The tunnel is signalled only for CBTC. The outer ends of the line have only the old fixed-block signalling. The section from Westall in the south east to (eventually) Sunshine in the north has both. There is a dedicated model of train, the HCMT, which is fitted with the CBTC and is the only type that can run through the tunnel during normal operation. When an HCMT passes Westall heading towards the tunnel, the lamps on the fixed block signalling ahead of it go out. When a diesel regional train has HCMTs ahead of it on the next fixed block, it will see the lamps lit for Stop.
Trains runnin have been running this way in normal passenger service for months now, though I think it’s only in the last few weeks they’ve been testing it with HCMTs entering the tunnel at Hawksburn with diesels behind them instead going to South Yarra. (Currently, the trains with actual passengers take the South Yarra route at that junction.)
The HCMTs run only on this line, from Sunbury to East Pakenham/Cranbourne. They have their own new depot at East Pakenham so they don’t have to go elsewhere for stabling and maintenance. And they probably can’t; just for them to go through the City Loop as is temporarily required that tunnel had to be resignalled (the old location wasn’t visible from the cab.)
They did run an old Comeng train through the Metro Tunnel, without any signalling, to test clearance for a track maintenance train.
Trains runnin have been running this way in normal passenger service for months now, though I think it’s only in the last few weeks they’ve been testing it with HCMTs entering the tunnel at Hawksburn with diesels behind them instead going to South Yarra. (Currently, the trains with actual passengers take the South Yarra route at that junction.)
The HCMTs run only on this line, from Sunbury to East Pakenham/Cranbourne. They have their own new depot at East Pakenham so they don’t have to go elsewhere for stabling and maintenance. And they probably can’t; just for them to go through the City Loop as is temporarily required that tunnel had to be resignalled (the old location wasn’t visible from the cab.)
They did run an old Comeng train through the Metro Tunnel, without any signalling, to test clearance for a track maintenance train.