Definition
A manufacturing process in which a measured amount of raw material — typically a thermoset plastic, composite, or rubber compound — is placed into the open cavity of a heated mold, then shaped by closing the mold under high pressure until the material cures into its final form.
Plain English
A way of making parts by squeezing softened material between two heated mold halves until it hardens into the shape of the mold.
Context Anchor
Seen in aircraft materials, maintenance, and manufacturing discussions for molded plastic, rubber, or reinforced aircraft parts.
Derivation
Compression comes from the Latin 'comprimere,' meaning 'to press together.' Molding refers to shaping material in a form. Together, the term describes shaping a part by pressing it into a mold — which is exactly what happens.
Why Pilots Care
Many aircraft components — interior panels, fairings, radomes, and certain composite structural parts — are produced this way. Knowing the process helps when reading repair manuals or understanding why a damaged part may need factory replacement rather than field repair.
Intuition Check
Do not confuse compression molding with engine compression. Here, “compression” means using pressure to press material into a mold, not squeezing fuel-air mixture in a cylinder.
Example Sentence 1
The cowling fairing was produced by compression molding, which is why its shape is consistent across every aircraft in the fleet.
Example Sentence 2
Maintenance crews ordered replacement fairings produced through compression molding to match the original factory parts.