Definition
A repair to a metal aircraft component, tank, or skin in which a piece of compatible metal is fused into place by welding to restore strength, seal a leak, or close a damaged area. Welded patches are used on items such as exhaust stacks, engine mounts, and fuel or oil tanks, and must be made using approved welding methods, filler material, and procedures that match the parent metal.
Plain English
A patch fixed in place by melting metal at the join so the patch and the original part fuse into one solid piece.
Context Anchor
Seen in aircraft maintenance records, repair instructions, and inspections of metal parts such as steel tube structures, tanks, or other weldable components.
Derivation
From 'weld' (Old English/Germanic origin, meaning to join metals by heat) and 'patch' (a piece used to cover or repair a hole). Together: a repair piece that is permanently fused, not bolted or riveted.
Why Pilots Care
Restores structural integrity so the aircraft can safely carry flight loads without risk of failure.
Intuition Check
Do not think of a welded patch as a temporary cover or a stick-on repair. In aircraft maintenance, it is a permanent metal repair joined by welding.
Example Sentence 1
The mechanic installed a welded patch on the cracked exhaust stack and pressure-tested it before returning the aircraft to service.
Example Sentence 2
After completing the welded patch, the technician performed a dye-penetrant inspection to confirm the joint was sound.