Red Bull head of aerodynamics Dan Fallows believes his team can overcome the deficit it has to championship leaders Mercedes on the strength of the car's aero performance alone.

Red Bull has made its worse start to a season since 2008 this year and has not been shy about venting its frustration at engine-supplier Renault. It is hoping the French manufacturer will bring significant updates to the Spanish Grand Prix, but Fallows is of the opinion that it can make up the shortfall to the front of the grid with aero gains.

"We went into 2015 knowing we had a long way to catch-up," he said. "Everybody knows where our major deficit is but frankly, why we're being outperformed is irrelevant. We have it in our power, in the aerodynamics department, to do something about it.

"F1 has plenty of performance differentiators: there's the driver, the power unit, the aerodynamics, the use of tyres and so on, but there's really only one aspect over which the aero team can have a fundamental impact - so we go into the year knowing what the deficit is and working on the basis that it's our job in this department to close that gap. We can do it because we have to the tools to do it, we've done it before and the aim is to do it again."

He added: "I'm never happy with our cars, never have been, even when they've been dominant. I think if you were happy with them, the instinct would be to back off a bit - and that's not what you want in F1."