If there is a hole with jagged edges protruding inward, what type of patch should be used?

If there is a hole with jagged edges protruding inward, what type of patch should be used?

• A. Box patch
• B. Soft patch
• C. Duct patch
• D. Ring patch

Answer: (A)

When a hole has jagged edges that protrude inward, you want a patch that can grab onto those interior edges and provide a stable, load-distributing seat around the opening. A box patch is designed for exactly this situation: it includes a frame or “box” that fits into the hole and bears on the interior edge, giving a solid surface for the patch to seal against. This setup prevents the patch from catching on the jagged edges and helps maintain a tight, secure seal when fastened. Soft patches are more for small, smoother openings and may not hold well against rough, inward-edged holes. Duct patches are meant for ductwork or smaller penetrations in non-hull material and aren’t suited to irregular hull edges. Ring patches rely on a clean, circular opening with a surrounding ring to clamp onto; jagged inward edges won’t seat well with a ring patch, so the box patch is the better choice here.

When a hole has jagged edges that protrude inward, you want a patch that can grab onto those interior edges and provide a stable, load-distributing seat around the opening. A box patch is designed for exactly this situation: it includes a frame or “box” that fits into the hole and bears on the interior edge, giving a solid surface for the patch to seal against. This setup prevents the patch from catching on the jagged edges and helps maintain a tight, secure seal when fastened.

Soft patches are more for small, smoother openings and may not hold well against rough, inward-edged holes. Duct patches are meant for ductwork or smaller penetrations in non-hull material and aren’t suited to irregular hull edges. Ring patches rely on a clean, circular opening with a surrounding ring to clamp onto; jagged inward edges won’t seat well with a ring patch, so the box patch is the better choice here.