Report on derailment at Loenga station 14 April 2014
Railway report 2018/03
At 04:15 on Friday 14 April 2017, one wagon of a freight train derailed on track 3 at Loenga station on the Hovedbanen line.
At 04:15 on Friday 14 April 2017, one wagon of a freight train derailed on track 3 at Loenga station on the Hovedbanen line. The wagon was number 12 in the train, and it derailed to the right in the direction of travel. The derailed wagon continued for approximately 400 metres before it hit a structure supporting the overhead contact line, and pulled down the contact line. The train stopped when it lost traction power. The wagon came to rest against one of the pillars of Geita bridge, without causing any structural damage to the bridge. Damage was registered to sleepers, a point machine and the support structure. The wagon was so damaged that it was not considered worth the expense to repair it.
The investigation found a track fault in the form of twist at the derailment site. The maximum twist found was 33.20 mm over a 9-metre measurement basis, and 15 mm over a 2-metre measurement basis. This exceeds the action limit set by Bane NOR SF in its technical regulations. When performing measurements on tracks not under load, this shall be considered a limit requiring immediate action.
Bane NOR SF’s project, the Follo line, had performed work on the site prior to the derailment. A track fault was identified during this work. Attempts were made to repair it after the work was completed. The track was reopened for traffic despite the fact that there was still a track fault. The Accident Investigation Board Norway (AIBN) is of the view that the track should not have been reopened to traffic until the fault had been repaired.
An inspection of the derailed wagon on the day of the accident found that the rear coupler was fully tightened. The coupler had bounced off the towing hook connecting it to the next wagon without causing visible damage to the towing hook or coupler.
In the AIBN’s view, the most important causal factor for the derailment was that the track was opened to traffic with a twist exceeding the action limit at the derailment site.
The AIBN submits a safety recommendation to Bane NOR SF as a result of the accident. It concerns follow-up after track corrections have been performed.
Photo: AIBN
Safety recommendation
Safety recommendation JB No 2018/06T
On 14 April 2017, Green Cargo AB’s freight train 45930 derailed on track 3 at Loenga station on the Hovedbanen line. A track fault exceeding the permitted limit value for twist was measured at the derailment site. Excavation work was carried out at the site 12 days before the derailment. The track fault was identified and Bane NOR made two attempts to correct it after the work was completed, but it nonetheless exacerbated up until the time of the derailment.
The Accident Investigation Board Norway recommends that the Norwegian Railway Authority request Bane NOR SF to review and improve the procedures for follow-up after track corrections.
Facts
| Location | Loenga station |
| Occurrence date | 14.04.2017 |
| Train No | 45930 |
| Type of Transportation | Freight train |
| Type of occurrence | Derailment |
| Rolling Stock | Freight wagon, Locomotive |