Textron Aviaiton has released Communiqué # ME-TP-005 August 2017. Full documentation can be found here.
ATA 20 – Ballast – Engine and Propeller Removed
All During regular maintenance there are times that removal of the propellers and engines is required. This configuration leaves the airplane in a tail heavy condition causing concerns that the tail would settle; especially if the airplane is undergoing other maintenance requiring maintenance personnel to enter and exit the airplane. This is also concerning if the airplane is on jacks. Textron Aviation recommends that ballast be added to the engine truss to replace the weight removed. This can be sand bags or a weight that bolts to the engine truss as shown in the picture below. There is no part number for this device as this is a shop aid and it can be made locally. The amount of weight used should be the same as the weight that was removed and can vary depending on which King Air is used. Using a tail stand is also recommended. Refer to King Air Communiqué 2016-04 for more information about the use of a tail stand.
ATA 34 – Magnetometer Relocation Kit
434-3013-0001 on Fusion Equipped King Airs B200GT, B200CGT, B300, B300C Kit 434-3013-0001 was released to resolve attitude roll over and heading drift issues on the Electronic Standby Instrument System (ESIS) on Fusion equipped King Airs. The kit relocated the ESIS magnetometer from the aft canted bulkhead to the rear of the tail cone to distance it from large magnetic influences. Several aircraft which have had the kit installed have reported that the heading still drifted. It was discovered on these installations that tail cone variances could allow the bottom of the magnetometer to contact structure. This contact could create vibration in flight that can affect magnetometer performance. The kit has now been revised to address the clearance issue. The revision to the kit includes an optional additional spacer (130-340687-0023) to prevent magnetometer contact with the tail cone. If you are experiencing an anomaly with ESIS heading issues as described above, or when maintenance/inspections are being performed in the tail cone, ensure that there is a minimum of .06” clearance, as shown below. If clearance is not present or heading issues are continuing, please contact technical support at email@example.com for resolution.