That reminds me of a terrible crash on the old Vienna subway system.
In the late 1970s the signalling system was ancient (1924-25) and malfunctions (mainly permanent red i.e. "STOP") were nothing unusual. So, the ingenious management devised a way to circumvent that... after stopping for a defined time at the red signal, the motorman was allowed to enter the next block at 15km/h (given the extremely dim headlights of the cars built in the 1950s that was pretty hefty inside a tunnel or open cut).
After a soccer match, "fans" started to wreak havoc on one train, unscrewing the light bulbs. Supposedly the tail light was on the same series as the inside light... (those old cars had 95V incandescent bulbs wired in series to the 750V DC traction power). So, the rear of the train was dark. Before descending at the Meidling Hauptstraße stop they pulled the passenger emergency brake handle. In spite of this, the train pulled out of the station, coming to a halt on the open tracks.
The motorman of the next train waited at the red signal, then continued at 15km/h (roughly 10 mph). Suddenly he noticed the block signal ahead of him being green and accelerated to the full speed of 40km/h. However, he failed to notice the unlit train between himself and the green signal, crashing into it at full speed... luckily no one died, the second motorman only had a broken arm (pretty miraculous for such a crash).
Brake failures were pretty common back then too - the trains had only pneumatic brakes operating by cast iron pads. Those pads had to be readjusted frequently (several times per day I guess) due to abrasion and the pneumatic system was old and undersized - the cars had been built in 1954- 1961 using most of the pneumatic parts of the older 1924-1929 cars but adding a second brake system, pneumatic doors and some other systems to the old compressors.
