Date:	Tuesday 17 April 2018
Time:	14:17 LT
Type:	Bell UH-1H Iroquois
Owner/operator:	O'Driscoll Aviation
Registration:	VH-HUE
MSN:	4807
Fatalities:	Fatalities: 0 / Occupants: 1
Other fatalities:	0
Aircraft damage:	Destroyed
Category:	Accident
Location:	24 km SE of Talbingo, NSW -   Australia
Phase:	Manoeuvring (airshow, firefighting, ag.ops.)
Nature:	External load operation
Departure airport:	Lobs Hole, NSW
Destination airport:	Lobs Hole, NSW
Investigating agency:	ATSB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
The pilot of a Garlick Helicopters UH-1H, registered VH-HUE, was to be conducting long-line lifting operations near Talbingo in the Snowy Mountains region of New South Wales, Australia. In the morning, the helicopter was prepared for flight at Tumut Airport, about 60 km north of the planned area of operation.
The helicopter departed Tumut Airport at about 08:04 for a positioning flight to a clearing 57 km south of Tumut, known as Lobs Hole, arriving at about 08:37.
This location was used as the base of operations for the lifting work on the day, referred to as the 'laydown area'. The operation was part of a proposed expansion of the Snowy Mountains Hydro-electric Scheme, known as the Snowy 2.0 project. The planned work on the day involved using helicopters to relocate components of a de-constructed drill-rig used for geotechnical survey within the 'area of operation'.
The lifting operation involved HUE and two AS350 helicopters. HUE was to be utilised for heavier loads, and the Squirrels to be utilised for the lighter loads.

Lifting operations involving HUE commenced at 13:08. Each run involved lifting drill-rig components from the drill site to the laydown area, before returning for the next lift. Each lift run, and return, was completed in about 5 minutes, with ground personnel preparing the next load between lifts. HUE had completed 11 lift runs, which the pilot reported were 'uneventful'. At about 14:14, the pilot positioned HUE for the twelfth run, in order to lift the drill rig motor.
As the helicopter approached for the twelfth lift, one of the loadmasters advised the pilot that more time was required to prepare the rigging and requested the pilot hold off for a short time. HUE
entered a holding circuit about 700 m to the north-east prior to making a very slow approach toward the drill site. The pilot recalled that the weather conditions were ideal, with a slight breeze and good visibility.
While waiting for a radio clearance to lift the drill rig motor, the pilot recalled conducting a full system check, and that all instruments indicated the helicopter was operating in the normal range. At about 14:15, the loadmaster requested the pilot approach the site in preparation for lifting the drill rig motor. As HUE approached overhead, the loadmaster informed the pilot that the rigging required re-checking. In order to minimise the rotor downwash on the people below, the pilot raised the collective to climb the helicopter, and the 100-foot long-line, above the tree canopy.
At about 14:17, as the helicopter started to climb, the pilot heard a loud mechanical 'screaming' noise and started planning for a forced landing. Witnesses also reported seeing 'smoke' and some advised they heard a 'bang' at about the same time. Almost immediately, the pilot also heard an audible alarm, followed by a noticeable yaw and engine power loss.
Just prior to the engine failure, HUE was about 200 to 250 ft above ground level, with a forward airspeed of about 20 to 25 kt.
The pilot broadcast a 'Mayday' call and attempted to conduct the forced landing (autorotation) into the Yarrangobilly riverbed, south-west of the lifting area and the ground personnel. The workers observed the helicopter being turned to the south-west, away from the drill site.
They described the helicopter as appearing to 'float' over the trees, before descending quickly. Around this time, the pilot commanded jettison of the long-line and lifting strops. The helicopter subsequently collided with trees and the riverbed. Ground personnel from the drill site immediately responded to the accident with fire extinguishers. They extinguished a small fire in the engine bay, removed the pilot from the wreckage, and performed first aid until emergency services arrived at 15:20. The pilot sustained serious injuries and the helicopter was destroyed.

Contributing factors
- On approach for a long-line lifting operation, the inner struts of the engine exhaust diffuser fractured as a result of fatigue cracking, which led to a complete loss of engine power.
- The fatigue cracks in the exhaust diffuser were likely present, but not detected in at least 34 daily and 2 phased maintenance inspections.
- Encore Aviation's maintenance practices and processes related to inspections, record keeping and trend monitoring, were likely inadequate to detect the potential impending failure of safety critical components. (Safety issue)
- The pilot did not have assurance that ground support personnel could vacate the drill site in an emergency. As a result, although the engine failed close to the cleared area, the pilot conducted the forced landing to a less suitable location, increasing the severity of impact forces during the subsequent collision with terrain.
- GHD's documented risk assessment for helicopter operations did not consider the hazard of an emergency landing at the drill site. This increased the risk that ground personnel were not clear of the load pick-up area in the event an emergency landing was required. (Safety issue)
- The upper torso restraint fitted to the pilot's seat was not worn during the long-line operations, which virtually certainly resulted in the pilot sustaining serious head injuries from the collision with terrain.
- Upper torso restraints were likely not routinely worn by a notable proportion of pilots conducting vertical reference flying operations in Australia, as they were likely not fit-for-purpose, increasing the risk of serious injury in the event of an accident.

https://www.brisbanetimes.com.au/national/nsw/man-injured-after-helicopter-crash-in-kosciuszko-national-park-20180417-p4za57.html
https://www.sbs.com.au/news/pilot-survives-fiery-kosciuszko-helicopter-crash
__________________________
https://www.casa.gov.au/aircraft-register?search_api_views_fulltext=O%27DRISCOLL+AVIATION&vh=&field_ar_serial=
http://www.odriscollaviation.com.au/index.php
__________________________
ATSB: https://www.atsb.gov.au/publications/investigation_reports/2018/aair/ao-2018-031/

Photo: ATSB

Date/time	Contributor	Updates
17-Apr-2018 06:37	gerard57	Added
17-Apr-2018 07:21	gerard57	Updated [Time, Aircraft type, Operator, Total occupants, Nature, Source, ]
17-Apr-2018 08:10	Iceman 29	Updated [Time, Aircraft type, Embed code, Narrative, ]
17-Apr-2018 08:11	Iceman 29	Updated [Embed code, Narrative, ]
17-Apr-2018 08:21	Iceman 29	Updated [Registration, Cn, Source, Narrative, ]
17-Apr-2018 08:27	Iceman 29	Updated [Source, Narrative, ]
18-Apr-2018 02:12	Iceman 29	Updated [Registration, Cn, Embed code, Narrative, ]
18-Apr-2018 10:38	harro	Updated [Destination airport, Embed code, ]
18-Apr-2018 12:24	Iceman 29	Updated [Source, ]
18-Apr-2018 16:40	A.J. Scholten	Updated [Cn, Narrative, ]
06-Jun-2018 07:13	Iceman 29	Updated [Source, Embed code, Narrative, ]
22-Sep-2020 09:47	Aerossurance	Updated [Location, Source, Embed code, Narrative, ]
22-Sep-2020 09:50	Aerossurance	Updated [Phase, ]
25-Dec-2021 20:16	harro	Updated [Photo, ]
12-Nov-2023 18:28	harro	Updated [Other fatalities, ]