Our immediate goal is to restore United's financial stability

John Creighton, new UAL chairman & chief executive

Mr Goodwin said he was resigning - after 34 years with the firm - because "it is the right time for a new leader to guide the company through the challenges that lie ahead".

The board of the airline's parent company, UAL, said it had elected John Creighton to replace Mr Goodwin as its chairman and chief executive by an unanimous vote.

Shares tumble

"Our immediate goal is to restore United's financial stability," said Mr Creighton.

"We intend to work hand-in-hand with our employees and unions to accomplish this task by developing innovative solutions to the issues we collectively face".

Shares in UAL plummeted to a 14-year low of $13.93 as Wall Street closed for the weekend on Friday 26 October.

Haemorrhaging money

UAL is expected to report operating losses of up to $600m for the three months from July to September on 1 November.

Clearly this bleeding has to be stopped - and soon - or United will perish sometime next year

James Goodwin, United Airlines

In his controversial letter, Mr Goodwin acknowledged that the airline's costs were already exceeding revenues before the 11 September attacks.

"Today, the situation is exacerbated with costs exceeding revenues at four times the pre-September 11 rate," he warned.

"Today, we are literally haemorrhaging money. Clearly this bleeding has to be stopped - and soon - or United will perish sometime next year."