Williams: Canadian Low Drag Rear Wing

Every year at low Drag circuits some teams will try a more radical way to reduce downforce and drag from their rear wing. It’s rare these solutions get to race, as teams invariable end up running more downforce than the barest minimum these special wings provide. This year Williams bucked that trend and have an all new low drag rear wing. Williams have gone for an opposite strategy to last years (https://scarbsf1.wordpress.com/2011/06/11/renault-wiliams-complex-low-drag-wings-for-canada/) and have created the wings downforce towards the tips of the wing and not the centre.

Mercedes: Are they blowing the Front or Rear wing?

Update on how it links to the front wing

Original article/

I’ve heard a lot of reporting about the Mercedes F-Duct stalling the rear wing and the likelihood of other teams already having a similar system.

I can see the logic in why people think that the DRS controlled duct blows the rear wing elements in a bid to reduce drag. I haven’t seen any evidence of this being the case; equally I can see several issues with this theory. The problem with the theories on the DRS duct stalling the rear wing are twofold; firstly the DRS is already cutting immensely, secondly the rules greatly restrict the ability to stall the rear wing. Back in to 2010 teams were using blown slots across the full width of the rear wing, these being used with perpendicular blowing to stall the wing or tangential blowing to act as an additional slot gap for more downforce. The rules introduced in 2011 aimed to prevent both of these types of slot.
To stall either the top rear wing or the beam (lower) rear wing, you need to blow a slot. In the post 2010 rules, slots are banned in any section of the rear wing (via a 100mm minimum radius rule); this ban applies to all three wing elements aside from the middle 15cm. So to use the DRS duct to blow a rear wing slot, all you’ll stall is the very centre section of wing. This area creates very little induced drag (most of that’s created at the wing tips), so stalling it will not improve top speed by much. Thus it will provide very little benefit.

It’s possible the DRS Duct could stall the flow around the sidepod, exhaust or diffuser. I’ve got no information on this, or a valid reason how this would benefit the aero. In my opinion the blowing to stall the front wing is still the most valid theory.  Pictures have merged today of Schumachers car lifted on a crane that shows the slot sunder the front wing. other pictures also show close ups of the rear of the car, do not show any slots in the top or beam wings.

Search on sutton images for pictures d12aus3468.jpg, d12aus3467.jpg, d12aus3465.jpg

I suspect the two ducts leading from the beam wing into the engine cover are part of the system.  Either taking the DRS-duct flow to the front wing directly, or by using the DRS-duct to switch the F-Duct.  I can;t find where the F-duct switch is sited, perhaps inside the rear wing, in which case the two beam wing ducts might be of different uses, one feeding high pressure airflow to the F-Duct and the other feeding the flow to the front wing.  As this is an evolving theory, I’ll post more on this system as we start to understand it better.

I’ve looked at the McLaren, Red Bull and Ferrari rear wings, as yet I can see no shaping to suggest a DRS-Duct is packaged inside the endplates.  There’s little doubt these teams must be working on similar solutions.  Although Red Bull and Lotus may probably not be developing this solution, as they are now querying the FIA on its legality LINK

We have now acceptance by the FIA that the DRS duct is legal, that Mercedes  are running this system and pictures show the duct emerging from the beam wing reaching forwards inside the engine cover. Presumably, to reach towards the front-end of the car. No doubt more information will soon emerge on these systems.

other links:

DRS open showing the duct open beneath the flap (via AMus)

LINK

Rear wing no sign of any slots in the middle 15cm

LINK

Mercedes: F-Duct Front Wing operated by the Rear Wing DRS

Update on how it links to the Front wing

Update

Something often said of banned developments in F1, is that once understood no solution can be unlearnt. So while the FIA fights to ban technologies that they feel aren’t suited to F1, the teams will always try to apply that solution in a different way.
McLaren understood how to stall a wing by blowing a slot perpendicular the wings surface. This knowledge lead to the F-duct in 2010, as you will recall the FIA moved to ban slots in the rear wing and direct driver interaction with the cars aero. But the knowledge of blown slots to stall wings has remained and it’s been Mercedes who have been busy trying to apply it in other ways. This culminated with the tests of an F-Duct front wing late last year. Rumours continue to fly about the teams use of the F-Duct front wing (FDFW) in 2012. I understand the 2012 Mercedes AMG W03 does have an F-Duct front wing and this is operated by the rear wings DRS. Based on information I have from the sources around the team, and from looking at the cars performance and construction mean I can speculate how and why Mercedes might be using the FDFW.

As detailed in two articles last year, Mercedes are believed to have run blown slots under the front wing to stall the wing at higher speeds. Three reasons came up as to why this would be used; reducing drag, managing wing ride height and managing the cars aero balance. With nothing official being said by Mercedes, we were left unsure as to exactly why a passive FDFW would benefit the car.
https://scarbsf1.wordpress.com/2011/10/21/mercedes-f-duct-front-wing/

https://scarbsf1.wordpress.com/2011/10/24/update-mercedes-f-duct-front-wing/

Some observations from the Mercedes team last year might aid us in putting a picture together of how the 2012 solution might benefit. Mercedes were the first team to really exploit more of the open DRS effect and use a short chord flap. The open DRS boosted Mercedes top speed and could be used through the lap in qualifying. Despite this benefit the teams did struggle in qualifying, their race performances latterly became better than qualifying suggested. It was clear for Michael Schumacher at Least, that the cars handling wasn’t ideal and the team sought to resolve the cars nervousness.
Bearing these points in mind, the potential benefits of a FDFW become more apparent. Mercedes need more qualifying pace; they can exploit their DRS more frequently during qualifying, but in higher speed turns the cars lacks the balance for the drivers to fully commit through the turn.
If they can cure these issues, then they will further up in qualifying and able to take the fight to the leading teams. I now believe the FDFW works to manage the cars balance in high speed turns when the DRS is activated. As DRS reduces both rear drag and downforce, the car becomes unbalanced in downforce front-to-rear. In other words pointy or oversteering. Which in high speed turns in qualifying is hard to handle. At higher speeds even with DRS reducing rear wing downforce, the car has enough downforce to make it around corner, the problem is how to make the car more balanced front-to-rear when DRS is activated.
The FDFW we saw last year appeared to be passive, this uses nothing other than airspeed to trigger the slot to blow enough to stall the front wing. If matched to the speed DRS would be used at (in qualifying), the passive FDFW would help balance the car, by reducing front downforce to match that of the rear. However the front wing would always stall at these speeds, whether DRS was in use or not, so outside of qualifying the wing would stall and the car would understeer. With Parc Fermé rules in force, the team cannot change the FDFW between qualifying and the race.
Another issue with the passive FDFW, is that under braking as air speed reduced, the wing would need time to start working again. But this early phase of braking is just when the driver needs the most downforce. What the FDFW ideally needs is a method to link its activation to that of DRS, in other words an active F-duct.
As we’ve already mentioned, driver activation is not allowed, as are any other moving parts to directly alter the airflow. This brings up the Designers favourite interpretation in the rule book, primary and secondary purpose. Any part on the car can be for a primary purpose; sometimes any secondary purpose is banned or restricted. However in most cases the rules are vague and Designers are free to find secondary uses for a solution on the car. Examples of this are the cooling fans on the Brabham Fan car, the engine blowing off throttle for blown diffusers or brake torque altering ride height on the Lotus Reactive Ride Height system. In each case the first element was legal as its primary purpose was as stated, but a secondary purpose was able to be exploited.

The DRS rules are quite clear that the flap must not be shaped to allow other aerodynamic benefits. In fact this wording affects only a portion of the flap and additionally the endplate is excluded from this wording. If the team could find a way to blow into the front wing a duct when DRS is activated, then the FDFW could work synchronously with the DRS.

The hingeplate the flap mounts to, closes a hole when DRS is closed. When DRS is open the duct is revealed and the F-duct stalls the front wing

I believe Mercedes have found a way, by creating a duct through the endplate. When DRS is closed, the flap and the plate it attaches to is in a nearly vertical position. When DRS opens, the area the flap initially covered is exposed. If this area featured an opening that lead into a duct inside the endplate, when DRS opened the high pressure above the wing would force flow through the duct. With this duct then routed through the car to the front wing, when DRS is open the FDFW would be blown and stall in unison with the rear wing. Clearly when DRS closes the duct would be closed off and the duct would stop blowing the FDFW, restoring front and rear downforce.

When DRS is open, the duct passes into the beam wing and through the car. Eventually reaching the front wing slot to stall the wing.

Some evidence around the rear wing of the W03 shows this could be possible. We have to be careful to pinpoint every feature on the rear wing as being FDFW related as the DRS mechanism is hidden inside the endplate as well. Some access panels on the wing could be for DRS, FDFW or other purposes, some might be for both. In my research I’ve yet to see a clear high resolution shot of the Mercedes with DRS open, this is unusual as most other teams have been seen with the DRS in effect. Equally clear pictures of the inside of the endplate, where the flap meets the endplate, are in short supply. With this lack of material I can propose a solution, although the actual parts may diffuser is location and appearance. Its expected at this weekend Australian GP the rear wing duct will be exposed as the car uses DRS on the straights. We will need photographers with a big lens and steady hand to catch sharp pictures of the inside face of the endplate, when DRS is activated.

Evidence of the duct can be seen on the car, when the car is not moving. Clearly the W03 rear wing endplate is quite thick, an access panel that houses the DRS actuator is outboard of the flap\endplate intersection, plus there is another panel in line with the beams wings intersection with the endplate. I’d suggest the duct is opened by the flap and hinge plate, the duct then routes through the double skinned endplate down into the beam wing. This then exits through the duct that mounts the beam wing to the gearbox. There’s a tortuous route for the duct through the car to reach the front wing, but this isn’t that dissimilar to the 2010 F-Duct routing. As with McLaren in 2010, the trick is to design the duct into the car at an early stage to minimise losses through the ductwork. This usefully makes it harder, but not impossible to copy. To copy this set up the monocoque needs to be altered and the nose cone needs the apertures into the front wing mounting pylons to feed the airflow into the front wing itself. This requires time to redesign and potentially re-crash test any changes.
But, can this set up be legal? The act of stalling a front wing through a blown slot is legal, although F-ducts are banned, it’s only via the slot in the rear wing that this was achieved. Direct driver intervention is banned, but the driver is allowed to operate the DRS, so any secondary aerodynamic effect of that is not prohibited in the rules.
Although the rules allow this, it’s possible the FIA could issue a Technical Directive on the matter, that any overt secondary effect of using DRS is not allowed and the whole solution could be banned in a stroke.

With a tight and competitive season in prospect qualifying performance will be critical. Notwithstanding the potential structural work to allow the duct to pass through the car, the DRS activated F-duct Front wing is an attractive option for the other leading teams.

Launch Analysis: McLaren Mercedes MP4-27

As the first real launch of a 2012 F1 car, McLaren have unveiled their MP4-27. In McLaren parlance this was the cars “technical launch” and was carried out at their Technical Centre in Woking, UK.

2011
McLaren had one of the fastest cars in 2011, on its day the MP4-26 was faster than the Red Bull. So the basic approach of the new car did not need to veer too far from direction McLaren had been following. Last year the season was blighted by poor form in pre season testing. Most of the winter tests were interrupted by exhaust problems, as the now near mythical “octopus” exhaust broke after a few laps out on track. This exhaust turned out to be far simpler than the rumours suggested. The exhausts ran sideways across the floor to exit in a longitudinal slit ahead of the rear wheels. This being a complex way to achieve the same sort of fluid skirt that Red Bull achieved with their outer blowing exhaust layout. Once McLaren had followed Red Bulls lead with the exhaust, they were able to catch up. McLaren perhaps even surpassed Red Bull with the exhaust blown diffuser, as the Mercedes Hot Blown engine mappings were superior to the Renault cold blown solutions. Despite the rules trying cap the hot blown benefits as early the Canadian GP, the Silverstone GP weekend showed how much McLaren were lost relative to Red Bull when the restrictions really bit hard.

Philosophy
With a strong car at the end of 2011, the team have learnt about the damage a slow start to the year makes to their championship chances. This year evolution is required, McLaren do not need to find large chunks of time, but do need a car that will perform well at the opening races. Thus we see the refinement of old concepts and little in the way of radical development.
Thus the new car bred from the recent line of McLarens, the family resemblance goes further than the colour scheme. With a low nose and sweeping lines over rounded sidepods are now trademarks of the Woking design team. With the second year of the fixed weight distribution and Pirelli tyres, little needed to be done to the cars basic layout. Running much the same chassis, fuel tank size and gearbox, so the wheelbase is similar to the previous car.
Although the 2012 Pirelli front tyres are a new shape tyre, Paul Hembury from the tyre supplier confirmed to me that the change in the new profile is “not visible to the eye”. So only small optimisations of the front end aero are needed to cope with the change.

The nose-down, tail-up 'Rake' of the car is evident, with as much as 10cm of rear ride height

The studio photos of the car in side profile show off the amount of rake the car is designed to run. This is also a carry over from 2011, as the car could often be seen with a clear 10cm of ride height at the rear axle line. Although managing rake will be harder this year as the greater rear height introduces more leakage into the diffuser from the sides. As yet the teams solution to seal the diffuser are hidden by a simple floor fitted to the launch, although these are removable panels and more complex designs will soon be seen.

With so much to carry over in philosophy and design, what has changed for 2012?

MP4-27 in detail
The stand out points on the MP4-27 are the nose, sidepods and exhaust position.

Firstly the front wing is near identical to the late 2011 wing, so we can expect its general design to carry over, as will the snow plough vane below the nosecone. But the height of the nose at first appears to be at odds with the 2012 rules on a maximum 55cm height for the front of the nose.

Looking closer at McLarens chassis in side profile its clear the family history of low noses has helped here. The dashboard bulkhead is may be just 3cm higher than the cockpit padding (which is 55cm high), the chassis top then curves downwards towards the front wheels. By the point of the front (A-A) bulkhead the top is lower than 55cm, may be as low as 5cm below the maximum height. When compared to the maximum heights (the dotted line on the drawing), its clear this is a very low nose overall.

The snow plough vane under the nose might be part of the secret to a low nose

This creates less space under the raised nose, but the teams snow plough device under the nose works aggressively as a turning vane, so perhaps the team don’t need the higher chassis to get the correct airflow to the sidepods leading edge. McLaren also find the lower nose provides the classic vehicle dynamics benefits of a low CofG and a less extreme front suspension geometry. This trade off works for McLaren and goes to prove not everything in F1 has to be a compromise in search of aero advantage.

Unique drillings between the rim and spokes of the wheel aid brake cooling, the ring fairing is missing on the launch car.

Although details around the front end will change, the wheels are typically a design chosen to last for the whole season. This year the McLaren Enkei wheels sport a novel set of drillings to aid brake cooling. The usual spokes formed into the wheel between the hub and the rim, stop short and a radial set of holes are made near the rim. Although not present of the launch car, there will be a dish shaped fairing added to small pegs formed into the wheel to aid the airflow out of the wheel.

The high rectangular inlet and large undercut set the car apart from the "U" pods of the 2011

In 2011 McLaren were not afraid to try a radical sidepod set up, This was the “U” shaped sidepod, with the angled inlet shape creating channel in the upper section of sidepod (About the MP4-26 “U” shaped sidepods).  This year the team have adopted more typical sidepod format, with high\wide sidepod inlets and steep undercut beneath. I got to ask Tim Goss about this:

ScarbsF1: Can you tell us about why the concept’s changed, why you don’t feel that was a benefit this year?
Tim Goss: Last year’s U-shaped side-pod worked very well with what we were trying to achieve last year with the exhaust layout, it was all intended at creating more down wash to the rear end, and it performed particularly well last year. This year at a fairly early stage we set about a different approach to both the external and the internal aerodynamics of the car, and then once the exhaust regulations started to become a little bit clearer then it was quite obvious to us that the U-shaped side-pod no longer fitted in with both the internal aerodynamics and some of the external aerodynamics that we pursued early on. So it works, it worked very well last year, but it’s actually just not suited to what we’re trying to achieve this year.”

.

Not extreme like the "U" pod, but the sidepod tops do incline slightly

In frontal profile the high and wide cooling inlet is obvious.  The team have been able to incline the sidepod tops slightly, this isnt quite a “U”pod shape, but is quite distinctive.  At the rear the team have kept the sidepods narrow and slimmed the coke bottle shape in tightly to make the sidepod join the gearbox fairing creating a continuous line of bodywork to the very tail of the car.

the heated air from the radiators passes up over the engine and out of the central tail funnel

As well as the external airflow considerations, McLaren looked the sidepods internal airflow, they wanted a cooling exit on the cars centreline. This would have been compromised with the “U” sidepod, so the more conventional shape was selected. The cooling arrangement is similar to Red Bulls philosophy, the radiators direct their heated airflow upwards and around the engine, this then exits in a tail funnel. The launch car had quite a modest central outlet, but we can expect to see far larger versions used at hot races.

the front upper section of sidepod is switchable for version with cooling outlets

Aiding the tail funnel there are also cooling panels on the upper leading edge of the sidepod, either side of the cockpit padding and various panels arund the rear of the coke bottle shape. Different panels will be used depending the cooling and\or drag demands of the of the track.

Last years more complex roll hoop cooling inlets have been simplified into one below the engine inlet

Other cooling functions are covered by the inlet below the roll hoop. Last years double inlet set up has gone and now a single duct is used. This probably cools both the gearbox and KERS.

Viewed through the rear wing the exhaust bulge is obvious

The other notable aspect of the sidepods are the exhaust bulges. These stick out prominently on the flank of each sidepod. They don’t serve an aerodynamic function themselves, but simply fair-in the final 10cm of exhaust pipe. This final section of exhaust is now strictly controlled by the regulations. Its position must sit within specific area, it must point upwards between 10 – 30 degrees and can point sideways plus or minus ten degrees. McLaren have fixed the exhaust in the lowest most rearwards position possible, the tail pipe then pointing steeply upwards and inwards. From the limited view it would appear to direct the exhaust plume towards the outer span of the rear wing.

This would make a blown rear wing (BRW), the added flow from the exhaust aiding the wing in creating downforce at lower speeds. The exhaust position and fairing also suggests an alternative exhaust tailpipe could be used. Paddy Lowe confirmed that different solutions would be tried in testing. From overhead its clear to see the exhaust could be angled differently to blow over the rear brake ducts fairings to create downforce directly at the wheel.

The gearbox case design is not the shrunken design we saw with Williams in 2011 , the differential is low but not unduly so. The top of the case sitting neatly under the tail funnel. Pull rod suspension remains at the rear of the car, while conventional pushrod is on the front end. Lowe commented that the Lotus brake antidive system was not specifically looked at, but was part ”of a family of solutions” that has been looked at in the past. The engineers feeling that the Lotus system was illegal and hence had not been explored further. They declined to comment of the possibility of an interlinked suspension system.
Behind the gearcase, the rear impact structure is mounted midway between the beam wing and floor, fully exposing both the beam wing and allowing airflow into the central boat tail shape of the diffuser. As the diffuser was covered up, its not clear if there are features to drive airflow into the starter motor hole. A new feature on the beam wing is an upswept centre section, the extra angle of attack in the middle 15cm of the wing having a slot to help keep the airflow attached. The upper rear wing is a new design albeit similar the short chord DRS flap wing, we saw introduced at Suzuka last year. The DRS pod is still mounted atop the rear main plane and its hydraulics fed to it through the rear wing endplates. The flaps junction with the endplates follows recent McLaren practice with a complex set of vents aimed at reducing drag inducing wing tip vortices.
Not much else in terms of structures or mechanical parts were evident at the launch. Lowe did confirm to me that the Mercedes AMG KERS remained packaged under the fuel tank in one assembly. Also adding that there would not be an significant weight loss to the system.  As a significant reduction in weight was made between the 2009 and 2011 season, via the consolidation of the Batteries and Power Electronics into one unit.

Mp3 of the MP4-27 Engine fire up via McLaren

F1 2012: Rules, Designs and Trends

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.

2012 noses

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.

The front section of chassis will be as high as possible (at 62.5cm) and radiussed into a "V" shape

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.

New exhausts

Exhausts must be high up on the sidepod, so cannot blow the diffuser

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.

Blown rear wing (BRW): The exhausts will blow upward to drive flow under the rear wing for more downforce

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.

A more aggressive BRW raises the exhaust and blows tangentially under the wing profile, which is more efficient

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.

An extreme but legal solution is to blow the exhaust on the rear brake duct fins creating downforce directly at the wheel.

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.

Antidive geometry in the front suspension is one way to reduce pitch 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.

An interpretation of the Lotus Antidive solution, using the brake caliper mounting to operate a hydraulic circuit and extend the pushrod (legally) under braking

These and probably other solutions will be seen in 2012 to maintain the ideal ride height under all conditions.

Front end

A three element endplate-less front wing

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 three\four 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.

Arched sections (yellow) of wing, help drive vortices to divert airflow along the car

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.

Extending the front wing mounting pylons helps to make use of the middle 50cm of wing

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).

Pointing a section of front wing profile at a suitable vane on the front brake ducts is one way gain aero performance.

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.

Sidepods
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 low\tapered, 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.

An undercut in the sidepod is one way to drive good flow around the sidepod to the diffuser

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.

Using a slight McLaren "U" shape to the sidepod may still work in 2012

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.

The tail funnel (light yellow) is a good cooling outlet method, as it reduces the size of the coke bottle section of 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.

Other aero
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.

The Coved section of floor between the tyre and diffuser will be a key design in 2012, as will cold blown starter holes and trailing edge flaps

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.

Tapered flaps and top mounted DRS pods will be a direction for 2012

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.

Structures

Variations on William low line gearbox and differential will be followed for this year

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.

Rear pull rod suspension will be all but universal this year

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.

Undercut roll hoops with internal metal reinforcement will be a common feature to drive airflow to the rear wing

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.

Analysis: Ferraris Front Wing Flutter

In free practice for the Indian GP, we saw a violent fluttering of Felipe Massa’s front wing. This is a higher frequency movement than the flex we commonly see on front wings – in fact, the movement is enough to cause the endplates to hit the ground, sending up showers of sparks. Bearing in mind that the wing is around 75mm off the ground when the car is at rest, we can appreciate the amount of movement that’s occurring here.
This movement is not an aero benefit in itself, but may be symptomatic of other flexibility in the wing.
Ferrari Flexi Wings 2011 Indian Grand Prix FP1 by Mattzel89

This clip shows the Ferrari crest the hill before braking into a turn (4s into the clip). As the car crests the hill at high speed with DRS open, it’s clear that the wing is bowed from the aero load. It’s possible to see the side spans of the wing bend down from the central section. At this point there is some vibration in the wing, but not an excessive amount. As the car starts to go down hill (DRS still open) and passes a shadow across the track, the wing starts a rocking motion (5s into the clip). This rocking soon increases in violence until Massa closes the DRS and starts to brake as usual for the corner (at 9s), so this episode only lasts three seconds. I counted around 20 movements of each endplate, which increase to the point where the endplates’ skid blocks strike the ground.
The cause may be explained as follows: the wing is bowed at speed, but as the car crests the hill the wing is unloaded slightly. Then, as the car starts to move down hill, that load would reverse and the wing (which was already vibrating) is sent into a rocking motion. One endplate moves down, while the centre section and wing mounting pylons appear to be rigidly fixed to the car and are not moving. The load passing from the endplate must have been transferred across the central spar of the wing to the other endplate, which now drops. This movement resonates in a wave from one side of the wing to the other, increasing in frequency and amplitude until the wing actually hits the ground.
I can’t explain why closing the DRS and braking calmed this resonance so quickly, but the wing rapidly returns to the low-amplitude, high-frequency vibration seen elsewhere on track.
Also, I’m no expert on composites but my limited knowledge does suggest that carbon fibre structures are relatively well damped (compared to, say, a metal structure), the rebound effect of flex being relatively well damped and not prone to oscillating.
Ferrari introduced the new front wing in Korea. Alonso ran the wing as it was clear that it displayed the accepted level of flex as used by many other teams. The wing is legal as it meets the more stringent FIA 2010 deflection test. Last year Red Bull set a precedent when its wing, which openly appeared to bow downwards at speed, passed the tests and was declared legal, even when the test loads were increased mid-season.
This bowing effect – where the tips of the wing move downwards at speed – is commonly used as the front wing then sits closer to the ground and can generate more downforce. Despite a lot of theories about mechanisms or heat being responsible for the flex, the answer is much simpler: it is down to the way you want the wing to work i.e. the tips to bend down without the wing twisting and thereby reducing the wing’s angle of attack. This is all done with the lay-up of the composites – I’m told it is a “nightmare“ and have heard of composites technicians spending weeks trying different lay-ups to get this effect, but once worked out it is very effective.
Of course F1’s knowledge of carbon structures has been used to create very stiff parts, but now that we are starting to allow controlled flex, we will start to see resonance becoming an issue. There is a new field of knowledge to be understood and controlled.
It seems the wing was tried again in FP3 and the FIA has taken an interest in the wing. The wing was removed and one would assume that it will not be raced for fear of mechanical failure or a post-race ban, although Ferrari’s Friday press release may suggest that the wing is a development item not planned for use in the race, but as part of the 2012 programme. Pat Fry: “We continued with the now usual parallel programmes: on the one hand looking for the best set-up for the car at this circuit and on the other, working to get a greater understanding of the latest aerodynamic updates, with the new car project in mind.”
We have seen extreme movement of front wings before in super slow motion, such as wing tips fluttering, wings swaying sideways on their mounting pylons and endplate devices flapping. All of these movements, although highly visible, have been accepted by the FIA because the tests have been passed. All of which is to the detriment of the overriding regulation that bodywork should be rigid and immovable.

Thanks to Andrew Biddle (andrewbid@gmail.com) for his assistance as Copy Editor

McLaren: Suzuka upgrades and design overview

McLaren have proven to be Red Bulls nearest competitor for most of the season. While not quite having the same raw pace as the RB7, the MP4-26 is as fast on race day and arguably can be easier on its tyres. Having started with two bold concepts the “U” shapes sidepods and the mysterious “Octopus” exhaust, the design had to be compromised to ditch the complex exhaust and revert to a Red Bull style outer blown diffuser. Leaving McLaren with a large amount of space under the gearbox, that was supposed to package the exhaust. This left the car with a higher rear CofG without the benefits of the exhaust to offset it. So it’s been remarkable that McLaren have been able to morph the initial concept into a race winning, Red Bull baiting package.
The pace of development never slows, So McLaren arrived at Suzuka with a new diffuser detail and another iteration of its Silverstone short-chord rear wing.

Following a lot of the rest of the paddock , McLaren added a diffuser flap across the top edge of the diffuser exit. The flaps profile only being broken by a large gurney flap under the rear crash structure. As already discussed in the Red Bull Monza diffuser article (https://scarbsf1.wordpress.com/2011/09/22/red-bull-monza-diffuser-analysis/), this flap is an evolution of the trailing edge gurney, used to create lower pressure aft of the diffuser for more downforce. McLaren can run such a large central gurney flap as it sits in a 15cm window in the bodywork rules that allow taller bodywork. Its also beneficial as the raised rear crash structure (for the “octopus” exhaust) allows a good airflow to pass underneath it towards the gurney.

Again we saw McLaren run the short chord DRS rear wing, allowing the team to use the DRS more frequently during qualifying runs. This wing has already been detailed in the blog (https://scarbsf1.wordpress.com/2011/07/14/mclaren-new-drs-rear-wing/).

Further down the car, we can see the rear brake duct cascade. Rules allow 12cm of bodywork inboard of the rear wheels, there is no stipulation that these function as brake cooling ducts, so teams exploit this for ever larger stacks of aerofoil sections to gain downforce directly acting upon the wheels.
McLaren have also altered their exhaust system over recent races, switching from a simple oval profile tail pipes, for pipes that pinch-in to form a nozzle at their exit. Also the detailing around the floor area varies by track, with more or less floor being cutaway around the exhaust exit. This alters the amount of exhaust flow passing beneath the floor to suit differing ride heights. As one of the functions of the EBD is to act to seal the diffuser, often likened to a virtual skirt. The high energy exhaust gas, prevents other airflow entering the diffuser, thus maintaining downforce.
Its no surprise given the proximity of the brake ducts to the exhaust outlets, that the lower stack of brake duct aerofoils are heat protected. No doubt some of the exhausts energy is used to drive airflow under the ducts to create more downforce.

McLaren use a split cooling outlet set up, rather than Red Bull who tend to focus all the outlet area into the large bulged exit high up on the engine cover. McLaren’s main outlets are the exit to the sidepods coke bottle shape. With outlet area to the side of, and above the gearbox. This is aided by 3-slotted louvers on the flanks of the sidepods.

Lastly McLarens unique sidepod design is clear to understand from this angle. The “U” pods create a path for the airflow passing over the centre of the car, to reach the rear wing relative unobstructed. Typically airflow closer to the cars centreline is cleaner and has more energy. This is why designers tend to use this airflow to feed the sidepods for cooling purposes. What McLaren have done is to compromise on the cooling efficiency for greater rear wing performance. The small fin inside the channel is used to create a vortex to main the airflows energy and direction through the channel.

Analysis: McLarens Rear Wing Vapour Trails

Picture courtesy of F1Pulse

A feature of F1 for many years were the vapour trails spiralling off the rear wing tips. This phenomenon largely disappeared a few years ago, but was apparent once more on the rear wings of the McLarens at the recent damp race weekends. So what are these vapour trails and why do McLaren tend to create them more than other teams?

They are in fact more correctly termed ‘vortices’, they are created when the pressure differences are created at the wing tip. As you get high pressure above the wing, low pressure beneath and near ambient pressure to the side of the endplate. When these three flows meet, the higher pressure flow naturally moves towards the low pressure areas. This sets up a tumbling motion and a spiralling flow structure is created. As we know from the aerodynamicists use of vortices to shape and alter flow over other areas of the car, vortices are extremely high energy structures. But with them comes a lot of drag. These wing tip vortices rise upward and outward from the rear wing tips and eventually flatten out behind the car as their energy is dissipated in the free stream flow around the car.
The greater the pressure differential, the greater the vortex created, and this is generally seen better in damp conditions as the water in the air concentrates into the vortex to become visible as a vapour trail.

In years gone by, the site of vortices spiralling from wing tips was seen as a good thing, as the belief that the wing is working hard. To some extent this was correct, with a simple wing the fact that it can create visible vortices did prove the wing was highly loaded. However the drag that it created was less well understood. Since the early 2000’s teams have sought to reduce this pressure difference at the wing tip, in order to reduce drag. Several solutions have been tried to alleviate the pressure differences at the wingtip.

As F1 rear wing have such small aspect ratio’s, (width versus length), there’s little that can be done to reduce this high pressure created towards the endplate without sacrificing total downforce created by the wing. Teams have experimented with twisted wing profiles, reducing the angle of attack of the wing cross section nearer the endplate, to reduce the high pressure created above the flap. But this in turn reduces the downforce created by that section of wing. At tracks where lower downforce is required, teams will still ease the loading of the outer part of the wing, centering the pressure distribution in the middle of the wing.

The other option is to allow the whole span of the wing to be aggressively steep, but use other methods to reduce the pressure difference at the wing tip. Firstly teams such as BAR created a cut-out in the end plate ahead of the flap, this allowed some of the high pressure above the flap to bleed off outside the flap, negating the pressure difference and therefore the strength of the vortex. But this was a fairly blunt solution, so teams created the now-common louvers in the endplate.

This solution directs some of the high pressure air above the wing to the wing tip in a more elegant way. Renault, then latterly Honda and McLaren created a different approach by merging the flap into the endplate, this creates a small gap to direct the high pressure flow to the wing tip.

In the past two seasons reducing this effect has been negated somewhat by other means to reduce the rear wings drag. In 2010 the F-duct allowed the driver to reduce the rear wing downforce and therefore drag. In wet races in 2010 we saw the McLaren’s exit a turn, as speed built up the vortices would appear, then as the driver closed the cockpit control duct the rear wing stalled downforce\drag was instantly reduced. As the driver did this, the vortices also disappeared. This allowed us to see just how soon the F-duct was engaged out of turns.
With the F-duct banned and DRS allowed for 2011, teams are able to adjust the rear wing in qualifying and for overtaking in the race. Depending on the teams qualifying\race strategy, they have redesigned their rear wing to have a different flap size. A small flap, means that the DRS effect is larger, more downforce and drag are shed for more top speed. However the smaller flap means that the rear wing is limited in the downforce it can create, as the sot gap is further back on the wing and separation is likely with aggressive angles of attack. Most teams have followed a design path that errs on this level of DRS effect. As the wing tip is not loaded so highly, there are few vapour trails created.
McLaren however have been almost alone in creating a DRS wing with a large flap, this creates the opposite characteristics of a small flap wing. Less DRS effect is created, but the wing can create a larger amount of downforce when DRS is not activated. Thus their rear wing is steeper and more heavily loaded at the wing tips.

Its for this reason that McLaren tend to be the team in 2011 that create the vapour trails on damp days. McLaren do however have a small flap DRS wing in development. We can expect this to create less trails than their current if it gets to be run in the damp.

 

Book Review: Haynes Red Bull Racing F1 Car

When Red Bull Racing launched their new car for 2011, the event was marked by a very special press pack. The pack was formatted in the style of the well-known Haynes maintenance manuals (PDF). This in itself this was a great book, but almost unnoticed within its pages was the intended publishing of a complete Haynes style workshop manual on the RB6 car.
Now some six months later the Haynes Red Bull Racing F1 Car Owners Workshop Manual (RB6 2010) has been published. As its rare a Technical F1 book is published, not least one with insight into such a current car, I’ve decided to review the book in detail.

Summary
At 180 pages long the book has enough space to cover quite a wide range of topics and it does so. Starting with a background to the team, moving on to the cars technology, to overviews of its design and operation. With its familiar graphical style and hardback format it certainly gives the feel of a proper workshop manual. However this is somewhat skin deep and the pages within, soon revert to a more typical book on F1, although some flashes of the Haynes style do remain.

Steve Rendle is credited as the writer of the book and Red Bull Racing themselves have allowed close up photography of the car and its parts, as well as providing a lot of CAD images.
But clearly a lot of editing has been carried out by Red Bull Racing and the book falls short of its presentation as a manual for the RB6. Despite its confusing title, the book is probably better described as a summary of contemporary F1 technology from the past 3 years.
As the last in depth technical F1 book was the heavy weight title from Peter Wright showcasing Ferraris F1 technology from 2000, this remains a useful source of recent F1 technology.
This places the books target audience, somewhere between the complete novice and those already of a more technical mindset.

Anatomy

With forewords by Christian Horner and Adrian Newey, the opening 21 pages are a background to the team and detail of the 2010 season that brought RBR the championships. Then starts the core 100 page chapter on the cars anatomy, which opens with a pseudo cutaway of the car showing a CAD rendering of its internals.

Firstly the monocoques design and manufacture is covered, with images of the tubs moulds being laid up and CAD images of the RB4 (2008) chassis and its fuel tank location. Although little is made of the fuel tank design.
Moving on to aerodynamics, the text takes a simplistic approach to explaining aero, but there is an interesting illustration of the cars downforce distribution front to rear. This does highlight the downforce created by the wings and diffuser, but also the kick in downforce at the leading edge of the floor, but this is not adequately explained in the text. Mention is made of the front wing and the flexing that RBR deny, this is explained with a simple illustration showing the deflection test. The driver adjustable front flap, which was legal during 2009-2010 seasons, is explained, in particular that the wing was hydraulically actuated. When I understood that in 2009, only Toyota used a hydraulic mechanism over the electric motor system used by all other teams. In trying to explain the nose cone, the text and an illustration show a high nose and low nose configuration, but does not remark why one is beneficial over the other.

This section also covers very brief summaries of bargeboards, sidepods and the floor. Some nice close up photos of these parts included, but again with little explanation. An illustration at this point highlights the other FIA deflection test altered in 2010, which was aimed at Red Bulls alleged flexing T-Tray splitter. In this section the text cites Ferraris sprung floor of 2007, but not the allegation that RBR’s was flexing in 2010. A further simple graphic illustrates the venturi effect of the floor and diffuser, and then the text goes into simple explanations of both the double diffuser and the exhaust blown diffuser.
Having been one of the technical innovations of 2010 and since banned, the book is able to cover the F-Duct is some detail. A complete CAD render of the ducting is provided on page 53; this shows an additional inlet to the drivers control duct that was never visible on the car. This extra duct served the same function as the nose mounted scoop on the McLaren that introduced the F-Duct to F1.
Thus with aerodynamics covered in some 23 pages, the text moves onto suspension and the expectation of detail on the RB5-6’s trademark pullrod rear suspension. After a summary of the purpose of an F1 cars suspension, Pages 58-59 have some fantastic CAD renderings of front suspension, uprights and hub layouts. However the rear suspension rendering stops short at the pull rod and no rocker, spring, damper layouts are detailed. Hardly a secret item, so lacking this detail is let down for a book announced as an RB6 workshop manual. A lesser point, but also highlighting the censorship of some fairly key technical designs, was the lack of any reference to Inerters (Inertia or J-Dampers), The suspension rendering simply pointing to the inerter and calls it the ‘heave spring’, while naming the actual heave spring damper as simply another ‘damper’. Inerters have been in F1 since 2006, predating Renault’s mass damper. Their design and purpose is well documented and shouldn’t be considered something that needs censoring. It’s also this section that fails to showcase the RB5-6 gearbox case. Instead using a pushrod suspended RB4 (2008) gearbox, albeit one made in carbon fibre.
The steering column, rack and track rods are similarly illustrated with CAD images. This usefully shows the articulation in the column, but little of the hydraulic power assistance mechanism. Page 67 starts the section on brakes, again fantastic CAD images supply the visual reference for the upright, brake caliper and brake duct design. As well as a schematic of the brake pedal, master cylinder and brake line layout of the entire car. A nod to more typical Haynes manuals shows the removal of the brake caliper and measure of the Carbon disc\pad. A further CAD image shows the brake bias arrangement with both the pivot at the pedal and the ratchet control in the cockpit for the driver to alter bias.
Although not a RBR component the Renault engine is covered in the next Chapter. An overview of the complex engine rules regarding the design and the specification freeze kicks off this section and cites the tolerances and compression ratio for a typical F1 engine. Pneumatic valves, for along time an F1-only technology are explained, but even I failed to understand the schematic illustrating these on page 77. Also covered in the engine section is some more detail on the fuel, oil and cooling systems. With useful specifics, like capacity of the oil system at 4 litres and water coolant at 8 litres. Again some nice CAD images illustrate the radiators within the sidepod. Many sections have a yellow highlighted feature column; this sections feature is on the engine start up procedure, one of the mundane, but rarely talked about processes around an F1 car (other features are on the shark fin and brake wear). As KERS wasn’t used up until 2011, this topic is skipped through with a just a short explanation of the system.

Moving rearward to the transmission system, the old RB4 gearbox makes a reappearance. Again this disappoints, as some quite common F1 technology does not get covered. Page88 shows some close up photos of a gear cluster, but this is not a seamless shift gearbox. In fact seamless shift isn’t mentioned, even though it made its RBR debut in 2008, the year of the gearbox showcased in the book. I know many will highlight that this might be a secret technology. But most teams sport a dual gear selector barrel, each selector looking after alternate gears to provide the rapid shift required to be competitive in F1. So I think this is another technology that could be explained but hasn’t been.
Tyres, Wheel and Wheel nuts get a short section, before the text moves onto electronics. A large part of the electronic system on a current F1 car is now standardised by the Single ECU (SECU) and the peripherals that are designed to support it. So this section is unusually detailed in pointing out the hardware and where it’s fitted to the car. From the tiny battery to the critical SECU itself. Other electronic systems are briefly described from the Radio, drivers drink system to the rain light.
Of critical importance to the modern F1 car are hydraulics, which are detailed on p105. As with the other sections, CAD images and some photos of the items themselves explain the hydraulic system, although there isn’t a complete overview of how it all fits together.
Rounding off the anatomy chapter is the section of safety items and the cockpit. The steering wheel and pedals are well illustrated with CAD drawings and keys to the buttons on the wheel itself and on the switch panel inside the cockpit.

While I have pointed that the hardware shown in the anatomy chapter isn’t necessarily of the RB6, what is on show is obviously genuine and recent RBR. So for those not so familiar with the cars constituent parts, there isn’t a better source of this available in print today. Even web resources will fail to have such a comprehensive breakdown of an F1 car.

The Designers view

Moving away from the Haynes format of a workshop manual, the book then moves into a chapter on the cars design, with comments from Adrian Newey. It details the Design Team structure and some of the key individuals are listed. The text then covers the key design parameters; centre of the gravity and the centre of pressure (downforce). Plus the design solutions used to understand them; CFD, Wind Tunnels and other simulation techniques. Each being briefly covered, before similar short sections on testing and development close this chapter.
Although the text makes reference to creating ‘the package’, something Newey excels at. This section doesn’t provide the insight into the overall design philosophy, which one might have hoped for.

The Race Engineers view
Where as the Designers view chapter was limited, the race Engineers section was a little more insightful into the rarely talked about discipline of getting the car to perform on track. The process of setting up the car is covered; from the understanding of the data, to the set up variables that the race engineer can tune; suspension, aero, ballast, gearing brakes and even engine. Usefully the grand prix weekend is broken down onto the key events from scrutineering, to running the car and the post race debrief. Feature columns in this chapter include; Vettels pre race preparation and the countdown to the race start.

The Drivers view
Ending the book is an interview style chapter on the driver’s time in the car, mainly the driver’s perspective from within the cockpit when driving the car on the limit and the mindset for a qualifying lap. A simplistic telemetry trace of a lap around Silverstone is illustrated, although there is little written to explain the traces (brakes, speed and gear), this is accompanied by Mark Webbers breakdown of a lap around the new Silverstone circuit.

In conclusion
When I first got this book, I was constantly asked if it was worth the purchase or if I’d recommend it. If my review is critical at points, it’s mainly because some technology that could have been covered wasn’t. Or, that the content falls short of the books title suggesting it was a manual for the RB6.
Those points aside, I have learnt things from this book. Like details of the F-duct system, the Front Flap Adjuster and a wealth of smaller facts. There isn’t a better book on the contemporary F1 car. In particular the CAD drawings and close-up photos, just simply aren’t in the public domain. From the pictures we got over the race weekends, we never get to see half the hardware and design work that’s pictured in this book. So I’ll keep this book on hand for reference for several seasons to come.

Overall I’d recommend this book to anyone with a technical interest in F1.

Many thanks to Haynes Publishing who have allowed me to use their Images and PDFs to illustrate this article

This book is available from Haynes

McLaren New DRS Rear Wing

McLaren have followed their own strategy on the DRS rear wing this season. In contrast to other teams McLaren have designed their wing for the best Non-DRS Performance, thus when deployed the DRs provides a more modest boost in speed. This Strategy appears to have been reviewed as their new rear wing tested at Silverstone shows.

Already being one of the fastest cars in a straight-line, McLaren perhaps haven’t needed to exploit DRs as much as other teams. Their current wing sports a large flap which due to its geometry flattens less when DTS is deployed. See DRS Geometry. But we have seen that McLaren can deploy their DRS less on Q-laps and despite their KERS and speed, sometimes struggle to pass other cars. SO their new wing exploits more conventional geometry with a shorter chord flap that flattens out more completed to maximise the drag reduction system.

Along with the shorter flap other aspects of the wings design have changed, the slots on the endplate have been made even more shapely and the endplate merged into the flap. These slots have been a feature on F1 rear wings for nearly ten years. They aim to take some of the high pressure air above the wing and direct it out through the endplate at the wing tip. This reduces the pressure differences that create the vortices at the wing tip, these vortices often seen in damps condition create a large amount of drag, reducing them further aids top speed.

Although the slots are so curved it’s hard to detect, but the sections between these slots on upper part of the endplate are directly joined to the flap, thus the flap is remotely mounted, the loads pass through these three narrow section of endplate. This must be quite a structural feat. This design harks back to McLaren’s 2008-209 wings (see below) which mimicked the Renault practice of merging the endplate into the flap. Again the aim of this design was to manage the pressure differences at the wing tip for reduced drag.