atsb final report released 16 may 2013 - Ambulance Service of NSW

was night vision goggle (NVG)-capable; however, the crew that was on duty tooperate that helicopter that night was not qualified to conduct winching operationsusing NVGs. At the time of the accident, the operator’s AW139 helicopters werenot permitted to conduct NVG winching operations.Winching procedureHi-line transferThe operator’s operations manual included procedures in support of vertical lift andHi-line transfer winching techniques. The Hi-line transfer procedures stated that:A Hi-line procedure is used when conducting either over water or over landrescue winch recoveries when normal winching would be hazardous.a. When the winching area is confined or obstructed in such a way thatthere is a risk of the winch cable snagging or the RCM [rescuecrewman] / MA [medical attendant] striking obstructions...c. When normal winching techniques would be unable to effecttransfer.The Hi-line transfer technique involved the attachment of one end of a rope(Hi-line) to the rescue winch hook and the delivery of the other end to the winchingarea using the rescue winch. The technique generally employed a Hi-line attendantat the winching area who used the rope to manoeuvre the winch hook and occupantsas the rescue winch was raised or lowered. The operations manual cautioned thatexcessive cable angle was to be avoided during Hi-line transfers in order to reducethe tendency for a swing to develop. The manual recognised that in certaincircumstances, the rescue crewman may be the last to be recovered and that, in thatsituation, there would be no Hi-line attendant on the ground during the recovery.This increases the risk that a swing may develop during the last transfer.The crew’s plan to recover the injured canyoner relied on a technique that wassimilar to the Hi-line transfer, especially with regard to the role of the pilot andACM. However, the operator advised that the use of a self-stabilising rope systemanchored to a secure point was not a procedure that was either documented or forwhich its crews had trained. The ASNSW advised that the use of a self-stabilisingrope system, where the helicopter was laterally offset from the pick-up point, hadnever been undertaken by its staff.The operator advised that the past conduct of high profile winch rescues, where thehelicopter was offset laterally was ‘strong in folklore’ among the ambulance andflight crews, but that the use of such techniques had been actively discouraged. Incontrast, a number of paramedics who had been trained as ambulance rescuecrewmen (ARC) by the operator reported that winching from an offset position hadnot, in their mind, been actively discouraged. As there was no documented evidenceprovided to confirm either understanding, the difference of opinion could not bereconciled.- 28 -