Private Pilot Private Exam

If a pilot does not adjust the altimeter when transitioning from low pressure to high pressure, what will happen?

1. The altimeter will indicate lower than actual altitude

2. The altimeter will indicate correct altitude

3. The altimeter will indicate higher than actual altitude

4. The altimeter will become inoperable

The correct answer is: The altimeter will indicate lower than actual altitude

When a pilot transitions from a low pressure area to a high pressure area without adjusting the altimeter, the altimeter fails to reflect the actual change in atmospheric pressure. Altimeters are calibrated to read the correct altitude based on the surrounding air pressure. In a low pressure environment, the atmosphere is less dense, causing the altimeter to read a lower altitude. When moving to a high pressure environment, the density of the air increases, resulting in actual altitude being higher than what is indicated by the unadjusted altimeter. Therefore, if the pilot does not make the adjustment, the altimeter will indicate a lower altitude than the aircraft's actual altitude, potentially leading to dangerous situations if the pilot believes they are flying at a safe altitude when they are actually much higher. This understanding is critical for maintaining safe navigation and awareness during flight, as incorrect altimeter settings can result in significant altitude discrepancies, particularly during takeoff and landing phases.