Executive summary
On Friday 18 0ctober 2002, at about 0515, 2 wagons on the rear of southbound express freight Train 215 derailed while negotiating a turnout as the train departed from the Hamilton container transfer depot. The derailed wagons were detached and the train continued its journey south, but at about 0750, as it entered Te Kuiti, 3 further wagons derailed as they crossed the north-end turnout.
On Tuesday 25 March 2003, at about 0145, 12 wagons on northbound express freight Train 934 derailed while crossing the south-end turnout at Sawyers Bay.
Although undetected dragging brake rigging was identified as the main cause in each of these derailments, other safety issues included:
· the adequacy of wagon management and monitoring procedures to ensure safety critical Field Modification Instructions were actioned expeditiously
· lack of procedures to ensure out-of-code wagons were removed from service pending completion of required checks
· the dispatch of Train 215 from Hamilton following the first derailment before the cause of the derailment was identified
· the terminal brake test and train examination at Dunedin not detecting the dragging brake rigging on UK16281 before Train 934 departed.
One safety recommendation was made to Tranz Rail.
Report includes inquiry 02-122