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52948, September 2, 2015, at the modified area only.

(2) Accomplishing the actions specified in paragraphs (i)(2)(i) and (i)(2)(ii) of this AD terminates the inspections required by paragraph (g) of AD 2014–20–10, Amendment 39–17983 (79 FR 60331, October 7, 2014), at the modified area only, provided the actions are accomplished concurrently, or the actions specified in paragraph (i)(2)(ii) of this AD are done after accomplishing the actions specified in paragraph (i)(2)(i) of this
AD.

(i) The actions specified in paragraphs (g)(1) through (g)(4) of this AD on the left and right struts are done in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777–71– 0055, Revision 1, dated April 15, 2015; and the revision specified in paragraph (g)(5) of this AD is done.

(ii) A one-time general visual inspection for hydraulic fluid contamination (including contamination caused by hydraulic fluid in its liquid, vapor, and/or solid (coked) form) of the interior of the strut forward dry bay, and all applicable related investigative and corrective actions (including checking drain lines for blockage due to hydraulic fluid coking, and cleaning or replacing drain lines to allow drainage) are done in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777–54–0028, Revision 1, dated December 10, 2013, except where Boeing Special Attention Service Bulletin 777–54–0028, Revision 1, dated December 10, 2013, specifies to contact Boeing for repair, the repair must be done using a method approved in accordance with the procedures specified in paragraph (k) of this AD.
(j) Credit for Previous Actions

This paragraph provides credit for actions required by paragraph (g) of this AD, if those actions were performed before the effective date of this AD using Boeing Special Attention Service Bulletin 777–71–0055, dated June 12, 2014, which is not incorporated by reference in this AD.
(k) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in paragraph (l)(1) of this AD. Information may be emailed to: 9-ANM-Seattle-ACO-AMOCRequests@faa.gov.

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/ certificate holding district office.

(3) For service information that contains steps that are labeled as Required for Compliance (RC), the provisions of paragraphs (k)(3)(i) and (k)(3)(ii) apply.

(i) The steps labeled as RC, including substeps under an RC step and any figures identified in an RC step, must be done to comply with the AD. An AMOC is required for any deviations to RC steps, including substeps and identified figures.

(ii) Steps not labeled as RC may be deviated from using accepted methods in accordance with the operator’s maintenance or inspection program without obtaining approval of an AMOC, provided the RC steps, including substeps and identified figures, can still be done as specified, and the airplane can be put back in an airworthy condition.

(l) Related Information

(1) For more information about this AD, contact Kevin Nguyen, Aerospace Engineer, Propulsion Branch, ANM–140S, FAA, Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue SW., Renton, WA 98057–3356; phone: 425–917–6501; fax: 425–917–6590; email: kevin.nguyen@faa.gov.

(2) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H–65, Seattle, WA 98124–2207; telephone 206– 544–5000, extension 1; fax 206–766–5680;
Internet https://www.myboeingfleet.com. You may view this referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425–227–1221.

Issued in Renton, Washington, on December 21, 2015. Michael Kaszycki, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

[FR Doc. 2015–32852 Filed 12–30–15; 8:45 am]

**BILLING CODE 4910–13–P**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2015–8132; Directorate Identifier 2015–NM–127–AD]** 

**RIN 2120–AA64**

**Airworthiness Directives; Airbus Airplanes** 

**AGENCY :**  Federal Aviation Administration (FAA), DOT.

**ACTION :**  Notice of proposed rulemaking (NPRM).

**SUMMARY :**  We propose to adopt a new airworthiness directive (AD) for certain Airbus Model A318, A319, A320, and A321 series airplanes. This proposed AD was prompted by a report of cracks found during maintenance inspections on certain lugs of the 10VU rack side fittings in the cockpit. This proposed AD would require repetitive inspections for cracking of the lugs on the 10VU rack side fittings, and repair of any cracking. We are proposing this AD to prevent loss of flight-critical information displayed to the flightcrew during a critical phase of flight, such as an approach or takeoff, which could result in loss of airplane control at an altitude insufficient for recovery.

**DATES :**  We must receive comments on this proposed AD by February 16, 2016.

**ADDRESSES :**  You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.

• Fax: 202–493–2251.

• Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590.

• Hand Delivery: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Airbus, Airworthiness Office—EIAS, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France; telephone +33 5 61 93 36 96; fax +33 5 61 93 44 51; email account.airworth-eas@airbus.com;
Internet http://www.airbus.com.

You may view this referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425–227–1221.
Examining the AD Docket

You may examine the AD docket on the Internet at http:// www.regulations.gov by searching for and locating Docket No. FAA–2015– 8132; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone 800–647–5527) is in the **ADDRESSES** section. Comments will be available in the AD docket shortly after receipt.

**FOR FURTHER INFORMATION CONTACT :**  Sanjay Ralhan, Aerospace Engineer, International Branch, ANM–116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, WA 98057–3356; telephone 425–227–1405; fax 425–227–1149.

**SUPPLEMENTARY INFORMATION :** 


### 81793 Federal Register / Vol. 80, No. 251 / Thursday, December 31, 2015 / Proposed Rules

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the

**ADDRESSES** section. Include ‘‘Docket No. FAA–2015–8132; Directorate Identifier 2015–NM–127–AD’’ at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD based on those comments.

We will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA Airworthiness Directive 2015–0170, dated August 18, 2015 (referred to after this as the Mandatory Continuing Airworthiness Information, or ‘‘the MCAI’’), to correct an unsafe condition for certain Airbus Model A318, A319, A320, and A321 series airplanes. The MCAI states:

During an unscheduled maintenance operation on an A330 aeroplane, the 10VU
rack was removed for access and cracks were discovered on 10VU rack side fittings on lugs 1, 3, and 4. As a similar design is installed on A320 family aeroplanes, a sampling review was done to determine the possible fleet impact. The result showed that several aeroplanes had cracked or broken 10VU rack side fittings.

This condition, if not detected and corrected, could lead to a high vibration level on the primary flight- and navigation displays during critical flight phases (takeoff and landing), possibly creating reading difficulties for the crew.

Prompted by these findings, Airbus developed mod 35869 to reinforce the affected rack fitting lugs. For in-service aeroplanes, Airbus published Service Bulletin (SB) A320–92–1087 to provide inspection and repair instructions.

For the reasons described above, this [EASA] AD requires repetitive detailed inspections (DET) of the affected 10VU rack fitting lugs and, depending on findings, accomplishment of a repair.

You may examine the MCAI in the AD docket on the Internet at http:// www.regulations.gov by searching for and locating Docket No. FAA–2015–

8132. Related Service Information Under 1
CFR Part 51

Airbus has issued Service Bulletin A320–92–1087, Revision 02, dated November 25, 2014. The service information describes procedures for repetitive inspections for cracking of the lugs on the 10VU rack side fittings, and repair of any cracking. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the **ADDRESSES** section of this AD.
FAA’s Determination and Requirements of This Proposed AD

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are proposing this AD because we evaluated all pertinent information and determined an unsafe condition exists and is likely to exist or develop on other products of these same type designs.
Explanation of ‘‘RC’’ Procedures and Tests in Service Information

The FAA worked in conjunction with industry, under the Airworthiness Directive Implementation Aviation Rulemaking Committee (ARC), to enhance the AD system. One enhancement was a new process for annotating which procedures and tests in the service information are required for compliance with an AD. Differentiating these procedures and tests from other tasks in the service information is expected to improve an owner’s/operator’s understanding of crucial AD requirements and help provide consistent judgment in AD compliance. The procedures and tests identified as RC (required for compliance) in any service information have a direct effect on detecting, preventing, resolving, or eliminating an identified unsafe condition.

As specified in a Note under the Accomplishment Instructions of the specified service information, procedures and tests that are identified as RC in any service information must be done to comply with the proposed AD. However, procedures and tests that are not identified as RC are recommended. Those procedures and tests that are not identified as RC may be deviated from using accepted methods in accordance with the operator’s maintenance or inspection program without obtaining approval of an alternative method of compliance (AMOC), provided the procedures and tests identified as RC can be done and the airplane can be put back in an airworthy condition. Any substitutions or changes to procedures or tests identified as RC will require approval of
an AMOC.
Costs of Compliance

We estimate that this proposed AD affects 959 airplanes of U.S. registry.

We also estimate that it would take about 2 work-hours per product to comply with the basic requirements of this proposed AD, and 1 work-hour per product to report inspection findings.The average labor rate is $85 per workhour. Based on these figures, we estimate the cost of this proposed AD on U.S. operators to be $244,545, or $255 per product.

In addition, we estimate that any necessary repair would take about 84 work-hours, for a cost of $7,140 per product. We have received no definitive data that would enable us to provide part cost estimates for the on-condition actions specified in this proposed AD. We have no way of determining the number of aircraft that might need these
actions.
Paperwork Reduction Act

A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB control number. The control number for the collection of information required by this AD is 2120–0056. The paperwork cost associated with this AD has been detailed in the Costs of Compliance section of this document and includes time for reviewing instructions, as well as completing and reviewing the collection of information. Therefore, all reporting associated with this AD is mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at 800 Independence Ave. SW., Washington, DC 20591, ATTN: Information Collection Clearance Officer, AES–200.
Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA’s authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. ‘‘Subtitle VII: Aviation Programs,’’ describes in more


### 81794 Federal Register / Vol. 80, No. 251 / Thursday, December 31, 2015 / Proposed Rules

detail the scope of the Agency’s authority.

We are issuing this rulemaking under the authority described in ‘‘Subtitle VII, Part A, Subpart III, Section 44701: General requirements.’’ Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking
action.
Regulatory Findings

We determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a substantial direct effect on the States, on the relationship between the national Government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify this proposed regulation:

1. Is not a ‘‘significant regulatory action’’ under Executive Order 12866;

2. Is not a ‘‘significant rule’’ under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);

3. Will not affect intrastate aviation in Alaska; and

4. Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.
List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

**PART 39—AIRWORTHINESS DIRECTIVES** 

■ 1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

**§ 39.13 [Amended]**

■ 2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):

Airbus: Docket No. FAA–2015–8132; Directorate Identifier 2015–NM–127–AD. (a) Comments Due Date We must receive comments by February
16, 2016.

(b) Affected ADs

None.
(c) Applicability

This AD applies to the Airbus airplanes identified in paragraphs (c)(1) through (c)(4) of this AD, certificated in any category; except airplanes on which Airbus Modification 35869 has been embodied in production.

(1) Airbus Model A318–111, –112, –121, and –122 airplanes.

(2) Airbus Model A319–111, –112, –113, –114, –115, –131, –132, and –133 airplanes.

(3) Airbus Model A320–211, –212, –214, –231, –232, and –233 airplanes.

(4) Airbus Model A321–111, –112, –131, –211, –212, –213, –231, and –232 airplanes.
(d) Subject

Air Transport Association (ATA) of America Code 25, Equipment/Furnishings.

(e) Reason

This AD was prompted by a report of cracks found during maintenance inspections on certain lugs of the 10VU rack side fittings in the cockpit. We are issuing this AD to prevent loss of flight-critical information displayed to the flightcrew during a critical phase of flight, such as an approach or takeoff, which could result in loss of airplane control at an altitude insufficient for

recovery. (f) Compliance

Comply with this AD within the compliance times specified, unless already done.
(g) Repetitive Inspections and Repair

At the later of the times specified in paragraphs (g)(1) and (g)(2) of this AD: Do a detailed inspection for cracking of the lugs on the 10VU rack side fittings in the cockpit, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320– 92–1087, Revision 02, dated November 25, 2014. If any crack is found, before further flight, repair in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320–92–1087, Revision 02, dated November 25, 2014. Repeat the inspection thereafter at intervals not to exceed 20,000 flight cycles or 40,000 flight hours, whichever occurs first. Repair of the 10VU rack lugs does not terminate the repetitive inspections required by this paragraph.

(1) Before the accumulation of 30,000 total flight cycles or 60,000 total flight hours, whichever occurs first since the airplane’s first flight.

(2) Within 24 months after the effective date of this AD.
(h) Reporting Requirement

Submit a report of any findings (positive and negative) of any inspection required by paragraph (g) of this AD to Airbus at the address specified in paragraph (j)(2) of this AD, at the applicable time specified in paragraph (h)(1) or (h)(2) of this AD. (1) If the inspection was done on or after the effective date of this AD: Submit the report within 90 days after the inspection.

(2) If the inspection was done before the effective date of this AD: Submit the report within 90 days after the effective date of this
AD.

(i) Other FAA AD Provisions

The following provisions also apply to this
AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, International Branch, ANM–116, Transport Airplane Directorate, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the International Branch, send it to ATTN: Sanjay Ralhan, Aerospace Engineer, International Branch, ANM–116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, WA 98057–3356; telephone 425–227–1405; fax 425–227–1149. Information may be emailed to: 9-ANM-116- AMOC-REQUESTS@faa.gov. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office. The AMOC approval letter must specifically reference this AD.

(2) Contacting the Manufacturer: For any requirement in this AD to obtain corrective actions from a manufacturer, the action must be accomplished using a method approved by the Manager, International Branch, ANM– 116, Transport Airplane Directorate, FAA; or the European Aviation Safety Agency (EASA); or Airbus’s EASA Design Organization Approval (DOA). If approved by the DOA, the approval must include the DOA-authorized signature.

(3) Reporting Requirements: A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB Control Number. The OMB Control Number for this information collection is 2120–0056. Public reporting for this collection of information is estimated to be approximately 5 minutes per response, including the time for reviewing instructions, completing and reviewing the collection of information. All responses to this collection of information are mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at: 800 Independence Ave. SW., Washington, DC 20591, Attn: Information Collection Clearance Officer,
AES–200.

(4) Required for Compliance (RC): If any service information contains procedures or tests that are identified as RC, those procedures and tests must be done to comply with this AD; any procedures or tests that are not identified as RC are recommended. Those procedures and tests that are not identified


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as RC may be deviated from using accepted methods in accordance with the operator’s maintenance or inspection program without obtaining approval of an AMOC, provided the procedures and tests identified as RC can be done and the airplane can be put back in an airworthy condition. Any substitutions or changes to procedures or tests identified as RC require approval of an AMOC.
(j) Related Information

(1) Refer to Mandatory Continuing Airworthiness Information (MCAI) European Aviation Safety Agency (EASA) Airworthiness Directive 2015–0170, dated August 18, 2015, for related information. This MCAI may be found in the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No.
FAA–2015–8132.

(2) For service information identified in this AD, contact Airbus, Airworthiness Office—EIAS, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France; telephone +33 5 61 93 36 96; fax +33 5 61 93 44 51; email account.airwortheas@airbus.com; Internet http:// www.airbus.com . You may view this service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425–227–1221.

Issued in Renton, Washington, on December 18, 2015. Jeffrey E. Duven, Manager, Transport Airplane Directorate, Aircraft Certification Service.

[FR Doc. 2015–32885 Filed 12–30–15; 8:45 am]

**BILLING CODE 4910–13–P**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2015–8133; Directorate Identifier 2015–NM–101–AD]** 

**RIN 2120–AA64**

**Airworthiness Directives; The Boeing Company Airplanes** 

**AGENCY :**  Federal Aviation Administration (FAA), DOT.

**ACTION :**  Notice of proposed rulemaking (NPRM).

**SUMMARY :**  We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 737–600, –700, –700C, –800, –900, and –900ER series airplanes. This proposed AD was prompted by reports of heavy corrosion and chrome damage on the forward and aft trunnion pin assemblies of the right and left main landing gears (MLGs). This proposed AD would require repetitive lubrication of the forward and aft trunnion pin assemblies of the right and left MLGs; repetitive inspections of these assemblies for corrosion and chrome damage, and related investigative and corrective actions if necessary; and the installation of new or modified trunnion pin assembly components, which would terminate the repetitive lubrication and repetitive inspections. We are proposing this AD to detect and correct heavy corrosion and chrome damage on the forward and aft trunnion pin assemblies of the right and left MLGs, which could result in cracking of these assemblies and collapse of the MLGs.

**DATES :**  We must receive comments on this proposed AD by February 16, 2016.

**ADDRESSES :**  You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.

• Fax: 202–493–2251.

• Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590.

• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H–65, Seattle, WA 98124–2207; telephone 206–544–5000, extension 1; fax 206–766–5680; Internet https:// www.myboeingfleet.com . You may view this referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425–227–1221. It is also available on the Internet at http:// www.regulations.gov by searching for and locating Docket No. FAA–2015–

8133. Examining the AD Docket

You may examine the AD docket on the Internet at http:// www.regulations.gov by searching for and locating Docket No. FAA–2015– 8133; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (phone: 800–647–5527) is in the

**ADDRESSES** section. Comments will be available in the AD docket shortly after receipt. **FOR FURTHER INFORMATION CONTACT :**  Alan Pohl, Aerospace Engineer, Airframe Branch, ANM–120S, FAA Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057–3356; phone: 425–917–6450; fax: 425–917–6590; email: alan.pohl@ faa.gov

. **SUPPLEMENTARY INFORMATION :** 

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the **ADDRESSES** section. Include ‘‘Docket No. FAA– 2015–8133; Directorate Identifier 2015– NM–101–AD at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those

comments.

We will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

We received reports of heavy corrosion and chrome damage of the forward and aft trunnion pin assemblies of the right and left main MLGs on Boeing Model 737–600, –700, –700C, –800, –900, and –900ER series airplanes. Investigation revealed that the lubrication between the forward and aft trunnion pin assemblies and the outer cylinder assembly bushings and the lubrication of the aft trunnion bearing ball was not sufficient to prevent wear and corrosion. It was also determined that the clearances between the forward and aft trunnion pin cross bolt bushings and the cross bolts could affect the rate of wear and corrosion of the MLG trunnion pin assemblies. Corrosion and chrome damage of the forward and aft trunnion pin assemblies of the right and left main MLGs, if not corrected, could result in cracking of these assemblies and collapse of the MLGs.

Related Service Information Under 1
CFR Part 51

We reviewed Boeing Special Attention Service Bulletin 737–32– 1448, Revision 1, dated May 29, 2015. The service information describes procedures for lubricating the forward and aft trunnion pin assemblies on the left and right MLGs, inspecting the forward and aft trunnion pin assemblies