Aviation safety investigations & reports

Collision with terrain involving Airbus Helicopters EC135 T1, VH-GKK, 10 km NNW Cooranbong, NSW, on 7 November 2015

Investigation number:
Status: Completed
Investigation completed
Phase: Final report: Dissemination Read more information on this investigation phase

Final Report

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What happened

At about 1730 AEDT[1] on 7 November 2015, the owner-pilot of an Airbus Helicopters (Eurocopter) EC135 T1, registered VH-GKK, departed Breeza, New South Wales, on a private flight to Terrey Hills, New South Wales. The flight was conducted under the visual flight rules and there were two passengers on board.

About 40 km to the south-west of the Liddell mine, the pilot diverted towards the coast, probably after encountering adverse weather conditions. Witnesses in the Laguna area observed the helicopter overfly the Watagan Creek valley in the direction of higher terrain. The helicopter was then observed to return and land in a cleared area in the valley.

After 40 minutes on the ground, the pilot departed to the east towards rising terrain in marginal weather conditions. About seven minutes later and approximately 9 km east of the interim landing site, the helicopter collided with terrain. A search was initiated about 36 hours later. The helicopter wreckage was found at about 1840 on 9 November 2015. The pilot and two passengers were fatally injured.

What the ATSB found

The ATSB found that the pilot departed an interim landing site under the visual flight rules in marginal weather conditions. The pilot likely encountered reduced visibility conditions leading to loss of visual reference leading to the collision with terrain.

The ATSB also found that the fixed, airframe-mounted emergency locator transmitter had been removed and that personal locator beacons which required manual activation were carried instead. While in this accident it did not affect the outcome for the occupants, the lack of activation, combined with the absence of flight notification information, delayed the search and rescue response.

Safety message

Weather-related general aviation accidents remain one of the most significant causes of concern in aviation safety and the following safety messages are key:

  • Avoiding deteriorating weather or instrument meteorological conditions (IMC)[2] requires thorough pre-flight planning, having alternate plans in case of an unexpected deterioration in the weather, and making timely decisions to turn back or divert.
  • Pressing on into IMC conditions without a current instrument rating carries a significant risk of encountering reduced visual cues leading to disorientation. This can easily affect any pilot, no matter what their level of experience. In the event of inadvertent entry into IMC, pilots are encouraged to contact air traffic control for assistance.
  • ELTs and PLBs are key safety devices that may become inhibited in a crash. In light of their respective limitations, it is worth considering the use of both.

EC135 T1, registered VH-GKK

EC135 T1, registered VH-GKK   Source: Supplied. Copyright: Not to be reproducedSource: Supplied. Copyright: Not to be reproduced


  1. Australian Eastern Daylight-saving Time is used in the report and is 11 hours ahead of Coordinated Universal Time (UTC).
  2. ‘Instrument meteorological conditions’ (IMC) describes weather conditions that require pilots to fly primarily by reference to instruments, and therefore under Instrument Flight Rules (IFR), rather than by outside visual references. Typically, this means flying in cloud or limited visibility.
Download final report
[Download  PDF: 2.15MB]

The occurrence


Safety analysis


Sources and submissions

General details
Date: 07 November 2015   Investigation status: Completed  
Time: 1930 EDT   Investigation level: Defined - click for an explanation of investigation levels  
Location   (show map): 10 km NNW Cooranbong   Investigation phase: Final report: Dissemination  
State: New South Wales   Occurrence type: Collision with terrain  
Release date: 24 April 2018   Occurrence category: Accident  
Report status: Final   Highest injury level: Fatal  

Aircraft details

Aircraft details
Aircraft manufacturer Airbus Helicopters  
Aircraft model EC135 T1 (Eurocopter)  
Aircraft registration VH-GKK  
Serial number 0103  
Operator Private  
Type of operation Private  
Sector Helicopter  
Damage to aircraft Destroyed  
Departure point Breeza, New South Wales  
Destination Sydney, New South Wales  
Last update 14 November 2018