Crash & learn

When creating a modern F1 car, designers major as much on safety as speed. Robert Kubica is one who’s thankful they do…

By Rob Widdows

Grand prix racing will never be utterly safe. But the fact that more people die falling from horses than they do in racing cars is in part an indication of the major improvements that we have seen in racing car construction over the last three decades.

When David Purley crashed at Silverstone in 1977 he was lucky to survive, his extreme fitness and mental strength playing a significant part in the immediate aftermath of such a huge accident. When Robert Kubica crashed in Montreal in June he survived thanks to a quantum leap in the way that grand prix cars are now designed and constructed.

There is always an element of luck, but nobody would dispute that the measures taken by the FIA and the Grand Prix Drivers’ Association in the years between the Purley and the Kubica incidents have made the sport enormously safer. When Mike Pilbeam, a highly respected engineer, designed Purley’s LEC CRP1, he was working with what are today considered to be fairly agricultural materials, a ‘car made of tin’ as it’s now described. When BMW-Sauber technical director Willi Rampf started on the current BMW F107 he was in a different world, working with carbon-fibre and within the confines of the FIA’s crash test requirements, which have been steadily refined over the years.

Purley’s team manager Mike Earle feared the worst when he saw his driver slumped in the wreckage (page 94). There was a fleeting moment of doubt for Rampf in the team garage at Montreal, too. “He did not move in the cockpit, so I was quite concerned. Anything could have happened, you know, but we heard very quickly that he was stable. So it was a big relief, yes.”

According to analysis by the FIA, the g-force at the front of Kubica’s car was 75g and at the rear 28g. “In an accident like that you can never be confident, or comfortable, that the driver will be unhurt,” admits Rampf, “because this is something you cannot ever simulate and there are so many different factors, and forces, involved. For example, how much energy has the nose section taken away? How much energy has the chassis absorbed? At what angle has the car hit the wall – was it 90 degrees, or 30 degrees, or sideways? All these factors are so important for the end result of such a crash. You cannot ever say that a certain angle of impact is the safest: if the car hits head-on then a lot of the energy will be used up by the nose section but then it will also disperse into the chassis, so it can be better if there is a slight angle so that the car bounces out of the wall and slides away from the point of impact.”

Grand prix car designers and engineers will always have ultimate speed and performance as their priorities, working as close to the edge as possible, and weight is the enemy. But the FIA, using data from previous accidents, has drawn up a robust set of rules with which all manufacturers must comply if they are to produce a car that will pass the mandatory crash-test examination of its integrity.

“We do not work as closely to the limits as we could if there is something we can do to improve the safety beyond even the FIA’s strict regulations,” says Rampf, “and we will make any small developments we can to ensure the safety of our drivers. We are not saving the last 100 grams when it comes to safety. For example, when we look at local stiffness, or even the global stiffness, of the chassis we are already ahead of the FIA requirements with this car. We pay particular attention to the importance of the nose structure as this is the front crash structure, and so you build it to make sure you are safely within the regulations. This is the same with the chassis itself and the suspension – so we are well above the safety requirements in these areas.”

It is not simply the integrity of the car that has seen such major improvements since the dark days of the 1960s and ’70s. New technologies have allowed designers to place their drivers in a safety cell uncluttered by solid objects that can break loose on impact. When Purley crashed in 1977 he was sitting on top of the fire extinguisher bottle and surrounded by fuel tanks. Mercifully there was no fire, but the extinguisher came up underneath him as the chassis crumpled, causing terrible damage to his pelvis. Then there is the HANS device, a head and neck restraint that is now mandatory in grand prix racing.

“Yes, the HANS device plays an important part in an accident,” says Rampf. “It ensures that the head and the neck are very well supported, these parts of the body being very exposed to the g-forces of a crash. In Montreal Robert suffered some concussion but he had no injuries to his neck or head, and no headaches, nothing. So HANS did its job there.”

There is always more to learn about safety, and BMW has been analysing the chassis of Kubica’s F107. “We will not use that chassis again,” explains Rampf, “but we have done some investigation and simulations to see if the failure mode was exactly as we had predicted. And we will do some further analysis to improve our crash simulation programmes, to assess whether we can do more to make the chassis even stiffer, even safer for the driver.

“There is always something we can learn and in a very heavy crash like this one there are loads on the chassis which are very difficult to calculate. For example, the car has crashed very heavily at the front end but maybe there is a small crack somewhere else, maybe towards the back, and you never see that immediately. From this data you can make some small modification and make sure it does not happen again. Since Montreal we have made some small corrections, some small overlaps in the construction to improve the process even further.”

Remarkably, the BMW engine survived almost intact. “Yes, the engine went back to the factory and it was in a state where we could run it on a dyno,” reveals Rampf. “But the biggest improvement we have seen, by far, is in the structure of the chassis, the monocoque where the driver sits. In this case, the tub did not collapse at all and everything around the driver was in correct shape and there was no damage that could have created problems for his legs or for his body.” 

There are those who joke about the days when sex was safe and motor racing was dangerous. This is no longer funny – there would be so many more of our heroes alive today if only we had known then what we know today. Motor racing will never be free from danger but thanks to pioneering work by Jackie Stewart and the GPDA, along with some tough talking from the FIA, today’s drivers have a markedly better chance of enjoying a happy retirement