ARK were contracted to provide a complete signalling design solution from concept through to commissioning to facilitate the introduction of the longer ‘S’ Stock trains. The solution was required to maintain the existing performance capability whilst not increasing the workload for the local signalling staff.

These requirements led to the implementation of a complex signalling design solution with a combination of mechanical and relay interlocking technologies. The project was successfully delivered to the agreed costs and timescales. London Underground amongst others have recognised this project as one of the most successful complex LU signalling projects in recent history.