BA's retirement policy imposed a retirement age of 55, which Cross and several colleagues challenged.
Some brought unfair dismissal claims against the airline, alleging they should be subject to a retirement age of 60 applied by their previous employer.
The Transfer of Undertaking Regulations (Protection of Employment) Regulations 1981 (TUPE) had not been considered at the time they transferred, but the employees alleged they did apply and that, by imposing an earlier retirement age, BA had unfairly dismissed them.
Three other employees claimed under the Sex Discrimination Act 1975, challenging a special exception that BA applied to staff employed pre-1971.
Prior to 1971, male employees had a compulsory retirement age of 60, and female employees, 55.
BA had allowed those male staff to stay in work until the age of 60 - an exception that was later extended to female staff engaged pre-1971.
Although BA staff were mainly female, the majority of pre-1971 employees were male. On that basis, it was claimed the exception was indirectly discriminatory and could not be justified.
All of the claims were dismissed by the employment tribunal and again on appeal.
The Employment Appeal Tribunal (EAT) found that, although TUPE applied and the contractual retirement age for Cross and his colleagues had been 60, 55 was the age that had been consistently applied by BA for years and was the applicable 'normal retirement age'.
The EAT also found that there was indirect sex discrimination but it was justified.