WRC - Safety Upgrades

[speederbee]

This looks like a very dangerous crash to me. The car is traveling at decent speed when it hits an immovable object directly where someone is sitting. That's a huge amount of force in a concentrated area in a sudden impact.

Don't be fooled by crashes that "look big" but actually don't result in big forces on the occupants. For example, a car that goes off the road at 120kmh, and rolls ten times, before finally coming to a stop 400m away in a field. Looks big, but all that energy is dissipated gradually over time as the car slows down during the crash. Much less dangerous.

[Fast Eddie WRC]

Exactly, it's the 'sudden stop' crash like this that causes the worst injuries.

And, with all but the Rally1 cars, it seems the sudden stop side-impact is the most dangerous of all, with little energy dissipation and nothing can realistically be done to add more protection.

[denkimi]

Airbag is not an energy absorbing feature but an additional way to restrain the occupant's bodies.

Yes it is. It functions as a crumble zone for the body. It slowly absorbs the energy that of the occupants body that would otherwise get abruptly absorbed by solid things like the steering wheel.

In fact, being constrained by a bucket seat and a 5 point harness is worse than being constrained by airbags. If the car comes to a solid stop, bucket seat make your body also come to a solid stop, creating enormous amounts of G's. If you are constrained by an airbag, the impact is spread out over a longer time, drastically reducing G forces.

But the issue with airbags is that they only work in one direction, while a crash can come from anywhere. Plus, rally cars are filled with big metal tubes and little space to actually move, making seat and harnesses a more reliable solution.

And, with all but the Rally1 cars, it seems the sudden stop side-impact is the most dangerous of all, with little energy dissipation and nothing can realistically be done to add more protection.

Yes you could. As I said before, you could put something between the front and rear wheels to act as a crumble zone.
It doesn't even have to cover the whole side. A bar just above the ground would help in most of the dangerous sideways accidents, hitting trees and poles. Something like the 2017 cars had, but then made of something that works as energy absorbing.

[Mirek]

Yes it is. It functions as a crumble zone for the body. It slowly absorbs the energy that of the occupants body that would otherwise get abruptly absorbed by solid things like the steering wheel.

In fact, being constrained by a bucket seat and a 5 point harness is worse than being constrained by airbags. If the car comes to a solid stop, bucket seat make your body also come to a solid stop, creating enormous amounts of G's. If you are constrained by an airbag, the impact is spread out over a longer time, drastically reducing G forces.

But the issue with airbags is that they only work in one direction, while a crash can come from anywhere. Plus, rally cars are filled with big metal tubes and little space to actually move, making seat and harnesses a more reliable solution.

G-force is critical factor mainly for the human brain. With helmet, HANS and the current rally seats there is no point in using airbag. The job to somewhat slow down the brain acceleration is up to the internal structure of the helmet.

For the soft organs in the belly the critical factor is not G-force but organ displacement. That's why the rally belts are faaaaaar better than those in a stock car and why physical condition matters a lot in case of crash.

For the limbs the G-factor isn't important. The injury comes from mechanical damage.