Helicopter External Sling Load Operation Occurrences in New Zealand

HESLO (Under Slung Load) Occurrences in New Zealand

Data issued by  the NZ Helicopter Association and NZ CAA show a rising trend in reported occurrences in NZ relating to external load operations and equipment.

HESLO NZ

Around 60% of the reports relate to HESLO equipment or its rigging and about 35% relate to operations with a load.

The report mentions UK CAA CAP426 Helicopter External Load Operations from 2006 as a safety resource.  CASA issued Airworthiness Bulletin 25-006 “to notify operators and maintainers of additional safety information and current design standards for cargo hooks installed in helicopters”.  It discusses phenomena such as Dynamic Rollout (or Ring Reversal), Jammed Loads / Hooks, Uncommanded Release / Inadvertent Cargo Hook Opening etc.

Other Safety Resources

Also: the UK AAIB report on a fatal accident to AS350B2 G-PLMH during HESLO with a boat at Loch Scadavay, Western Isles, Scotland, 13 June 2018, was issued in July 2019.


Aerossurance has extensive air safety, operations, HESLO, airworthiness, human factors, aviation regulation and safety analysis experience.  For practical aviation advice you can trust, contact us at: enquiries@aerossurance.com