Plain English Meaning

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.

Full 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 when set to the , the reads zero or shows known error, the reads zero, and the and respond correctly during .