[歐洲賽車比賽] Con-rod failures caused Peugeot Le Mans disaster

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Three weeks after the 2010 Le Mans 24 Hours, and after inspecting the cars that contested this year's event, Peugeot Sport looks back at the problems that affected the 908 HDi FAPs in the French race. The first of the four 908 HDI FAP's to retire was the pole sitting no.3 car which was reported to have had some kind of chassis failure. Peugeot Sport's Technical Director Bruno Famin reveals what went wrong; "to begin with, with regard to the N°3 car which retired 2½ hours into the race, we have found a quality-related problem concerning the production of the tub at the point where the lower front-right suspension wishbone is attached to the chassis. This is the same tub that won the 2009 Le Mans 24 Hours and the 2010 1,000km de Spa-Francorchamps, and - like every 908 chassis - is regularly inspected at the factory using sophisticated tools that enable us to detect ageing or damage to the carbon. The problem in this case, however, was due to a totally undetectable defect which resulted in a premature and sudden failure of the mounting point."



The other three 908's including the privateer ORECA car all retired with catastrophic engine failures, costing the marque an easy win. Famin reveals that the problem has been found.
"As far as the engines are concerned, it didn't take us long to confirm that all three engines suffered the same problem, i.e. conrod failure, although the cylinders that were affected were different. Further investigation has just revealed that the particularly severe conditions encountered at Le Mans in June led to excessive overload of the V12s in question. Indeed, the track benefited from high levels of grip this year, so the engines spent longer at full throttle than we expected. At the same time, the weather stayed cool and, unlike previous years, the air/air intercoolers did not become clogged up.
The filling of the combustion chambers remained extremely efficient throughout, which in turn meant that the performance delivered by the engines was particularly high. Okay, the conditions were the same for all competitors, but we were running new conrods this year. That said, they had undergone thorough testing on the bench and during the numerous on-track simulations we carried out upstream of the race.
We didn't observe the slightest problem with them during any of these test sessions, so there was
nothing to suggest that we were closer to the limit than we had imagined. As it turned out, the race
conditions tipped us to the wrong side of that limit. Having contested the Le Mans 24 Hours three
times, we had every faith in our processes. The evidence now points to the fact that this wasn't the
case and that despite our growing experience, it is very difficult to master absolutely everything. The
conditions we face at Le Mans differ every year, as do the constraints to which the cars are subjected.
It is clear that we need to reinforce our validation procedures."