Definition
A composite manufacturing process in which dry reinforcing fibers are placed into a closed two-part mold, after which liquid resin is pumped or drawn under pressure into the mold to saturate the fibers. The resin then cures, producing a finished composite part with a smooth surface on both sides.
Plain English
A way of making composite aircraft parts where dry fabric or fiber is laid into a mold, the mold is closed, and liquid resin is then forced in to soak the fibers. Once the resin hardens, the part is finished.
Context Anchor
Seen in composite aircraft manufacturing, maintenance manuals, and repair discussions for molded parts such as fairings, panels, covers, and structural pieces.
Derivation
From 'resin' (the liquid plastic that hardens to bind the fibers), 'transfer' (moving the resin from a reservoir into the mold), and 'molding' (forming the part inside a shaped cavity). The name describes the process directly: resin is transferred into the mold rather than being applied to the fibers beforehand.
Why Pilots Care
Many modern aircraft components are built using this method. Knowing the process helps pilots and owners understand why composite parts have the finish, strength, and repair characteristics they do, and why damage assessment differs from metal parts.
Intuition Check
Resin Transfer Molding is not simply gluing finished parts together. The liquid resin is moved into dry material inside a closed mold, then hardened to create the part.
Example Sentence 1
The aircraft's wingtip fairings were produced using resin transfer molding, which gave both surfaces a clean factory finish.
Example Sentence 2
During inspection the mechanic confirmed the cowling panel had been produced with resin transfer molding rather than hand layup.