Plans to introduce new longer carriages on Gatwick Express trains are now under threat because of a union dispute.
The 12-carriage trains are due to be driver-only with no conductor on board, but members of the Associated Society of Locomotive Engineers and Firemen (ASLEF) are now considering industrial action because of safety fears.
Gatwick Express trains are currently 10 carriages long. The first service with the new carriages was due to start at Gatwick on Saturday, but was cancelled and 30 passengers had to transfer to another service.
ASLEF are now balloting members over strike action.They say that longer trains are safer with guards on board overseeing the opening and closing of carriage doors and of the trains leaving platforms.
ASLEF spokesman Marz Colombini said the prime issue was safety, along with the threat to guards’ jobs.
A spokesman for Gatwick Express said: “Everyone knows longer trains are a key part of the solution to improving the rail service for passengers. We urge ASLEF to put passengers first and drive these trains when they come into regular service next week.”
The outcome of the strike ballot is not expected to be known for some weeks.