Definition
The sealed case that encloses the magnetic compass assembly. It holds the float, the compass card, and the small magnets, and is filled with a clear liquid that dampens movement and supports the float so the card swings smoothly rather than jerking with every motion of the aircraft.
Plain English
The fluid-filled case that holds all the moving parts of the magnetic compass.
Context Anchor
Seen when learning how a magnetic compass is built and when inspecting the compass for leaks, cracks, or air bubbles.
Derivation
From the verb 'house' meaning to enclose or shelter. The housing is what gives the compass parts a protected home.
Why Pilots Care
If the housing leaks or develops a large bubble, the compass card no longer floats correctly and indications become unreliable. Checking the housing is a standard part of preflight.
Intuition Check
Do not think of the compass housing as the panel or mount around the instrument. Here, housing means the sealed body of the compass itself.
Example Sentence 1
During preflight, the pilot noticed a small bubble in the compass housing and noted it for the mechanic.
Example Sentence 2
Bubbles inside the compass housing indicate the fluid level is low and need to be addressed.