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.
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
- Keep Your Eyes on the Hook! Underslung External Load Safety
- EC120 Underslung Load Accident 26 September 2013 – Report
- Unexpected Load: AS350B3 USL / External Cargo Accident in Norway
- Unexpected Load: B407 USL / External Cargo Accident in PNG
- Load Lost Due to Misrigged Under Slung Load Control Cable
- Fallacy of ‘Training Out’ Error: Japanese AS332L1 Dropped Load
- UPDATE 28 June 2020: Maintenance Issues in Fire-Fighting S-61A Accident
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.