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Rail Accident Report Freight train derailment at Heworth, Tyne and Wear 23 October 2014 Report 16/2015 September 2015 This investigation was carried out in accordance with: l the Railway Safety Directive 2004/49/EC; l the Railways and Transport Safety Act 2003; and l the Railways (Accident Investigation and Reporting) Regulations 2005. © Crown copyright 2015 You may re-use this document/publication (not including departmental or agency logos) free of charge in any format or medium. You must re-use it accurately and not in a misleading context. The material must be acknowledged as Crown copyright and you must give the title of the source publication. Where we have identified any third party copyright material you will need to obtain permission from the copyright holders concerned. This document/publication is also available at www.raib.gov.uk. Any enquiries about this publication should be sent to: RAIB Email: [email protected] The Wharf Telephone: 01332 253300 Stores Road Fax: 01332 253301 Derby UK Website: www.gov.uk/raib DE21 4BA This report is published by the Rail Accident Investigation Branch, Department for Transport. Preface The purpose of a Rail Accident Investigation Branch (RAIB) investigation is to improve railway safety by preventing future railway accidents or by mitigating their consequences. It is not the purpose of such an investigation to establish blame or liability. Accordingly, it is inappropriate that RAIB reports should be used to assign fault or blame, or determine liability, since neither the investigation nor the reporting process has been undertaken for that purpose. The RAIB’s findings are based on its own evaluation of the evidence that was available at the time of the investigation and are intended to explain what happened, and why, in a fair and unbiased manner. Where the RAIB has described a factor as being linked to cause and the term is unqualified, this means that the RAIB has satisfied itself that the evidence supports both the presence of the factor and its direct relevance to the causation of the accident. However, where the RAIB is less confident about the existence of a factor, or its role in the causation of the accident, the RAIB will qualify its findings by use of the words ‘probable’ or ‘possible’, as appropriate. Where there is more than one potential explanation the RAIB may describe one factor as being ‘more’ or ‘less’ likely than the other. In some cases factors are described as ‘underlying’. Such factors are also relevant to the causation of the accident but are associated with the underlying management arrangements or organisational issues (such as working culture). Where necessary, the words ‘probable’ or ‘possible’ can also be used to qualify ‘underlying factor’. Use of the word ‘probable’ means that, although it is considered highly likely that the factor applied, some small element of uncertainty remains. Use of the word ‘possible’ means that, although there is some evidence that supports this factor, there remains a more significant degree of uncertainty. An ‘observation’ is a safety issue discovered as part of the investigation that is not considered to be causal or underlying to the event being investigated, but does deserve scrutiny because of a perceived potential for safety learning. The above terms are intended to assist readers’ interpretation of the report, and to provide suitable explanations where uncertainty remains. The report should therefore be interpreted as the view of the RAIB, expressed with the sole purpose of improving railway safety. The RAIB’s investigation (including its scope, methods, conclusions and recommendations) is independent of any inquest or fatal accident inquiry, and all other investigations, including those carried out by the safety authority, police or railway industry. Report 16/2015 September 2015 Heworth This page is intentionally left blank Report 16/2015 4 September 2015 Heworth Freight train derailment at Heworth, Tyne and Wear, 23 October 2014 Contents Preface 3 Summary 7 Introduction 8 Key definitions 8 The accident 9 Summary of the accident 9 Context 10 The sequence of events 13 Key facts and analysis 16 Background information (Wagon) 16 Background information (Track) 18 Identification of the immediate cause 21 Identification of causal factors 21 Identification of underlying factors 47 Observations 57 Previous occurrences of a similar character 58 Previous RAIB recommendations relevant to this investigation 60 Recommendation that was being implemented at the time of the accident 60 Recommendations that are currently being implemented 62 Actions reported as already taken or in progress relevant to this report 66 Summary of conclusions 68 Immediate cause 68 Causal factors 68 Underlying factors 69 Additional observations 69 Learning points 70 Recommendations 71 Report 16/2015 5 September 2015 Heworth Appendices 74 Appendix A - Glossary of abbreviations and acronyms 74 Appendix B - Glossary of terms 75 Appendix C - Sources of Evidence 79 Appendix D - Dynamic modelling of the wagon’s ride performance 80 Appendix E - Cyclic top measurement, actions and repair 83 Report 16/2015 6 September 2015 Heworth Summary Summary At about 15:25 hrs on 23 October 2014, a freight train derailed just after passing through Heworth station on the railway line from Sunderland to Newcastle. It was travelling at 51 mph (82 km/h) when the leading wheelset of the tenth wagon derailed on track with regularly spaced dips in both rails, a phenomenon known as cyclic top. The train continued for about 1.4 miles (2.3 km) towards Newcastle where it was stopped by the signaller, who had become aware of a possible problem with the train through damage to the signalling system. By the time the train stopped, both of the wagon’s wheelsets were derailed and its suspension was damaged. There was also damage to the track, points, signalling cables and signalling equipment that the derailed wheelsets had run over. There were no injuries. The immediate cause of the derailment was a combination of a loss of damping within the suspension on one corner of the wagon and dips in the track. The wagon was found to have a worn suspension component on its leading right-hand corner which made the leading left-hand wheel susceptible to unloading and lifting up when responding to dips in the track. The wagon’s maintenance regime had not identified this worn component. The excessive wear was probably due to a problem with the alignment of the wheelset within its suspension. The severity of the dips in the track required Network Rail to impose an emergency speed restriction but no such restriction had been put in place. The dips formed continually due to water in the track not draining away and although the track inspection regime had identified this defect many times, often no repair took place. Occasionally the local Network Rail track maintenance team carried out manual repairs but these were ineffective. An underlying cause was that the local track maintenance team was unable to cope with the volume of work it had to do. This was due to a combination of reduced numbers of track maintenance staff over a long period of time, changes to the arrangements for working safely while on the track, restrictions on gaining access to the track at Heworth and changes to how the track was inspected. A further underlying cause was that Network Rail’s audit and self-assurance processes did not alert senior management to the extent of non-compliances to maintenance processes or trigger earlier action to resolve persistent problems affecting the track assets in the local track maintenance team’s area. The RAIB has made five recommendations. One recommendation is directed to Freightliner and covers mitigating the risk of this type of wagon’s ride performance being degraded by worn suspension components. The other four are directed to Network Rail and cover: l investigating why water is not draining from the track where the train derailed; l reviewing whether defects found by the track inspection regime are accurately recorded and that corresponding repair work is planned; l understanding and taking action to address why the track assets in this area consistently have high numbers of defects; and l understanding and taking action to address why its management arrangements allowed the non-compliances to processes for track maintenance found by this investigation to go undetected. Report 16/2015 7 September 2015 Heworth Introduction Introduction Key definitions 1 Metric units are used in this report, except when it is normal railway practice to give speeds and locations in imperial units. Where appropriate the equivalent metric value is also given. 2 The report contains abbreviations and technical terms (shown in italics the first time they appear in the report). These are explained in appendices A and B. Sources of evidence used in the investigation are listed in appendix C. Report 16/2015 8 September 2015 Heworth The accident Summary of the accident The accident 3 At about 15:25 hrs on 23 October 2014, a freight train derailed just after passing through Heworth station on the railway line from Sunderland to Newcastle (figure 1). It was travelling at 51 mph (82 km/h) when the leading wheelset of the tenth wagon derailed on track with regularly spaced dips in both rails, a phenomenon known as cyclic top. Heworth Location of accident © Crown Copyright. All rights reserved. Department for Transport 100039241. RAIB 2015 Figure 1: Extract from Ordnance Survey map showing location of accident 4 The train continued as its driver was unaware of the derailment, although the driver applied the brakes to slow the train down as it approached Newcastle. By the time it reached St James Bridge junction (figure 2) the trailing wheelset on the tenth wagon had been pulled into derailment.