An embattled British Airways is due in court in the latest stage of a dispute over holiday pay for its pilots.

Already battling cabin crew in a separate case, the British flag-carrier has been taken to the Supreme Court in London by the British Airline Pilots Association (Balpa) in an attempt to secure an increase in holiday pay for members.

Balpa argues holiday pay for pilots should be based on what they earn, rather than on just their basic pay without allowances.

Pilots at the airline receive a basic salary, but this is supplemented by allowances for everything from simple flying time, to flying at night and time away from base. British Airways presently uses just the basic salary to calculate holiday pay, with Balpa arguing it should be based on total pay, including these allowances.

Balpa’s case is supported by Working Time Regulations, which set out how holiday pay should be calculated; stating holiday pay should be an average of the last 12 weeks’ pay.

However, BA argues the legislation does not apply to the airline sector, which is governed by separate Civil Aviation Working Time Regulations.

Balpa has also launched legal action against Virgin, BMI, Easyjet and Cityflyer.

Balpa general secretary Jim McAuslan explained: “We are making the case that in the UK, the civil aviation regulations should be amended to give workers in our industry the same right to proper holiday pay that everyone else gets.”

As many as 12,000 pilots and 30,000 cabin crew at BA could be affected by the ruling, with holiday pay potentially increasing by up to £600. Any deicison against BA could cose the airline up to £9 million annually.

Ahead of the case British Airways said: “We were pleased with the Court of Appeal decision in favour of British Airways last year.

“We have always been of the view that our holiday pay arrangements are generous and comply with legislative requirements.

“We will continue to resist the claim strongly.”

Cabin crew are presently embroiled in a separate dispute with the airline, voting to pursue a course of industrial action earlier this week. Strikes are now expected in the coming weeks, following a disagreement over contractal changes imposed by BA.