Which altitude is indicated when the altimeter is set to 29.92 inHg?

Which altitude is indicated when the altimeter is set to 29.92 inHg?

• A. Density.
• B. Indicated altitude.
• C. Pressure.
• D. Standard altitude.

Answer: (C)

When you set the altimeter to 29.92 inHg, you’re using the standard pressure reference. The instrument then shows the pressure altitude—the altitude in the International Standard Atmosphere that would produce the same pressure you’re seeing. In other words, the reading is a height derived from pressure using the standard atmosphere, not the true height above mean sea level and not adjusted for temperature (density altitude) or for local pressure settings (indicated altitude). This is why the reading reflects a pressure-based altitude.

When you set the altimeter to 29.92 inHg, you’re using the standard pressure reference. The instrument then shows the pressure altitude—the altitude in the International Standard Atmosphere that would produce the same pressure you’re seeing. In other words, the reading is a height derived from pressure using the standard atmosphere, not the true height above mean sea level and not adjusted for temperature (density altitude) or for local pressure settings (indicated altitude). This is why the reading reflects a pressure-based altitude.