Disruption expected on railway services due to signalling fault between Haywards Heath and Three Bridges

Train journeys have been delayed by up to half an hour, and delays are expected to continue until the end of the day.

"Southern, Thameslink and Gatwick Express services are being severely disrupted when travelling between the Gatwick Airport / Three Bridges area and Haywards Heath,” a statement issued by Southern Railway reads.

“At the moment, this is directly affecting the southbound route towards Brighton and the South Coast, but a large number of London-bound trains will also be affected in reaction.”

Explaining the root cause of the issue, a spokesperson for the railway company added:

"Following investigations into a repeated signalling issue at Balcombe, Network Rail staff have determined that they will need to carry out overnight works to rectify the issue. This means disruption is expected until end of service.

“The required work involves changing defective insulation between track circuits, which are electrical devices which detect and monitor the passage of trains, as part of the signalling system. The railway is divided into different track circuit sections, in order to allow multiple trains to run on each route at a time. When the insulation fails, the signalling system cannot determine which section of track is being occupied by a train, so drivers have to stop and gain verbal permission to continue, usually at much slower speeds. This leads to substantial congestion on a busy route like the Brighton Mainline.”