Report on overturning accident involving a heavy semi trailer truck on FV 12 by Alteren west of Mo i Rana on 3 October 2013

After a 3.5-hour ferry journey and approx. 50 minutes' drive, the truck arrived at a road section with several curves. The speed limit in the area was signposted as 60 km/h. The truck performed a continuous right, left and right curve. The truck toppled over in the last right curve and ended up off the left side of the road, seen from the driver's direction of travel. Data from the truck's tachograph showed a speed of approx. 63 km/h the last second before the truck overturned. 

The AIBN has uncovered that the accident was caused due to a failure in the interaction between several factors. The design and conditions of the road, the speed of the truck and technical driving factors have all contributed to the accident. The load was homogeneous and, consequently, the centre of gravity relatively high. Furthermore, the investigation has established that this type of load can shift somewhat in certain situations. This applies to cargo inside the cases as well as to the total cargo, which may have had a negative impact on stability.

The AIBN has decided not to make any safety recommendations. However, we refer to the conclusion of the investigation and would like to emphasise that everyone involved in the chain of transportation can help improve safety by learning from the conclusions.