Michael resigns, Coughlan joins Williams

On the back of a troubled start to the campaign, Michael and Tomlinson have both decided to leave the outfit at the end of the season when their current contracts expire.

Team boss Frank Williams said the departure of the two would allow the team time to sort out replacements that would help turn around its situation.

"Both Sam and Jon are talented and driven people who have worked hard for Williams over 10 and five years respectively," he said. "Nonetheless, they have recognised that the team's performance is not at the level that it needs to be and have resigned in order to give the team the opportunity to regroup and undertake the changes necessary to get back to the front of the grid.

"Both will continue to work in their present positions through until the end of the year to ensure that the team maintains focus and momentum during the 2011 season. We are very grateful to Sam and to Jon for their professional approach."

In the wake of the decisions of Michael and Tomlinson, Williams has signed former McLaren technical chief Mike Coughlan - who left the Woking-based team in the wake of the 2007 spy scandal - as its new chief engineer.

Williams said: "Mike Coughlan is a fine engineer with extensive experience across Formula One and both civil and defence engineering.

"He left Formula 1 in 2007 because of conduct which he acknowledges was wrong and which he profoundly regrets. His two year ban from the sport expired some time ago and Mike is now determined to prove himself again.

"Williams is delighted to be able to give him the opportunity to do this and we are very pleased to have one of the most talented and competitive engineers in the sport helping us to return to the front of the grid.

"This is the first step in re-building and strengthening our technical group. We will announce the next steps as they develop."

Coughlan added: "I am grateful to Williams for giving me this opportunity. My experience in 2007 was life-changing. Since then, I have endeavoured to put my skills to good use in the design of the Ocelot vehicle whose purpose is to transport soldiers in safety. I have also enjoyed my time with Michael Waltrip Racing: they are an excellent race team and I wish them well for the future.

"Now, I am looking forward to returning to a sport which I love and to joining a team that I have admired for many years. I will dedicate myself to the team and to ensuring that we return to competitiveness while respecting the ethical standards with which Williams has always been synonymous."