The fuel flow limit was introduced as a way to overcome safety concerns brought about due to the introduction of the turbocharger, the FIA said at a technical press conference on Friday evening.
In a technical presentation to a packed out room of journalists, FIA Head of Powertrain Fabrice Lom joined Charlie Whiting, the FIA Race Director to explain the inner workings of the fuel flow sensors and the justify their purpose.
This came in response to Red Bull’s Cristian Horner’s comments asking whether the limit was really required.
“The biggest thing out of this, irrelevant of the hearing, is that we need a better way of measuring and monitoring the fuel, or get rid of it totally and say you’ve got 100kg and that’s your lot. I think that would be the easiest for the FIA and probably for the teams.”
Armed with a whiteboard and blue marker, Fabrice Lom explained that without the limits, the differences in speed around the circuit could be enormous, posing a huge safety risk and encouraging a style of racing that the FIA was uncomfortable with.
“If you have no fuel flow limit, the fastest thing is to use a huge boost at the beginning of the straight and then lift off.”
Lom then used the comparison of cars from the over two decades ago when 1.5 litre turbo charged engines were used.
“They were able to do 1,500bhp. Then you can also do 3kg on one lap and 1kg on another lap and so at one point one car will be accelerating very quickly and another will not. There will be huge and, we think, very dangerous difference of speed on the same lap, with a driving style that is not really F1.”
“We were really afraid of this type of driving, which can be very, very dangerous.”
The head of powertrain also explained the extensive levels of calibration that the sensors are subjected to in order to satisfy the +/- 0.5 % tolerance requirement. Four sensors at a time are calibrated by a company ‘Calibra’ against a single control sensor and those that do not satisfy the tolerance are discarded. According to Lom, the majority of the sensors are within a +/- 0.25% tolerance. However Lom would not indicate whether this related to the specific Red Bull case.
Teams are only told that their cars are not satisfying the fuel flow requirement if they exceed the limits in a single lap by 1% for 10 seconds per lap, or an equivalent of 3 grams per lap. If the cars are reaching 3 grams extra per lap, for that moment they are using approximately an 100.2kg/hr. This equates to 189 grams of fuel over an entire race, offering a tangible advantage to the team.
Given the fact that the FIA does allow for the teams to correct their fuel flow usage and has quite a forgiving system to an extent, it begs the question: how much of an advantage did Red Bull have in Melbourne?
Image by XPB.