But for now, it remains unconscious, in a coma."However, today's comments suggest what limited progress
there was has stalled.
Bianchi was put into an artificial coma after suffering head injuries during a high speed smash at a rain-soaked Japanese Grand Prix last October.
He started showing early signs of recovery a month after the incident, when he was taken out of the coma and repatriated to his native France.
But Bianchi remains unconscious in a hospital in Nice and father Phillipe confirmed today in an interview with French radio that he was feeling increasingly "less optimistic" about his son's fate.
He said: "In general, progress needs to be made in the first six months. It has been nine months now and Jules has still not woken up and there is no significant progress.
"As time goes by, I am less optimistic than I might have been two or three months after the accident when we could have hoped for better progress.
"There comes a point when you have to just keep your feet on the ground and realise the gravity of the situation."
In comments that highlight the severity of the 25-year-old star racing driver's condition, Phillipe Bianchi hinted at the difficult decision the family may face.
Referring to fellow F1 champion Michael Schumacher, who is also recovering after a skiing accident left him with brain injuries, Phillipe Bianchi described the difficulty his son would likely endure, even if he were to regain consciousness.
"If he has to have very severe disabilities we are convinced that this is not at all what Jules wants. We talked about it," he said.
"He told us that if he happened one day an accident of the type of Michael Schumacher, it would have been if only the handicap of being able to drive, it would be very difficult to live it. Because it was his life."
Phillipe Bianchi also spoke movingly about how life "stopped" after the crash.
"It's hard to get up in the morning saying that you are not sure your son will live and that every day it's like that," he said.
"We had an extremely bright son, who lived his passion, traveling in all countries of the world, and overnight this son that you had every day on the phone ends up on a hospital bed between life and death."
Last year's crash happened when Bianchi's car hit a recovery vehicle that had been attending an earlier track-side incident.
The racing driver, who turns 26 on August 3, underwent surgery soon after and was then moved to intensive care.
Speaking in April, Bianchi's father sounded a more upbeat message.
"The only thing we can say is that he's fiercely fighting as he always did, before and after the accident," he said at the time.
"From a medical point of view, his condition is stable.
"All his organs are working without assistance. But for now, it remains unconscious, in a coma."
However, today's comments suggest what limited progress there was has stalled.