Definition
The complete saturation of a reinforcing fabric (such as fiberglass, carbon fiber, or Kevlar cloth) with liquid resin during the layup of a composite structure, so that every fiber is fully coated and no dry spots or air pockets remain.
Plain English
Soaking the cloth fully with resin so it is wet all the way through, with no dry patches.
Context Anchor
Seen in aircraft composite repair, fiberglass work, fabric covering, and other maintenance tasks where cloth or fibers are bonded with a liquid material that later hardens.
Derivation
A straightforward compound term: the cloth is being made fully 'wet' with resin, and 'out' indicates the saturation is complete — wet all the way through, not just on the surface.
Why Pilots Care
A poor wet-out leaves dry fibers or air voids in the laminate, which significantly weakens the finished part. For pilots and owners overseeing composite repairs, knowing whether a layup was properly wetted out is a basic quality check on structural integrity.
Intuition Check
Wet-out does not mean the part is wet with water. Here it means the bonding liquid has fully soaked into the cloth or fibers.
Example Sentence 1
The technician worked the resin into the fiberglass with a brush and roller until full wet-out was achieved.
Example Sentence 2
Incomplete wet-out left dry spots that weakened the repaired composite panel.