ADD▸ (Automatic Dropping Device) is only a protection system that hopefully will safeguard the pantograph
if the wires run out. Once activated the Pan will stay down and can only be reset by a
fitter. The roof strike at Blackfriars is a bit of an anomaly as the 319 would have had to be on DC▸ (Direct Current) power to get up that severe incline.
I have seen the procedure on IEP▸ (Intercity Express Program / Project.) trains for changing from AC to Diesil mode. It's a one button job but just relies on the driver's route knowledge and lineside signage.
This sort on mishap will happen from time to time until ERTMS▸ (European Rail Traffic Management System.) is up and running. Then the system will prompt the operator and if necessary stop the train if no action is taken.