In an interview with Reuters, Patrick Head admits that the 2005 season has been difficult.

"The first part of this year wasn't brilliant," said the Englishman, "but it was sort of reasonable and the second part of the year has been pretty unimpressive.

"Our expectation that we would strengthen our position all the way through the season didn't stand up but we are confident we will be strong next year," he added. "We've sorted out a lot of the problems that we had with our wind tunnels, we are now getting more runs per day of good quality aero work."

It is widely believed that Head was moved sideways at WilliamsF1 in order to promote (the younger) Sam Michael, thus giving BMW the youthful image that it sought. Asked if, following BMW's departure, he might return to his former role as Technical Director, Head said: "My interest at Williams is to assist Sam and to work in the factory to develop our capabilities so that Williams comes back to a competitive position.

"It is not part of my life plan or interest to demonstrate to the outside world that I'm a decent engineer," he continued, "I have enough self-confidence to know that. From my early 20s to early to mid-50s I was used to doing seven days a week and 14-hour days and I don't have an interest in taking that approach."

For 2006, there will be many changes at WilliamsF1, as the team enters a (one-year) partnership with Cosworth, which will provide the team's 2.4 litre V8 powerplants - though they have to be paid for, as opposed to the 'free' BMW units they've had since 2000. While the team will also switch back to Bridgestone after five seasons with Michelin.

"Unless somebody is producing an engine that is very special indeed, we have no reason to think that our engine next year will be anything other than competitive," he said. "The problem will be whether it will have enough resource around it through the season to develop during the year and the answer at this stage is no.

"But it's one of the things we are working on," he continued. "There is in the contract an agreed update during the year but there's no way it will have the white heat of development that, say, the Honda engine has on it."

The Englishman, couldn't resist a dig at BMW, clear evidence of the rift that has been growing for some time: "We've obviously seen what BMW were offering us and we've seen what Cosworth are offering us and the latter is quite a lot higher than the spec of the former," he commented. "A long way."

Although partner Frank Williams has - for the most part - attempted to keep the peace with BMW, and in particular the German company's Motorsport Director, Mario Theissen, Head has made no secret of his feelings.

Asked of his thoughts of BMW's own F1 venture, which will be headed by Theissen, Head commented: "I think Mario has got a pretty big rod on his back. As I understand it, he's told the BMW board not only that he will arrange that the team is fully funded through sponsorship but also that they will win the championship in 2007. Well, good luck to you Mario.

"In order to get the board to approve the decision to buy Sauber, he made those two promises to them," he added. "That's what we're told by other board members, anyway; The board members who were present but didn't agree with the joint decision that was made," he adds, referring to the Sauber buy-out.