A wide variety of vehicles with different engine and drive concepts meet at the “Dakar”. The contenders are classified by groups, T1 (prototypes like the Volkswagen Race Touareg 3, its competitors from BMW as well as the buggies), T2 (production-based vehicles), T4 (commercial vehicles from 3.5 tons upwards) and US (SCORE/Baja regulations as well as 4WD vehicles above 2.8 tons and less than 2.20 metres width). 16 cubic capacity categories ranging from under 1.6 to above 5.25 litres allocate various basic weights to two- and four-wheel driven cars of the T1 class.
The Race Touareg with a 2.5-litre TDI engine has a minimum weight of 1,787.5 kg. For comparison: The minimum weight of the BMW X3 with a three-litre diesel engine is 1,900 kg. A two-wheel-driven buggy from the cubic capacity class of the Race Touareg is allowed to weigh 1,190 kg. Both diesel and spark ignition engines are permitted.
The diameter of the wheels is limited to 810 mm (4WD) and 940 mm (2WD). Suspension travel for 4WD vehicles with independent suspensions is limited to 250 mm. There are no suspension travel limits for cars with two-wheel drive.
Help by mechanics only at the bivouac
Compliance with the service rules is an important element of the Dakar Rally competition. During the special stages third-party help is prohibited – excepted from this is assistance rendered by other rally participants including, among others, the race truck crews. Volkswagen sends two of them to the race at the 2011 Dakar Rally.
As a general rule, the vehicles may only be worked on at the bivouac. GSM and satellite telephones may be carried aboard the rally vehicle for emergencies, but may not be switched on during the drive.
A new starting order every day
The rally vehicles start to the first leg in the order of their vehicle numbers. On all subsequent days the starting order in the four individual classifications for cars, motorcycles, quads and trucks is determined by the results of the previous special stage.
Consequently, a good stage result may turn into a disadvantage while a poor result may prove to be an advantage. Depending on the overtaking opportunities on the route – which depend on the terrain – this may lead to further time losses. But the starting order may also become a tactical element, for instance, by following the tracks of the preceding vehicles to make navigation easier or to avoid losing time as the first vehicle on the track when the gravel is still loose.
Stringent speed limit
Top speeds during the “Dakar” are largely limited. Service vehicles – depending on the particular country – must adhere to respective speed limits. Service trucks may travel at a maximum of 90 km/h. For racing cars there is no limit, they reach speeds of up to 190 km/h and more. In populated areas a speed limit of 30 or 50 km/h is prescribed for all vehicles and permanently monitored by GPS.
The GPS systems of the supporting crews are randomly checked at the end of the rally. Violations of speed limits are subject to severe penalties – up to and including disqualification.
Strict rules for navigation
Strict rules are also imposed on the navigation of the rally teams. The organiser sets various way points on the legs. In addition to Way Point Masked (WPM, which is only visible during the approach), Way Point Eclipse (WPE, which is visible after the previous way point) and Way Point Visible (WPV), there are control points (Passage Control = PC) plus the beginnings and ends of speed limit zones (DZ and FZ) on the agenda. If participants miss any of these points, which are logged by the onboard GPS module, severe time penalties may be imposed. If a driver/-co-driver duo misses four consecutive way points it may be excluded from the rally.
Safe overtaking due to sentinel system
For all participants in the four “Dakar” categories, i. e. cars, motorcycles, quads and trucks, the so-called sentinel system is prescribed. It warns the crews with an acoustic signal whenever a rival is approaching from behind. If the system is triggered by the crew of a vehicle coming up the team is obligated to let the faster contender overtake.
The objective of the sentinel is to allow safe overtaking manoeuvres and to minimise the risk for the passing vehicle. During the rally, in addition to the sentinel system, the GPS and Iritrack modules for position tracking of the participants must be installed in the vehicles and functional during the drive. Safety aspects in case of an accident are crucial in this regard as well.
Time zone is a travelling companion
Throughout the Dakar Rally the same time zone applies – irrespective of the actual local time. The reason why there are no changes made to the respective local times is that control of the prescribed maximum times during the liaison stages of the driver/-co-driver pairings is easier this way.