Red Bull opts for late car build ahead of 2015 F1 testing

With the first pre-season test kicking off at Jerez in Spain on Sunday, Red Bull's new Renault-powered challenger has only just begun construction at its Milton Keynes base.

That move comes after design chiefs were given the green light to maximise development time on the car to ensure the team did not let any opportunity go to waste in its bid to topple Mercedes.

Team principal Christian Horner said during a Red Bull media event in Milton Keynes on Tuesday that, although there was no danger of missing the first test, things were still pretty fraught at the factory to get the car finished and shipped to Spain.

When asked by AUTOSPORT about if the car was ready to run, he said: "Not yet. The car is flat out in to car build at the moment.

"It's probably the shortest production and assembly in our previous ten seasons.

"It is unbelievable what the factory have turned around so far. But still there is plenty to do before Sunday."

Horner said he was encouraged by the windtunnel data that had been produced for the new car, as Red Bull prepares to have a smoother pre-season than the disaster it endured in 2014.

"After the first test last year, hopefully this one cannot be any worse than that," he said.

"I think we managed about four laps over four days and car would either stop on track or set on fire.

"It has been a far more positive winter compared to last year. We know where the benchmark is and what we need to achieve.

"As the team continues to evolve and grow, it has been I think the most impressive winter we have had as a team.

"That is in terms of everything coming together - in terms of the car being produced in the shortest time ever, and the design hitting all their deadlines and targets."