Service Bulletins

Service Bulletin 34-4163: Navigation – Static System Improvement

Issued: June 2016

Effectivity: Model King Air C90GTi, serial numbers LJ-1847, LJ-1848, LJ-1853 through LJ-2059, LJ-2061 through LJ-2126.

Compliance – Recommended: This service bulletin should be accomplished at a scheduled maintenance period or inspection. A service bulletin published by Textron Aviation may be recorded as completed in an aircraft log only when the following requirements are satisfied: 1) The mechanic must complete all of the instructions in the service bulletin, including the intent therein. 2) The mechanic must correctly use and install all applicable parts supplied with the service bulletin kit. Only with written authorization from Textron Aviation can substitute parts or rebuilt parts be used to replace new parts. 3) The mechanic or airplane owner must use the technical data in the service bulletin only as approved and published. 4) The mechanic or airplane owner must apply the information in the service bulletin only to aircraft serial numbers identified in the Effectivity section of the bulletin. 5) The mechanic or airplane owner must use maintenance practices that are identified as acceptable standard practices in the aviation industry and governmental regulations.

Reason: A hose in the pilot’s static system has the potential for moisture accumulation in an area that cannot drain.

Warranty: Eligible airplanes may qualify for parts and labor coverage to the extent noted in the Labor Hours and Material Availability sections of the document.

Labor: Modification and Inspection .0 Labor Hours

From King Air Communiqué 2016-05

Issued: May 2016

ATA 20 – Leading Edge Erosion Tape


The King Air leading edges are protected from erosion by a protective tape or abrasion resistant spray coating. Installation procedures for both are found in the King Air Standard Practices Manual (20-08-00-201). This protective tape comes in different widths to fit in the different areas of the airframe.

Editor’s Note: Communiqué 2016-05 has a list that shows the different tapes available from Textron Aviation Parts Distribution (TAPD).

ATA 31 – Fusion Equipped King Air USB Device Requirements

Fusion equipped King Airs require periodic database and software updates. On airplanes without the IMS 3500 system, this is performed through the USB port on the AFD 3700 displays. The port on the AFD 3700 is compliant to USB 2.0 standards. The Rockwell Collins airplane maintenance manual excerpt shown below, currently calls for a USB 2.0 or equivalent device formatted with FAT 32. Collins has provided additional clarification that a version 3.0 USB device is an acceptable equivalent as long as it is USB 2.0 compatible and has a capacity between 4Gb and 32Gb. Collins will be adding clarification to the reference below in a future update to the manual.

TASK 31-60-01-470-802
2. reating USB Media
A. ools and Equipment
NOTE: Equivalent item can be used.

Part Number


Commercially Available

Microsoft Windows 7 Personal Computer (PC) with CD-ROM Drive and USB Port

Commercially Available

USB 2.0 Compatible Flash Drive (empty), formatted with FAT 32, 4Gb capacity or larger

ATA 32 – Main Landing Gear Drag Leg “Un-Locking” After Extension


Operators have contacted Textron Aviation Technical Support to report that after approximately 30 minutes or so, the main landing gear drag leg dog bone is moving away from its stop. This gives the impression that the drag leg locking mechanism has become “un-locked”.

During a normal extension of the landing gear, the dog bone contacts the stop to push the landing gear into the down and locked position. When the downlock hooks begin to contact with the lock pin, the dog bone will be in full contact with its stop to complete the movement of the drag leg assembly into the down and locked position, and the downlock hooks will move up and over the lock pin to complete the downlock.

After the hydraulic system turns off, the hydraulic pressure bleeds off. The hydraulic actuator will no longer have the pressure (force) to push the dog bone. The link assembly that connects the dog bone to the downlock hooks has a spring. Due to this spring, the dog bone can move away from its stop as the hydraulic pressure bleeds off. This condition is normal. In this condition, the downlock hooks will remain over the lock pins and keep the drag leg safely in the locked position.

In summary, the dog bone can and does, at times, move away from the stop; as long as the downlock hooks are over the D bolt, it can be considered down and locked. The illustration below shows this condition.

MC KA 2016-05-6From King Air Communiqué 2016-07

Issued: June 2016

ATA 46 – XM Weather TAF data on Pro Line 21 King Airs with XM Receiver part number 822-2031-002

Beginning in early 2016, Rockwell Collins began receiving reports of intermittent reception of Terminal Area Forecast (TAF) data through the XM weather receiver installed in Pro Line 21 aircraft. This data includes products such as METARs and AIRMETs. Investigation deter­mined that the National Weather Service had increased the data package size of these messages and the current configuration of the receiver was causing a software time out and reset before the complete data package was downloaded. Any operators experiencing the issue may utilize Rockwell Collins Service Information Letter (SIL) 523-0824074 to provide an updated receiver configuration allowing it to handle the new data package size. Aircraft with factory installed Fusion avionics are not affected. Pro Line 21 aircraft which have been upgraded to Fusion avionics through an STC may still have the 822-2031-002 receiver and require the update.

The above information is abbreviated for space purposes. For the entire communication, go to

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