Report - Safety Investigation Running away of an SNCB/NMBS train between Landen and Tienen on 18 February 2016

Transcription

1 Investigation Body for Railway Accidents and Incidents Report - Safety Investigation Running away of an SNCB/NMBS train between Landen and Tienen on 18 February 2016 October 2016

2 2 Any use of this restricted report with a different aim than of accident prevention - for example in order to attribute liability - individual or collective blame in particular - would be a complete distortion of the aims of this report, the methods used to assemble it, the selection of facts collected, the nature of questions posed, and the ideas organising it, to which the notion of liability is unknown. The conclusions which could be deduced from this would therefore be abusive in the literal sense of the term. In case of contradiction between certain words and terms, it is necessary to refer to the French version.

3 1. SUMMARY 1.1. BRIEF OVERVIEW On Thursday 18 February 2016, just before Landen station, a driver who had got down onto the tracks to inspect his train, noticed the train starting to move by gravity. The driver did not manage to get back onto the moving train, which ran away for around 12 kilometres until Tienen INVESTIGATION The incident does not meet the definition of serious accident but the IB did decide to open a restricted investigation to determine the reasons that allowed the runaway train to travel for 12km and to check the safety measures taken to avoid further accident CAUSES AND SAFETY RECOMMENDATIONS According to the IB analysis, the incident was an unexpected movement of the train which became a runaway for around twelve kilometres DIRECT CAUSES The direct cause of the running away of the train was the releasing of the brakes following sufficient pressure in the ABP after the driver had closed the pneumatic valve. The elements contributing were: the lever was not in brake or emergency brake position; the parking brake was not engaged during the inspection of the train by the driver; the grade of the track which allowed the train to start moving by gravity; the AM80 did not have a system preventing runaway which could have stopped the train INDIRECT CAUSES Non-compliance with the HLT procedure by the driver for stopping his train while he was inspecting it; the untimely movement of the lever of the pneumatic release valve allowed air to escape from the main reservoir of one of the cars, resulting in a pressure drop in the ABP RECOMMENDATION Various measures have already been taken by the SNCB/NMBS (see chapter 5 of this report). The lever of the pressure valve, which was initially not foreseen, was fitted in the workshop. Although supposedly this was done with the best intentions, this modification has increased the risk for an accidental opening of the tap of the pressure valve. The SNCB/NMBS should evaluate its procedures to ensure that prior to making modifications, the risks created by these modifications, which initially seem insignificant but possibly have an influence on the safety systems (braking system ), are analysed. 3

4 2. BASIC INFORMATION 2.1. LOCATION 2.2. THE FACTS At around 20:35 on 18 February 2016, about 800 metres before Landen station, the driver of train E15440 noticed the pressure dropping in the automatic brake pipe (ABP). 400 metres further on, the train stopped in openline. The train E15440 was an empty passenger train, that had left from Kinkempois and was heading for Leuven station. The driver contacted the breakdown service in Leuven for help and advice. Following various checks and manipulations in the driving cab, the driver informed Traffic Control of the reasons for stopping. He left the driving cab and descended into the tracks to inspect the train. He noticed that the pneumatic release valve was open and he closed it. He climbed into the cab of the second motor coach to check the pressure on a pressure gauge. He climbed down from the train to return to his driving cab from the outside. At that moment, he saw the train start to move by gravity: he tried, in vain, to climb back onto the train. He immediately informed the ROR service in Leuven using his service mobile phone. An exchange of communications followed between the different Infrabel services resulting in the: safe scheduling of a route for the runaway train towards a dead-end track in Tienen station; an attempt to stop the runaway train; safety of railway.traffic and passengers was ensured. At Tienen station, as the runaway train was slowing down, a driver managed to jump into the cab and stop it by engaging the emergency brake VICTIMS AND MATERIAL DAMAGE There were no fatalities. No damage was found to infrastructure or rolling stock. 4

5 2.4. RAILWAY VEHICLES The train E15440 was made up of two motor coaches AM80 (Nos 313 and 415). The AM80 are electric motor coaches made up of 3 bodies/cars. They are equipped with the driving assistance system TBL1+. Driving cab 5

6 2.5. RAILWAY FACILITIES LINE 36 The train E15440 was operating on line 36, a line electrified with 3kV. Between Landen station (altitude: m) and Tienen station (altitude: m), the form of the line was the following: TRAFFIC MANAGEMENT The portion of the line involved in the incident was managed by Block 9 in Leuven PERSONS INVOLVED PERSONNEL FROM THE SNCB/NMBS RAILWAY UNDERTAKING The train driver E15440 The train driver E PERSONNEL FROM THE INFRASTRUCTURE MANAGER INFRABEL Assistant manager for Block 9 in Leuven Dispatcher for Block 9 in Leuven Duty staff in Leuven The ES distributor TC Telm (Technical electro-mechanic) I-AM THIRD PARTY No third party was involved in the incident WEATHER At the time of the incident, the temperature was 4 C. The weather was calm (light breeze) and dry. 6

7 3. ANALYSIS 3.1. CHRONOLOGY OF THE INCIDENT 20:36: The driver of the train E15440 informed TC that he was getting out of the train to inspect it. 20:54: The assistant manager B-TR informed Block 9 in Leuven that the train E15440 was moving driverless towards Ezemaal. Block 9 immediately scheduled a route for this train, ordered opening of the signals in the direction of travel of the runaway train (in this way, the level crossings closed normally and the route to be travelled was locked). He then puts cases from Table 3 on the tracks. 20:55: The train E1518 (Blankenberge - Genk) entered track 603 in Tienen station: it was travelling in the opposite direction to train E :58: The train E3644 (Landen - Gent-Sint-Pieters) travelling in the same direction as the train E15440 entered track 605 in Tienen station. 21:00: TC and Block 9 decided to send the runaway train to the dead-end track 671 in Tienen station. 21:02: The runaway train E15440 passed the unmanned stopping point at Neerwinden. 21:03: The train E3644 being on track 605 that the train E15440 was intended to use, was asked to immediately leave Tienen station. 21:04: The train E3644 left Tienen station in the direction of Vertijk and Leuven. 21:05: It was decided to leave the train E1518 at the station and to evacuate the passengers and personnel to track I and the station buildings in Tienen. 21:07: Electric power supply to track B was cut between Ezemaal and Tienen by the ES distribution board at the request of TC. The route of the train E15440 towards track 671 via track 605 was confirmed. 21:08: The runaway train E15440 passed the unmanned stopping point at Ezemaal. 21:17: The runaway train E15440 entered the points at the entrance to Tienen station. The driver of train E1518, freom track I, saw the train E15440 entering Tienen station at a reduced speed: he decided to try and stop the runaway train. Via the steps and underpasses, he ran to track :18: The runaway train E15440 was in track 605 of Tienen station. TC asked the SOC to follow the train using surveillance cameras. 21:22: While the runaway train E15440 was entering the points on the Leuven side, the driver of train E1518 managed to jump onto the train, go to the driver's cab and engage the emergency brake. 21:27: Confirmation from the driver of train E1518 that he had braked the runaway train. His colleagues then followed the procedure for immobilising the train. 7

8 3.2. AFTER THE INCIDENT: INFRASTRUCTURE 21:30: TC gave authorisation to the ES distribution board to restart electricity supply to track B of line :35: Restarting of operations on a single track (track A) between Vertrijk and Landen. As long as a Telm had not checked the points on track B, TC stopped all train circulation on this track. 21:38: Block 9 called a technical electrician to check the points that the runaway train passed. 22:31: The points 21BR and 22AR from Ezemaal were checked by the Telm and could be travelled in both positions. Single track service (via track A) was restricted between Ezemaal and Vertrijk. 23:01: The points 15R, 13BR and 14AR were checked by the Telm and could be travelled in both positions. 23:10: Restarting of normal operations, with the exception of the points 07BR that the 2 motor coaches on the runaway train were occupying. 8:34: After the departure of the 2 motor coaches the day after the incident, the Telm inspected the points 07BR, which were freed at 08:34. The normal situation was then re-established AFTER THE INCIDENT: THE ROLLING STOCK 22:03: A breakdown engineer arrived in Tienen. 22:18: The engineer informed the Traction distributor that the 2 motor coaches on the runaway train were in working order and could be moved. 0:10: After having made its remarks, SPC freed the two motor coaches. 7:21: A reserve driver pulled away with the 2 motor coaches of the runaway train in the direction of Leuven. 11:00: At Leuven station, the IB inspected the 2 motor coaches involved, with the help and support of the technical and inspection services of the SNCB/NMBS. Various simulations were made with the braking system and the lever in the driving cab. 8

9 3.4. ANALYSIS OF TRAIN DATA During the runaway of the vehicle, the lever was in neutral position: the speed was not recorded. Therefore the analysis of recordings of the train could not reveal anything. The neutral position of the lever also made the 2 safety systems ineffective: the "dead man's handle"; the TBL1+ system: placing a signal at danger on the route of the runaway train would not have had an impact ANALYSIS OF DRIVER REGULATIONS The HLT, SNCB/NMBS regulations for its drivers, specifies the measures to be taken by the driver when he must leave the driving cab for a maximum of 30 minutes: The driver keeps the train stationary: by placing the brake lever in a stable position for an emergency brake, or, with the FIL 1 function on traction engines equipped with an operational device for monitoring the braking system. The depression in the ABP should also be checked using the ABP pressure gauges." Illustration of the lever in an "emergency brake" position" 9 1 FIL : frein d'immobilisation en ligne

10 3.6. ANALYSIS OF ROLLING STOCK During his inspection, the driver found the release valve to the air brake reservoir in an open position. Illustration of the release valve (bron : NMBS) This release valve allows the pneumatic system to be cleansed, particularly removal of moisture from the air to optimise operation of the brake circuit. Originally the system was equipped with an air vent plug. This plug was replaced by a valve or lever, probably with the intention of simplifying cleansing of the pipe during maintenance in the workshop. This modification is not recent but no similar incidents have been reported to the IB. According to the information collected it seems impossible to depart with a fully opened tap: the brakes would not work and this would have been established during testing of the brakes. After the incident, no damage to the tap was reported during inspection of the rolling stock. It can not be established what caused the opening of the tap during the route. According to our hypothesis the valve was not fully closed upon departure resulting in a slight loss of pressure. Vibrations on the track caused the valve to open further until the pressure in the pipe was no longer sufficient. This modification alters a safety element of the rolling stock, namely the brake circuit. It is our opinion that this modification has not enough been reflected upon. That is why the risk for untimely opening of the lever, accidental interruption of the air brake pipe and stopping of the train was not detected. 10

11 4. CONCLUSION While the train E15440 was approaching Landen station, a pneumatic release valve on the brake circuit accidentally opened: the pressure in the automatic brake pipe (ABP) dropped, leading to application of the brakes. The train stopped 400 metres before Landen station. To unblock the brakes, the pressure had to be increased to the nominal value of 5 bars. The driver did not know about this accidental opening and, after telephone contact with the breakdown service in Leuven for advice, he carried out various operations and checks in his driving cab. He did not manage to increase the ABP pressure. He decided to carry out an external inspection of his train and notified the TC. During his inspection, he found the open release valve and closed it. In order to check the pressure in the ABP, he climbed into one of the driving cabs in the second motor coach and checked the pressure gauge: the release valve closed, the pressure in the brake pipe increased in accordance with requirements. To go back to the driving cab in the first motor coach, the driver got down from the second motor coach and went round the outside. The pressure in the brake pipe had then reached sufficient pressure for the brakes to release: due to gravity on the sloping track, the train started moving while the driver was still outside DIRECT CAUSES The direct cause of the runaway train was the releasing of the brakes following sufficient pressure in the ABP after the driver had closed the pneumatic valve. The elements contributing were: the lever was not in brake or emergency brake position; the parking brake wasn t engaged during the inspection of the train by the driver; the grade of the track which allowed the train to start moving by gravity; the AM80 did not have a system preventing runaway which could have stopped the train INDIRECT CAUSES Non-compliance with the HLT procedure by the driver for stopping his train while he was inspecting it; the untimely movement of the lever of the pneumatic release valve allowed air to escape from the main reservoir of one of the cars, resulting in a pressure drop in the ABP. 11

12 5. MEASURES TAKEN At an SNCB/NMBS level, the incident will be discussed in the Regular Training sessions, so as to draw drivers attention to this. On the other hand, a special document (TS A16M06) is being prepared and requires the workshops to remove the control lever on the various release taps. There are systems on certain types of rolling stock that allow runaways to be avoided: on Desiro train sets and M6 cars with a driving cab, systems preventing runaway and stopping control are managed by the ETCS system. on locomotives of type 18-19, such equipment is also installed but is managed independently from the ETCS. The requirements of the ETCS foresee that, on rolling stock where a driving cab is in service, braking should take place: if a traction unit reverses even if it is in forward gear, or if a traction unit moves while no gear has been applied. This allows a runaway to be avoided in the circumstances of the accident in Landen. According to the SNCB/NMBS timetable, in 2023, all SNCB/NMBS rolling stock will be equipped with ETCS and, as a result, with systems preventing runaway and stopping control. 6. RECOMMENDATION The lever of the pressure valve, which was initially not foreseen, was fitted in the workshop. Although supposedly this was done with the best intentions, this modification has increased the risk for an accidental opening of the tap of the pressure valve. The SNCB/NMBS should evaluate its procedures to ensure that prior to making modifications, the risks created by these modifications, which initially seem insignificant but possibly have an influence on the safety systems (braking system ), are analysed. 12

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14 Investigation Body for Railway Accidents and Incidents