About the project

  • Date: June, 2022
  • Client: Vector Renewables
  • Category:
  • Address: Stirling, Scotland
Bladestar Renewables Ltd were tasked with a Cat 4 repair to a LM 40.0P blade. The damage was the direct result of a previous failed repair. The damage was located 12m from the root. The crack showing through the topcoat was a 400mm chord ways crack at around 80% chord. This repair took 40 hours to complete via rope access. The repair report was generated and uploaded to our online server for download within 72 hours of repair completion.

Key Points


Investigation was started by removing all surrounding paint in the defective area to see if any other defects were visible.  This would help us in identifying a root cause analysis.  Upon further investigation it was deemed that the old repair had not been sufficiently overlapped.  There was also only one layer of fibreglass on the old repair.  This was not sufficient and 4 layers should have been used to ensure structural integrity. 


We removed the defective fiberglass to expose the core.  A core replacement had been completed however poor workmanship of the replacement had left the area too fragile to withstand the stress load requirements.  The glue joins in the core replacement were also out of spec and deemed excessive. 

Once the core was removed it was found that the wrong fiberglass had been used under the core resulting in debunking from the inner shell.  We removed the defective core and replaced with fresh core following our work instruction.  This was then overlapped with the correct amount of fibreglass for the area. 

We then structurally profiled the area in preparation for filling and painting.  When the repair was finished we had successfully completed a 1.3 metre core replacement with internal shell bonding and a 1.5m x 0.6m reinforcement lamination.