the VJM05, but have still been able to join the FTWB and track rod to the same clevis assembly. This way camber can be adjusted with a single shim, rather than separate but matched shims for separate clevises.
We can also see the extremely high front lower wishbone position (FLWB); it’s nearly at the front axle height. Having wishbones spaced further apart is better for reducing the loads fed through them, but aerodynamics demand a higher position. We can’t see the outboard joint with the upright; neither can we see the outer pushrod joint. It’s probably that FIF1 mount these mount to the upright in a set up called ‘pushrod on upright’ (POU), this helps eight transfer with steering angle in slow corners.
For 2012 we will have a raft of rules changes that will alter the look and performance of the car. For most of the new cars, we will immediately see the impact of the lower nose regulations. Then the big story of 2010-2011 of exhaust blown diffusers (EBDs) comes to an end with stringent exhaust placement rules and a further restriction on blown engine mappings.
Even without rule changes the pace of development marches on, as teams converge of a similar set of ideas to get the most from the car. This year, Rake, Front wings and clever suspensions will be the emerging trends. Sidepods will also be a big differentiator, as teams move the sidepod around to gain the best airflow to the rear of the car. There will also be the adoption of new structural solutions aimed to save weight and improve aero.
Last of all there might be the unexpected technical development, the ‘silver bullet’, the one idea we didn’t see coming. We’ve had the double diffuser and F-Duct in recent years, while exhaust blown diffusers have thrown up some new development directions. What idea it will be this year, is hard, if not impossible to predict. If not something completely new, then most likely an aggressive variation of the exhaust, sidepod or suspension ideas discussed below.
The most obvious rule change for 2012 is the lowering of the front of the nose cone. In recent years teams have tried to raise the entire front of the car in order to drive more airflow over the vanes and bargeboards below the nose. The cross section of the front bulkhead is defined by the FIA (275mm high & 300mm wide), but teams have exploited the radiuses that are allowed to be applied to the chassis edges, in order to make the entire cross section smaller. Both of these aims are obviously to drive better aero performance, despite the higher centre of Gravity (CofG) being a small a handicap, the better aero overcomes this to improve lap times.
A safety issue around these higher noses is that they were becoming higher than the mandatory head protection around the cockpit, in some areas this is as low as 55cm. It was possible that a high nose tip could easily pass over this area and strike the driver.
So now the area ahead of the front bulkhead must be lower than 55cm. However the monocoque behind this area can remain as high as 62.5cm. Thus in order to strive to retain the aero gains teams will keep a high chassis and then have the nose cone flattened up against this 55cm maximum height. Thus we will see these platypus noses, wide and flat in order to keep the area beneath deformable structure clear for better airflow. The radiussed chassis sides are still allowed so we will also see this 7.5cm step merged into the humps a top of the chassis.
Areas below and behind the nose are not allowed to have bodywork (shown yellow in the diagram), so small but aggressive vanes will have to be used, or a McLaren style snowplough. Both these devices drive airflow towards the leading edge of the underfloor for better diffuser performance.
Having used the engine via the exhausts to drive aerodynamic performance for the past two years, exhaust blown diffusers will be effectively banned in 2012. The exhausts must now sit in small allowable area, too high and far forward to direct the exhausts towards the diffuser. The exhausts must feature just two exits and no other openings in or out are allowed. The final 10cm of the exhaust must point rearwards and slightly up (between 10-30 degrees). Allied to the exhaust position, the system of using the engine to continue driving exhaust when the driver is off the throttle pedal has also been outlawed. Last year teams kept the engine throttles opened even when the driver lifted off the throttle for a corner. Then either allowing air to pass through the engine (cold blowing) or igniting some fuel along the way (hot blowing). The exhaust flow would remain a large proportion of the flow used when on the throttle, thus the engine was driving the aero, even when the driver wasn’t needing engine power. Now the throttle pedal position must map more closely the actual engine throttle position, thus if the driver is off the throttle pedal, then the engine throttles must be correspondingly closed.
Teams will be faced with the obvious choice of blowing the exhausts upwards towards the rear wing, to gain a small aerodynamic advantage, when the driver is on the throttle. These Blown Rear Wings (BRWs) will be the conservative solution and certainly will be the first solution used in testing.
However, it’s possible to be aggressive with these exhaust designs too. One idea is blowing the rear wing with a much higher exhaust outlet; this would blow tangentially athte wing profile, which is more effective at increasing the flow under the wing for more downforce. Packaging these high exhausts may cause more problems than gains. But last year’s exhausts passing low and wide across the floor suffered a similar issue, but proved to be the optimum solution.
Even more aggressive solution would be directing the exhausts onto the vanes allowed around the rear brake ducts. If avoiding the brake cooling inlet snorkel, the fast moving exhaust gas would produce downforce directly at the wheel, which is more efficient than wings mounted to the sprung part of the chassis. However the issue here would be the solution is likely to be so effective, that it will be sensitive to throttle position and rear ride height. If these issues can be engineered out, then this is an attractive solution.
Wing ride height and Rake
With rules setting a high front wing ride height and small diffusers, aero performance is limited. So teams have worked out how to work around these rules by angling the entire car into a nose down attitude. This is known as ‘Rake’, teams will run several degrees of rake to get the front wing lower and increase the effective height of the diffuser exit. Thus the front wing will sit closer to the track, than the 75mm when the car is parallel to the ground. While at the rear, the 12.5cm tall diffuser sits an additional 10cm clear of the track, making its expansion ratio greater. Teams were using the EBD, to seal this larger gap between the diffuser and the floor. Without the EBD teams will have to find alternative way to drive airflow into the gap to create a virtual skirt between the diffuser and track.
Furthermore teams have also allowed the front wing to flex downwards at speed to allow it to get closer to the ground, further improving its performance. Although meeting the FIA deflection tests, teams are allowing the wing bend and twist to position the endplate into a better orientation, either for sealing the wing to the ground or directing airflow towards the front tyres wake. Both creating downforce benefits at the front or rear of the car, respectively.
One issue with allowing the wing to ride closer to the ground through rake or flexing, is that at high speed or under braking (when the nose of the car dives), the front wing can be touching the ground. This is bad for both aero and for creating sparks, which will alert the authorities that the wing is not its normal position relative to the chassis. So teams are creating ways to manage front ride height. Traditionally front bump rubbers or heave springs will prevent excessively low ride heights. Also the front suspension geometry runs a degree of geometric anti-dive, to prevent the nose diving under braking.
Last year we saw two additional solutions, interlinked suspension, where hydraulic suspension elements prevent nose dive under braking by displacing fluid in a hydraulic circuit one end of the car to the other end, creating a stiffer front suspension set up. This prevents dive under braking, while keeping a normally soft suspension for better grip.
We have also seen Lotus (nee LRGP) use torque reaction from the front brake callipers to extend the pushrod under braking, creating an anti-dive effect and prevent the nose dipping under braking.
These and probably other solutions will be seen in 2012 to maintain the ideal ride height under all conditions.
Towards the end of last year, front end aero design was converging into a set of similar ideas. Aside from the flexible wing option, already discussed above. The main direction was the use of a delta shaped threefour element wing, sporting no obvious endplate. The delta shape means that most of the wings downforce is created at the wing tip; this means less energy is taken from the airflow towards the inner span of the wing, which improves airflow at the rear of the car. Also the higher loading near the wing tip creates a stronger vortex, which drives airflow around the front tyre to reduce drag. Three wing elements are used, each being similar in chord length, rather than one large main plane and much smaller flaps. This spaces the slots between the elements out more equally, helping reduce airflow separation under the wing. More slots mean a more aggressive wing angle can be used without stalling. At the steepest outer section of wing, teams will mould a fourth slot in the flap to further manage airflow separation.
First introduced by Brawn in 2009, the endplate-less design is used as it’s more important to drive airflow out wide around the front tyre, than to purely maintain pressure difference above and below the wing. Rules demand a minimum amount of bodywork in this area, so vanes are used to both divert the airflow and meet the surface area regulations. This philosophy has now morphed into the concept, where the wing elements curl down to form the lower part of the endplate. Making the wing a homogenous 3D design, rather than flat wing elements and a separate vertical endplate.
A feature starting to emerge last year was arched sections of wing. Particularly near the mandatory neutral centre 50cm section of wing. These arched sections created elongated vortices, which are stronger and more focussed than tip vortices often used to control airflow. In 2012 many teams will create these unusual curved sections at the wings interface with the centre section.
Above this area, the pylon that mounts to the wing to the nosecone has been exploited to stretch he FIA maximum cross section to form the longest possible pylon. This forms the mounting pylon into endplates either side of the centre section of wing and along with the arched inner wing sections, help create the ideal airflow 25cm from the cars centreline (known as the Y250 axis).
In 2011 Mercedes GP used a section of the frotn wing to link up with the fins on the brake ducts, this created an extra long section of wing. Vanes on the front brake ducts are increasingly influential on front wing performance and front tyre wake.
Mercedes GP also tried an innovative F-Duct front wing last year. This was not driver controlled, but rather speed (pressure) sensitive. Stalling the wing above 250kph, this allowed the flexing wing to unload and flex back upwards at speed, to prevent the wing grounding at speed. But the effect altered the cars balance at high speed, and the drivers reportedly didn’t like the effect on the handling. I’ve heard suggestions that the solution isn’t planned for 2012.
With so much of the car fixed within the regulation, it’s becoming the sidepods that are the main area of freedom for the designers. Last year we saw four main sidepod concepts; Conventional, Red Bull lowtapered, McLaren “U” shape and Toro Rosso’s undercut.
Each design has its own merits, depending on what the designer wants to do with the sidepods volume to get the air where they want it to flow.
This year I believe teams will want to direct as much airflow to the diffuser as possible, Red Bulls tiny sidepod works well in this regard, as does the more compromised Toro Rosso set up. Mclarens “U” pod concept might be compromised with the new exhaust rules and the desire to use a tail funnel cooling exit. However the concept could be retained with either; less of top channel or perhaps a far more aggressive interpretation creating more of an undercut.
Part and parcel of sidepod design is where the designer wants the cooling air to enter and exit the sidepod. To create a narrower tail to the sidepod and to have a continuous line of bodywork from sidepod to the gearbox, the cooling exit is placed above the sidepod, in a funnel formed in the upper part of the engine cover. Most teams have augmented this cooling outlet with small outlets aside the cockpit opening or at the very front of the sidepod.
To let more air into the sidepod, without having to create overly large inlets, teams will commonly use inlets in the roll hoop to feed gearbox or KERS coolers.
Even without the exhaust blowing over the diffuser, its design will be critical in 2012.
As already mentioned the loss of the exhaust blowing will hurt the team’s ability to run high rear ride heights and thus a lot of rake. Unobstructed the EBDs exhaust plume, airflow will want to pass from the high pressure above the floor to the lower pressure beneath it. Equally the airflow blown sideways by the rear tyres (known as tyre squirt) will also interfere with the diffuser flow.
Before EBDs teams used a coved section of floor to pickup and accelerate some airflow from above the floor into the critical area between the diffuser and rear tyre. I predict we will see these shapes and similar devices to be used to keep the diffuser sealed at the sides.
Last year we saw teams aid the diffusers use of pulling air from beneath the car, by adding large flap around its trailing edge. So a high rear impact structure raised clear of the diffusers trailing edge will help teams fit these flaps around its entire periphery. Red Bull came up with a novel ideal by creating a duct feeding airflow to the starter motor hole; this improves airflow in the difficult centre section of the diffuser. Many teams will have this starter motor hole exposed by the raised crash structure, allowing airflow to naturally pass into the hole. However I expect some vanes or ducts to aid the flow in reaching this hole tucked down at the back of the car.
DRS was a new technology last year. We soon saw teams start to converge on a short chord flap and a high mounted hydraulic actuator pod. DRS allows the rear wing flap to open a gap of upto 50mm from the main plane below it. A smaller flap flattens out more completely with this 50mm gap, reducing drag more effectively than a larger flap.
As drag is created largely at the wing tips, I would not be surprised to see tapered flaps that flatten out at the wing tip and retain some downforce in the centre section. Teams may use the Pod for housing the actuators, although Mercedes succeeded with actuators hidden in the endplates. Having the pod above the wing clears the harder working lower surface, thus we will probably not see many support struts obstructing the wing.
Super slim gearboxes have been in vogue for many years, Last year Williams upped the stakes with a super low gearbox. The normally empty structure above the gear cluster was removed and the rear suspension mounted to the rear wing pillar. Williams have this design again for 2012, albeit made somewhat lighter. With the mandatory rear biased weight distribution the weight penalty for this design is not a compromise, while the improved air flow the wing is especially useful in 2012. So it’s likely the new cars will follow the low gearbox and low differential mounting in some form.
A lot is said about Pull rod rear suspension being critical for success. In 2011 only a few teams retained push rod rear suspension (Ferrari and Marussia). I would say the benefits between the two systems are small; pushrod trades a higher CofG for more space and access to the increasingly complex spring and damper hardware. Whereas pull rod benefits from a more aerodynamically compact set up and a lower CofG. I still believe either system works well, if packaged correctly.
At the front it’s unlikely pull rod will be adopted. Largely because the high chassis would place a pull rod at too shallow an angle to work efficiently. Regardless the minimum cross section of the footwell area, discounts any potential aero benefits. Leaving just a small CofG benefit as a driver to adopt this format.
Most teams now use a metal structure to provide strength inside the roll hoop; this allows teams to undercut the roll hoop for better airflow to the rear wing. Even though last year two teams followed Mercedes 2009 blade type roll hoop, for Caterham at least, this isn’t expected to return this year. Leaving the question if Force India will retain this design?
Electronics and control systems
The 2012 technical regulations included a large number of quite complex and specific rules regarding systems controlling the engine, clutch and gearbox. It transpires that these are simply previous technical directives being rolled up into the main package of regulations. Only the aforementioned throttle pedal maps being a new regulation to combat hot and cold blowing.
While I still try to crack that deal to make this my full time job, I do this blog and my twitter feed as an aside to my day job. In the next few weeks I plan to attend the launches and pre-season tests. If you appreciate my work, can I kindly ask you to consider a ‘donation’ to support my travel costs.
Monaco is a unique venue, not just for the layout of the circuit, but also the pit lane facilities provided to the teams. With no space for a conventional paddock and pit building, the teams park their transporters away from the small pit garages. Thus parts have to be ferried in-between the trucks and the pit, as well as parts being stored in the upper floor of the pit facility. Luckily for F1s technical observers, this presents an opportunity to see parts not normally exhibited in front of fans. Just such an opportunity presented itself to Jean Baptiste (@jeanbaptiste76) who saw Mark Webbers floor being lifted up to the mezzanine, through the crowd he was able to a quick photo of the entire assembly. From a single picture we have been to gather a lot of info on the design of Red Bulls floor. We’ve confirmed where the exhaust blows, how the trailing edge forms a flap and exclusively how the starter motor hole is blown by ducts in the upper floor. There also a wealth of detail not normally visible, although not unique to Red bull, seeing this detail is a rare treat.
Firstly we can see that this is a floor that has been run on the car, evident by the burns and dirt generated to what would otherwise be pristine black and silver floor. I suspect this is a floor assembly used for free practice, as the floor ahead of the rear tyres still sports the tyre temperature sensors. These are not typically run from qualifying onwards.
We can also see that the floor is in one complete piece, which is unusual. Normally the front t-tray splitter section is removable. Perhaps with the front splitter being lighter this season, it no longer formed of a large piece of ballast, making having a one piece floor more convenient. Plus the new more stringent splitter deflection tests are probably easier overcome with a single structural assembly, rather than two assemblies bolted to the car. Plus we can see the front bargeboards are a permanent fitment to the floor, whilst the sidepod fins are unbolted from the floor and remain attached to the sidepod fronts.
We’ve seen many pictures of the Red bull exhaust system, how it curls down to pass the exhaust along the floor towards the outer 5cm of floor aside the rear tyres. Obviously no exhausts are fitted to the floor, but the general heat protection within the engine bay appears a coating applied to the carbon floor (most likely Zircotech). Additional local heat protection is provided with separate heat shields and gold reflective sheet, under the exhaust area. The exhausts then run out of the engine bay and along the floor. Again reflective coating is used on the bare floor beneath.
We can then see the exhaust exits to the edge of the tyre decks 9the small section of floor between the tyre and diffuser. This area is extensively cut away and the edge of the floor is a metallic part which curls up to encourage the exhaust to pass beneath the floor and into the diffuser. We have seen from pre-season (http://scarbsf1.wordpress.com/2011/02/02/red-bull-rb7-open-fronted-exhaust-blown-diffuser/) that the exhaust curls up into the outer top half of the diffuser, further proven by the additional heat protective coating applied in this area. Recent pictures of the Ferrari being craned away in Spain, show that Ferrari do not shape the floor to encourage as exhaust flow to pass under the floor, McLaren are also more similar to Ferrari than Red bull in this regard. As of Monaco 2011, Red Bull were the only team to passing the exhaust flow under the outer edges of the floor towards the diffuser.
Trailing edge flap
Red Bull switched to a revised diffuser at the Chinese GP, this exploited a new treatment to the top trailing edge of the diffuser. Rather than a simple Gurney, the team formed a flap above the trailing edge in-between the rear wing endplates. This was not a new feature in F1, Toro Rosso launched their car with just such a flap and historically many cars have sported the detached gurneys of flaps. The Arrows cars in the 2000s sported just such devices. Completely legal, these simple aerofoil sections of bodywork, sit within the allowable area for bodywork at the rear of the car. Much like the gurney, these devices aim to use the high pressure air moving over the diffuser to create a low pressure region above the diffuser exit, to drive more flow out of the diffuser beneath. Effectively making the diffusers exit area larger than a simple exit.
Blown starter hole
What’s most interesting from Jean Baptistes picture are the two ducts set into the floor ahead of the diffuser. Looking closer we can see these two inlets, lead to ducts that pass inside the engine bay and either side of the starter motor tube. The starter motor hole in the boat-tail of the diffuser is a wide slot, so I believe these ducts blow the starter motor slot. Until other teams cottoned on to Newey’s exploitation of the outer 5cm of floor, most teams pointed their exhausts towards the Starter Motor Hole (SMH), as a way of using the high velocity exhaust gas, to drive more flow through the diffuser and thus create lower pressure for more downforce. With Newey’s outer blown diffuser he could not exploit the large SMH with his exhausts, so this solution allows him to exhaust-blow the diffuser and passively-blow the SMH. By passive-blowing, I mean the exhaust is not used to blow the SMH, but simply the normal airflow over the car. Of course the effect of this passive blowing is dependant on the airflow approaching the ducts inlets. The RB7 has all enclosing bodywork around the gearbox and floor. So airflow could not directly lead to the SMH. So Newey has had to duct flow to this area. It’s unlikely that the flow arriving at these ducts is that powerful, having had to pass around the sidepods and over the fairings covering the exhausts. This is likely to be a small aero gain, albeit one that other teams with similar gearbox fairings could employ. Should the engine mapping ban make the outer blown diffuser solution too sensitive to throttle position, then this duct could receive the exhaust flow to still provide a degree of blown diffuser.
Away from the unique Red Bull features, the floor exhibits a lot of standard practice for contemporary F1 floors. In Red Bulls case the floor completely encloses the underneath of the car, only a small open section in the t-tray splitter is open. This opening will be enclosed when the plank is fitted to the car. There’s probably a matching section of ballast attached under the chassis that fits in the hole, allowing the ballast to sit a precious few millimetres closer the ground.
With other teams more sections of the floor above the plank are open, and in some cases the base of the monocoque also forms the floor, so the removable floor section has even larger openings.
The area forming the front lower leading edge of the floor also has to house the Side Impact Tubes (SITs). Clearly with a one piece floor like this, the floor cannot be removed with the SITs still attached to the monocoque. Many teams have the SITs removed with the floor, by unbolting them at the side of the monocoque. This would appear to be the case the RB7 floor. Although not visible in this photo, presumably the removed SITs remain with the car, so possibly this floor is being changed, rather than stored temporarily for refitting.
Such is the tight packaging of the area within the sidepods; space for electronic boxes is limited. We can see a small black box and loom within the enclosed section of floor. Just to the rear of this there appears to be a blue-grey square set into the floor. This is probably a transparent window for sensors to project through, most likely the ride height sensors. Normally three are fitted, one to the left one the right and another at the front or rear, these three ride heights can be extrapolated to provide the engineer with the cars attitude to the track.
There is also a reasonable amount of wiring loomed around different areas of the floor. When wiring was seen dangling from Vettels front wing mounts earlier this year, people were quick to assume, this related to wing flex. But instead a lot of the car is instrumented, both for data acquisition but also troubleshooting during the race. In the case of the floor, two measurements are commonly taken, pressure and temperature. Pressure sensors log the pressure beneath the floor, should a car suffer damage in the race, the team can tell from the telemetry if a change in pressure readings are likely to cause handling problems. Equally teams have been known to fit temperature sensors the titanium fasteners holding the plank to the chassis. If these skid blocks, ground too frequently they will heat up. This delta in temperature will alert the team that the plank might be suffering undue wear and cause legality problems in scrutineering.
More pictures from @Jeanbaptiste76
Finally the FIA have published the detail of the 2011 technical regulations. There were no major surprises amongst the rules. There being rules to effectively ban: double diffusers, F-ducts & slotted rear wings. Newly introduced were the mandated weight distribution and adjustable rear wing.
There’s a lot to cover, so I wont cover every rule change and neither can I cover them in detail. but here’s the main points (with the rule in italics).
The full FIA regulations are detailed here: FIA F1 2011 Technical Regulations
Another route to banning F-ducts, as well as a move to limit the ever expanding rear fin, the rule prevents any bodywork reaching the rear wing.
“3.9.1 No bodywork situated between 50mm and 330mm forward of the rear wheel centre line may be more than 730mm above the reference plane.”
With the exception of the central 15cm, the beam wing cannot have a slot that widens internals to create a blown slot. Only Williams raced this last year, but the practice has prevented. This reinforces the fundamental rule that the lower wing should only be formed of one element
“3.10.1 Any bodywork more than 150mm behind the rear wheel centre line which is between 150mm and 730mm above the reference plane, and between 75mm and 355mm from the car centre line, must lie in an area when viewed from the side of the car that is situated between 150mm and 350mm behind the rear wheel centre line and between 300mm and 400mm above the reference plane. When viewed from the side of the car no longitudinal cross section may have more than one section in this area.
Furthermore, no part of this section in contact with the external air stream may have a local concave radius of curvature smaller than 100mm.
Once this section is defined, ‘gurney’ type trim tabs may be fitted to the trailing edge. When measured in any longitudinal cross section no dimension of any such trim tab may exceed 20mm.”
Ban on slots in the rear wing
As with the beam wing, the upper rear wing is prevented from having slots extending beyond the central 15cm. This prevent F-ducts or other blown slots, the latter which have been exploited for several years.
“3.10.2 Other than the bodywork defined in Article 3.10.9, any bodywork behind a point lying 50mm forward of the rear wheel centre line which is more than 730mm above the reference plane, and less than 355mm from the car centre line, must lie in an area when viewed from the side of the car that is situated between the rear wheel centre line and a point 350mm behind it.
With the exception of minimal parts solely associated with adjustment of the section in accordance with
Article 3.18 :
- when viewed from the side of the car, no longitudinal cross section may have more than two sections in this area, each of which must be closed.
- no part of these longitudinal cross sections in contact with the external air stream may have a local concave radius of curvature smaller than 100mm.
Once the rearmost and uppermost section is defined, ‘gurney’ type trim tabs may be fitted to the trailing edge. When measured in any longitudinal cross section no dimension of any such trim tab may exceed 20mm.
The chord of the rearmost and uppermost closed section must always be smaller than the chord of the lowermost section at the same lateral station.”
The number, thickness and cross-section of the rear wing support pylons are now more tightly controlled.
“3.10.9 Any horizontal section between 600mm and 730mm above the reference plane, taken through bodywork located rearward of a point lying 50mm forward of the rear wheel centre line and less than 75mm from the car centre line,
may contain no more than two closed symmetrical sections with a maximum total area of 5000mm2. The thickness of each section may not exceed 25mm when measured perpendicular to the car centre line.
Once fully defined, the section at 725mm above the reference plane may be extruded upwards to join the sections defined in Article 3.10.2. A fillet radius no greater than 10mm may be used where these sections join.”
Clarification of the starter motor hole
“3.12.7 No bodywork which is visible from beneath the car and which lies between the rear wheel centre line and a point 350mm rearward of it may be more than 125mm above the reference plane. With the exception of the aperture described below, any intersection of the surfaces in this area with a lateral or longitudinal vertical plane should form one continuous line which is visible from beneath the car.
An aperture for the purpose of allowing access for the device referred to in Article 5.16 is permitted in this surface. However, no such aperture may have an area greater than 3500mm2 when projected onto the surface itself and no point on the aperture may be more than 100mm from any other point on the aperture.”
Due to a previous weakness in the rules defining the underfloor, teams were able to exploit this to create the double diffuser. Double diffusers were only possible as an opening could be created in the gap been the reference plane, step plane and the diffuser. Now the rules close this avenue off.
Additionally this opening allowed teams to open up the front of the diffuser to blow the exhaust through for an even greater blown diffuser effect. This rule also prevents this opening in all but the outer 50mm of the split between the diffuser and the floor.
One additional clarification is that the suspension must not form any of the measured point for the under floor. Previously the minimum height was exploited by some teams placing wishbones or Toe-Control arms across the top an opening in the diffuser.
“3.12.9 In an area lying 450mm or less from the car centre line, and from 450mm forward of the rear face of the cockpit entry template to 350mm rearward of the rear wheel centre line, any intersection of any bodywork visible from beneath the car with a lateral or longitudinal vertical plane should form one continuous line which is visible from beneath the car. When assessing the compliance of bodywork surfaces in this area the aperture referred to in Article 3.12.7 need not be considered.
3.12.10 In an area lying 650mm or less from the car centre line, and from 450mm forward of the rear face of the
cockpit entry template to 350mm forward of the rear wheel centre line, any intersection of any bodywork
visible from beneath the car with a lateral or longitudinal vertical plane should form one continuous line
which is visible from beneath the car.
3.12.11 Compliance with Article 3.12 must be demonstrated with the panels referred to in Articles 15.4.7 and
15.4.8 and all unsprung parts of the car removed.”
Even though the loop holes in the rear wing regulations have been closed, this additional new regulation prevents the driver influencing aerodynamics. So that other driver controlled F-duct type devices cannot be exploited other areas, such as: front wings, sidepods or diffuser.
“3.15 With the exception of the parts necessary for the adjustment described in Article 3.18, any car system, device or procedure which uses, or is suspected of using, driver movement as a means of altering the aerodynamic characteristics of the car is prohibited.”
Ban on movable splitters
As with some other rules, this is a 2010 clarification now added to the regulations. Its thought that teams were allowing their splitter to flex upwards, to allow the car to run a more raked attitude and lower front wing ride height. There are now more stringent tests and restrictions on the splitter support mechanisms.
“3.17.5 Bodywork may deflect no more than 5mm vertically when a 2000N load is applied vertically to it at three different points which lie on the car centre line and 100mm either side of it. Each of these loads will be applied in an upward direction at a point 380mm rearward of the front wheel centre line using a 50mm diameter ram in the two outer locations and a 70mm diameter ram on the car centre line. Stays or
structures between the front of the bodywork lying on the reference plane and the survival cell may be present for this test, provided they are completely rigid and have no system or mechanism which allows non-linear deflection during any part of the test.
Furthermore, the bodywork being tested in this area may not include any component which is capable of allowing more than the permitted amount of deflection under the test load (including any linear deflection above the test load), such components could include, but are not limited to :
a) Joints, bearings pivots or any other form of articulation.
b) Dampers, hydraulics or any form of time dependent component or structure.
c) Buckling members or any component or design which may have, or is suspected of having, any non-linear characteristics.
d) Any parts which may systematically or routinely exhibit permanent deformation.”
Driver adjustable rear wing
The driver adjustable front wing is now deleted from the rules and instead the rear wing is now driver adjustable. This is because the expected benefit of greater front wing angle never provided the driver with more grip when following another car. The front flap adjustment was much more a solution to tune the cars handling in between pitstops. The TWG found that the loss of drag from the rear wing was a more effective solution to allow the following to overtake. Now the rear wing flap can pivot near its rear most point and open the slot gap from 10-15mm to up to 50mm. Opening this gap unloads the flap and reduced both downforce and drag.
This being controlled by the timing gap to the car ahead and managed by the FIA. So there’s two ways the driver can use the system. Firstly in free practice and qualifying the rear wing is solely at the control of the driver. They can adjust the wing at any point on the track and any number of times per lap. So for the ideal lap time, as soon as the car is no longer downforce dependant (straights and fast curves) the driver can operate the wing, just as they did with the F-duct. Although a small complication to the driving process, at least their hands remain on the wheel and not on a duct to the side of the cockpit.
Then in the race the wing cannot be adjusted for two laps, then race control will send signals to the driver via the steering wheel, such that when they’re 1s or less behind another car at a designated point on the circuit, the rear wing can be trimmed out. The wing returns to the original setting as soon as the brakes are touched.
“Furthermore, the distance between adjacent sections at any longitudinal plane must lie between 10mm and 15mm at their closest position, except, in accordance with Article 3.18, when this distance must lie between 10mm and 50mm.”
3.18.1 The incidence of the rearmost and uppermost closed section described in Article 3.10.2 may be varied whilst the car is in motion provided :
- It comprises only one component that must be symmetrically arranged about the car centre line with a minimum width of 708mm.
- With the exception of minimal parts solely associated with adjustment of the section, no parts of the section in contact with the external airstream may be located any more than 355mm from of the car centre line.
- With the exception of any minimal parts solely associated with adjustment of the rearmost and uppermost section, two closed sections are used in the area described in Article 3.10.2.
- Any such variation of incidence maintains compliance with all of the bodywork regulations.
- When viewed from the side of the car at any longitudinal vertical cross section, the physical point of rotation of the rearmost and uppermost closed section must be fixed and located no more than 20mm below the upper extremity and no more than 20mm forward of the rear extremity of the area described in Article 3.10.2 at all times.
- The design is such that failure of the system will result in the uppermost closed section returning to the normal high incidence position.
- Any alteration of the incidence of the uppermost closed section may only be commanded by direct driver input and controlled using the control electronics specified in Article 8.2.
3.18.2 The adjustable bodywork may be activated by the driver at any time prior to the start of the race and, for the sole purpose of improving overtaking opportunities during the race, after the driver has completed a minimum of two laps after the race start or following a safety car period.
The driver may only activate the adjustable bodywork in the race when he has been notified via the control electronics (see Article 8.2) that it is enabled. It will only be enabled if the driver is less than one second behind another at any of the pre-determined positions around each circuit. The system will be disabled by the control electronics the first time the driver uses the brakes after he has activated the system.
The FIA may, after consulting all competitors, adjust the above time proximity in order to ensure the stated purpose of the adjustable bodywork is met.”
Along with the supply of Pirelli control tyres they will be matched to a mandatory weight distribution. Now the cars minimum weight is 640Kg, the specified minimum axle weights, equate to a weight distribution ranging between 45.5-46.7% on the front axle. This is a few percent behind the typical 2010 loadings.
“4.2 Weight distribution :
For 2011 only, the weight applied on the front and rear wheels must not be less than 291kg and 342kg respectively at all times during the qualifying practice session.
If, when required for checking, a car is not already fitted with dry-weather tyres, it will be weighed on a set of dry-weather tyres selected by the FIA technical delegate.”
Double wheel tethers
For safety a doubling of the wheel tethers has been regulated. Each tether needs to pass through a different suspension member and have its own mounting points on the upright and the chassis. There’s not expected to be any performance impact with this. But the tethers are somewhat heavier, so they and the side intrusion panel are part of the reason for the greater minimum weight limit.
“10.3.6 In order to help prevent a wheel becoming separated in the event of all suspension members connecting it to the car failing provision must be made to accommodate flexible tethers, each with a cross sectional area greater than 110mm². The sole purpose of the tethers is to prevent a wheel becoming separated from the car, they should perform no other function.
The tethers and their attachments must also be designed in order to help prevent a wheel making contact with the driver’s head during an accident.
Each wheel must be fitted with two tethers each of which exceed the requirements of 3.1.1 of Test Procedure 03/07.
Each tether must have its own separate attachments at both ends which :
- are able to withstand a tensile force of 70kN in any direction within a cone of 45° (included angle) measured from the load line of the relevant suspension member ;
- on the survival cell or gearbox are separated by at least 100mm measured between the centres of the two attachment points ;
- on each wheel/upright assembly are located on opposite sides of the vertical and horizontal wheel centre lines and are separated by at least 100mm measured between the centres of the two attachment points ;
- are able to accommodate tether end fittings with a minimum inside diameter of 15mm.
Furthermore, no suspension member may contain more than one tether.
Each tether must exceed 450mm in length and must utilise end fittings which result in a tether bend radius greater than 7.5mm.”
After the static front wheel fairings that abounded in 2009, were banned and the wheel design homologated, there must have been some surprise that Ferrari managed to create an aerodynamic wheel shape in 2010. This is partly limited now by the restriction on surface area for spokes and shaping. The limited only allows 13% of the wheel centre to be spoked, meaning that a ten spoke wheel has to have spokes just 16mm wide.
“12.4.6 When viewed perpendicular to the plane formed by the outer face of the wheel and between the diameters of 120mm and 270mm the wheel may have an area of no greater than 24,000mm2.”
Clarification of mirror positions
Again when the FIA clarify a rule or make a change for safety reasons, we don’t get to see the detail of this change until its put into the regulations. The removal of outboard mirrors was brought in early last year and now the mirrors can effectively be no more than 27.5cm from the cockpit opening
“14.3.3 All parts of the rear view mirrors, including their housings and mountings, must be situated between 250mm and 500mm from the car centre line and between 550mm and 750mm from the rear edge of the cockpit entry template.”
Mercedes surprised many with their blade-like roll structure, reducing the obstruction to the rear wing and allowing for a much shorter inlet tract for the engine, the solution was likely to be copied. A minimum cross section forced teams to have a wider section above the drivers head, negating the fundamental benefit of the solution
“15.2.4 The principal roll structure must have a minimum enclosed structural cross section of 10000mm², in vertical projection, across a horizontal plane 50mm below its highest point. The area thus established must not exceed 200mm in length or width and may not be less than 10000mm2 below this point.”
With the cockpit opening fixed at 550mm, teams have often raised the front of the chassis around the dash bulkhead to create a raised nose. In the first of several limits for both 2011 and 2013, with even more stringent plans for 2013, the height of the front of the chassis is now being controlled. The limit for this point is now 670mm, still some 120mm above the cockpit opening.
“15.2.3 The highest point of the second structure may not be more than 670mm above the reference plane and must pass a static load test details of which may be found in Article 17.3.”
As already explained teams raise the position of the front (AA) and dash (BB) bulkheads to create space under the nose for airflow to pass in between the front wheels and reach the rear of the car. The trend for “V” sections noses, introduced on the Red Bull RB5 in 2009, makes the front of the chassis even higher, often being visible above the height of the front tyres (~660mm). Now both these bulkheads need to be at 625mm, some 75mm above the cockpit opening.
“15.4.4 The maximum height of the survival cell between the lines A-A and B-B is 625mm above the reference plane.”
Limit on shaped Rear Impact Structures
Since the 2009 aero rules, teams have been shaping the rear impact structures into ever more curved shapes to lift it clear of the diffuser and pass it underneath the beam wing. The tail of this structure must be centred at 300mm high, to prevent extreme banana shaped structures, this rule forces the structure to vary by no more 275mm.
“Furthermore, when viewed from the side, the lowest and highest points of the impact absorbing structure between its rear face and 50mm aft of the rear wheel centre line may not be separated vertically by more than 275 mm.”
F1 cars suspension tends to adopt similar formats both front & rear and across the teams. Ride height and springdamping is provided by a pushrod (or Pull rod for Red Bulls rear suspension, which is the same but inverted) which operates a rocker, this rocker has levers operating the torsion bar spring, damper and third (or heave) damper. Ride height it set by the angle of the torsion bar on its splines and fine tuned by the shims in the pushrod. Ride height does get controlled by the heave damper, but only when high aero loads compress the suspension at high speed, as the heave damper has some free travel before it starts to add stiffen the suspension it cant be used for adjusting static ride height. The individual wheel dampers do apply some pressure to the suspension when at rest, but aren’t commonly used for setting ride height.
In this weekends race Petrov retired with e a suspension problem, it transpires the ride height adjusting shim fell out between the carbon pushrod and the titanium end fitting, Here James Allison explains “On lap 11, Vitaly reported that the car wasn’t behaving normally and he began losing a lot of lap time to Barrichello. We called him into the pits for a precautionary check and found a problem with the right-front suspension pushrod that forced us to retire the car. Upon further investigation, it transpired that the pushrod had been touching on the chassis when running on very heavy fuel at the start of the race. This damaged the bolt that attaches the pushrod to the car, and meant we lost a shim from the suspension, causing the DNF. Robert preferred a slightly different ride height and was fortunate not to encounter the same problem. We are, of course, disappointed that we did not discover this problem during pre-season testing. The parts in question will be modified for the next race to ensure that it cannot recur.”
At the top of the pushrod You can see where it splits to allow the shim to be inserted
The ban on refuelling was originally envisaged as a method to liven up the show, forcing drivers to overtake rather than wait for pitstops. Making the cars fuel tanks big enough to house the 170+ kg of fuel for a race distance has been a well publicised challenge. But there’s another facing the teams brought in by the rule change. How the cars handling changes with the ever lightening fuel load.
Its been a long time since F1 cars had to run without refuelling. Since then the car have raced with 60-80kg of fuel on board, burned it off over 20-30 laps and then take on another tankful. Now teams will start with 170kg of fuel and burn it off over the course of the entire race. With F1 cars dry weight just 610Kg this is now a substantial proportion of the cars weight. This extra weight will press down on the cars suspension pushing it closer to the ground. Thus the cars ride height will alter considerably from the start of the through to the end. Ride height is critical for two reasons; the overriding issue is aerodynamic. Firstly the front wing and diffuser work in ground effect, so they work better the closer to the ground they get. Thus the wings will work better at the start of the race and diminish as the fuel load lightens. Secondly ground clearance, the plank and titanium skid blocks will be prone to wearing when the car is heavy, excessive wear on the skid blocks will render the car illegal in post race scrutineering.
The teams will need to set the car up to work over a wide range of ride heights, this will mean compromises somewhere, making the car better at high or low ride.
Making matters more complicated will be the return to low fuel final qualifying, the cars wil enter Parc Fermé on Saturday all but empty, then they will be fully fuelled before the race. Again do the teams make their set up favour low fuelhigh ride height qualify or go for heavy fuel low ride height for early race pace, or pick a point somewhere in between? Every track will favour certain compromises. Monaco is the classic example of a set up compromised towards qualifying, so teams will focus on the lighter fuel settings, but remain conscious that plank wear can be high over the principalities bumps and kerbs.
One solution put forward was ride height adjustment made during the race. Since the ban on active technologies in the nineties, the rules are clear, there can be no adjustment of the cars suspension while it is moving, equally parc ferme rules prevent any changes between qualifying and the race. But teams could have a mechanic adjust the ride height during the pitstops.
This would be legal and feasible, as the pushrods or torsion bar mounting could be fitted with a quick adjustment mechanism. Even within a sub 3 second pitstop, this could be completed accurately. But as the car will start the race with qualifying (low fuel) ride height settings, this could not be adjusted until the first pitstop, thus the opening stint would be compromised by the wring ride height. Of course the balance of the race could then follow the ride height with the decreasing fuel load, but adjusting at the second and subsequent stops.
How could this be done?
Teams generally adjust ride height with shims fitted to the pushrods. The pushrod is split between the main shaft and the metal end fitting, by loosening the bolts that tie them together a shim can be added into the gap. Thicker shims mean more ride height and the shims need to be added to each of the four pushrods (two front two rear) to gain a balanced ride height. Adjusting via this method is impractical during a rapid pit stop. The pushrods could have a threaded adjuster as used on the front wing flap, a turn of the adjuster drops ride height by a fixed amount, this would be quicker to adjust, but still all four relatively in accessible (during a hectic pitstop at least ) would be difficult.
More likely would be to rotate the fixed ends of the torsion bar springs, by fitting the torsion bars on each axle to a common mechanism, they could be quickly adjusted by a single adjuster (two in total for the car) accessible through the top of the chassis or gearbox. Although the latter would be still hard to access shrouded by the rear wheels and rear wing, plus the associated wheel change and jack mechanics.