Mr Brady describes himself as a supporter of Tony Blair

The 41-year-old beat Mick Rix, who had been the union's general secretary since 1998, by 4,475 votes to 3,299.

Like Mr Rix, he had been a train driver for more than 20 years, having joined the then British Rail in 1980.

But the two came from opposite ends of the union movement's political spectrum - Mr Brady a moderate, and Mr Rix a self-confessed "awkward squad" member.

Following his shock election, Mr Brady promised "to take the union back to the membership".

"My union's democratic process has spoken and I'm going to listen," he added.

Even before his election, Mr Brady had gained a certain notoriety in the union movement.

In 1995 he was asked to leave a TUC shop stewards' course in Southampton after complaints of sexual harassment from women members, although he was later cleared by an Aslef internal inquiry.

This is not a battle between left and right - it is a battle between right and wrong Shaun Brady Aslef boss sacked for misconduct

And he was involved in a fist fight with Bob Crow, during a trip to the Czech Republic when both were young trade unionists, after the RMT rail union leader took issue with Mr Brady's treatment of other members.

But it was in May 2004 that Mr Brady really hit the headlines after a brawl at a barbecue at Aslef's north London offices.

Mr Brady was subsequently suspended, along with assistant general secretary Mick Blackburn and president Martin Samways.

Mr Samways later resigned.

Mr Brady and Mr Blackburn face disciplinary hearings over their alleged involvement next week.

Following his suspension, Mr Brady complained he had lost day-to-day control of the union because of arguments with the executive.

"I have been the democratically-elected general secretary for eight months. It has been eight months of absolute hell," he said.

Threatened staff

"This is not a battle between left and right - it is a battle between right and wrong."

Mr Brady said the executive had stripped him of power.

He could not even buy a jar of coffee without asking permission, he added.

And the TUC had to intervene to broker a deal between Mr Brady and the GMB union, which represents Aslef employees, after he threatened some head office staff with dismissal.

Branch secretary

A life-long member of the Labour Party, Mr Brady describes himself as a supporter of Prime Minister Tony Blair.

"I would rather see a bad Labour government than a Conservative one," he said.

Mr Brady held a number of posts inside the union, including branch secretary, before being elected onto the Aslef executive in 2003.

He says he has little time to pursue any hobbies or outside interests, preferring to spend as much time as possible with his wife and two daughters, aged five and three, in Southampton.