Select your product to confirm this information applies to you
(2013) Service Advisory 1336 Rev A: G1000-equipped King Air Temporary Heading Failure
AFFECTED PRODUCTS
G1000 Integrated Flight Deck Systems installed in Beechcraft King Air models are affected.
DESCRIPTION
Through the investigation of temporary heading failure incidents, Garmin has discovered a prominent tendency for the gradual magnetization of aircraft structural components to occur proximate to the GMU 44 magnetometer mounting location in G1000-equipped King Air aircraft. This magnetization is caused by the inappropriate accumulation of precipitation static (p-static) due to inadequate bonding of grounding straps and/or static wicks located in and/or on the empennage.
NOTE: Aircraft that have been repainted may be likely candidates for improper bonding of grounding straps and/or static wicks.
RESOLUTION
Follow aircraft maintenance manual instructions for inspection and maintenance of all grounding straps and static wicks, particularly those located in or on the empennage. Dissipation of p-static provided through properly bonded grounding straps and static wicks is required to prevent disruptive magnetization of airframe components.
If inadequate bonding of grounding straps and/or static wicks is discovered and repaired during inspection of the empennage, Garmin recommends degaussing of any magnetized airframe components, particularly at the base of the rudder and near the GMU 44, followed by a magnetometer calibration in accordance with the applicable Garmin G1000 System Maintenance Manual.