Report on run-off-the-road accident on fv. 651, Svineroivegen near Rjukan, Tinn municipality on 2 September 2018

Road traffic report 2019/06 eng

English translation now available. On 2 September 2018, a Cadillac 1959 model drove off the road on its way down from Gaustatoppen towards Rjukan. The car drove off the road in the last hairpin bend before Rjukan and all five occupants of the car died as a result of the powerful clash with the rock cutting. The AIBN believes that the combination of prolonged use of the service brake and inadequate maintenance of the brakes contributed to the car losing part of the braking effect somewhere between the last two hairpin bends on the way down from Gaustatoppen towards Rjukan. The car was first registered before 1960 and thus exempted from periodic vehicle inspection requirements. The AIBN's assessment is that a technical inspection of the brakes would have revealed that the brakes were inadequately maintained. The car was not equipped with seat belts, nor was this required in this vehicle. The AIBN's investigation has shown that seat belts could have reduced the scope of injury in this accident.

The investigation has shown that the brakes were gradually weakened and that the car most likely lost almost all braking effect on the last stretch of the road down to the site of the accident. The reduced braking power of the car was the result of prolonged use of the service brakes in combination with high wear on several components of the braking system. The car therefore entered the final hairpin bend at too high a speed to make the turn and collided with the rock face in the rock cutting.

The AIBN's investigation has shown that the brakes of the accident car were poorly maintained and the brakes on the right front wheel were worn out. The brake fluid was clearly contaminated and had a high water content and low boiling point. This also contributes to braking failure under high loads.

The accident car was equipped with automatic transmission, and the gear selector was in the "drive" position when the car was examined after the accident. Seen in conjunction with other findings, this indicates that the driver did not use the gears to brake the car, but used the service brakes on the long, steep descent towards Rjukan.

The road side terrain was designed in such a way that there was no possibility of driving off the road to reduce speed without risking significant damage to both car and passengers.

The AIBN submits two safety recommendation following this investigation.

Safety recommendation

Safety recommendation ROAD No 2019/17T

The investigation into the run-off-the-road accident at Rjukan on 2 September 2018 found that the car's brakes were not adequately maintained. Brake defects was one of several factors that contributed to the accident. No requirements apply for follow-up of the vehicle’s technical condition other than the owner’s own responsibility. The investigation has identified a need for a barrier to identify safety-critical technical defects in older vehicles.

The Accident Investigation Board Norway recommends that the Ministry of Transport, in cooperation with special interest organisations for older vehicles, review the regulatory framework governing the follow-up of such vehicles’ technical condition.

Safety recommendation ROAD No 2019/18T

The investigation into the run-off-the-road accident at Rjukan on 2 September 2018 found that the quality of the car’s brake fluid had deteriorated. At present, periodic roadworthiness tests do not include testing the brake fluid’s boiling point. The quality of brake fluid deteriorates over time and is crucial for the car’s brakes to function in all situations. In the Accident Investigation Board Norway’s assessment, boiling point testing should be included in the inspection of brakes.

The Accident Investigation Board Norway recommends that the Norwegian Public Roads Administration consider including control of the brake fluid’s boiling point in the inspection instructions for periodic roadworthiness tests.

Facts

Location Fv 651 Rjukan, Telemark county
Occurrence date 02.09.2018
Accident type Run-off-the-road accident
Road class County road
County Telemark
Police Disctrict Telemark
Vehicle type Passenger car
Type of Transportation Private transport
Road region Southern Region
Accident category Annen ulykke