Why do some British trains still rely on old levers?

fail-safe mechanical interlocks

They still use old levers because the mechanical interlocks are fail-safe and incredibly reliable. Replacing them would cost hundreds of millions and cause massive disruption, with no guarantee of improved capacity.

• ⚙️ The Victorian-era mechanical interlocks physically prevent signallers from making dangerous moves.
• 💰 Upgrading to modern systems would cost hundreds of millions and require extensive line closures.
• 🚦 Red lights on the back of trains are proof that the entire train has passed a signal.
• ⏱️ Learning the basics of signalling takes half a day, but full qualification takes about ten weeks.

A man stands in front of a wall of old train signal levers, looking at the camera.