Prior to the 1986 electrification and resignalling, most of the Hastings line south of Tunbridge Wells was semaphore signalled with absolute block. However, between Tunbridge Wells and Wadhurst, there was continuous 3-aspect colour-light signalling and - I believe - track circuit block working between Grove Junction and Wadhurst signal boxes. Does anyone know when this was put in, and whether the box at Frant was abolished at the same time?
I have always assumed that it was there to facilitate the original DEMU service, where trains divided at Tunbridge Wells with the front unit running fast to Battle and St Leonard's, and the rear unit calling at all stations. The 3-aspect signalling would have allowed the rear unit to leave Tunbridge Wells straight after the front unit. By the time it reached the end of the 3-aspect signalling at Wadhurst, the front unit would have cleared the section to Stonegate or Etchingham. In the up direction, the stopper left Hastings first, and the 3-aspect signalling from Wadurst inwards would have allowed the fast to 'close up' on it, and arrive at Tunbridge Wells right after it.
I have always assumed that it was there to facilitate the original DEMU service, where trains divided at Tunbridge Wells with the front unit running fast to Battle and St Leonard's, and the rear unit calling at all stations. The 3-aspect signalling would have allowed the rear unit to leave Tunbridge Wells straight after the front unit. By the time it reached the end of the 3-aspect signalling at Wadhurst, the front unit would have cleared the section to Stonegate or Etchingham. In the up direction, the stopper left Hastings first, and the 3-aspect signalling from Wadurst inwards would have allowed the fast to 'close up' on it, and arrive at Tunbridge Wells right after it.
