Derail by Design. A Well Known Problem.

For extra-long freight trains, there is at

• the exclusive use of traction vehicles (single or multiple traction) as traction locomotives at the Trainfront,

• driving through narrow curves,

• Excessive traction from traction vehicles (maximum permissible value: 450 kilonewtons 45 tons),

• Exceeding the permissible limit breaking load of screw couplings (850 kilonewtons 85 tons) or

• the different braking times of the individual freight wagons (train as multi-mass vibrators) triggered by the delayed transmission of the brake command in the main air line of pneumatic brakes

the danger that the longitudinal forces occurring in the train could cause the train or wagon to separate

(fracture or tearing of couplings) and/or derail wagons.

A prerequisite for the safe operation of extra-long freight trains in Germany and Europe is the technical and legally binding implementation of the following solution approaches for the problem described with regard to the longitudinal train dynamics:

Use of central buffer couplings that can transmit higher tensile and compressive forces

Use of an electronic brake control of the freight wagons

Use of several locomotives distributed in the train set (slave), which are radio-controlled by the leading locomotive (master).

Source German language

https://www.forschungsinformationssystem.de/servlet/is/436264/