Definition
A small opening, flush with the aircraft's outer skin, that admits undisturbed ambient air pressure into the static pressure system. The static hole feeds the static line that supplies pressure to the altimeter, vertical speed indicator, and airspeed indicator.
Plain English
A small hole on the side of the aircraft that lets the surrounding air pressure into the instruments, so they can measure altitude, climb rate, and airspeed correctly.
Context Anchor
Seen in pitot-static system diagrams, instrument system descriptions, and during preflight checks for blocked openings.
Derivation
Static' comes from the Latin 'staticus,' meaning standing still. The hole is called 'static' because it samples air that is not moving relative to the aircraft -- it captures the still, ambient pressure rather than the rushing air pressure caused by forward flight.
Why Pilots Care
Blockage or icing of the static hole causes incorrect altitude, airspeed, and vertical speed indications, directly affecting safe flight and instrument approaches.
Grounding Statement
The static hole is where the aircraft samples the outside air pressure it needs for basic instrument readings.
Intuition Check
Static does not mean the hole is inactive or unused here. It means the hole is used to sense surrounding air pressure rather than pressure from forward motion.
Example Sentence 1
During preflight, the pilot checked that the static hole on the side of the fuselage was clear of debris.
Example Sentence 2
Ice forming over the static hole caused the altimeter to freeze at the wrong altitude.