BWS Checkride Practice Test

Before takeoff, you must ensure the altimeter reflects the true local pressure and will read the correct height above the airport. The way to do this is to obtain the current altimeter setting from a reliable source—ATC, automated weather like METAR/TAF, or official aviation sources—and dial that value into the altimeter’s window. Then perform a practical cross-check: when you’re on the runway, the altimeter should indicate the airport’s field elevation. This confirms the setting is correct and that your altitude readings will correspond to the actual terrain and traffic environment.

If you can’t obtain a current local setting, you can use standard pressure (29.92), but you should still cross-check against the field elevation and the altimeter indication to ensure the instrument would read correctly with the actual local setting. This cross-check is key to preventing altitude errors that could affect obstacle clearance and separation from other aircraft.