Toro Rosso, Williams and Honda have revealed what they believe caused the flash fires which were seen during pit-stops at the Hungarian Grand Prix.
All three teams saw brief flash fires during one of the pit-stops and many initially thought there was a universal problem with the refuelling rig. However Honda have revealed they believe their fire was thanks to the refuelling hose not being fitted squarely onto the car.
Williams have now said that they think their problem was caused by pressure in the fuel tank which caused some excess fuel to come up inside the hose.
“We planned a two-stop race but put enough fuel in so we had the possibility to go one stop,â€ Rod Nelson, Williams chief operations engineer explained in the Williams official podcast.
“And on the basis of Coulthard’s performance against Webber – Coulthard started on the option tyre – we decided to go for it. We were nowhere by that stage anyway because of problems at the start, so we went for it with Kazuki which meant we were putting a lot more fuel in the tank than you normally would, certainly.
“It was very hot so fuel was vaporizing at a massive rate and that causes some foaming within the fuel hose. You get fuel up the vent hose and some of that splashed down into the car connector just as they took the rig off. As soon as you drive out, that splashes over the exhaust system and you have a small flash fire,â€
Toro Rosso have yet to reveal what their hypothesis is however they have confirmed they do not believe it is a problem with the refuelling rig itself. “I can confirm it was not a problem with the rig,â€ a spokesperson from the team said. “The problem has been resolved to make sure it does not happen again, but there is no further comment from our technical group.”