Report on fire in locomotive at Sarpsborg station on the Østfold Line on 2 October 2021

The engine failure occurred due to a crack in the bandage at the outer end of the rotor. As the bandage started to come loose, it got caught in the coils or poles of the stator. This led to the rotor starting to screw outwards, which in turn led to a crack in the end cover. As the rotor unscrewed and the end cover gave way, the speed sensor cogwheel, mounted at the end of the rotor, came into contact with the inside of one of the bogie wheels. In turn, this mechanical contact led to overheating and spark formation, which ignited the cabling and components in cabinet S8 in the engine room through a grate on the underside of the cabinet. The heat and fire caused a great deal of damage to the inside of the S8 cabinet. 

The NSIA has not found out what caused the crack in the rotor bandage. It has not been possible to determine whether this was due to an electrical fault during operation, or whether there was a foreign body or a mechanical crack in the bandage. Examinations of the engine showed that bearing surfaces in the engine were intact and undamaged.

After the fire was extinguished, the locomotive was inspected for damage on site. In consultation with CargoNet’s technical department in Oslo, the driver decided that the locomotive could be transported inactive in the train back to Oslo. The engine failure and the fire had caused damage to the wheel and parking brake of the failed engine, which was not detected. On their way back to Oslo, the driver stopped the train at Fredrikstad and Moss to check for further fire or other damage. No damage was found at these stops. The NSIA believes it was difficult to detect the damage since the engine and most of the mechanical damage were on the inside of the bogie frame. Driving the locomotive any further could have led to derailment. 

Due to the age of the locomotive, no systems were fitted to detect or prevent this type of fire. When running in multiple from another locomotive, the amount of information the driver receives from the rearmost locomotive is limited. This complicates the process of finding and correcting errors, among other things. Nor are there any systems in place to detect, extinguish or prevent this type of fire. The NSIA believes it is likely that an incipient fire would have been detected earlier and could thus have been stopped if the train had been operated from the damaged locomotive.

EL16 is an older locomotive model that is being replaced by newer models over time. Since the direct cause of the engine failure is not known, and due to the design and age of the vehicle, the NSIA does not propose any safety recommendations after the accident.

Photo: CargoNet AS

Photo: NSIA

Published 02.12.2022