Flight crew should be paid their average weekly income while on annual leave, not just their basic salary.

In the case of British Airways v Williams, an employment tribunal ruled in favour of BA pilots who argued that they should receive the same pay while on annual leave as they did while working. During periods of annual leave, they were paid only a basic salary with no additional allowances, such as flying pay of £10 for each hour in the air and payments of £2.73 for every hour spent away from their base.

The pilots' individual contracts of employment and collective agreements between BA and the British Air Line Pilots Association do not mention how pay for flight crews on annual leave should be calculated. The Civil Aviation (Working Time) Regulations 2004, also known as the Aviation Regulations, state that airline workers have the right to four weeks' paid annual leave, but do not specify the amount of pay.

The pilots argued that references to paid annual leave in the regulations should be interpreted as being the normal remuneration paid, to leave them in a comparable position to when they are at work.

At a pre-hearing review the tribunal ruled in favour of the pilots because a clause in the Employment Rights Act 1996 states that holiday pay is calculated by reference to a worker's average weekly remuneration. The employer appealed against this, but the Employment Appeals Tribunal (EAT) dismissed the application.

Caroline Carter, partner and head of Ashurst's employment, incentives and pensions group, said: "It is established law that you must look at an employee's earnings during the weeks before annual leave before calculating holiday pay. In this case, the principal piece of legislation that applied to this industry didn't cover the point and so the EAT went to the Employment Rights Act so pilots are treated the same as all other employees."