Formula One is under fire again. The safety debate is raging, a consequence of Graham Beveridge's death during the Australian grand prix in Melbourne this month. It is a debate the sport is well used to, one begun by Jackie Stewart in the late 1960s and which last flared up in 1994, after the deaths of Ayrton Senna and Roland Ratzenberger on one terrible weekend at Imola.
This time, however, the focus has changed. For Beveridge was not a driver but a volunteer marshal, and the concern now is not how to protect the sport's stars but to ensure the safety of the thousands of people who line the track at each race. Which leads us to a bitter irony.
The grand prix authorities and teams have spent billions of pounds over the past two decades trying to make drivers invincible to any accident, no matter what the speed. Senna's death, the last driver fatality to afflict formula one, sparked another drastic improvement in the cars' safety features and, as a result, today's drivers are cocooned in a bullet-proof shell which, judging by the four heavy crashes in Melbourne, means they can survive even the most frightening-looking incident.
However, according to some respected members of the grand prix paddock the sense of security that drivers now feel may be the very reason there were so many serious crashes in Australia - increasing the threat to marshals and spectators.
"Racing drivers are always willing to accept a certain level of risk," says Martin Whitmarsh, the managing director of the McLaren team. "So the more they perceive their situation is safe, the more they will extend their envelope of performance accordingly." Which means drivers pushing harder, driving faster and making more risky moves on the track.
"Perhaps they would show more caution," Whitmarsh adds, "if they were not driving a bullet-proof car. That's the nature of all competition, particularly in a sport such as motor racing."
The accuracy of Whitmarsh's description can be seen from the manner in which Jacques Villeneuve - no stranger to massive accidents - hopped out of his BAR-Honda's central "survival cell" after the crash that resulted in Beveridge's death, and hitched a lift back to the paddock on a motorcycle pillion.
But cars will, of course, keep on acquiring safety innovations, and they will keep getting quicker too, so long as the sport's governing body, the FIA, adopts a piecemeal approach to reducing lap speeds. Which can only make it increasingly dangerous for spectators and marshals, particularly at the older circuits where more compromises are made over where they watch from.
Max Mosley, the FIA's president, has already admitted that, because of the newly rejoined "tyre war" between Bridgestone and Michelin, speeds have increased too much, despite attempts to cut them via aerodynamic rule-changes over the winter.
He has promised further action to force speeds down but, whereas he is probably thinking in terms of wings and tyres, now may be the moment for the FIA to grasp the nettle and tackle one of grand prix racing's most sacred cows: Engines.
Since 1994, engine power has been allowed to edge upwards unfettered by any rule restriction. In an effort to attract more major car manufacturers into the sport, the current rules permitting three-litre V10 cylinder engines have been guaranteed until 2007.
There is, however, a growing feeling in the paddock that these 820-horsepower engines should be replaced by high-revving 2.5-litre V6cylinder units, which would develop about 650bhp and add more than four seconds a lap to current times.
"Reducing performance is a difficult question," says Jaguar's number one driver Eddie Irvine. "But a V6 would slow speeds quite a lot and, personally, I don't think that would hurt formula one.
"The noise would be fantastic because the engines would run to 20,000 r.p.m.. People want to hear that sort of thing; they don't really notice out-and-out speed as such, they just want noise and want to believe they are watching the fastest formula.
"Of course, this would also mean there was no need for traction control [which is to be reintroduced at this year's Spanish grand prix] and from my point of view that's a very positive thing. People want to see the cars sideways with the drivers fighting to put the power down. I think the spectacle of 650bhp - or whatever it might be - would be far better than 850bhp with traction control."
The teams have broadly agreed since 1994 that such an engine rule-change would be acceptable. But the FIA has been reluctant to act, preferring to penalise and further restrict the engineering initiative of the chassis manufacturers.
"I think engineers find these restrictions quite frustrating," Whitmarsh says. "They tend to make the overall package that teams produce very similar. I personally would support the move to a 2.5-litre engine, and I don't think our partners Mercedes-Benz would be particularly distressed about it, provided they had sufficient notice."
Patrick Head, BMW-Williams' technical director, agrees that curbing lap speeds by reducing engine power is feasible. But he believes the safety debate should concentrate on enhancing protection for marshals rather than slowing the cars.
All agree, however, that Mosley has a delicate balancing act to perform over the next few weeks. Should there be any more serious incidents in Malaysia or Brazil, the next two world championship rounds, the clamour for action may become deafening.
The most likely response is stiffer aerodynamic and tyre regulations, but perhaps it is time for the FIA to take a longer-term view.
