Yawing of wind turbine nacelle placed ship in line of fire
- Safety Flash
- Published on 13 September 2021
- Generated on 8 December 2025
- IMCA SF 25/21
- 2 minute read
What happened?
A wind turbine started yawing, placing an approaching vessel in the line of fire. A turbine nacelle had been confirmed as locked on requested heading and permission had been given for the vessel to enter the turbine safety zone. The vessel entered the safety zone, connected, transferred technicians to the turbine via walk-to-work gangway, then completed cargo transfer to the transition piece (TP) using the ship’s crane.
The vessel then moved off from the TP and was about to start moving astern (in the direction of current flow) when it was noted that the nacelle heading was about 50 degrees different to that requested, with a turbine blade directly in the vessel’s intended path. The move was cancelled and the ship moved ahead, away from the blade disk, on DP joystick auto-heading. The safety zone was exited without further event.
The wind turbine nacelle started yawing, placing an approaching vessel in the line of fire
What went wrong?
The new, oncoming crew on the turbine tower yawed the nacelle using local controls, assuming that the vessel had moved clear, not considering the time taken to complete cargo operations.
There was no communication with the bridge or client crew before starting the move.
What were the causes?
- Lack of situational awareness
- Failure to follow established communication protocols
Actions
- Operator’s procedures were reviewed and teams reminded of the requirement to receive positive confirmation that vessels are clear before moving the nacelle.
- As engineering-based Lockout/Tag-out controls are not practicable, procedural/administrative controls were made more robust.
- Operator’s communication protocols were strengthened and communicated.
- Reminder stickers ‘WAIT FOR GREEN LIGHT BEFORE YAWING’ were placed on all control boxes.
Related Safety Flashes
-
IMCA SF 10/21
8 April 2021
IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.
The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.
All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.
IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.
The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.
Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.