An Audi truism also applies to the A1: The body establishes the foundation for the quality, for the precise, sporty handling, a quiet cabin and safety.
High-strength and ultra high-strength steels of different strength classes make up two-thirds of the A1 superstructure. The strongest of these are the hot-shaped steels. The blanks are heated in a furnace to high temperatures then immediately shaped in a water-cooled pressing die. This rapid change in temperature imparts them with very high tensile strength.
Hot-shaped steels make up 11 percent of the body. They are used for in the area of the passenger cell, in the rear sections of the longitudinal members, in the roof arch and in the A-pillars and B-pillars – in all places where ultra high strength combined with low weight is particularly important. The high-strength and ultra high-strength steels are a significant factor for the low body weight of only 221 kilograms (487.22 lb). The combination of high torsional rigidity, the body structure and the low weight make for a very good lightweight quality value.
Another factor that increases rigidity is the joining method used for the body at the newly equipped Audi plant in Brussels. 66 meters (217 ft) of structural adhesive are used per car, with optical systems monitoring its application in many areas. The adhesive provides for strong and tight connections, often eliminating the need for additional sealing measures and thus saving weight.
The high body rigidity also plays a major role in the excellent acoustics of the A1, which is free of annoying resonances. The Audi development engineers devoted considerable attention to the sound radiation of the large sheet metal panels and their rigidities. All regions at which forces are induced during driving were specially reinforced. A lightweight insulation package provides a premium-level of quietness inside the vehicle.
The A1 is also at the top of its class with respect to occupant protection. In the event of an offset frontal collision, the energy imparted is directed to the side facing away from the collision to keep loads on the occupants to a low level. The B-pillars, the wall in front of the footwell and the rear longitudinal members offer a particularly high degree of protection thanks to their extreme strength. Four sensors that react to acceleration and an increase in air pressure provide the airbag controller with detailed information in any type of crash.
The A1 comes standard with two front airbags, thorax-pelvis side airbags in the backrests of the front seats and curtain head airbags. Belt tensioners and belt force limiters plus the integral Audi headrest system, which mitigates the consequences of a rear-impact collision, round out the package. Isofix child seat anchor points in the rear are standard. The belt status for all occupants is displayed in the instrument cluster.
The new Audi goes well beyond legal requirements when it comes to pedestrian protection. The front bumper, the crossbeam behind it and the hood satisfy all of the key criteria. The hood is secured to the body by two releases, allowing a construction that makes it very rigid and yet low in weight.
Low-speed collisions – the standard insurance category crash and the new bumper crash, both of which are important for determining the comprehensive insurance category – result in no major damage. The damaged elements in the bumper can be replaced individually. The front crossbeam and the bolted-on crumple boxes in front of the longitudinal members are made of aluminum. They form a structure that provides effective protection for expensive components such as the radiator and air conditioners as well as the welded body structure.
Extremely sophisticated: the aerodynamics
With a drag coefficient of 0.32 for the base model, the Audi A1 is one of the best cars in its class. Its frontal area measures 2.04 m2 (21.96 sq ft). The sophisticated aerodynamics are the result of extensive fine-tuning in the Wind Tunnel Center at the Ingolstadt plant. 0.08 was shaved from the drag coefficient during the course of the vehicle’s development, reducing fuel consumption by as much as 0.6 liters per 100 kilometers.
The body has been extensively optimized in every detail, from the wheels to the spoiler lips at the tail lights to the small corners that connect the roof spoiler to the body. Visually understated, they improve separation of the air flow and thus increase aerodynamic stability.
A plastic liner covers most of the underbody, protecting it against salt and stone chipping and providing for a more aerodynamic flow of air. The developers also paid very close attention to the slightest details here – spoilers are integrated in front of the wheels and even at the spare wheel well. The aerodynamic trim panel lowers the cD value by roughly ten percent.
In the A1, the single-frame grille and the surrounding area are completely sealed so that the inflowing air reaches the radiator with virtually no losses instead of becoming turbulent. A stepless radiator fan contributes to this efficiency package.
The A1 glides quietly through the wind thanks to the extensive development work done in the acoustics wind tunnel. The seals, the windows and many details of the body geometry all play a role here. The side mirrors also serve an additional function: their grooves and deflector edges reduce fouling of the side windows and the mirror glass on wet roads.
The equipment and data specified in this document refer to the model range offered in Germany. Subject to change without notice; errors and omissions excepted.