| Touareg takes the high ground |
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As well as passing the tough requirements of international safety legislation, they should also be capable of protecting occupants against the many additional hazards in off-road driving, an area beyond the scope of legislation. In addition, there is also the challenging consideration of pedestrian protection, an area where many off-road vehicles have a poor reputation. Passive or secondary safety As the most recent addition to the 4x4 market, the Volkswagen Touareg is an interesting example of how some of the conflicting issues may be solved in an off-road vehicle. Legislation is mainly concerned with passive safety, which is the protection of occupants in the event of an accident. Here Volkswagen has taken into account the requirements of Euro NCAP and US NCAP and also the FMVSS 208 test, which is mandatory for all vehicles sold in the US from 2003. In addition, Volkswagen has its own internal crash test standards that must also be met. These go beyond the requirements of legislation. Features that help here are very high performance crumple zones at the front and rear of an extremely rigid passenger cell and additional reinforcing bars in the sills. Extremely rigid A, B, C and D pillars are integrated with a similarly rigid framework around windows and door openings, using laser-welded seams. In addition, highly stable door construction provides maximum flank protection in the event of side impact and is also integrated into the vehicle crash protection structure. Isofix attachments, which enable standard child seats to be attached quickly and securely to the vehicle’s structure, are fitted in the rear and a key-operated switch enables the front passenger airbag to be de-activated if a child seat is to be fitted in the front. Even after an impact, safety systems come into operation. As soon as a predetermined crash impact is exceeded or the airbags are triggered, all doors automatically unlock, the battery is isolated from the charging system, the fuel supply and all high-power electrical units, such as the air conditioning, are shut down and the hazard lights are switched on. Occupants are protected by a state-of-the-art electronic safety system, which has early-warning crash sensors. These activate the driver and front-passenger airbags at a level of intensity based on the severity of the accident. The system can choose between two levels of intensity. Standard equipment includes front and side airbags, and curtain airbags that cover the entire window surface between the A and C pillars. The Touareg is also fitted with electrically triggered seatbelt tensioners for occupants in all but the centre-rear seat and force limiters for driver and front passenger. All five seats have three-point automatic belts, and belt-height adjustment is provided for the four outer seats. A warning sounds if the driver does not fasten his or her seatbelt. Pedestrian and cyclist protection The Touareg has been designed, as far as possible, in accordance with the safety needs of the most vulnerable road users: cyclists and pedestrians. Such measures include a deformable, rounded bonnet, made from energy-absorbing aluminium and plastic wing panels. Care has been taken to ensure that no rigid components lie directly behind the relatively forgiving aluminium and plastic panels. Pedestrian-friendly, energy-absorbing zones are thereby formed between the front outer panels and the harder components behind them. The smooth, rounded shape of the Touareg avoids the traditional, aggressive 4x4 design and combines aerodynamic efficiency with better consideration for other road users. Continuing a long-established strategy, Volkswagen refuses to offer so-called “bull bars”. Active or primary safety
As would be expected, anti-lock brakes are standard and four-wheel drive brings its own primary safety benefits. Although it is true that modern traction control and stability systems can prevent wheelspin, four-wheel drive permits more of the available engine power to be used in conditions where traction is limited. This can be important when trying to get a vehicle quickly out of danger, for example, at a road junction in snow or icy conditions. Further benefits come from the unseen Electronic Stabilisation Programme that can detect the onset of a skid even before the driver. In such circumstances it will automatically brake an appropriate wheel and adjust engine power to stabilise the skid, protecting the driver and occupants from potential loss of control. This system is also effective in high-speed off-road driving. Drivers who provoke the intervention of ESP for the first time will be amazed by its abilities to keep the driver out of trouble. However, it must be remembered that it will not allow the laws of physics to be broken. There are still limits to how much it can protect the driver who enters a corner too fast. Touareg V10 TDI models are fitted with self-levelling air suspension. This feature may also be ordered as an option on all other models. As well as automatically levelling the vehicle to correct height irrespective of the load carried, the Continuous Damping Control (CDC) system constantly adjusts suspension damping in accordance with prevailing conditions. This highly-sophisticated system can raise the suspension to clear obstacles in off-road driving yet automatically lowers at speed for on-road stability. A tyre pressure monitoring system, which warns if a tyre or tyres are losing pressure, is a further safety-related option. Safety in off-road driving Off-road vehicles generally have a higher centre of gravity than road cars, but the Touareg is helped by having a cabin position that is low, relative to its class-leading ground clearance of up to 300mm.
For stopping and re-starting on steep hills, a special hill-start feature comes automatically into effect on all models with automatic transmission to prevent the vehicle from rolling backwards. To move forward, the driver presses the accelerator with ‘D’ engaged. A hill-descent feature provides additional safety when driving down very steep, slippery hills. With low-range selected on the transmission, the driver determines the speed with the accelerator or brake. When the onset of a skid at any wheel is detected, the system controls braking to individual wheels and moderates engine power to stabilise the vehicle and maintain a safe descent. This considerably reduces the chances of a vehicle running away out of control in challenging off-road driving, although again the laws of physics will still apply. Touareg models with the five-inch colour-screen information display can display the direction in which the front wheels are pointing. This provides additional safety off-road when deep ruts or slippery conditions are encountered. Finally, there is one area where Volkswagen has chosen deliberately not to help the driver. This is when traversing steep gradients. For example, the Touareg may be driven sideways along a gradient of up to 35 degrees, which is steeper than 1 in 2. Well before the car gets to this angle the occupants will feel that it will tip over and the vehicle will be kept in a stable condition. It is Volkswagen's view that a driver who has an instrument that warns of where the limit is will be more likely to take the vehicle to extreme positions where the risks of tipping the vehicle over are greater. |
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