FWD & RWD - Safety

Safety

Today will talk about frontal impact rather than side panel impact. Because the different structure will affect the frontal impact, there is not any different on the side panel. First we need to know the different engine arrangement for RWD and FWD.

Front Wheel Drive engine arrangement

Rear Wheel Drive engine arrangement

According to the NURO NCAP (New Car Assessment Program), there are two kinds of frontal impact 40% frontal impact and 15% frontal impact. The picture below shows the test.

http://www.euroncap.com/tests/frontimpact.aspx

40% Frontal Impact

As we can see from the left the FWD engine positioned parallel with the car’s width. When the frontal impact happened, the engine will accept part of the impact energy. That is the reason why Volvo remain using this structure.

When RWD vehicle accept the energy form outside, the engine and transmission will easier to remove into the driver’s space, which is dangerous for drivers.

15% Frontal Impact

This test will not affect engine and transmission, but the basic structure will affect the affect safety characteristic. We need to consider the front wheel’s effect, because of the wheel may remove into the driver’s space.

The lower BMW shows it have more space in the square than up SKODA. So the RWD has more space let the front wheel to remove. Two pictures below show the real test results.

Skoda Front Wheel Drive

BMW Rear Wheel Drive

The lower photo’s front wheel apparently damage driver’s leg. The RWD drive has enough space for his leg (up one).

Rear Wheel Drive

Front Wheel Drive

But this is not a theorem, for example in north America 25% frontal impact, the front wheel drive Honda Accord gets the highest score which is high than rear wheel drive BMW 5 series. The success must be contributed to the designing, which can make up the front wheel drive's disadvantage.