Definition
A pre-takeoff verification, performed during the run-up or taxi phase, in which the pilot confirms that flight instruments are reading correctly and responding appropriately. This typically includes checking that the attitude indicator shows the correct pitch and bank, the heading indicator is set and matches the magnetic compass, the altimeter reads field elevation within tolerance when set to the local altimeter setting, the vertical speed indicator reads zero or shows known error, the airspeed indicator reads zero, and the turn coordinator and inclinometer respond correctly during taxi turns.
Plain English
A check, done before takeoff, to make sure each cockpit instrument is showing the right reading and reacting properly before the airplane leaves the ground.
Context Anchor
Used after engine start, during taxi, and during the run-up before takeoff.
Derivation
Instrument comes from a Latin word meaning “to equip.” In aviation, instruments are the equipment that show the pilot what the airplane and engine are doing. Check means to verify something before relying on it.
Why Pilots Care
Confirms that attitude, heading, and turn information is reliable, reducing the risk of spatial disorientation or navigation errors once airborne.
Intuition Check
An instrument check is not just a quick glance at the panel. It is a deliberate confirmation that the indications are believable and behaving correctly.
Example Sentence 1
During taxi, the pilot completed the instrument check by verifying the heading indicator matched the magnetic compass and the turn coordinator deflected correctly in each turn.
Example Sentence 2
During the run-up, the pilot completed an instrument check by comparing the magnetic compass heading with the heading indicator after a 180-degree turn on the taxiway.