Aviation safety investigations & reports

Ditching involving a MBB BK117-A3 helicopter, ZK-IED, Porirua Harbour, Pauatahanui Arm, New Zealand, on 2 May 2017

Investigation number:
Status: Completed
Investigation completed


On 2 May 2017, the pilot of a Messerschmitt-Bölkow-Blohm BK117-A3 helicopter, registered ZK‑IED, was tasked to relocate power poles from the northern side of the inlet to the southern side at Porirua Harbour, Pauatahanui Arm, New Zealand. The pilot reported that while in the cruise at about 300 ft, the helicopter started an un-commanded yaw, at which point the pilot released the sling load and entered into an autorotation onto the water. The helicopter was substantially damaged, and the pilot was uninjured.

On 3 July 2017, the New Zealand Transport Accident Investigation Commission (TAIC) requested Australian Transport Safety Bureau (ATSB) technical assistance with data recovery from a global positioning system (GPS) device that was onboard the helicopter at the time of the ditching. In accordance with paragraph 5.23 of Annex 13 to the Convention on International Civil Aviation Aircraft Accident and Incident Investigation, the ATSB appointed an accredited representative (ATSB investigator) to the TAIC investigation. To facilitate this request, the ATSB initiated an external investigation under the provisions of the Transport Safety Investigation Act 2003.

The ATSB successfully recovered the data from the GPS and provided a copy to the TAIC on 4 September 2017.

TAIC is responsible for the release of the final investigation report into this accident. Any enquiries in respect of the ongoing TAIC investigation or release of the investigation report should, in the first instance, be directed to the:

Transport Accident Investigation Commission
Level 9, 114 The Terrace
PO Box 10323
Wellington, 6143, New Zealand


The information contained in this web update is released in accordance with section 25 of the
Transport Safety Investigation Act 2003 and is derived from the initial investigation of the occurrence. Readers are cautioned that new evidence will become available as the investigation progresses that will enhance the ATSB's understanding of the accident as outlined in this web update. As such, no analysis or findings are included in this update.

General details
Date: 02 May 2017   Investigation status: Completed  
  Investigation level: Short - click for an explanation of investigation levels  
Location   (show map): Porirua Harbour, Pauatahanui Arm, New Zealand    
State: International   Occurrence type: Ditching  
Release date: 30 November 2017   Occurrence category: Accident  
Report status: Final   Highest injury level: None  

Aircraft details

Aircraft details
Aircraft manufacturer Messerschmitt-Bolkow-Blohm  
Aircraft model BK117-A3  
Aircraft registration ZK-IED  
Type of operation Unknown  
Sector Helicopter  
Damage to aircraft Substantial  
Last update 14 November 2018