Definition
A strong, waxed cord used to stitch fabric covering to the wing ribs of a fabric-covered aircraft, holding the fabric tightly against the rib structure so it cannot lift away under flight loads.
Plain English
A tough, waxed string used to sew the fabric skin of a wing onto each rib, so the fabric stays pulled down and won't balloon up when the airplane is flying.
Context Anchor
Seen in maintenance of fabric-covered aircraft, especially during covering, inspection, or repair of wings, tail surfaces, and control surfaces.
Derivation
From 'rib' (the curved structural member that gives the wing its shape) and 'lacing' (from Old French 'lacier,' to bind or tie with cord). The name describes exactly what the cord does: it laces the fabric to the ribs.
Why Pilots Care
Secure rib lacing keeps the fabric smooth and attached in flight, preserving wing shape, lift, and structural integrity.
Analogy
It is like stitching fabric onto a frame so the fabric cannot flap loose when air moves over it.
Intuition Check
Rib here does not mean a bone; it means an internal aircraft support. The cord is not decorative—it is part of how the fabric covering is held securely to the aircraft structure.
Example Sentence 1
After applying the fabric to the wing, the technician used rib lacing cord to stitch the covering tightly to each rib.
Example Sentence 2
Before flight, the pilot checked that all rib lacing cord remained tight and undamaged.