Aviation safety investigations & reports

Collision with terrain involving YAK-9UM, VH-YIX, near Latrobe Valley Aerodrome, Victoria, on 7 September 2018

Investigation number:
AO-2018-061
Status: Active
Investigation in progress
Phase: Final report: Internal review Read more information on this investigation phase

Update

Updated: 6 September 2019

The investigation into the collision with terrain involving a YAK-9UM, VH-YIX, near Latrobe Valley Aerodrome, Victoria on 7 September 2018 is continuing.

ATSB investigators have so far gathered and analysed numerous information resources, and have:

  • analysed radar information and altitude analysis of expected coverage
  • analysed witness video and audio
  • reviewed witness statements
  • reviewed records of the pilot’s training and conversion to warbird aircraft
  • reviewed aircraft maintenance, logbooks and other documentation
  • conducted a technical analysis of the rudder and canopy
  • attempted recovery of digital information from compromised mobile phone.

The investigation is currently in the internal review phase. During this phase, the draft investigation report undergoes a rigorous internal review process to ensure it adequately and accurately reflects the evidence collected, analysis, and agreed findings of the Safety Factor Review.

If the review identifies any issues with the report, such as information that needs to be expanded or findings that need to be modified, investigators will look to collect new evidence or conduct additional examination and analysis of existing evidence.

Once the internal review phase is complete, a draft of the final report will be sent to all directly involved parties for their comment before the report is finalised and published.

Currently, the anticipated completion and publication release date of the final report is during the fourth quarter of 2019. However, should any critical safety issues be identified during any phase of this investigation, the ATSB will immediately notify those affected and seek safety action to address the issue.

 

Preliminary report

Preliminary report published: 15 November 2018

What happened

On 7 September 2018, a Yakovlev Aircraft Factories YAK-9UM aircraft, registered VH-YIX (Figure 1), was being operated on a private flight from Latrobe Regional Airport, Victoria. The pilot/owner of the aircraft was the sole occupant.

The aircraft departed the airport at about 1425 Eastern Standard Time.[1] Recorded air traffic control data showed that the aircraft initially tracked from the airport to the west toward Morwell, climbing to about 2,600 ft and heading north-west near Moe.

Several witnesses described seeing the aircraft conducting aerial manoeuvres to the north of Moe and video footage from a witness showed the aircraft in a steep spiralling dive shortly before it collided with terrain (Figure 2). Other witnesses described seeing the aircraft moments prior to the accident with the engine ‘not revving very loudly’, and ‘making popping noises’. The aircraft was destroyed, and the pilot was fatally injured.

Figure 1: Yakovlev Aircraft Factories YAK-9UM aircraft, registered VH-YIX

Figure 1: VH-YIX. Source: Mike Yeo- jetphotos.net

Source: Mike Yeo- jetphotos.net

Site and wreckage examination

On-site examination of the wreckage and surrounding ground markings indicated that the aircraft impacted terrain in a right-wing low, nose‑down attitude. The tail of the aircraft separated from the fuselage during the accident sequence. Both wings, the forward fuselage and the cockpit were substantially disrupted and compressed from vertical impact forces. An extensive area surrounding the accident site was contaminated with fuel that was released when the wing tanks ruptured. The degree of propeller damage observed on-site was consistent with the engine producing a level of power at the time of impact.

The ATSB recovered a number of components from the accident site for further examination. The aircraft was not equipped with a flight data recorder or cockpit voice recorder, nor was it required to be.

Figure 2: VH-YIX aerial picture of accident site

Figure 2: VH-YIX aerial picture of accident site. Source: ATSB

Source: ATSB

Ongoing investigation

The investigation is continuing and will include consideration of the:

  • pilot’s qualifications, experience and medical history
  • recovered aircraft components
  • maintenance documentation
  • operational documentation
  • witness interviews
  • electronic devices recovered from the aircraft.

 

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The information contained in this 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.

 

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  1. Eastern Standard Time (EST): Coordinated Universal Time (UTC) + 10 hours.
General details
Date: 07 September 2018   Investigation status: Active  
Time: 1433 EST   Investigation level: Defined - click for an explanation of investigation levels  
Location   (show map): 19 km NW, Latrobe Valley Aerodrome (near Moe-Walhalla Road, Tanjil South)   Investigation phase: Final report: Internal review  
State: Victoria   Occurrence type: Collision with terrain  
Release date: 06 September 2019   Occurrence category: Accident  
Report status: Preliminary   Highest injury level: Fatal  
Anticipated completion: 4th Quarter 2019    

Aircraft details

Aircraft details
Aircraft model Yakovlev Aircraft Factories - YAK-9UM  
Aircraft registration VH-YIX  
Serial number 0470409  
Type of operation Private  
Sector Piston  
Damage to aircraft Destroyed  
Departure point Latrobe Valley, Vic.  
Destination Latrobe Valley, Vic.  
Last update 06 September 2019