Visual navigation

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Visual navigation is a method of orienting oneself in the airspace , which is mainly used by pilots of small aircraft flying under visual flight conditions.

The navigating by sight, so to compare the map with the terrain, requires flying by initially provide itself with appropriate maps. For the needs of aviation for visual meteorological conditions (Engl. Visual flight rules , VFR) there are special maps, the content by the ICAO (International Civil Aviation Organization) in 1949 was standardized.

ICAO card and special cards

The standard map for VFR aviation is the ICAO map on a scale of 1: 500,000. Here 1 cm on the map corresponds to 5 km in nature, what

  • on the one hand still gives a sufficient overview,
  • on the other hand , enables a good representation of waters and important traffic routes (railways, motorways, federal highways), towns and forest areas .
  • Landmarks such as television towers, churches and high-rise buildings (which are always drawn in from a height of 100 m ), as well as observation towers, road or railroad crossings are also helpful for orientation at low altitudes .

Due to the lower flight altitude, there are also individual special maps for gliding on a scale of 1: 200,000 to 1: 300,000, which show the terrain more precisely, but also all cable cars and other aviation obstacles below 100 m height.

For areas without modern navigation aids , large-scale approach maps of the airport surroundings should also be mentioned, and for long-haul flights so-called route maps on a scale of 1: 1 million or smaller.

Complementary navigation methods

Visual navigation is primarily used by private pilots . It is of little importance in scheduled flights. In general, the view navigation is supported by other methods - mainly radio navigation and / or GPS -assisted satellite navigation . The sense of space (sense of balance and " sitting meat "), the dead reckoning and various approach aids in the vicinity of airports are also important .

From an altitude of around 5 km, visual navigation becomes less important because the visibility of the air reduces the contrast of the terrain. Line structures such as wide streets or rivers , on the other hand, can still be seen from a great height, which is due to a special characteristic of the eye .

Visual navigation in everyday life

Even if we are seldom aware of it: movement as a pedestrian , cyclist or driver is ultimately based on visual navigation. However, if you lose your orientation you can stop and find your way again. If you "in an aircraft verfranzt " - about by the advent of cloud or a few minutes of inattention , the re-orientation can be difficult despite correctly oriented map.