§27.1327 Magnetic direction indicator

(a) Except as provided in sub-paragraph (b): (1) Each magnetic direction indicator must be installed so that its accuracy is not excessively affected by the rotorcraft’s vibration or magnetic fields; and (2) The compensated installation may not have a deviation, in level flight, greater than 10° on any heading. (b) A magnetic non-stabilised direction indicator may deviate more than 10° due to the operation of electrically powered systems such as electrically heated windshields if either a magnetic stabilised direction indicator, which does not have a deviation in level flight greater than 10° on any heading, or a gyroscopic direction indicator, is installed. Deviations of a magnetic non-stabilised direction indicator of more than 10° must be placarded in accordance with CS 27.1547 (e).