Aviation safety investigations & reports

Tail rotor pedal failure and collision with terrain involving Robinson R22 helicopter, VH-HHQ, near Kutchera Station, Queensland, on 22 June 2019

Investigation number:
AO-2019-035
Status: Completed
Investigation completed
Phase: Final report: Dissemination Read more information on this investigation phase

Final Report

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What happened

On 22 June 2019, a Robinson Helicopter Company R22, registered VH-HHQ, departed Kutchera Station, Queensland to perform mustering operations. During mustering, as the pilot was manoeuvring the helicopter, the right tail rotor (or anti-torque) pedal cracked and became stuck. The pilot was unable to dislodge the pedal and prepared for an immediate landing in accordance with the stuck pedal procedure. Just prior to landing, the helicopter struck a tree and became uncontrollable. The aircraft impacted the ground and although the pilot was uninjured, the helicopter was substantially damaged.

What the ATSB found

Following examination of the helicopter by the maintenance organisation, a significant fracture was noted at a weld located on a right angle join between two sections of tube. The right pedal was removed from the helicopter and sent to the ATSB for further examination and testing. The ATSB found that the pedal had fractured as a result of a fatigue failure, which had initiated at the welded joint, and progressed until the remaining section of the tube could no longer sustain the in‑service loads. It was considered likely that a pre-existing crack had initiated at the highest stress part of the component, and had opened up following the load applied during the manoeuvre described by pilot, rendering the pedal unserviceable.

The tail rotor pedal had been recently inspected as part of routine maintenance and while it was considered likely that the developing crack was present, it was not detected at that inspection. However, it was considered that this was due to the inherent difficulties associated with inspections at the location of the cracking.

What has been done as a result

While not required as part of the routine inspections, the maintenance organisation has added the tail rotor pedals to the list of components that undergo magnetic particle inspection at each 2,200‑hour overall.

Safety message

The location of the fatigue crack in this accident highlighted the need to be vigilant when performing inspections in difficult or hard to reach places. In the case of the tail rotor pedal, the inspection was made difficult due to the location, and required a torch and mirror to inspect a matte black surface.

Additionally, the quick thinking actions of the pilot following the failure resulted in a good outcome, with no injuries reported.

Download final report
[Download  PDF: 429KB]
 
 
 

The investigation

General details
Date: 22 June 2019   Investigation status: Completed  
Time: 0900 EST   Investigation level: Short - click for an explanation of investigation levels  
Location   (show map): Kutchera Station, near Abingdon Downs   Investigation phase: Final report: Dissemination  
State: Queensland   Occurrence type: Collision with terrain  
Release date: 08 September 2020   Occurrence category: Accident  
Report status: Final   Highest injury level: None  

Aircraft details

Aircraft details
Aircraft manufacturer Robinson Helicopter Co  
Aircraft model R22  
Aircraft registration VH-HHQ  
Serial number 4071  
Operator Northeast Helicopters  
Type of operation Aerial Work  
Sector Helicopter  
Damage to aircraft Substantial  
Departure point Kutchera Station, Queensland  
Destination Kutchera Station, Queensland  
Last update 08 September 2020