«The Club Arnage Guide to the 24 hours of Le Mans 2015 Every input was pure reflex - things were coming at me everywhere I looked. For about 50 ...»
Changes to 2015 focus on the Porsche Curves. This iconic series of fast sweeping bends were introduced in 1972 and are considered by drivers one of the most challenging aspects of the circuit. The changes start on the outside of the tricky right hander that leads the cars into the complex and are not to the tarmac itself but consist of extended run-off and gravel trap. To accommodate these changes the banking has been moved backwards. New NASCAR style ‘Safer’ Tec Pro barriers have been introduced in an effort to improve safely.
23The Club Arnage Guide to the 24 hours of Le Mans 2015Major circuit changes - overview
1923 – 1928 10.726 miles, initial track 1929 - 1931 10.153 miles, hairpin bend at Pontlieu cut out 1932 - 1955 8.475 miles, new section from the pits to the Esses and Tertre Rouge 1956 - 1967 8.364 miles, wider pit straight, Dunlop curve changed 1968 - 1971 8.369 miles, Ford chicane installed 1972 - 1978 8.475 miles, new Porsche curves between Arnage and the Ford chicane 1979 - 1985 8.467 miles, modified Tertre Rouge corner 1986 8.51 miles, modified Mulsanne corner 1987 - 1989 8.41 miles, Dunlop chicane installed 1990 - 2001 8.45 miles, Mulsanne chicanes installed 2002 - 2006 8.483 miles, new section between Dunlop Bridge and Tertre Rouge 2007 8.480 miles, Tertre Rouge was modified The current track layout
LMP1 - Le Mans Prototypes Class 1: A new era - It’s all about the energy consumed For many years, in order to prevent excessive power development, the rule makers for Le Mans and almost every other motor race on the planet have restricted engine output by limiting the cubic capacity or the number of cylinders, by modifying the size of air restrictors or restricting turbo boost, thus limiting the amount of air (and thus fuel) which could be fed into the engine. From 2014 in the LMP1 category, these fundamentals radically changed in that the energy consumption of the engine becomes the key factor. Manufacturers can largely build what they want.
There are minimal restrictions on engine size number and turbo boost and in addition the regulations permit up to two energy recovery systems (ERS) per car. These systems recover what would otherwise have been lost energy and allow it to be used to power the car. However, what the regulations have done is give with one hand and take away with the other. Depending on the level of energy that a car can recover and use, it is placed into a category that determines how much fuel it is allowed to consume. Fuel flow meters measure the flow and relay the information back to the authorities. In simple terms, the new regulations challenges entrants to make the best use of a prescribed amount of energy in order to cover the longest distance within a given time – such as 24 hours at Le Mans. This makes the challenge for the cars to be both fast and energy efficient.
Old hands among the fans remember that this concept is not really brand new: In the glorious days of Group C sports car racing there was a regulation which limited energy consumption, everyone got an allowance of 2,140 litres of petrol for the whole of the 24h of Le Mans. Engine constructors had complete freedom, in those days Porsche raced a 6 cyl. flat 3.0 litre Turbo, Jaguar used 7.0 litre V12 normally-aspirated engines, the folks at Mercedes built a 5.0 Litre V8 Turbo and Mazda used a rotary engine. Despite these very different concepts the performance of the competitors was close to each other, competition was fierce and the races were interesting to watch. However, in the Group C days there were no energy recovery systems around and diesel was only used for team trucks, so this rather simple approach worked fine.
For 2015, the differences between manufacturers and privateers have been abolished, and the class is now divided into LMP1 Hybrid (for cars with ERS) and LMP1 (for those without ERS).
Hybrid systems are prescribed in four different performance classes, and a maximum amount of energy able to be used is defined for each of these classes. The energy chart below shows the amount of energy allocated to each power train concept, and the associated fuel flow allowed.
What this boils down to is that entrants must have optimum control of the car’s fuel consumption, be able to approach the permissible energy limit as closely as possible, and the drivers must exercise an efficient driving style. If the amount of energy available per lap is not fully consumed, it cannot be carried over to subsequent laps and will 25 The Club Arnage Guide to the 24 hours of Le Mans 2015 therefore be lost. Should the prescribed maximum levels be exceeded, the excess consumption must be compensated for within three laps, otherwise penalties like stop-and-go may be imposed. So effectively, the manufacturer with the most efficient power train being driven by drivers with an efficient driving style will win the race.
All this will mean that on-board loggers and computers will constantly be monitoring the fuel flow and output of the energy recovery systems, and data will be sent real-time to ACO computer equipment which will flag any discrepancy to the stewards. What this means is that the teams monitor the car's fuel consumption and if it goes over that allowed in their hybrid category, then the driver is instructed to recover the discrepancy, by for example, slowing down.
Today’s constructors seem to have a very different view on what might be the best solution, so similarly to the old Group C we see a variety of extremely different engines and hybrid systems.
Toyota (6Mj) use a 3.4 ltr. V8 normally aspirated petrol engine driving the rear wheels together with a hybrid system using energy recovery from the front axle, energy storage in a supercapacitor and drive electric motors on the rear axle.
Audi (4Mj category) employ a 3.7 ltr. V6-Turbo Diesel together with a hybrid system recovering energy from the front axle together with 700kj accumulator storage driving electric motors on the front axle.
Porsche (8Mj) have the smallest engine with a 2.0 Ltr. 4-cyl-Turbo petrol engine driving the rear axle in addition to a hybrid system recovering front axle and exhaust energy, storage using a lithium iron battery and drive electric motors on the front axle.
Nissan (2Mj), who return in 2015 with a very innovative design including a (Panoz inspired???) front-engine 3 ltr V6 twin turbo driving the front wheels in addition to a flywheel energy storage that can mechanically power both or either the front and rear axles.
The ACO, in their perennial quest to have all cars in a given category going round the circuit with exactly the same lap times (fortunately they have not yet achieved this!!), have defined the principle of “Equivalence of Technology”, and this gives them the ability to balance out the performance between the hybrids and non-hybrids by increasing the performance of the non-hybrids. This EoT is calculated on historical data collected from the fastest car(s) in each technology.
Manufactures must balance all the compromises in their design – the conventional fuel driveline together with the hybrid components including the systems to recover the energy, the storage, and the hybrid drive method and the overall impact these have on the car’s weight as well as packaging and reliability. Conventional wisdom appears to suggest that the more hybrid capability a car has, the faster it is, despite the best intentions of the regulations. In addition, the more efficient the car is, the less refuelling it has to have, so the longer it can stay out on track.
Other Changes in LMP
In LMP1 (hybrid and non-hybrid):
The rules essentially remain unchanged for 2015, allowing competitors to continue racing their existing chassis, however cars conforming to the 2014 specification can also be entered. Open prototypes are still allowed in this class and manufacturers are discouraged – “The ACO do not wish to encourage the Manufacturers to invest in LMP2 in any developments which improve the performance of the cars. The main objectives for these cars must be reliability, safety and a low maintenance cost.” Also the rules for the LMP2 engines remain unchanged, and for cost reasons, these need to be based on production engines.
Once again, the balance of performance between different cars can be adjusted - in other words, if your car performs consistently better than others in the class, your car will be slowed down by reducing engine power, having additional ballast or by reducing fuel tank size.
One of the timed laps in qualifying MUST be made by a silver or bronze driver
The GT cars
For 2015, there are no significant changes to the regulations. These are cars built by manufacturers for sale on the open market: Engine sizes are limited to 5.5 litres for normally aspirated engines, and 4.0 litres for turbos. Fuel capacity is limited to 90 litres. These cars are based almost totally on the old GT2 specification, with a few minor changes (ie paddle shift systems allowed and display, push buttons and switches allowed on the steering wheel).
Cars not homologated by a manufacturer will also be accepted if entered by tuners - subject to separate homologation criteria. All cars are limited to one evolution per year, to be made before the first race of the season.
LMGTE is sub-divided into two separate classes:
LMGTE-Pro - designed more especially for professionals where up-to-date models are used as the basis for the race car. Driver line-up is free.
LMGTE-Am - more for the 'amateur', where cars must be at least one year old and without further modification. This is designed to create a second-user market for GT cars. The crew is limited to only one professional driver. One minor change in 2015 is that one of the timed laps in qualifying must be made by a bronze driver.
Leader Lights In 2007 the A.C.O. introduced the “leader lights” system. Each car must have 3 LED lights mounted on both sides;
these lights have different colors for each class:
The leading car of each class will show one light switched on, the second place car two lights, the third place car 3 lights; if no lights are burning then the car is fourth or further down the order. These “Leader Lights” will help trackside spectators to follow the progress of the race, especially at night or in poor visibility. This system reloads at the timing line so it is basically the previous lap position that one is viewing.
27The Club Arnage Guide to the 24 hours of Le Mans 2015The 4 classes – overview
The following overview page gives just the most basic facts; the exact regulations are very extensive with lots of technical stuff, e.g. numbers about the minimum of road cars produced for the GT classes, size of the wings and others. All figures mentioned are maximum values, except the car’s weight of course…
The full regulations (see www.24h-lemans.com) cover everything from what can be done where and when, the penalties for infringement, to what patches must be worn by drivers and mechanics on their worksuits. These rules now cover all races in the WEC Championship, with differences for Le Mans. Although the regulations look rather comprehensive and strict, the organizers often leave themselves the option to decide differently because of “force majeure”, a term which can be found many times in the sporting regulations. The following list is just a summary of some of the rules.
Race Numbers All race numbers displayed on the car (side and front) must be in the ‘class’ colours ie LMP1 – red, LMP2 – blue, GTE-PRO – green and GTE-AM – orange. The actual numbers are in white on a background of these colours. They must also be lit so that they are visible in the dark.
In-car Cameras All competitors have to accept and facilitate the setting up in their cars of a system of technical means enabling the production, the storing, the selection, the compression and the transmission of a video signal or any other signal via satellite.
Any other camera can only be used on the test day and the free practice session on Wednesday.
Drivers Drivers are placed into one of 4 categories - Platinum, Gold, Silver and Bronze depending on their experience and ability. See separate section in this guide for details To be accepted, a driver must be on the ACOs list of confirmed drivers. If they are not, they can a)take part in the Test Day or b)take an ACO-organized half-day training course to gain a certificate of competence.
A maximum of 3 drivers is allowed for each car. Drivers are not allowed to change to another car during the race, even within the same team In order to qualify, each driver must achieve a lap time at least equal to 120% of the average of the 3 best laps set by 3 cars of different makes, and at least equal to 110% of the best time achieved by the fastest car in each of the classes LMP1, LMP2 and GTE Pro. In GTE AM, the CAR must meet these criteria - ie any and only one of the drivers need to meet them. Furthermore, all drivers have to do a minimum of 5 laps during night time qualifying sessions, at least one of which must be a complete lap (ie must cross start/finish line).
A driver is only allowed to drive a maximum of 4 hours within a 6 hours’ time frame (minus pit stop time) Maximum total drive time for a driver is 14 hours Minimum drive time - For LM P2 and GTE Am categories, a driver is not permitted to drive less than 4 hours New in 2015 – Tyres
There is a limit on the number of dry-weather tires that can be used during race week:
Test day The Test Day is mandatory for new Cars, new Teams and new Drivers.
In 2015, the new LMP3 cars will be allowed at the test day, but are not allowed in the race.