Your article "In some Maryland railroad towns, crude oil is an open secret" (Dec. 25) prompted me to comment on where a risk of disaster might be. We can learn from the wreck of the fully loaded coal train in Ellicott City a few years ago. As the train enters the curve the locomotive and the first few cars become misaligned with the remainder of the train — in other words they begin to follow a path to the side not matched by the rest of the train. As the fully loaded coal train enters the curve the emergency brakes are applied by compressed air from the locomotive to the cars. What actually happens is that the brakes are applied to the locomotive and progressively to the leading cars, the major part of the train remaining unbraked. Because of the misalignment of the front of the train on the curve the weight of the unbraked part of the train pushes the leading braked cars and the locomotive aside and off the track, jackknifing.
The pragmatic solution to this type of problem is to make sure that all heavily loaded mineral trains approaching curves do so at speeds safe enough to prevent them from jackknifing.
Peter Dolby