Inquiry into the Derailment of a Freight Train at Cahir Viaduct on 7th October 2003 (Cover image courtesy of Radio Teilifís Éireann) Inquiry into Derailment at Cahir Viaduct on 7th October 2003 – Report (version 1.2) 22/12/2005 Contents Contents .............................................................................................................................. 3 Tables.................................................................................................................................. 4 Illustrations ......................................................................................................................... 5 Illustrations ......................................................................................................................... 5 1 Executive Summary:................................................................................................... 6 2 Referencing Convention: ............................................................................................ 8 3 The accident:............................................................................................................. 10 4 Background............................................................................................................... 12 4.1 The Railway:..................................................................................................... 12 4.2 The Site:............................................................................................................ 13 4.3 The Service: ...................................................................................................... 14 4.4 The Weather:..................................................................................................... 15 4.5 The Track:......................................................................................................... 15 4.6 The Viaduct:...................................................................................................... 17 4.7 The Train:.......................................................................................................... 19 5 Events immediately prior to and post derailment: .................................................... 21 5.1 The Journey:...................................................................................................... 21 5.2 Response: .......................................................................................................... 21 5.3 Examination, Recovery and Testing:................................................................ 23 6 Inspection and Maintenance ..................................................................................... 24 6.1 The Track:......................................................................................................... 24 6.2 The Viaduct:...................................................................................................... 25 6.2.1 Inspection Standards:................................................................................ 25 6.2.2 Divisional Inspection Cards:..................................................................... 26 6.2.3 Inspections Pre-accident: .......................................................................... 26 6.2.4 Inspections Post-accident:......................................................................... 26 6.2.5 Structural Drawings: ................................................................................. 27 6.2.6 Maintenance.............................................................................................. 27 6.2.7 Maintenance Standards:............................................................................ 28 6.3 The Train:.......................................................................................................... 28 7 Analysis..................................................................................................................... 30 7.1 Derailment Sequence: ....................................................................................... 30 7.2 Cause of derailment: ......................................................................................... 33 7.2.1 Speed:........................................................................................................ 33 7.2.2 Malicious act;............................................................................................ 33 7.2.3 Catastrophic failure of the viaduct;........................................................... 34 7.2.4 Viaduct deflection:.................................................................................... 34 7.2.5 Viaduct resonance:.................................................................................... 35 7.2.6 Train stability in operation:....................................................................... 35 7.2.7 The Secondary Deck:................................................................................ 37 7.3 Assessment of the Secondary Deck of the Viaduct .......................................... 38 7.3.1 Type and Condition of timbers: ................................................................ 39 7.3.2 Dilution of standards:................................................................................ 40 7.3.3 Complexity................................................................................................ 41 3 Inquiry into Derailment at Cahir Viaduct on 7th October 2003 – Report (version 1.2) 22/12/2005 7.3.4 Inspection and Maintenance: .................................................................... 43 7.3.5 Replacement of way-beams:..................................................................... 44 7.3.6 Derailment containment:........................................................................... 45 7.3.7 Condition of way-beam 6: ........................................................................ 48 7.3.8 Possible derailment mechanism:............................................................... 51 7.4 Risk to life:........................................................................................................ 52 7.5 EM50: ............................................................................................................... 52 8 Conclusions:.............................................................................................................. 54 8.1 Safety Criticality:.............................................................................................. 55 8.2 Derailment protection: ...................................................................................... 56 8.3 Training Needs Analysis................................................................................... 57 8.4 Track Monitoring.............................................................................................. 57 8.5 EM50................................................................................................................. 58 8.6 Asset management: ........................................................................................... 59 8.7 Internal auditing:............................................................................................... 60 8.8 Speed Restriction and Monitoring: ................................................................... 60 8.9 Driver Communications:................................................................................... 62 Appendix 1: Wagon details............................................................................................... 63 Appendix 2: Cross-section drawings ................................................................................ 64 Appendix 3: Plan diagram of intact bridge deck .............................................................. 69 Tables Table 1 Table showing times of accident response events .............................................. 22 Table 2 Table showing results of simulated wagon test for track twist........................... 37 Table 3 Table of train consist, vehicle registration, weight and exam details................. 63 4 Inquiry into Derailment at Cahir Viaduct on 7th October 2003 – Report (version 1.2) 22/12/2005 Illustrations Figure 1 Plan diagram of viaduct showing conventions used in the text ......................... 8 Figure 2 Aerial shot of front of train (by courtesy of Radio Teilifís Éireann) ............... 10 Figure 3 Aerial shot of viaduct (by courtesy of Radio Teilifís Éireann)........................ 10 Figure 4 Map of national rail network (by courtesy of Iarnród Éireann)....................... 12 Figure 5 Map showing location of viaduct (by courtesy of Iarnród Éireann)................ 12 Figure 6 Viaduct from Limerick side ............................................................................ 14 Figure 7 Viaduct from Limerick bank, showing collapsed deck and wagons............... 16 Figure 8 Viaduct cross-section diagram......................................................................... 17 Figure 9 Way-beams over transverse girder 18............................................................. 19 Figure 10 Flitch plate and top flange reinforcement plate at transverse girder 20......... 19 Figure 11 20 tonne two-axle cement wagon................................................................... 20 Figure 12 View of collapsed deck from Limerick side of Viaduct ................................. 31 Figure 13 Detail of Down side after debris was removed..............................................