Pressure altitude is defined as the height above mean sea level at a given barometric pressure under standard conditions when the altimeter is set to

Pressure altitude is defined as the height above mean sea level at a given barometric pressure under standard conditions when the altimeter is set to

• A. 29.92 inHg
• B. 30.00 inHg
• C. 28.92 inHg
• D. 1013.25 mb

Answer: (A)

Pressure altitude is the altitude indicated when the altimeter is set to the standard pressure value of 29.92 inHg (1013.25 mb). This standard setting ties the instrument to a standard atmosphere, so the reading reflects height above mean sea level under those conditions and allows flight levels and performance comparisons to be made independent of local pressure variations. Among the options, the canonical standard setting is 29.92 inHg; 1013.25 mb is the same pressure in metric units, but the question asks for the setting in inches of mercury, making 29.92 inHg the best choice.

Pressure altitude is the altitude indicated when the altimeter is set to the standard pressure value of 29.92 inHg (1013.25 mb). This standard setting ties the instrument to a standard atmosphere, so the reading reflects height above mean sea level under those conditions and allows flight levels and performance comparisons to be made independent of local pressure variations. Among the options, the canonical standard setting is 29.92 inHg; 1013.25 mb is the same pressure in metric units, but the question asks for the setting in inches of mercury, making 29.92 inHg the best choice.