“Triggered by the "moose test" failure, in which early A-Class production cars caused a single-vehicle accident under real world avoidance maneuvering, a number of improvements were made in the W169 model.
The biggest was the immediate fitment of a newly invented device, Electronic Stability Control. To preserve its damaged reputation for car safety and engineering, Mercedes-Benz retrofits every single A-Class already produced with ESC.
The car is constructed with high-strength steel alloys with bonded joints. It has a large number of airbags including optional rear side airbags (for side-impacts in the backseats), optional side-curtain airbags, and standard head and thorax-protection side airbags. The front airbags are adaptive with two-stage gas generators operating according to the severity of accident.
The force exerted by the seat belt system during a collision adapts dynamically depending upon the collision characteristics. The 'active' head restraints (standard for driver and front passenger) give enhanced protection from neck injury, especially during rear collisions.
The angle of the A-pillar is flatter than the windshield angle.”
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