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Rail Accident Report Derailment at Grayrigg 23 February 2007 Report 20/2008 October 2008 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 2008 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.raib.gov.uk DE21 4BA This report is published by the Rail Accident Investigation Branch, Department for Transport. Derailment at Grayrigg, 23 February 2007 Contents Preface 5 General terms used in the report 5 Summary of the report into the derailment at Grayrigg on 23 February 2007 6 The Accident 15 The Investigation 25 The Infrastructure: Evidence and Analysis 29 Degradation of Lambrigg 2B points 30 Inspection and maintenance 56 Other accidents and incidents involving S&C stretcher bars 79 Network Rail’s management arrangements 82 Safety Regulation 109 The cause of the derailment 123 The Derailed Train: Evidence, Analysis and Conclusions 131 Rescue and First Aid: Evidence, Analysis and Conclusions 153 Action reported as already taken or in progress 163 Recommendations 169 Appendices 187 Appendix A - Glossary of abbreviations and acronyms 188 Appendix B - Glossary of terms 189 Appendix C - Key standards current at the time 205 Appendix D - An overview of points operation and terms 208 Appendix E - Bolted Joints 213 Appendix F - On-train recording of infrastructure features 215 Appendix G - Definition of cant and cant deficiency 220 Appendix H - Access restrictions at Lambrigg 221 Appendix I - Signalling maintenance standards 224 Appendix J - Compliance & Assurance 226 Appendix K - Overview of the relationship between Network Rail’s engineering and maintenance organisations 228 Appendix L - Actions taken by Network Rail in response to the Potters Bar investigations 231 Rail Accident Investigation Branch Report 20/2008 www.raib.gov.uk October 2008 Appendix M - The Role of the Safety Regulator 241 Appendix N - Actions taken in response to recommendations from the Potters Bar derailment that were directed at HMRI 243 Appendix O - Network Rail SIN 97, 99 and 101 results 247 Appendix P - Urgent Safety Advice issued by RAIB 250 Appendix Q - Summary of egress routes 254 Rail Accident Investigation Branch Report 20/2008 www.raib.gov.uk October 2008 Preface Preface 1 The purpose of a Rail Accident Investigation Branch (RAIB) investigation is to determine the cause of an accident or incident, with the aim of preventing future accidents and incidents, and of improving railway safety. 2 The RAIB does not consider or determine blame or liability, or carry out prosecutions. General terms used in the report 3 This report is about the derailment of an express passenger train which occurred on 23 February 2007 near Grayrigg in Cumbria, on the West Coast Main Line (WCML). The general orientation of the WCML is on a north-south axis. However, at the location where the derailment occurred, trains running from London to Glasgow are travelling in an easterly direction. For the purposes of consistency, the terms ‘north’ and ‘south’ are used in this report when referring to infrastructure or events on the Glasgow and London side of the derailment respectively. 4 The geographical location on the WCML in the area of Grayrigg is established by the distance from a ‘zero’ datum at Lancaster station, measured in miles and chains. 5 At various places in this report, reference is made to the ‘right’ or ‘left’ side of the train or track. In all cases, this refers to the perspective of a person facing north in the direction the train was travelling, from London to Glasgow. 6 The location of the derailment was at Lambrigg emergency crossover, in the vicinity of the village of Grayrigg. In this report the derailment is referred to as being at Grayrigg, the nearest location of note, but the crossover and points are referred to as Lambrigg. 7 Throughout the report the term Switches and Crossings (S&C) is used to describe all means of intersection of railway lines, including diamonds, slips, and other more complex layouts. The term ‘points’ is used when specific reference is made to points or the points at Lambrigg. 8 Appendix A to this report contains explanations of acronyms and abbreviations and Appendix B explains technical definitions that are shown in italics the first time that they appear in the report. Rail Accident Investigation Branch Report 20/2008 www.raib.gov.uk October 2008 Summary of the report Summary of the report into the derailment at Grayrigg on 23 February 2007 Key facts about the accident 9 On 23 February 2007 at 20:12 hrs, an express passenger train derailed at facing points, known as Lambrigg 2B points, located near Grayrigg in Cumbria (Figure 1). The train, reporting number 1S83, was the 17:15 hrs service from London Euston to Glasgow, operated by West Coast Trains Ltd, part of Virgin Rail Group (referred to as ‘Virgin Trains’ in the remainder of this report), and was travelling at 95 mph (153 km/h). All nine vehicles of the Class 390 Pendolino unit derailed (Figure 2). Eight of the vehicles subsequently fell down an embankment and five turned onto their sides. Location of accident © Crown Copyright. All rights reserved. Department for Transport 10002027 2008 Figure 1: Extract from Ordnance Survey map showing location of accident 2 7 8 9 a points 1 Figure 2: Aerial view of derailed train Rail Accident Investigation Branch Report 20/2008 www.raib.gov.uk October 2008 10 The train was carrying four crew and at least 105 passengers at the time of the accident. 11 One passenger was fatally injured; 28 passengers, the train driver and one other crew member received serious injuries and 58 passengers received minor injuries. The remaining 18 passengers and two crew members were not physically injured in the derailment. 12 The railway line through the area remained closed until 12 March 2007. Initially this was for the rescue of the injured, then solely for accident investigation, then (in parallel) for Summary of the report accident investigation, vehicle recovery and repairs to the infrastructure, and finally to complete the repairs to the infrastructure. Summary of the derailment and its causes 13 The train derailed as it passed over 2B points which were in an unsafe state. A combination of failures of stretcher bars and their joint to the switch rails allowed the left- hand switch rail to move, under its natural flexure, towards the left-handstock rail. The left-hand wheels of either the first or secondbogie on the leading vehicle (it is not clear which) passed the wrong side of the left-hand switch rail and were forced into the reducing width between the switch rails. The wheels then derailed by climbing over the rails. All the other vehicles of the train derailed as a consequence. Figures 3 and 4 show the key details of the points. 14 This situation arose at 2B points because of a combination of three factors. These were: • the failure of the bolted joint connecting the third permanent way stretcher bar to the right-hand switch rail; • incorrect set up of the points with excessive residual switch opening; and • the omission of the scheduled weekly inspection on 18 February 2008. All three were necessary for the accident to occur. 15 The bolts holding the third permanent way stretcher bar to the right-hand switch rail became loose, and subsequently completely undone. As a result of this, and the excessive residual switch opening, the left-hand switch rail was struck by the inner faces of passing train wheels, giving rise to large cyclic forces. As a consequence, rapid deterioration of the condition of the remaining stretcher bars and their fasteners occurred. This led to the left-hand switch rail becoming totally unrestrained. 16 This deterioration took place over a period of at least eleven days prior to the accident. An inspection, scheduled for 18 February, which should have detected the degradation, was omitted. 17 There were a number of shortcomings in Network Rail’s safety management arrangements which were underlying factors in this accident. Rail Accident Investigation Branch 7 Report 20/2008 www.raib.gov.uk October 2008 Summary of the report Third permanent way stretcher bar Minimum free wheel clearance position Swan neck insulated joint Bracket Supplementary Fastener drive Second permanent way stretcher bar Left-hand Right-hand stock stock rail rail Left-hand Right-hand switch switch rail rail Drive rod First permanent way stretcher bar Points machine Switch toes Lock stretcher bar Detector Switch rail rods extension pieces Figure 3: Layout of points showing switch and stock rails and stretcher bars Rail Accident Investigation Branch 8 Report 20/2008 www.raib.gov.uk October 2008 Swan neck insulation joint Summary of the report Track Gauge Wheelset back-to-back Flange back clearance Wheel flange thickness Residual switch opening Free