Aircraft at A will get erroneous reading while that at B will have no error. Alternatively, A should utilize a beacon located near coast line.
One of the errors in a direction finder resulting from the change in the direction of travel of a radio ground wave as it passes from one medium to another (i.e., from land to sea or from sea to land). Also called land effect, shoreline effect
, and shoulder effect
. This effect can be minimized by use of coastal beacons, in which the
radio beam will leave the coast at 90°, resulting in nil refraction.