Robert Kubica still has 'questions to answer' for Formula 1 return

Questions remain about the viability of Robert Kubica making a full-time return to Formula 1 in 2018, Renault have admitted.

Kubica, who suffered career-changing arm injuries in a rally accident six years ago, completed the equivalent of two race distances of the Hungarian GP in Renault's 2017 car at the Hungaroring test ahead of F1's summer break.

The Pole had previously driven Renault's 2012 car in two separate outings this year as the prospect of a full comeback to the sport first emerged.

But Renault have indicated that Kubica's outing in Hungary was far from conclusive.

"What happens next: good question. We don't have all the answers that we potentially wanted to get from that test, after his test," team boss Cyril Abiteboul said.

"In relation to that, Formula 1 is very restrictive in terms of tests you can do, so in a perfect world we would want to do more of this type of test to see if he can race again at the level that he and we could have wanted. It may or may not be possible. We will see."

While no more in-season tests are scheduled this year, it has been suggested Kubica could feature in a Friday practice session before the end of the season.

"There are various things to do to come back into a racing car at this level, a car that is extremely different from the car that he's been driving six or seven years ago, as well the car that he drove in the test that he has done in Le Castellet, which was a car from 2012, is much lighter, less downforce," said Abiteboul.

"So without going into too much detail, you could see what it could involve to go one step further. The problem, as I said, is we are restricted in our ability to test and to reproduce this test. And in addition to that, testing in isolation, private test, one car, in control on the amount, without rain, without the first-lap action you can always encounter.

"All of that needs to be factored into the decision of pursuing or not pursuing. We would all like Robert to be back, but it has to make sense."

Were Kubica to return to Renault for 2018, it would be at the expense of Jolyon Palmer, who is yet to score a point this term.

"It is well reported that Nico has a multi-year contract when Jo has a one-year contract," confirmed Abiteboul. "So obviously we have one driver to decide for next year.

"We'll also need to be consistent with the timing of deciding for a second driver," continued Abiteboul. "The market is starting to sort of go, with the different announcements this week of Ferrari and McLaren, and I expect there will be some other announcements at some points, because usually these things do not go in isolation, so we cannot just be sitting on our work and making up our plans and our timing ourselves. It has to follow the timing of all the drivers."

Were Renault to drop Palmer, Kubica could face competition for the vacancy from Sergio Perez and Carlos Sainz.
Toro Rosso's Sainz has made plain he wants a promotion up the grid while Perez, who turned down Renault 12 months ago, has yet to re-sign at Force India despite the door closing to him at Ferrari when Kimi Raikkonen signed his one-year extension.