Definition
A coiled spring formed into a continuous ring, used to apply uniform inward radial pressure around a shaft. In aircraft engines, it is most commonly found inside oil seals, where it keeps the sealing lip pressed evenly against the rotating shaft to prevent oil leakage.
Plain English
A small spring shaped like a circle that wraps around a shaft and squeezes evenly all the way around. It is used to keep an oil seal pressed firmly against the shaft so oil cannot leak past it.
Context Anchor
Seen during engine maintenance when inspecting or installing oil seals around rotating engine shafts.
Derivation
Named after a garter — the elastic band worn around the leg to hold up a stocking. The spring works the same way: a ring that grips evenly all the way around.
Why Pilots Care
A damaged or weak garter spring allows oil to escape past the seal, which can lead to low oil pressure or engine damage.
Analogy
Think of a hair tie wrapped around a ponytail — it grips evenly all the way around and keeps everything tight against the center.
Intuition Check
Garter does not refer to clothing here. It means the spring is shaped like a circular band that wraps around a seal and keeps tension on it.
Example Sentence 1
During the seal inspection, the technician checked that the garter spring was still seated correctly inside the lip of the oil seal.
Example Sentence 2
Before reinstalling the propeller, check that the garter spring sits evenly in its groove on the seal.