apparent altitude的意思|示意

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Apparent altitude is a term that is used in navigation to measure the vertical distance between a ship or aircraft and a selected point on the surface of the earth. It is usually expressed in terms of degrees above the horizon.

Apparent altitude is the vertical angle between a reference line and the line of sight between the point of observation and the point on the surface of the earth. This reference line is usually the horizontal plane of the earth, the water surface, or mean sea level. To measure the apparent altitude of a point, the elevation of the point must first be known.

Apparent altitude is one of the important tools used in navigation, as it helps to identify the location and direction of a vessel with respect to its current position. It also helps to determine the angular distance between two points. It can either be determined by measuring the altitude of the celestial objects or by using navigation instruments like theodolites, sextants, and other devices.

Apparent altitude is also important in aviation, as it allows pilots to calculate their altitude above the terrain, in order to remain clear of obstacles. In addition, it is used in calculating the fuel consumption of an aircraft, the airspeed, and the rate of climb.