C10/2004R Derailment of two freight cars in Kouvola on 30 July, 2004
On Friday July 30, 2004 at 3.12 pm, two wagons belonging to a freight train were derailed at the western end of the Kouvola passenger traffic railway yard. The freight train was travelling from the direction of Lahti. Besides the derailed wagons, three points and 60 metres of track were damaged. The accident prevented all traffic from Kouvola towards Lahti and Mikkeli until 5.45 pm. Repairing the damage caused by the accident cost over € 60,000.
The accident was caused by longitudinal forces, created by the braking freight train, which lightened the vertical load of the rear bogie of the Russian wagon situated on top of a discontinuity point on the running surface of the crossover. In addition, wear on the discontinuity points on the running surface of the crossover, the heavy brakeless wagon behind the light wagons and the train’s uneven weight distribution contributed to the derailment.
Because this type of derailment is statistically rare and since locomotive engineer training covers longitudinal forces, the Accident Investigation Board of Finland does not make any new recommendations, instead issuing a reminder that locomotive engineer training should emphasise risk of derailment at curves and points.