• W223 S-Class is the first production car with rear airbags.
• Uses a tubular structure for flexibility.
• Could pave the way for future cars.

Airbags, one of the most significant inventions in vehicle safety. The US National Highway Traffic Safety Administration (NHTSA) estimated that more than 50,000 lives were saved by the airbag in the span of 30 years (1987 to 2017), and that’s in the US alone.

It’s a simple concept – a flexible fabric bag that quickly inflates in the event of a collision to soften the impact between body parts, particularly the head, and hard surfaces of the car.

In modern cars, airbags can be found in the steering wheel, dashboard, and structural pillars. These are the front, side, curtain, and sometimes knee airbags. 

And that was it for a while, it would’ve appeared that we have reached the maximum number of airbags in a car’s cabin… until in 2020 when Mercedes-Benz presented the all-new W223 Mercedes-Benz S-Class.

Also read: All-new (W223) 2021 Mercedes-Benz S-Class launched in Malaysia; PHEV only, 510 PS/750 Nm

The W223 Mercedes-Benz S-Class is the first production car to offer full-frontal airbags for rear passengers. This is not to be confused with side or curtain airbags that stretches to the rear windows. 

Unlike traditional bags fitted on steering wheels, the rear airbags use a tubular design - meaning it’s not the entire structure that will be filled with pressured air, just the tubes while the rest of the structure is flexible. Think trampolines but not quite so elastic.

During severe frontal collisions, the rear airbag can considerably reduce the loads acting on the heads and necks of occupants on the outer rear seats.

The rear airbag uses a special tubular structure which is rapidly inflated by compressed gas from a cold gas generator. The space between is filled with ambient air. 

Patented valves ensure that the air is retained when the occupant is immersed in the airbag, creating the protective effect. The airbag volume is configured so that the rear occupant wearing a seat belt can be protected before contacting the front seats.

One of the biggest challenges was to design an airbag structure that caters to humans of all sizes and seating behaviour. Because of this, Mercedes-Benz says that designing a rear airbag for a frontal collision requires a different concept from a conventional driver or front passenger airbag. 

The spatial parameters are different, occupant behaviour varies widely, and the airbag must be accommodated in the adjustable backrest of the front seat.

Also, they have to take into account the possibility of people or objects that could be in the deployment zone during collision. Hence, special attention was given to the gentle deployment of the airbag, which the tubular structure allows.

The rear frontal airbag module is placed in the front seats and in the event of a collision, the inflating tubes give way when contacting obstructions like say, a child seat in the rear-facing position. So rather than crashing into obstacles it encounters, it sort of wraps around it and adapts to the situation of the crash.

Just like in the front seats, the airbag enhances the restraining effect of the belt system, and can support the head and neck to significantly decrease the loads on them.

It could mean the difference between life and death in a crash. And if you think about it, the most important people often sit at the back, whether it’s bosses or children, and you would want maximum protection in the unfortunate event of an accident. 

If history is any indication, rear frontal airbags have the potential to be introduced by other car manufacturers, just like how almost every car in the world now features electronic ABS and electronic stability control.

It’s quite amazing how many technological features were pioneered by the Mercedes-Benz S-Class, but we can reserve that topic for another day. For now, if you're keen on experiencing the all-new S-Class, visit here.

This post is sponsored by Mercedes-Benz Malaysia.