We’d heard about Rally1 cars taking heavy hits before the season began. Neuville dropping his Hyundai i20 N Rally1 down a ravine in testing was a big hit – but us punters only saw grainy mobile photos circulated on social media. Also, it was upside down.
Adrien Fourmaux’s massive Monte Carlo Rally shunt put the structural integrity of these new machines to the fore yet again. He overcooked it into a left-hander and clipped a bank that sent him flying over an Armco barrier on the other side, launching his Ford Puma down a steep bank below.
Damage to his car was extensive. It looked like a bomb had gone off. Or a plane had crashed. Parts had flown off the car as quickly as the car had flown off the stage.
Oddly, this was a good thing. Sort of.
On the latest episode of SPIN, The Rally Pod, former Toyota, Mistubishi and Subaru sporting director George Donaldson explained the philosophy behind the new spaceframe design, and why it made such a difference to how the new cars coped with such huge impacts.
“The main concept of this was to reduce the cost. It is cheaper to build a spaceframe chassis than it is to convert a road car into a rally car and strengthen it around accordingly,” explained Donaldson.
Cheaper doesn’t mean less safe. But what it does mean is the way it protects its occupants and absorbs impacts has changed somewhat.
Instead of retroactively adding extra layers of safety and protection in the road car conversion process, as was the case with previous generations of rally cars, now rollcages are part of the base design philosophy from day one.
“That said, the traditional car chassis is a fabulously crushable structure: you can strengthen it and make it stronger to take repeated crush events, as we get in rally and is traditionally done with a rally car,” said Donaldson.
“But [with the previous WRC cars] the rollcage is inside the car. The rollcage is not for instance inside the door skins, or right round the front outside the wheels.
“The opportunity with these spaceframe cars to make a massive amount of extra crush zone between the impact points and the drivers has been huge. In some cases they will have tripled or even quadrupled the distance from the occupant to the initial point of impact in a crash.
“So that’s a crushable zone, it will be mild-steel type rollcages that give and absorb the impacts when they go off downhill. But the result is also that the bodywork on the car is literally just a material like carbon fiber, just panels clipped, bolted, riveted, whatever, onto the car. I know the car looked terrible but basically the passenger shell had a great deal of integrity.”
The end result is cars that outwardly look like they’ve not coped well with being crashed, even when they have. But, while certain types of impact protection may be much improved, Donaldson believes there are still a select few weak points in the new cars.
“My feeling is, when the old steel cars crash, you’ve still got a steel roof and a steel floor underneath you,” Donaldson added.
“Now these cars will still have some sump guards on them but we see sump guards getting ripped off. I quite like the idea of a steel skin that has a monocoque element so that it doesn’t get stripped away. We’re going down through trees; there could be a tree stump sticking up.
“OK, a roof’s not necessarily going to stop that anymore than a rollcage is but I still feel there’s brush that can come into the car, that this kind of thing [steel panels] stops.”
In the case of Fourmaux, the new safety cell design did its job. He walked away with little more than a sore foot and co-driver Alexandre Coria was also uninjured. And one key panel of the car which didn’t fall away in the impact was the front portion of the roof – vitally important in Fourmaux’s case as his car rolled down the hillside. And the underside also coped well.
“One of the weak points of the [old] car was penetration from beneath and from in behind the wheelarch. I believe that has been greatly improved,” concluded Donaldson.
“It’s a great step from the FIA in that degree of integrity. I think it could have been done with a steel monocoque but speaking to a couple of the teams, they seem very happy with the change.
“The fact is we’ve got the crews further away from the start point of the rollcages – that’s good.”
