What does a pressure altimeter convert atmospheric pressure data into?

A pressure altimeter functions by measuring the atmospheric pressure surrounding the aircraft and, through a standardized formula, it converts this pressure data into height above mean sea level (MSL). The relationship is based on the principle that as altitude increases, atmospheric pressure decreases. By referencing a preset atmospheric pressure, known as the standard pressure (usually 29.92 inches of mercury), the altimeter can indicate how high the aircraft is flying compared to sea level.

This process is crucial for pilots because it allows them to maintain safe altitudes, avoid terrain, and manage air traffic effectively. The ability of the altimeter to provide a readout of height in feet is essential for navigation and overall flight operations. As such, this makes the conversion of atmospheric pressure into altitude in feet the correct function of a pressure altimeter.