Jump to Content
Download final report
[ Download PDF: 199KB]

On 10 November 2016, a Sikorsky S-92A helicopter, registered VH-ZUQ, was scheduled to depart from Broome Airport, WA. During the start procedure, the flight crew reported feeling abnormal vibrations in the airframe. A member of the ground crew then showed the pilots an anti-flap stop that had broken off the main rotor head. Further inspection revealed that two anti-flap stops had been sheared off the main rotor head during start-up.

The anti-flap stop failure was a result of the collective not being lowered at the appropriate point during the start procedure. Several factors were found to have contributed:

  • A series of events resulted in the flight crew having more tasks to complete than originally planned, and less time in which to complete them. This resulted in time pressure on the crew.
  • The PM's unfamiliarity with the unique starting procedures in the S-92A compared with other helicopters contributed to the collective not being lowered in time.
  • The operator's standard operating procedures did not require any call outs for the lowering of the collective, which probably contributed to the collective not being lowered in time.

As a result of this serious incident, the operator conducted its own investigation, and produced 17 recommendations, including:

  • a review pf S-92A start procedures
  • more emphasis placed on the importance of lowering the collective within the engine start procedures
  • a review of certain aspects of flight preparation that contributed to the time pressure experienced.

This incident is an example of what can occur when pressure associated with on-time departures is compounded with the absence of clear operating procedures. It is important that pilots have detailed and specific instructions on which to fall back when they feel pressure beginning to build.

Part of Aviation Short Investigations Bulletin - Issue 60

Download final report
[ Download PDF: 199KB]

Read report

General details
Date: 10 November 2016 Investigation status: Completed 
Time: 12:15 WST  
Location   (show map):Broome Investigation type: Occurrence Investigation 
State: Western Australia Occurrence type: Propeller/rotor malfunction 
Release date: 24 May 2017 Occurrence class: Operational 
Report status: Final Occurrence category: Serious Incident 
 Highest injury level: None 
Aircraft details
Aircraft manufacturer: Sikorsky Aircraft 
Aircraft model: S-92A 
Aircraft registration: VH-ZUQ 
Serial number: 920205 
Type of operation: Charter 
Sector: Helicopter 
Damage to aircraft: Minor 
Departure point:Broome, WA
Destination:Lombadina, WA
Share this page Provide feedback on this investigation
Last update 24 May 2017