I am writing an historical mystery book that includes a train derailment. I have loosely used the famous derailment in Henryetta, OK, in 1929, for some of the details. In your opinions, would a train traveling only about 20 mph derail if the switch was cocked? Would it result in the engine and forward passenger cars tipping onto their sides? Or do you think the train would need to be going faster for this type of thing to occur? Thanks for your help.