Indianapolis indications - Tech update from the USA
By Craig Scarborough

Introduction
The Indianapolis F1circuit is a paradox, its the newest circuit on the modern F1 calendar but it is neither a new or old new circuit, the circuit is based part on the historic oval circuit and an all new infield section. The F1 circus seems to prefer feeling F1 is new experience to America and Indianapolis is a historic place.
The circuit is another of the contrasting circuits where a tricky slow segment is matched with a fast flat out section separated by a big braking zone. The compromise for set up is aimed much more at the infield section, with the teams running quite high amounts of downforce and hence drag. The infield section is very slow with tight corner leading on another tight corner. It has been termed as “Mickey Mouse” by some drivers, as it lack any challenge to the drivers.
Despite the drag penalty on top speed on the banked Oval section the cars recorded remarkably high top speed especially when the cars are able to get in the slipstream of another car, one of the highest recorded top speeds was J.P. Montoya draughting M. Schumacher in the race. The advantage of the banked start to the oval section is that the banking provides the grip and cars can follow each other more closely with fear of lost downforce from running in a corner in dirty air. The flip side of the high speeds is the load on the engine, this section is the longest single open throttle section of any GP circuit, other tracks have a longer total open throttle time but the are interrupted by chicanes or slower corners. Several teams are trying development specification engines either to test for the 2002 car or for attempting to finish the higher in the championship. Large brake ducts were used for the big stop at the end of the oval section.
The aero and mechanical set up of the cars was similar to Spa where higher downforce triple plane or bi Plane rear wing used. The circuit is unique in that the start finish line crosses a yard long strip of bricks set into the surface. Despite the apparent rough surface of this strip and with the cars passing over at high speed and hence the aero loads pressing the car down nearer the road, No team noted no special set up requirements for it. Jarno Trullis Jordan was subsequently penalised for an over worn plank after the race, Jordan haven’t released telemetry information stating if the bricks were to blame, but they may have contributed to the wear.
Tyres played a big part in the race, the hot temperatures that increased over the weekend worried the tyre manufacturers. The previous GP at Indianapolis last was run before the Bridgestone\Michelin tyre war. The worries over High loading on the tyres on the banked section lead Bridgestone into bringing an overcautiously hard tyre to the race. This year the cautiousness seems to have swung the other way. Ferrari opted for the Harder Bridgestone and still outqualified the other cars on the softer compound. The teams on the softer rubber suffered blistering of the rear tyres and would have hoped for cooler weather for the race, this suggested Ferrari had a trump in their strategy. The Michelin tyres were displaying their usual tendency to perform best after a large number of laps had been completed and performed better in the hot conditions. The race day was indeed hotter but Ferrari suffered with performance from their harder tyres, while the softer Bridgestone runners found the tyres remained durable for a large number of laps despite the heat. This apparent reversal of logic played into the hands of McLaren with their long first stint fuel strategy. The Michelin tyres did indeed come into play after a few laps despite the Williams arriving at the grid on tyres with over 18 laps on them. As the year has developed, the known tyre equation of soft tyre equals better performance over a shorter number of laps and the opposite for harder tyres, is not applying anymore. The choice of the tyre for qualifying and race clearly now comes down to more than compound and other factors like construction and suspension\aero set up play equally large factors.


Up “Periscope”
Recent years has seen teams move away from exhausts blowing into the diffuser to stabilise the car better under different throttle settings. some teams moved them higher up the diffuser which is where they are less effective and hence more stable. Other teams routed them over the sidepods periscope style.

BAR


Prost


Ferrari were the first to try this and found that the faster flow of air accelerated by the exhaust gasses under the lower rear wing element improved the wings performance, while the relatively large distance between the wing and exhaust made the effect more stable under different throttle settings. This could be improved by making the “jet” of exhaust gasses more diffused across the sidepods and onto the wing. This is why the exhaust outlet is set into the sidepod, the “jet” attaches to the flow over the sidepod and flattens to a lower wider shape and is directed under the wing element for best effect. The teams do make a great deal of effort to shape the bodywork around the exhausts. Jaguar have a piece of bodywork\heatshield fastened to the sidepod around the exhaust, that is so close fitting it needs to be removed before the sidepods panels are!



Williams have now run a Periscope set up exhaust system, leaving only McLaren and Minardi not following the “periscope” convention. The new Williams version seems to be utterly conventional, the exits are quite far back and in towards the middle of the car, so it seems nothing innovative has been down with the routing of the pipe work.
Some of the gains with Periscope exhausts is the short and simple pipe lengths possible. With the ever larger bore sizes of the exhausts the complex designs are harder to manufacture. Toyota started the year testing a very long convoluted exhaust system, that directed the primary pipes forward to a collector that then ad the secondary pipe curve back around to point towards the rear of the car, this allowed a tight coke bottle shape to the sidepods and long exhaust lengths, they have now resorted to shorter pipe lengths and still maintained the aero benefits. Also routing the exhausts early up and out of the sidepods leaves less restriction for hot air from the coolers to pass through the rear of the sidepod.

Team by Team

Ferrari
Ferrari has few innovations on the car for Indianapolis some of which were also present in Monza. As reported by Giorgio Piola in Ferrariworld.com The steering wheel featured four new buttons. At least the upper two of these buttons were present in Monza, the buttons were arranged with one pair on the top edge of the wheel operated by the drivers thumbs, jet fighter style, and two at the rear of the wheel.



Their use has not been disclosed, Ferrari use two basic types of button on the steering wheel


A rotary control with indexed settings, these are used for engine, differential, brake map settings
or
a push button for momentarily activating a feature of toggling\scrolling through a control. Such as Radio, pit limiter or dash scroll controls

The new buttons were of the push button type and placed away from instant reach by the driver and from the TV footage were not operated regularly during a lap. Hence are probably not for changing a map or setting of a major system, but for an occasional function for example part of the launch control sequence. Clearly Ferrari are still actively developing their electronics even in this late stage of he season, probably as they can afford to test new systems for 2002 now the championship is over. The basic Ferrari steering wheel has been in use for several seasons now and is running out of space for new controls.

The other possibly new feature was a one piece lower wishbone made in carbon fibre. The lower wishbones has been made in carbon for some time but as separate pieces for the left and right side, the new version moulds them as one piece, this is both simpler and more rigid. The in board ends of the lower wishbone mount on the centre line of the car, hence some overlap is required on the blade like flexures that provide the “pivot” for the wishbone. Making the unit one pieces allows the wishbones to share one larger flexure and less mounting holes to create the gain in rigidity. For a team with two top drivers, during a race week end Wishbones are more likely to be replaced for new geometry settings or for being over their service life than for damage, so the cost impact of wasting a complete pair is minimal.


McLaren
McLaren debuted no now development for the race. Details are emerging from Ilmor the Mercedes engine manufacturer about the direction of the 2002 engine. They have been accused of having been down on power this year after the ban on lightweight low friction beryllium engine internals for 2001 delayed the engines development. Also the V angle of the engine is still around 72 degrees, where as the vogue is already 90 degrees of more. Ilmor have promised a major redesign of the unit for 2002 but are keeping details such as V angle and ancillary layout a secret.


Williams
Williams ran the new Periscope exhaust system on and off during the weekend as well as the new shape sidepods. The new exhaust system removed the exhausts for blowing over the rear diffuser and required a small redesign to shape the roof the outer tunnels in the absence the exhaust pipe. The redesign retained the shaping introduced at Spa.


Another development on the rear of the car was a small rectangular aperture on the rear of deck formed by the sidepods by the side of the rear wheels.
Initially this was thought of as a cooling outlet but closer inspection suggests this is not the case. Like most teams Williams route all the hot air from the coolers out of the rear of the sidepods, there is no longer an outlet on the flank of the sidepod, instead chimneys are used to vent the heat over the top of the sidepod. Seeing as the aperture was not made into the engine area of the sidepods but instead through thin extension to the top surface of the sidepods, it cannot be for cooling.


The next guess is it would be for aero reasons. The first clue is looking at where the hole starts, it sits inline with the flip up, knowing the sidepod is undercut at this point and the downward sweep of the engine cover, my guess is that it is help the flow off the underside of the flip up.
Looking at how the flip up works, there's a clean flow over the flip up, but its the underside that does the work. The underside directs the most of the airflow up over the tyre some of the flow spills off the flip up and flows under deck. this must upset the flow and perhaps slows down the flow in the coke bottle area. Putting the aperture in the deck allows some off this flow to direct up over the deck freeing up the flow under the deck.
This aperture added to the new sidepod shape and the fins leading the sidepod inlets suggest this the flow along the sidepods and over the floor is an area causing Williams problems, as they constantly are seeking improvements.
For 2002 BMW have promised an evolution of the current unit, rather the more radical makeover between the 2000 to the 2001 V10’s.


Jordan
Images of the Jordan with out body work have been rare this year, the team have kept their design secrets quite well. I now have two new graphics describing the cars front suspension and cooler set up.

Cooling



In this graphic the car is actually up on stands having Ballast fastened to the underside of the chassis, so the floor and plank are removed giving us a clear view of the inside of the sidepods.
In the background the shape of the airbox is visible, the airbox splits into three pieces the narrow upper section, and the middle section that widens to form the tray around the actual inlets and fuel injection system. Behind the airbox the damper is just visible above apiece of heat shielding, the damper is operated via a large linkage mounted quite low on the gearbox and the pushrod end sup being quite short and inclined. The exhausts are conventional short length periscope layout.
The Cooling layout starts at the duct at the front of the sidepod, the duct is moulded in one piece and fastened to the side of the chassis. The flow inside the duct feeds upper and lower coolers, the upper cooler is the smaller oil cooler and below that is the large water radiator. The oil cooler is slightly angled to the radiator and may vent via a different route to the flow off the radiator, perhaps ducted up through the chimneys either side of the rear wheels. The piping feeding the coolers is all made from alloy tubing, this is because of the high pressure water system, the links between the sections of pipe are made with QD couplings. The pipes route in front of the coolers, this keeps them away from the heat rejected out the back of the cooler.
One of the other connections on the cooler is the pre warming system, an external fluid heater is attached to the cooling systems which heats and pumps the fluid around the system, this means when the engine is fired up the water and oil are up to temperature and the car can leave the pits and use full revs immediately.
Coming out from under he car and routing through the duct is some electronics cabling. This used to route through the cockpit but is it now more accessible to route under the removable bodywork panel under the nose and up into the footwell. This cabling powers the dash\steering wheel functions, the telemetry from the front suspension and the antenna’s.
The other noticeable feature on the car is the side impact spares, these have been seen before but not as clearly as this. There are four pairs of protection, two on each side. Each pair is made of two hollow carbon fibre spars, the lower pair being thicker and wider. Each pair is bonded and fastened to the monocoque, the very wide monocoque has a recess moulded in to access the upper pair.

Front suspension



The front bulkhead is visible in this shot, In previous updates we’ve seen the rocker linkage son the outer corner of the monocoque, but in this view we can see where the torsion bars protrude from the chassis. It would be expected as with the other teams that the torsion bar is inline with the rocker linkage, but the Jordan torsion bar is well below linkage, this is operated by a drop link for the rocker is aimed lowering the centre gravity. Also the nose continues well ahead of the suspension pickups making the steering rack mounted well inside the monocoque, this must make access difficult especially with only a small access hole in the top of the monocoque. The pick up point for the lower wishbones is visible, this is much wider than most designs and obstructs the airflow off the front wing, in comparison to other designs.
Also the complex front mounted barge boards are clear, they are made form three surfaces, but neatly they are made in one piece. The lower surface runs the full length of the board in a shallow curve away from the car, the front surface curves in much tighter and the smaller rear surface is very curved.


BAR
No obvious developments were tried in the USA. Honda have announced that their 2002 engine will feature a 95 degree bank angle and the packaging the ancillaries would be much neater and lower to provide the designers with more freedom to package the unit.


Arrows
No obvious developments were tried in the USA. The team have signed Sergio Rinland the ex-Sauber designer for 2002, which added their latest spec Cosworth engines should see the team feel confident of progress on 2002.


Prost
No obvious developments were tried in the USA


Minardi
No obvious developments were tried in the USA


Sauber
No obvious developments were tried in the USA


Benetton
No obvious developments were tried in the USA


Jaguar
No obvious developments were tried in the USA