Mooring triangle
The landing triangle or Abschiebedreieck is an auxiliary device for technical drawing or for draft -Drawings, mostly when it comes to the parallel moving lines. It is often used with rulers or in pairs - e.g. B. two right triangles of similar size. Common corner angles are 45 ° -45 ° -90 ° and 30 ° -60 ° -90 °.
On the hypotenuse , the triangle has a scale (sometimes also with a vernier ) with which one of the rulers can be shifted by small, precisely measurable amounts. The inclined sliding angle increases the possible accuracy to better than 0.1 mm.
Such triangles are used, for example, for precise, subsequent dimensioning on technical plans and for the representation of parallel lines such as wall thicknesses , cross-sections of lines , narrow traffic routes . They are also an economical alternative for minor mappings (few measuring points) or reworking (see coordinatograph ), as well as for additions after automatic plotting of a recording.
For parallel shifting of lines on maps, especially maps for aviation and shipping, the push-off triangle is part of the nautical equipment .