02.09.2020 1 The Alexander L. Kielland accident The Inquiry Commission’s Investigation of the causes of the capsizing and the assessment of evacuation and rescue operations and the associated recommendations & Some comments, especially on what were NOT causes of the capsizing Torgeir Moan NTNU 1 2 Content Mandate and members of the Inquiry Commission Background: - Principles of accident investigations - ALK (P89) lifecycle history vs status of technology & regulations Possible causes of the accident - The Commission’s approach: what causes platform accidents in general (i.e. the risk picture) - «all possible causes» need to be investigated «Media rumors» Facts - the «collapsed structure», environmental conditions at the time of the accident - the life cycle info.: design and analyses (digital twin), fabrication- and operation reports, .. - inspection of sister rig - Henrik Ibsen (P88) & other semi-submersibles - Industry practice : rules & regulations – and their implementation in practice - Examinations after the uprighting of ALK (in 1983) - Personal comments about Expert and Witness statements & Media Brief description of the causes of the capsizing and associated recommendations - technical and physical a well as human and organizational factors for A. structural failure(loss of column D) and B. flooding and capsizing - comments on circumstances that were not «cause of the accident» Brief assessment of evacuation and rescue operations – and assoc. recommendations Final remarks Torgeir Moan, NTNU 2 1 02.09.2020 3 Mandate for the Inquiry • Investigate the conditions of the accident and, if possible, bring to light the causes of the accident (and recommendations to improve the safety - as agreed with the Ministry of Justice after the appointment) • Assess the performance of the rescue equipment and how the evacuation and rescue operation were executed and come up with recommendations Inquiry Commission’s members • Thor Næsheim, Magistrate, Sandnes • Torgeir Moan, Professor, marine technology, NTH (NTNU) • Sivert Øveraas, Director, Shipowners association • Per Bekkvik, Platform manager/ship captain • Aksel Kloster, Personal manager, National Guard and Oil secr. LO - later replaced by Jan B Strømme, «Oljekartellet» Engagement of Kjell Straume, MSc as a technical secretary and several, independent experts (e.g. from NTH,SINTEF, U.Aachen, Statoil) for special investigations Torgeir Moan, NTNU 3 Background:4 Principles for accident investigations Technical/physical event sequence Deficient rules and regulations (and industry practice at large) when it is realized that the industry practice «at large» is not good enough Human errors and omissions Individual by those «errors» must be - doing the job (and their seen in view of Fabrication superiors in the organisation) the management- during the different life cycle and safety culture in the relevant phases organisations and or regulatory bodies - doing the control of integrity management during the lifecycle The facility’s lifecycle phases facility’s The based on a «risk management tool»: Mangement Oversight Risk Tree (MORT), (Johnson, 1973) Torgeir Moan, NTNU 4 2 02.09.2020 5 Background: Principles for accident investigations, cont.d Holistic assessment of all possible causes/factors of influence – in an objective manner, i.e.: Objectivity Factuality Impartiality Neutral Truth Relevance Balance presentation J. Westerståhl in the book by Hadenius & Weibull (ed.) Massemedier, Aldusserien, Stockholm, 1978. Torgeir Moan, NTNU 5 6 Background: The development of the offhore O&G industry and the regulatory regime Brief ALK history o ALK was Pentagon-rig no. 9 (denoted P89) o Developed in the late 1960s, the first one, P81, was built in 1969 - The P82-P91 rigs were further developed and built based on «similar analysis and drawings» and delivered in 1973-1977 (CFEM, Rauma Repola, Marathon) . o - ALK (P89) was approved in 1973-74 and delivered from CFEM in 1976. Pioneering period for the Norwegian O&G activity :1970-1980 • Maritime Dir. regulations for drilling rigs1973, 1975 • DNV: rules for mobile rigs 1973 (ABS 1968) • Petr. Dir. was established in 1973 – Ptil separated as a unit in 2004 • The Petroleum Law 1985 – Petr. Dir. as a coordinating body authority Milestones: ALK accident in 1980 Research Program «Safety Offshore» 1978-82 - With several implications on safety efforts by the induystry and authorities Torgeir Moan, NTNU 6 3 02.09.2020 7 Background info. for the Inquiry - assessment of regulations and standards & their use in practice Article published in - experiences from other accidents «Teknisk Ukeblad» (Inquiry reports, risk analyses), e.g. Vol.127. No. 11. T.Moan: “Risk Assessment of Mobile Rig 28.02.1980 Operations”, Report SK/R46, NTH, 1979, (a month before the ALK accident) Safety Offshore (“Sikkerhet på Sokkelen”) research program. Overview of world wide accidents for mobile (1970-1980) platforms, made in connection with the finalizing of the ALK Inquiry Report: NOU 1981:11 organized according to the technical-physical sequence of events Torgeir Moan, NTNU 7 Possible8 causes of the ALK accident Possible causes (circulating in media and also presented to the Commission in various ways): - open ventilators, watertight doors, (published in 1981) - occurence of cracks (the Commission informed the parties about the D6 fatigue failureene 31.03.80) - ship impact Hovden, Jan; Vinje, Kjell E. A.: Disaster journalism, - «deficient platform structure, struct. materials the newspaper coverage of - «overtensioning of mooring lines» – the "Alexander L. Kielland" especially the first days platform accident, - explosion (sabotage) theory Yrkeslitteratur, Oslo, ca. 1983. The argumentation for and against the theories – were influenced by self interests (The Commission investigated the various potential causes, but only briefly mention factors that were insignificant to the causes of the accident, in the Commission’s report). Torgeir Moan, NTNU 8 4 02.09.2020 9 Facts in the Inquiry - The «collapsed» struct. failure surfaces, material properties, (SINTEF, Statoil) - Inspection of sister rig- Henrik Ibsen (D-column, diver-inspections , - inspection av the ALK platform especially with respect to cracks at i 1980(!) and after uprighting in 1983 other locations – e.g. on brace B5, Material tests , etc) - wave-, wind conditions at the timeof the accident and during operation - design basis (drawings, criteria, analyses,operational manual), - fabrication- (inspection-) - and operational logs - annex: design calc. (stability and strength of hull and mooring system) fatigue analyses (which were not carried out for design) (SINTEF/NTH, U.Aachen) stability- and flooding analyses (NTH) - review of relevant regulatory requirements and their use - interrogation/hearing of designers, fabricators and inspectors during fabrication, class societies, Maritime Dir., Petr.Dir., owners, surviving maritime crew and hotel guests (normally together with the Stavanger Police) Torgeir Moan, NTNU 9 10Personal comments about Expert & Witness statements & Media Hearing of involved parties: - The French designers and fabricators, class society (DNV, Lloyds Register (LR) , Mar.Dir., Operator (Stavanger Drilling) specialists on strength and stability analysis - Maritime crew - Others (hotel guests) Opinions expressed by other org. and media Necessary Many persons – also engineers – have perspective: made statements about the accident Relevant without a holistic perspective of the facility engineering and its life cycle history. competence, familiarity with For instance, media have speculated on accident Fabrication the accident causes based some physical observations during operation by personnel taxonomy The accident took place during on board – without insight about the design operation and fabrication (e.g. the digital twin of the platform) – and often with a certain (hidden) Operation «agenda». Torgeir Moan, NTNU 10 5 02.09.2020 11 Document delivered to the Ministry of Justice, March 1981: NOU 1981:11 - Main report 216 pages - Technical annexes 143 pages - Documents from different experts Mandate •Investigate the conditions of the accident and, if possible, bring to light the causes of the accident (and reommendations to improve the safety (as agreed with the Ministry of Justice after the appointment) •Assess the performance of the rescue equipment and how the evacuation and rescue operation were executed and come up with «unauthorized In Norwegian recommendations translation» with a summary in English Torgeir Moan, NTNU 11 12 Uprighting of ALK The main motivation (of the government) for the uprighting was the search for the remains of 36 missing persons In 1980:Inspection of the D-column and the platform: - dry inspection of pieces cut at failure locations - under water inspections by divers on behalf of the Commission In 1983 (after uprighting): - Further investigation of structural damages relating to the accident causes Additional document (hampered by damages caused After uprighting during the uprighting of the platform) Delivered in 1983: - Status of doors, ventilators and NOU 1983:53 valves (associated with flooding, capsizing) Parliament message No. 41, 1983-84 Torgeir Moan, NTNU 12 6 02.09.2020 13 Accident Causes Accidents can be - Fatalities - Environmental investigated from: damage Technical-physical point of view Critical - Property - Capsizing or total loss of event damage structural integrity commonly develops in a Fault Event tree tree sequence of events Human and organizational