How does an altimeter determine aircraft altitude?

How does an altimeter determine aircraft altitude?

• A. By measuring speed and direction
• B. By calculating the distance from the ground
• C. By measuring atmospheric pressure
• D. By using GPS data

Answer: (C)

An altimeter determines aircraft altitude by measuring atmospheric pressure. The principle behind this is based on the fact that as an aircraft ascends, the ambient air pressure decreases. This relationship is grounded in the barometric formula, which indicates that atmospheric pressure decreases with an increase in altitude. Altimeters typically use a barometric sensor that detects the current atmospheric pressure and compares it to a standard pressure at sea level (usually defined as 29.92 inches of mercury or 1013.25 hPa). By this comparison, the altimeter can provide a relatively accurate reading of the altitude, since the decrease in pressure correlates with an increase in height above the ground. While GPS can also provide altitude information, it functions differently by determining position using satellites and can be affected by various factors such as signal obstructions. Similarly, measuring speed and direction does not directly relate to altitude but rather to the aircraft's flight path, and calculating the distance from the ground would require a different kind of sensor or technology that is not typically associated with traditional altimeters.

An altimeter determines aircraft altitude by measuring atmospheric pressure. The principle behind this is based on the fact that as an aircraft ascends, the ambient air pressure decreases. This relationship is grounded in the barometric formula, which indicates that atmospheric pressure decreases with an increase in altitude.

Altimeters typically use a barometric sensor that detects the current atmospheric pressure and compares it to a standard pressure at sea level (usually defined as 29.92 inches of mercury or 1013.25 hPa). By this comparison, the altimeter can provide a relatively accurate reading of the altitude, since the decrease in pressure correlates with an increase in height above the ground.

While GPS can also provide altitude information, it functions differently by determining position using satellites and can be affected by various factors such as signal obstructions. Similarly, measuring speed and direction does not directly relate to altitude but rather to the aircraft's flight path, and calculating the distance from the ground would require a different kind of sensor or technology that is not typically associated with traditional altimeters.