Becky Kwan Siu-wa, chairwoman of the airline's Flight Attendants Union, is seeking legal advice and stressed that eligible crew members must carefully consider their circumstances before agreeing.

'They won't be able to pursue back pay if they discover later on that they are entitled to it. They have to accept anything the company gives them,' Ms Kwan said. 'Cabin crew are giving up control of their life.'

Union and airline management representatives met yesterday to discuss the scheme, but made no headway.

A High Court ruling last year awarding roughly $280 million in back wages to 3,400 Cathay flight attendants was paid up last April, but Ms Kwan said there were still some individual cases of unsettled claims.

'This is a very one-sided scheme. Everything in the agreement is determined by the company at its sole discretion,' she added.

Ms Kwan also accused the airline of age discrimination by unfairly targeting senior cabin crew.

'We feel Cathay is trying to get in before there is age discrimination legislation,' she said.

'This scheme will give us more leeway to lobby the government for such legislation.'

The government does not favour legislating against age discrimination, which it seeks to tackle through education.

Cathay's scheme is only open to Hong Kong-based cabin crew who joined the In-flight Services Department before December 31, 1991. The airline estimates more than 80 per cent of these crew members are eligible to receive an incentive payment of between 10 and 17 months of their monthly salary on top of their standard retirement benefits. The deadline for applications is 5pm on June 9.

An airline spokeswoman said cabin crew were still evaluating the scheme, which was only announced a week ago.