Service Bulletin SB-10, Revision A

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Procedures specified in this service bulletin must be accomplished in accordance with accepted methods of aircraft

maintenance and applicable government regulations. Appropriate log book entries must be made.

COPYRIGHT © 2020

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I. SUBJECT

This service bulletin addresses material defects found in some of the extruded material used in McFarlane Aviation, Inc (McFarlane). aileron hinge assembly, P/N: MC0523816-1. An inspection method to identify the defective material and the corrective actions are given in this document. The affected aileron hinge is used in Cessna aircraft models 150, 152, 170, 172, 175, 180, 182, 185, 205, and 210. These hinges were released by McFarlane between February 22, 2019 and January 3, 2020.

II. BACKGROUND

McFarlane PMA aileron hinge assembly, P/N: MC0523816-1 is used at three locations along each aileron control surface to attach it to the aircraft wing (see Figure 1 below).

Figure 1 - Aileron Hinge Locations

The McFarlane aileron hinge assembly is created from three subcomponents, two unique hinge halves and a hinge pin. During production the three components are matched-fit with pins of various diameters. This reduces the gap between components and thus increases the life of the hinge assembly. Due to this design attribute the subcomponents are not interchangeable.

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Service Bulletin 10, Revision A

Each hinge half is machined from extruded aluminum hinge stock. For the purpose of inspection, the hinge half features are defined as follows:

Figure 2 - Hinge Design Features

III. AFFECTED AIRCRAFT

The McFarlane hinge, P/N: MC0523816-1, is eligible for installation on the following Aircraft:

 

 IV. AFFECTED PARTS

Affected McFarlane aileron hinges are P/N: MC0523816-1, shipped between February 22, 2019 and January 3, 2020. The production lots for these parts are JO55493, JO55519, JO56823, JO57775, & JO60003.

V. IDENTIFICATION METHODS

Aircraft service records for aircraft listed in Section III of this document must be reviewed to determine if a McFarlane aileron hinge from the affected part list has been installed. If the affected aileron hinges have been installed, the hinges must be inspected per section VII instructions. If aircraft service records show the aileron hinges have not been installed or purchased between the dates of February 22, 2019 and January , 2020, or were replaced with non-McFarlane parts, this service bulletin is not applicable. This service bulletin is applicable to all hinges purchased between February 22, 2019 and January 3, 2020.

Figure 3 - Example Laser Etched Hinge Marking

Note: In an unpainted state, McFarlane aileron hinges are anodized and appear gold in color. Further, the aileron hinge marking most likely appears on the riveted half of the hinge and will be obscured when installed. In most cases, the aircraft service records will be needed to determine if an affected aileron hinge has been previously installed. This service bulletin must be considered applicable to any hinges purchased between February 22, 2019 and January 3, 2020 and not installed.

VI. COMPLIANCE

Disassembly and inspection of the McFarlane aileron hinge is mandatory and must be completed within the next 25 hours time-in-service (TIS) after February 7, 2020 or within the next 6 months after February 7, 2020, whichever comes first if the aileron hinge is one of the lots listed in section IV of this service bulletin.

If the inspection identifies extrusion cracks or delamination of the hinge bulb, immediate replacement of the hinge is required prior to further flight.

The requirements of Section VII are one time only. There are no recurring requirements.

Uninstalled aileron hinges from the affected lots must be returned to McFarlane.

VII. ACCOMPLISHMENT INSTRUCTIONS

A. Disassembly

1. The hinge halves must be separated for proper inspection.

2. Remove the three attachment screws that lock the hinge pins into place.

3. Remove the hinge pins. Be sure not to mix the aileron hinge pins as they are select fit for each hinge.

4. Carefully support the aileron for inspection.

5. Inspect the affected hinges per Section VII B.

B. Inspection

1. Ensure that you can view each end of each of the aileron hinge tabs. This may require removal of paint from around each tab area to ensure full visibility.

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Service Bulletin 10, Revision A

2. Clean the hinge tab with appropriate solvent or detergent to expose the ends and body of the tab. All end surfaces must be clean and clear for inspection.

3. Using 10X magnifier, carefully inspect the ends of each hinge tab of each hinge half (surface and wing hinge half), for internal cracks and/or delamination in the bulb around the pin bore. Cracks and delamination defects appear as small lines that can extend from the pin bore to the outside surface of the tab or lines traveling around the pin bore. Refer to Figure 4 for examples of known defects.

Figure 4 – Known Internal Cracking and Delamination Defects

4. Inspect the visible hinge flat surface with a 10X magnifier. Inspect the flat side of each hinge tab for external cracks that extend the length of the hinge tab. Refer to Figure 5 for examples of possible defects.

Figure 5 – Known External Cracking Defect

5. If any cracks or defects are detected in either hinge half, remove and replace the hinge assembly per the instructions of aircraft service manual.

C. Reassembly and Return to Service

1. Reinstall the ailerons in the opposite manner as they were removed.

2. Using the service manual complete all required checks to return the aircraft to service

3. Make appropriate aircraft maintenance record entry for compliance with this service bulletin

VIII. MATERIAL PRICE AND AVAILABILITY

Part number MC0523816-1 aileron hinges are available from McFarlane

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Service Bulletin 10, Revision A

IX. CREDIT INFORMATION

McFarlane will issue a credit of $50.00 per aileron inspected from the affected lots (see Section IV). In addition, McFarlane will issue a credit of $40.00 per aileron hinge replaced from the affected lots. Part Credit and a ground freight allowance will be provided upon return of any defective parts. To receive credit for compliance with this service bulletin the aircraft N-number, model, and serial number along with a copy of the aircraft maintenance record entry showing compliance with this service bulletin will need to be provided.

X. DISTRIBUTION

This service bulletin has been distributed to all customers for whom McFarlane has sales records indicating the purchase of affected parts. All McFarlane service bulletins may also be found at www.mcfarlaneaviation.com. Please forward this urgent information to the current owner or operator of the affected aircraft. For further information or questions call (800) 544-8594 or (785) 594-2741. All persons are free to copy this bulletin if it is copied in its entirety with no alterations or additions.