The Vertical Speed Indicators (V.S.I., also sometimes called a Variometer), senses changing air pressure, and displays that information to the pilot as a rate of climb or descent in feet per minute (displayed above as Hundreds of FPM), meters per second or knots. The Vertical Speed Indicators (VSI) flight instrument measures the vertical speed (vertical velocity / rate of climb). …
[...]All posts in Instruments
Compasses
The Heading Indicator (also known as the Directional Gyro, or DG; sometimes also called the gyrocompass or compass though usually not in aviation applications) displays the aircraft’s heading with respect to geographical north. Principle of operation is a spinning gyroscope, and is therefore subject to drift errors (called precession) which must be periodically corrected by calibrating the instrument to …
[...]Altimeters
The Altimeter shows the aircraft’s height (usually in feet or meters) above some reference level (usually sea-level) by measuring the local air pressure. It is adjustable for local barometric pressure (referred to sea level) which must be set correctly to obtain accurate altitude readings. This requires the altimeter to be set prior to every flight, and during flight as …
[...]Airspeed Indicators
The airspeed indicator or airspeed gauge is an instrument used in an aircraft to display the craft’s airspeed, typically in knots, to the pilot. The Airspeed Indicators shows the aircraft’s speed (usually in knots) relative to the surrounding air. It works by measuring the ram-air pressure in the aircraft’s pitot tube. The indicated airspeed must be corrected for air density (which varies with altitude, temperature and humidity) in …
[...]