Why do trains blow their whistles?
There’s a lot more to it than just the obvious “warning people of an approaching train”, especially on the Underground. On that, drivers have to sound their whistles (fed by compressed air) for any number of reasons, amongst which are some of the following: The train is not going to stop (for any number of reasons) at a station at which it would normally do so. The train is ready to leave a depot or siding which is under ‘local’ control. There is a fault on the train and I need a train technician to assist. (They used to be called “Car Examiners”) (At a station) I need assistance from the station staff. (Where there is still a signal box or the area is under ‘local control’ at that time) I have been given a wrong ‘proceed’ signal or I am overdue a proceed signal OR (by pre-arranged whistle signals): This train is going to xxxx (destination or route) as opposed to a different route. [A good example of this used to be at Queens Park (Bakerloo) when the driver of a northbound train approa