Accident Investigation Board Norway
The Accident Investigation Board Norway (AIBN) is required to be competent, innovative, credible and compassionate. For more than 20 years, AIBN has been a permanent, independent body of inquiry for transport accidents. AIBN started out investigating aviation accidents in 1989, and has seen its area of authority expand to include railway, road traffic and shipping accidents.
The investigation has as its goal clarification of the sequence of events and causes, as well as discussing other significant conditions that could prevent rail accidents and serious rail incidents in order to improve railway safety. The investigation does not apportion blame and liability.
The AIBN Reports are published on the AIBN web site. The majority of the railway reports have been added to the Aitken & Partners web site for convenient searching. Most of the reports are in Norwegian but all the reports published on this site have English summaries.
Documents
Failure of the TETRA System for Oslo Underground Railway - 8 July 2004
Accident Investigation Board, Norwzay - Report 6/2005
On Thursday July 8 2004 at 0650 am the train controller at the Oslo underground railway discovered that the communication system between the train controller and the train guard was down. It proved impossible to establish contact with any trains, over ground or underground. The train controller did not get any warning or error report on the problem. The train controller consequently contacted Tele Denmark, who is responsible for maintaining the TETRA communication system, for information on the cause of the breakdown and when the system could be expected back in service. They estimated it would take one hour or more. To maintain traffic in the mean time, the train controller tried to use the old VHF system, which still had channel 6 and 8 available. Unfortunately, he was able establish contact with only some of the trains. The VHF system is no longer in use, and the train guards; therefore, do not receive any training on the use of the system. As a second possibility, the train controller tried to obtain the mobile telephone numbers to all train guards that did not respond to VHF calls. Personnel were also being sent to Majorstuen and Tøyen stations to inform the train guards about the communication problems and to ask them to try the VHF system.
The TETRA system went down because of a short circuit in one of the main switchboards in TDC Norway’s main TETRA central in Oslo. This had as a result that most of TDC Norway’s network was out of service from about 0630 am to about 1030 am. When the error occurred at 0130am, TDC Norway’s emergency diesel generator started as expected, but because of a technical fault the power supply to the system rectifiers stopped. The rectifiers started to use power from the UPS batteries. These got run down by 0630 am and the system was shut down.
To maintain personnel safety and security the personnel safety representative chose to stop all underground trains until the communication system was back in service. At 0851am the train controller made a broadcast on the VHF system that all traffic was to be stopped until further notice. In addition, personnel on Majorstuen and Tøyen stations informed the train guards directly that the traffic was stopped. All underground trains were stopped at the first station and held there until the communication system was back in service at about 1030am. At the time of the incident there were in total 118 carriages in traffic with approximately 5000 travellers.
Thus, this single-point failure was capable of making inoperative the whole communication system rendering all contingency measures useless.
Train service on the underground is normally controlled by signal systems and is only occasionally based on verbal orders. When the communication system is down, train service shall be performed with trains at “station distance”. This was not ensured in this case, primarily because this was an unknown procedure to some of the train controllers. The Accident Investigation Board has, during the course of its investigation, not revealed procedures that describe how train guards shall deal with an incident that demands evacuation of a train between stations within the tunnel system, in a situation where the communication system between the train controller and the train guard is for some reason made inoperative.
The Accident Investigation Board has been informed that new rules and regulations has been effectuated to deal with a similar situation to the one described in this report. This includes procedures for handling train service run at “station distance”, procedures and routines for evacuation between stations in tunnels and the demand for communication. On this basis, the Accident Investigation Board has decided not to issue any safety recommendations.
Locomotive Explosion in Oslo Tunnel near National Theatre Station - 9 August 2002
Accident Investigation Board Norway Report JB RAP: 5/2004
A cargo train with number 5807 with a Norwegian produced electric locomotive of type EL 14.2180, operated by CargoNet AS, experienced on 9. August 2002 at 2125 hrs, an explosion while driving in the tunnel under Oslo city, southbound towards Drammen/Kristiansand.
This serious railway incident occurred 100 meters before the train entered the National Theatre railway station in the tunnel and caused damage in the locomotive engine room. The blast from the explosion caused the blast deflection doors to be pushed out and created a fragmentation effect out through the exterior of the locomotive.
The decision to investigate this serious incident was based on the risk potential of exposure of the large numbers of passengers waiting for trains at the various platforms of the station in the tunnel, to smoke and fragments from the explosion. No persons were hurt by this incident and only material damage to the locomotive occurred.
The investigation revealed that the explosion had taken place inside the locomotive, which was produced during 1968 – 1973, in the throttle control assembly located in the locomotive engine room for regulating the amount of electric current needed for propulsion of the train. The function of this assembly was to regulate the electric current used directly for propulsion of the locomotive through 32 steps, from idle to full traction effect. The incident took place while the power setting was at step 2, nearly idle and the train had a speed of 39 km/h. This assembly constitutes a vessel with a volume of approximately 50 dm3, containing 32 mechanical contactors for high voltage electrical current, submerged in insulating oil.
The investigation has found that this type of locomotive has experienced in its operation history, several explosions and pressure problems with the vessel, causing the previous operator to perform several modifications to the vessel containing the throttle controller assembly by installing pressure relief devices.
Collision between freight train 5512 and local train 223 at Stryken - 12 February 2009
Accident Investigation Board Norway - Report JB 2010/01
On February the 12th 2009 freight train 5512 was going into track 2 on Stryken station to cross local train 233 running in opposite direction in track 1.
Control point 2 at Stryken station was out of control, and the traffic controller was not able to set the entry signal B to” line-clear”. The driver of the freight train was given order by phone that the line was clear into track 2 at Stryken station.
The freight train was 13 meters longer than track 2 at Stryken station. After the locomotive had reached the clearing position in track 2 and stopped, the end-runner was still on the connection line from track 1 to track 2. Due to snow and ice on the tracks the connection line was indicated as clear. The point was set back to track 1, and the exit signal set to “line-clear” for local train 233.
The driver of local train 233 noticed that the freight train end-runner was in conflict with his route, and realized that it was not enough space to drive out of the station. The driver of train 233 notified the traffic controller about the situation. The traffic controller immediately set the signal to stop, and performed an emergency release of the train route.
Although there were no injuries or damages as a result of this incident the Accident Investigation Board Norway chose to investigate this incident. There is a risk of accidents when an occupied track is not indicated as occupied.
The Accident Investigation Board Norway submits one safety recommendation:
- The Norwegian National Rail Administration reviews the rules and winter preparedness regarding routines for notifying the traffic controller about tracks which has not been cleared for snow to be closed for crossing of trains.
Derailment at Skotterud Station - 1 October 2010
Accident Investigation Board Norway - Report JB 2011/08
Friday October 1. 2010 passenger train 55/846 was traveling from Oslo to Stockholm. When the train passed through track 1 at Skotterud station on the Kongsvinger line, the first wheel set on the rear bogie on the first wagon derailed.
The train was driving at 95 km/h when it derailed. The first wagon turned left in the rear end and hit the platform edge, a relay kiosk was crushed, demolished parts of the barriers on a railroad crossing and broke a pole to the overhead power supply system. The wagon jumped up in the rear end and lost the bogie when it hit the level crossing situated in the end of the station. The wagon then turned out right and turned over. 36 persons were injured.
The direct cause to the accident was that the right wheel on the first axel of the rear bogie on the first wagon had a breakage. The bogie lost its steering and it started to transverse.
In this investigation the Accident Investigation Board has focused its work on three subjects:
- The wheel breakage
- The survivability aspect at this kind of derailments
- The rescue work
The Accident Investigation Board Norway proposes two safety recommendations as a result of the investigation. These include to advice the Norwegian Railway Authority (NSA) to ensure that railway companies that are operating in Norway have safety management systems that catches this kind of error in an early stage. There should be done a going through concerning the routines for the communication between the traffic controller and the rescue personnel considering ensuring fast and efficient communication.
Accident with Freight car set that rolled uncontrolledly from Alnabru to Sydhavna on 24 March 2010
Accident Investigation Board Norway - Report JB 2011/03
On Wednesday, 24 March 2010, a freight car set consisting of empty container freight cars rolled uncontrolledly from Alnabru shunting yard, down to Loenga and into the sea at Sydhavna in the Port of Oslo. The AIBN has carried out a safety inquiry into the accident and is submitting a total of seven safety recommendations based on this.
The accident was triggered by a misunderstanding between the local traffic controller and the shunter about which shunting route to set, and the result was that the freight car set started rolling from an arrival track (A track) at Alnabru. When the shunter added an extra freight car to the freight car set, the local traffic controller was convinced that the freight car set was being shunted for loading.
The result of this was that the local traffic controller released the mechanical brake that held the freight car set in place on the A track. The shunter had not intended to move the freight car set and had uncoupled the shunting engine.
There were no shared mental models, standard phrases or readback-hearback systems in place to prevent misunderstandings of communication between the local traffic controller and shunting personnel at Alnabru. Furthermore, two provisions which could potentially have stopped that particular chain of events were 'dormant' and not known to the operating personnel.
When it became clear that the freight car set had started rolling and was not coupled to a locomotive, it had already moved to track G4. It was not possible to stop the freight car set by setting a diversion route before it left Alnabru. Nor were there any barriers on the freight train track between Alnabru and Loenga/Sydhavna which could stop the freight car set in a controlled way. The accident reflects a breach of the ‘no single point of failure’ principle which dictates that railway operations shall be planned, organised and performed in such a way that a single failure does not lead to loss of human life or serious personal injury.
In the AIBN's view, the basic premise that allowed the accident to happen was the fact that Alnabru was being used in a manner for which it was not originally intended. This was a consequence of structural changes and increased rail freight traffic, combined with a lack of remodelling and development work on the infrastructure to reflect this development.
A focus on efficiency and productivity on worn-out, outdated infrastructure, and an insufficient focus on updating safe work practices had reduced safety margins. Political priorities and the NNRA's own prioritising of freight traffic had played their part in this lack of alteration or development.
The investigation showed that both the NNRA and CargoNet AS have consistently failed to handle safety-critical information in a systematic way. There was not enough of a culture of reporting incidents, governing documents were inadequately distributed and implemented, risk assessments were fragmented and inadequate, and the system for collecting and handling safety-critical information from the operational parts of the organisations was deficient. The result of this was that, until the time of the accident, the NNRA and CargoNet AS were both unaware that Alnabru had fundamental faults and deficiencies in terms of operational and technical safety barriers.
The NNRA had not adequately followed up its responsibilities as Principal Enterprise for infrastructure management, for instance through carrying our overall risk assessments. In a complex system like Alnabru, it is especially important that all the organisations involved work together to set up barriers against single failures. This does not seem to have been properly addressed. Alnabru lacked an overall safety management system which would pick up the risks that were a consequence of the many changes that had taken place over time.
The AIBN's investigation has shown that Alnabru does not seem to have been sufficiently 'seen' by the Norwegian Railway Authority (NRA). Even if the responsibility for safety lies with the railway undertakings, the AIBN would nevertheless like to see the supervisory authority playing a more proactive role in overseeing how the undertakings address this responsibility. This is particularly important as regards control of the risk of major accidents in complex areas.
Fire incidents in three Siemens MX3000 Metro Trains
Accident Investigation Board Norway - Report JB 2011/09
After three fire incidents in the new Siemens MX-3000 metro trains the Accident Investigation Board Norway (AIBN) effectuated an investigation. The fire incidents happened between October 2009 and January 2010. One incident occurred in the tunnel at the joint section, and the two other incidents occurred on open line.
In the period after the first preliminary report was published there have been another three fire incidents in the current collector on the MX-3000. One incident happened in the tunnel at the joint section between the stations Tøyen and Grønland, the second incident happened at Manglerud station and the third incident happened at Østhorn station. These incidents have been included in this final report.
Two of the fire incidents happened in the tunnel at the joint section.
The AIBN has performed technical examinations, held meetings with Oslo T-banedrift AS, the workshop at Ryen, Oslo Vognselskap AS (OVS) and representatives from Siemens. There has also been a meeting where all parties have been represented.
The AIBN report includes a comprehensive report in English from Sintef into the rapid rate of degradation of the insulators used in the trains.
Technical Investigation into the April 5th 2004 Railway Accident at Saint-Romain-en-Gier, France
The accident was due to track works between the cities of Rive-de-Giers and Givors, in a railway section equipped with reverse signalling. The works carried out on the night of the 4th to 5th of April took longer than expected, and consequently the works trains were behind schedule on their return journey. The ballast works train return journey conflicted with the first commercial morning run between Lyon and Saint-Etienne. Due to a series of errors, these two trains were running in opposite directions but moving towards each other on the same track and a head-on collision could not be avoided. Two people were injured and there was considerable damage done to rolling stock.
The analysis of this operating accident concluded to no fault due to either the technology (material means) or the procedures as such ; the accident was due to a series of human errors starting with the planning of the works, all the way through to the carrying out of the works. Also, each department involved in the various operations contributed its own share of errors.
The works instruction sheet drawn up in advance to identify all conditions under which the project would be carried out, was not specific enough as to works train movements and the need to set the direction of the train route ; signalling for the egress route was not set in the correct direction.
Concerning driving the works train and determining the boundaries of its scope of action, failings in reading certain markers and signals (particularly those turned off at night) prevented the two converging trains from stopping on time.
Both the night and morning traffic agents failed to share sufficient information with each other, to the extent that the morning traffic agent had an erroneous mental picture of the situation (in fact the picture of previous works sessions) and unduly set a route by manoeuvring buttons through attention support devices.
Also, the investigation brought out the fact that the planners from « Operations » and « Rolling Stock » had not indicated on the works instruction sheet that the work site covered two intervals running counter to each other. They had also failed to indicate the direction in which traffic was to run inside these intervals.
In order to improve the level of safety and successfully carry out such a project, the following recommendations were made at the end of the investigation :
Improve training and awareness of all infrastructure departments - operations and rolling stock - to the problems involved when lines equipped with reverse signalling.
Prior to any job, improve the description of all works train movements, so that field operators will have a set of clear and unambiguous instructions.
Ensure that safety operators have indeed taken the time to study all works programmes beforehand and that they have clearly laid out all their procedures when works begin.
When outside safety operators from a different centre are brought in as reinforcement, it is important that they familiarise themselves with the layout of the area and with the infrastructure they will be using.
Give the works train agents the signalling diagram of the line section where they will be expected to discharge their duties.
In summary, documents given to field agents for the execution of their work should be subject to no interpretation whatsoever. Also, the SNCF’s internal auditing system should focus on highlighting any possible procedural deviation in order to maintain the high level of safety of the railway network.