A previous owner had done a repair to a hole in the fiberglass nacelle. Looks like they used some sort of putty rather than a repair with fiberglass. Recently the hole propagated to the outside surface so a more permanent repair is needed.
I removed the cracked paint on the outside surface and did some sanding.
Exterior:
Interior:
Shop temperature was 23degC and 52% humidity. I applied 3 layers of BID fiberglass cloth to the interior.
I applied 2 layers of BID fiberglass cloth to the exterior.
Next up sanding and painting after the patch cures.