Additional driverless lines currently under construction: London (Jubilee line), Honolulu LRT (new system, 2017).
Some automated metro trains have drivers sitting in the front cabins for safety reasons or to address public concerns. The systems are: Barcelona (Line 2), London (Victoria line), New York (Line L/Canarsie), San Francisco (BART since its start in 1972), Toronto (Scarborough RT), Washington DC.
Under certain weather conditions, wheel slip can be a problem in systems with traditional steel wheels, which is why they still need staff assistance. Staff on board can also check tickets, offer travel advice for passengers or initiate door closure (like at London DLR). Systems with linear induction motors (LIM) or rubber tyres (such as VAL) don't have problems with wheel slip and can be operated completely without staff.
Advantages of driverless metros:
Lower expenditure for staff (staff swallows a significant part of the costs of running a transport system). However, service and security personnel is common in automated systems.
Trains can be shorter and instead run more frequently without increasing expenditure for staff.
Service frequency can easily be adjusted to meet sudden unexpected demands.
Despite common psychological concerns, driverless metros are safer than traditional ones. None of them ever had a serious accident.
Intruder detection systems can be more effective than humans in stopping trains if someone is on the tracks.
Financial savings in both energy and wear-and-tear costs because trains are driven to an optimum specification.
Train turnover time at terminals can be extremely short (train goes into the holding track and returns immediately), reducing the number of train sets needed for operation.
Despite proven safeness of automated systems, some passengers might still have safety concerns or be afraid of trains that seem to run by themselves (despite the fact that elevators are driverless for decades).
Conversion of traditional metros into driverless ones puts train drivers out of work, if they cannot be retrained to work as service or security personnel.
Reversing time of automated trains can be as short as a few seconds. Photo: Lille's VAL.
Platform Screen Doors
Driverless lines are often equipped with platform screen doors. Photo: Paris's line 14.