coefficient D

coefficient D

[¦kō·ə′fish·ənt ′dē]
(navigation)
A component of magnetic compass deviation, varying with the sine function of twice the compass heading, resulting from induced magnetism in all symmetrical arrangements of the craft's horizontal soft iron.

coefficient D

A quadrantal deviation in a compass caused by temporary magnetism induced in the body of the carrying aircraft by the presence of soft iron in the load or the equipment carried. The maximum effect of coefficient D occurs on intercardinal headings (i.e., NE, SE, SW, and NW). Coefficient D = ¼{(Deviation on NE + Deviation on SW) − (Deviation on NW + Deviation on SE)}.