BACKMulsanne's Corner NEWS
March/April 2009
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All news content copyright Michael J. Fuller, unless otherwise noted


Audi R15, Sebring 20094.9.09, updated 4.14.09

>>It's with some irony we post this link to an article on Autosport regarding rival teams questioning the legality of the Audi R15.  Summarized, the article indicates that both Aston Martin Racing and Peugeot have begun to question the legality of design details on the Audi R15.  

As written, the challenge posed
seems to indicate a general lack of understanding of the regulations as they are written, namely this paragraph from the article:

The LMP1 regulations state that "with the exception of the rear wing... no bodywork or underbody element having a wing profile is permitted". Audi's rival believe that the splitter element contravenes this regulation.

Careful reading of the LMP regulations will lead one to Article 3.6.1 (Aerodynamic devices) and the symmetrical "wing" exemptions within that Article (frequent readers to Mulsanne's Corner will be very familiar with Art 3.6.1).  And there is pretty clear evidence that the main plane and flap on the R15 are of symmetrical profiles and thus governed by those bullet points.  Ultimately the Audi R15's design execution, post-2007 3.6.1 clarification, was the inevitable direction, wasn't it?  
To protest 3.6.1 now, well, isn't it a bit too late (consider the Porsche RS Spyder's valance panels)?  At this point it seems the Audi has simply out-drawn its rivals.

Lola B05/40Looking at the details of the complaint as laid out in the Autosport article, the front wing has been called out (as mentioned above), but so too has the coke-bottle duct/channel at the rear of the car.  According to Aston Martin's 
George Howard-Chappell , "The question is what constitutes an aerodynamic opening and what constitutes a radiator duct?"  It's very interesting to note that this detail has been on every Lola (with the exception of the LMP1 Lola) since the B2K/40 (B05/40 at left):

B05/40 LMP2 Series

So this interpretation is nothing new for sure, precedent has been set, and for quite some time.  Having seen the Audi execution first hand I really couldn't say it was any different than the Lola's.  And while historically the regulations always had wording limiting "ducts to no where", here's the text from the 2001 ACO LMP900 regulations, Art 3.4.5 a/:

The air intakes the purpose of which is to feed the engine, cool mechanical components (radiators, brakes, gearbox, etc.), and to provide ventilation for the driver and engine compartment shall not induce aerodynamic effects;

...the wording, "
shall not induce aerodynamic effects," fell out years ago (with the 2004 LMP1/2 introduction) as the cars became more intricate and what instituted "aerodynamic effect" anyway?  A conventional radiator intake induces such an effect; the regulations never stated "positive" aerodynamic effect...  So without that wording within the current rules, it becomes difficult to point a finger at any opening whose clear purpose was aerodynamic.  And then the waters certainly get cloudy if you innocently place your brake cooling ducts in such a channel (as on the Audi...and the Lola).  Then you get into arguments about the primary purpose of the intake, yada, yada, yada, it becomes endless.  So in a sense it's good that the terminology is gone from the regulations as that then eliminates a lot of the contention about ducts/channels within the bodywork.  And as long as they meet the bodywork regulations, then they are legal, right?Audi R15

But even with all of this, one only needs to take a look at the Lola Aston Martin to find cloudy areas as well.  Purusing over to Art 3.4.5 that governs air intakes, and then scrolling down to section d.2 concerning closed top cars:

d.2 - (Air intakes must...) Be integrated into the curved line of the roof.

Even the briefest of glances at the Lola Aston and it is clear the roof mounted engine intake is of questionable nature in that it doesn't integrate to the profile of the roof; it is a separate surface and shape and is offset (though connected to) from the roof line.  Basically it all hinges on the word "integrated" and comes down to interpretation.  Perhaps the point is that there are potential contentions on every car?

So is there a fight brewing?  The ACO was noncommittal when asked if they would request Audi to make changes to the car should, upon reexamination, details be deemed, well I don't know what, "illegal" I guess (Audi responded saying that as the car had been homologated they weren't changing jack).  Interestingly, at Sebring Audi's Wolfgang Appel confirmed that the ACO did request changes to the design to be made to the R15 prior to its homologation being accepted (see our 3.13.09 news segment).  So the ACO has already tread this path with Audi and scrutinized the car's design and found elements that they weren't in favor of.  If they had any further questions, wouldn't that have been the appropriate time to address them?  Yes, you'd like to think so and you can bet everything was brought onto the carpet then and there.  As we're constantly dealing with the word "interpretation", you'd like to think once the ACO signed off on a design, that was that; precedent was therefore set (see Lola engine intake for an example).  They are, after all, the dictator of the regulations.

The ACO says they will soon issue a rules clarification.  But will that mean Audi has to make changes to their car, i.e., which side of the decision will Audi fall?  We shall see.

Considering that images of the car are now readily available, we're reposting the Pescarolo shots.

>>Bernard Fournier has been gracious enough to share these images of the updated 2009 Pescarolo.  We see the familiar shape but with some new and interesting details.  The bodywork between the fenders and the nose comes further forward than on previous Pescarolo LMPs and ends just shy of the leading edge of the splitter.
The outer edge of the splitter takes on a shape familar to the Acura ARX-01a/b.  The vertical endplate, just inboard of the outer edge of the splitter this year, is a familiar Pescarolo item.
The deep sculpting of the side pod is evident.  Legality louvers sticth the sidepod to the trailing edge of the front fender.  Note the vent on the inboard face of the front fender pontton.
The arrowed item is of interest.  Clearly it seems to be oriented to produce downforce, but is it also being used as a radiator exhaust chimney given the slots in the outboard edge?  

There's discussions from Barcelona that items on the car have been deemed non-compliant with the attention being drawn to the chimneys here.  Endurance-Info has published an image that shows the chimney having been removed.

Audi has released an image of the livery of Team Kolles Audi R10 set to race this year in the Le Mans Endurance Series and at Le Mans.  Worthy of note is the rear wing.  It would appear to effectively be the R15's wing assembly but for different endplates and possibly mounting pylons (bottom portion).
2009 Audi R10, Team Kolles livery

2009 Audi R10

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Acura ARX-02a, Sebring 20093.29.09

Well another 12 Hours is done and dusted, they say this one was epic.  I’ll leave the color to others because, let’s face it, you don’t come here for that...

>>Following their pole win, Acura seemingly faded from the weekend when they took up shadow position to the two primary race protagonists.  There's already a skeptical drum beat sounding throughout the media and forums that perhaps the Acura program wasn't "ready for prime time."  Certainly the effort is in its literal infancy, especially compared to the very well honed Audi and (somewhat less so) Peugeot effort. But that seems to overlook the obvious. So neither car finished due to various component failures (gearbox on the #9 Highcroft car and suspension failure on the #66 de Ferran car).  It is our understanding that this issue came down to "poor lifing control" of the components in question.  The positive here is that there's an obvious solution to that issue and we can imagine it's in place as we speak. Looking at their on track performance, in the race the Acuras appeared to be about 2 seconds off the absolute race speed of either the Audi or the Peugeot, take your pick. And while on a single lap, or a string of laps, the Acura can keep pace with the front runners (see qualifying), when traffic was brought into the equation the Acura suffered even more so not having back marker dusting uber-torque. Maintaining the car's momentum is paramount to laps times in this car. But in order to merely keep that pace, albeit slowly drifting through race length stints, the Acura drivers had to drive their hearts out and then some. The Acura makes up the power deficit to the diesels through higher cornering speed, which means higher G-loadings on the driver, lap after lap. We understand that the performance deficit to the diesels could be bridged by running even higher downforce levels or custom tires, but the car is currently at, or very near the upper levels of human performance. That is, chances are the drivers simply would not be able to corner the car at that speed for any given race length. This poses something of a quandary to the regulations makers. If a factory effort takes the page of the regulations that deals with gasoline powered LMPs, designs their car to those regulations, and yet finds itself in effectively the same position as anyone else would be in if they came to the table without a diesel ("knife to a gunfight" as one has described it even now in light of the changes the ACO has made to diesel regulations for this season), what then?
Peugeot 908, Sebring 2009>>Peugeot had a bit of a scare when it was discovered Tuesday evening, during a routine inspection, that a previously repaired section of the monocoque had begun to crack again.  The damage was located at the front of the tub in the critical area of the suspension pickup points.  Discussions surrounded how to solve the problem; repair the tub on site or fly in a new one from France by Friday with the result of having to skip qualifying and start from the back of the grid.  But in order to initiate the repair Peugeot needed a critical repair jig manufactured.  This is where Dennis Spencer’s Fabworks steps in.  Fabworks put their Buford, Georgia facility at Peugeot’s disposal and by 1:45 pm on Wednesday CAD drawings and photos had been transferred and work commenced on the part.  Peugeot was then able to virtually look over the shoulder of Fabworks' CNC operator, as their part was cranked out, using Fabworks’ IP camera.  In the mean time, Spencer moved one of his airplanes from the Atlanta area to the Gainesville airport (15 minutes from the Buford shop) in anticipation of flying the item directly to Sebring International Airport.  And at 5:13 pm, the plane lifted off and headed south.  Everyone involved was then able to track the plane’s progress through Flight Aware.  Touchdown occurred 2 hours and 43 minutes later and the repair jig was handed off directly to Peugeot at the airport.  Peugeot declared the jig perfect and initiated the repair finally finishing up at 3 am Thursday morning and in time for the after noon qualifying session.

>>We understand the Peugeots routinely ran through the tech line posting weights a good deal above the 900 kgs minimum.  Peugeot has admitted that they have stopped development on the 908, instead concentrating on the 909 HY.  But given the obvious pace of the 908 in spite the cessation of development coupled with it not even being at fighting weight, a couple of things come to mind.  Clearly the car is all engine.  Sure, the aero is competent, but you really have to think Peugeot has put most of their concentration on engine side and in getting that power to the track.  Another thought also creeps into the picture.  How fast was Audi really trying to go?  I have suspicions that Audi didn’t even come close to showing their entire hand and thus the Peugeot was closer than it would have been.  It is a three year old design after all, frankly it wouldn’t have much business being quicker than the R15, would it?
>>Speaking of weight and late nights, it is our understanding the Acura ARX-02 is designed to be several hundred pounds under the minimum weight in order to be ballasted to the minimum of 900 kgs.  This is done primarily through a several inches thick piece of steel or similar thick and heavy metallic ballast located on or near the front wheel centerline.  We also hear the Acura teams had a number of late nights, some of this is due the car's less than user friendliness: 6-7 hours for an engine swap and 2 hours for a power steering change.  

>>The #16 Dyson Lola-Mazda had a bit of a fright when the wing departed rather unceremoniously during the race.  The #16 continued on to the pits and the wing landed between turns 3 and 4 where it stayed until being retrieved later in the race, perfectly intact.  According to Lola’s Julian Cope, upon inspection, it appeared the failure was related to rubber build up causing a vibration that simply rattled the wing loose.  Ultimately the wing's bolt through holes were undamaged and the threads in the pylons intact.

>>There are still persistent thoughts within the ALMS paddock that the ACO regulations are not equitable between diesels and gas powered LMPs.  I suspect you’ll hear the chorus of “sour grapes” about now, but lets get everything on the table here and now—there are still talks of being upwards of a 100 hp deficit between the top gasoline powered cars and the diesels, this even after the ACO’s 10% restrictor diameter decrease for diesels.  So we're not talking small reachable-thorugh-development offsets. With Henri Pescarolo having been appeased by Peugeot, who then takes up the challenge to the ACO regarding the regulations?

>>And the biggest waste of money?  It has to be the ACO’s rear wing regulations.  For all the cost and effort, the rear wing regulations changes have effectively resulted in cars that are as fast as last year (once the track was rubbered in we saw true speeds—qualifying wasn’t representative of what the cars are capable of given the support series action and the rubber put down by them).  We’ll suggest that a much cheaper alternative would have been a simple large inlet restrictor cut across the board aimed at 100+ hp.  Sure, there would have then been the temptation to optimize the package to that restrictor and thus regain performance, but at that point costs would be optional.  What’s the ’09 rear wing update package cost (mandatory mind you), $50,000-$100,000?  For about $1000 the ACO could have actually achieved the desired effect with an across the board power reduction.
Audi R15, Sebring 20093.17.09

>>Mike Callahan, of the ALMS spotter's guide, gives us a first look at the R15's front end.  We can see horizontally mounted torsion bars and the electronic power steering unit.  Front suspension members are individually shrouded as they are at the rear (see Pruett image below).  Brake ducting is as on the R10 in that it's via upright mounted backing plates with ducts mounted to the backing plates.
Audi R15, Sebring 2009Here's a look underneath the R15's front diffuser.  What I've cropped and focused on here is the trailing edge of the flap.  We can see that it comes to a point.  

The rhetorical
question, ultimately, is how has this been deemed legal?  Let's refresh our memory of Art 3.6.1, this is the full text:

3.6.1 - With the exception of the rear wing defined in article 3.6.3, no bodywork or underbody element having a wing profile (*) is permitted :

(*) "Wing profile" : section generated by two arcs with different curves and/or centres joining a leading edge at the front to a trailing edge at the rear, the purpose being to exert an aerodynamic effect, lift or down force.

Are not considered as a wing profiles, the bodywork elements that:

•have a constant thickness,
• have an absolutely symmetrical profile,
• are vertical.

Audi R15, Sebring 2009With that in mind, we can only surmise one thing:  the Audi's splitter wings must be of the symmetrical variety.  Run in ground effect and at an angle of attack, symmetric wing profiles are rather efficient generators of downforce.  Sure, they'd be better served with purpose racing wing profiles,  but you go with what you can.  The recent addition (2007) of the wording,"have an absolute symmetrical profile," to Art 3.6.1 certainly benefits the Audi's designers in this case.  Ultimately it's no secret the main desire is to create a wing in this area as that's the most efficient shape.  Audi has merely taken advantage of what's on the rule book.  It was our opinion back two years ago that the revisions to Art 3.6.1 came about after discussions the ACO had in regards to the updated '07 Porsche RS Spyder.  With the liberalization of the regulations in regards to what was allowed as a "non-wing", the ACO opened the flood gates to all sorts of new and interesting wing interpretations.  
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Audi R15, Sebring 2009>>Festivities are kicking off today at Sebring and SpeedTV's Marshall Pruett is already out of the box with a gallery of images of the Audi R15.

The R15 has shown to be very quick out of the box setting the fastest times (
1:43.596 ) in today's test session.  At that rate the track record looks sure to be broken, and this with less downforce and power than last year.  Well, at least that was the supposed goal of the 2009 regulations.  
Audi R15, Sebring 2009There's little doubt the concept behind the R15's front diffuser is that of a formula car with a mainplane and flap.  It's our understanding the flap isn't adjustable as that would require homologation of each adjusted position.  We're also wondering what the cross section of the mainplane and flap are like as the LMP regulations strictly regulate wings and their location.
Audi R15, Sebring 2009The R15's rear suspension appears somewhat similar in general layout to the R10's.  We can see the (now) near vertical torsion bars (1) as well as the through-shaft "3rd-spring" damper on top (2).  All the rear suspension members are covered in carbon fiber shrouds.  The duct ahead of the rear wheel draws air into this area of the car and out the back to reduce base drag.  The shrouded suspension members helps to streamline the air's route through the duct.  It also appears that the sides of the gearbox are shrouded as well.
Audi R15, Sebring 2009On the Ferrari F2008 F1 car a similar vent appeared.  It's important to note that given the location of the vent on the Ferrari F1 car, the vent was working in conjunction with the front wing and the airflow that shed off the trailing edge.  On the R15, the vent is far enough forward to not to appear to have any interaction with the flap and thus is working aerodynamically on its own.

Go to to see Pruett's full gallery.



Audi R15>>Audi is simply bombarding us with images.  Today they released yet another series of images, these containing the first views of the rear end of the car.  
Audi R15
What's interesting to note here is that the R15 has clearly undergone an extensive revision to the rear bodywork since the first images were released.  

Audi R15
Audi R15From the top we can better see the continuos, unbroken surface that now covers the rear suspension and how it differs from the test car.  It is our understanding that the ACO had something to do with the modification to the bodywork.
Audi R15Unusually, the front fender trailing edge transitions to a endplate which channels the airlflow exiting out of the front diffuser area around the radiators (area defined by the carbon louvers) and down the side of the car.  Traditionally this airflow exits the car just aft of the front fender

Porsche RS Spyder in 2009 ACO aero specification>>The Paul Ricard Le Mans Series test is ongoing and Hidenori Suzuki of the Japanese based website Sportscar-Racing sends us these shots of the 2009 aero kit for the Porsche RS Spyder.  It has been reported that Team Essex is not running the direct injection Porsche RS Spyder engine at the test.

Porsche RS Spyder in 2009 aero specificationWe believe this is the 2008 Le Mans valence panel (as opposed to developed specifically for the '09 aero regulations).  Compare to the "high downforce" version.
Lola Aston Martin, Paul Ricard LMS test 2009Aston Martin unveiled their massaged Lola chassis at the Paul Ricard test.  Essentially Aston has tweaked the car here and there, but the Lola core certainly is evident.  The side pod now connects directly to the front fender instead of being "stitched" together through a valence panel as on both the Lola LMP1 and LMP2 coupes and open toppers.  The entire nose has been redesigned to impart Aston Martin styling hints and thus the brake ducts are now either side of centerline and framed by the traditional Aston Martin "grill" shape.
Lola Aston Martin, Paul Ricard LMS test 2009The rear end has also been detailed with the rear bodywork varying slightly over the standard 2009 Lola update.  The rear wing endplate also seems to be unique to the Lola Aston.

Earlier in the week the car's naming rights became an issue when Prodrive's David Richards was quoted as saying the Lola Aston Martin was a "radical redesign," in one stroke diminishing Lola's involvement in the car's design (original concept and ongoing with Aston).  Lola issued a statement pointing out, "Lola has spent over two and a half years in the research and development of this state of the art car costing several millions of pounds."  Ultimately the release from Lola hit upon the real reason for Lola's forceful words..."When Aston first mooted rehomologation of the Lola car and was given the cost of their contribution to IPR and R&D the negotiations broke down. It is completely inappropriate that Aston Martin should now attempt to achieve 'ownership' through misrepresentation in the media."  In summation, if you don't want to pay for rehomologation then don't go around hinting it's an Aston Martin anyway...

Thomas Enge did the unthinkable and, according to an interview with David Richards on Autosport, promptly wrote the #007 car off on the first day of testing at Paul Ricard.

Images provided courtesy Julie Sueur from Endurnace-info.
Audi R15>>Audi chose to release detailed images of the Audi R15 LMP1 today.  Perhpas they felt left out of all the action at Paul Ricard?
Audi R15The R15's engine is a 5.5 liter turbo diesel V10 that is, according to Audi, rated at better than 600 hp and more than 775 lb-ft of torque.  With two fewer cylinder, the R15's engine is naturally shorter than the R10's V12 engine.  But in addition to that, Audi has been previously quoted as stating that this new TDI powerplant is lighter for the same swept volume.  All of this works towards improving weight distribution, one of the weaker areas of the R10.

And as further evidence of the weight distribution optimization, Audi has announced that the on-board car battery is a Lithium-ion type similar to what is found in hybrid gas-electric road cars.  The use here is for weight savings benefits with Lithium-ion batteries weighing less than the standard lead-acid variety.
Audi R15Preliminary dimensioning shows a very long wheelbase of approximately 3083 mm which is tangentially confirmed by the press release text which states, "Thanks to a longer wheelbase and the optimized vehicle weight the R15 TDI is significantly more agile than its predecessor."  The Audi R10 was on a 2980 mm wheelbase.  The overall length of the Audi R15 appears to be about 30 mm short of the maximum.  Front and rear overhangs are approximately 922 and 624 mm respectively.  For now we can't resolve the apparent 1042 mm height to the top of the rear wing endplate (regulations state max rear wing height is 965 mm).
Audi R15The R15's rear wing is slightly anhederal. Connecting a straight line between the two outer profiles and you can see that center section is raised.  Note the swan necks.
Audi R15The vents in the roof of the nose helps the wide nose pay for its ride.  The wide nose is related to another, for now undisclosed, purpose.
Audi R15While appearing as though a mechanic has leaned on them, there's little doubt about the deliberate placement of the turbo inlets.
Audi R15One of the more interesting details...what do the ducts feed?  And is this an element related to the "raised rear suspension"?  We think so inamsuch as there wouldn't be a radiator located this far back in the chassis.  In essence we're suspecting that the ducts are simply drawing in air to fill in the base area at the rear of the car in order to reduce drag and the rear suspension is perhaps raised and shrouded to augment this.
Audi R15The turbo's exhaust exits out the car just aft of the engine.  This allows for shorter exhaust headers and ultimately less weight.  
Audi R15Some say platypus, we say manta ray...
Audi R15


ęCopyright 2009, Michael J. Fuller