2014 runner-up Red Bull is reportedly pushing the boundaries with its readiness for the new season.

Team boss Christian Horner has already admitted that, in the last few days before the first test at Jerez kicks off, the 2015-spec RB11 car is "not yet" ready.

"There is still plenty to do before Sunday," he said this week.

Now, Italy's Omnicorse claims the last 100 per cent Adrian Newey-designed Red Bull may not even have passed the FIA's mandatory crash tests.

In the not-too-distant past, the crash tests only needed to be cleared ahead of a car's actual grand prix debut, but now they are necessary even for testing.

It is believed Red Bull is pushing the time limits with 2015 crash testing not due to a problem with the chassis, but simply to give designers and engineers every possible minute to design and develop the RB11.

"Mercedes for sure are the benchmark," Horner said. "They go in as the reigning champions and the favourites for this year and they had a significant advantage at the end of last year."

Omnicorse said Red Bull, to unveil the car on the first morning of the first test at Jerez on Sunday, will try to pass the FIA tests at the Cranfield Impact Centre on Thursday, leaving just two clear days until the RB11's Jerez debut.

A team spokesman said he is confident Red Bull will be ready for Jerez.

Horner added: "This is probably the shortest production and assembly time in our ten seasons -- it is unbelievable what the factory have turned around so far."

Later on Thursday, McLaren will launch its Honda-powered MP4-30 online, followed a day later by Ferrari and Sauber.

Toro Rosso will then launch its STR10 at Jerez on the day before Sunday's first test day, while Williams, Mercedes, Red Bull and Lotus all plan to reveal their cars just before the green light shines at the southern Spanish circuit.

Force India is skipping Jerez, and the winter plans of the ailing backmarkers Caterham and Manor are not known.

(GMM)