Kubica rates F1 return chance at '80 or 90%', set to test again

Kubica had to leave F1 after sustaining severe injuries to his right hand and arm in a rally accident in 2011, but completed his first test in F1 machinery since that crash last month at the Valencia circuit.

The 32-year-old drove a 2012-spec Lotus E20 and Autosport understands he will get a second outing with Renault later this month at an undisclosed venue.

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Kubica said his optimism about a possible return to the sport has been boosted since the first test.

"If you asked me how much I was realistically thinking that coming back to F1 was possible [before the test], I would have put myself up to 10% or maximum 20% chance," Kubica told Auto Express at the Goodwood Festival of Speed last weekend, when he drove the car up the hill.

"Because the clock is running - not just the classification, but also [I am] getting older. F1 is going so fast that some people forget - not everyone, but some.

"Because I'm very realistic, and I'm keeping my feet on the ground, I'd put it at 80 or 90% [now]."

Kubica had driven rally cars, competing in the World Rally Championship, but had also sampled sportscars - including the ByKolles privateer LMP1 machine - as well as GP3 and Formula E single-seaters.

He said did not feel like it had been six years since he drove a grand prix car.

"You build up your own question marks, based on how you know yourself and your body, and then if you'd asked me about them after even the first run at Valencia, they were gone, gone, gone, gone," he said.

"Then it becomes much easier than I thought. This gives you good confidence and puts you in a completely different level - of trying to have a better feeling in the car and better performance.

"Once my comfort, or let's say limitation things, were gone in three laps, I could concentrate on trying to get back to the proper rhythm. I'm surprised how it felt; it felt for me like I hadn't driven for one month, not six years."

Kubica also insisted "most of the question marks I had" about how he could perform in an F1 car are now gone.

"My first target was to see if I could be capable of doing it," he said. "So this is more or less done.

"Second, let's say, realistically talking, is raising the game slowly and step by step. F1 is a tough competition and I have been away from racing a long time.

"Actually it was a huge relief for me because this test would have been a case of, 'Yes, I can do this' or 'No, I have to close the door on F1 forever'."