Variometer
In order to stay aloft, your glider has to find lift. That lift comes from different sources and can be measured by the variometer. The variometer senses difference in pressure and displays that difference instantaneously on the face of the instrument. The vane type variometer operates using the principle that air flows from high to low pressure. The system consists of an instrument attached to an outside static source on one side of the vane and to a reference chamber on the other side. When the pressure becomes higher at either position, the air rushes toward the lower pressure. Therefore in an ascent, the outside static source pressure is lower than the reference chamber and airflows from the chamber, across the vane, toward the static source. The vane moves up and since the vane is attached to the needle on the face of the instrument, a climb is indicated. A descent would cause airflow and needle deflection in the opposite direction since pressure in the chamber would be lower than the outside static pressure |
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