Indicated altitude is

• A. The altitude read directly from the altimeter (uncorrected) when it is set to the current altimeter setting.
• B. The altitude corrected for temperature effects.
• C. The altitude above mean sea level after applying corrections.
• D. The altitude read from GPS.

Answer: (A)

Indicated altitude is the altitude shown on the altimeter when it is set to the current local altimeter setting. That reading is uncorrected for nonstandard temperature or instrument errors, and it represents height above mean sea level given the present pressure setting. If you need the true altitude, you would apply a temperature correction (since actual air temperature affects the actual height). GPS altitude, while useful, provides a different measurement and is not the indicated altitude.