2011-33544. 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 777-200 and -300 series airplanes. This proposed AD was prompted by reports of cracked retract actuator fuse pins that can fail earlier than the previously determined safe life limit of the pins. A fractured retract actuator fuse pin can cause the main landing gear (MLG) to extend without restriction and attempt to lock into position under high dynamic loads. This proposed AD would require an inspection for the part number of the fuse pin, and replacement of the pin if necessary. We are proposing this AD to prevent structural damage to the side and drag brace lock assemblies, which could result in landing gear collapse during touchdown, rollout, or taxi.

DATES:

We must receive comments on this proposed AD by February 13, 2012.

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: [phone].
• 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, Washington 98124-2207; telephone [phone], extension 1; fax [phone]; email [e-mail]; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call [phone].

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov;​; 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: [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

James Sutherland, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: [phone]; fax: [phone]; email: [e-mail].

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-2011-1412; Directorate Identifier 2011-NM-158-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 have received reports of cracked retract actuator fuse pins that can fail earlier than previously determined safe life limit of the pins. A fractured retract actuator fuse pin can cause the main landing gear (MLG) to extend without restriction and attempt to lock into position under high dynamic loads. Unrestricted MLG extension could cause structural damage to the side and drag brace lock assemblies. This condition, if not corrected, could result in structural damage to the side and drag brace lock assemblies, which could result in landing gear collapse during touchdown, rollout, or taxi.

Relevant Service Information

We reviewed Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011. The service information describes procedures for inspecting the retract actuator fuse pin to identify the part number of the pin and, if an affected pin is found, replacing it with a new part number pin.

FAA's Determination

We are proposing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of these same type designs.

Proposed AD Requirements

This proposed AD would require accomplishing the actions specified in the service information described previously.

Costs of Compliance

We estimate that this proposed AD affects 35 airplanes of U.S. registry.

We estimate the following costs to comply with this proposed AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Inspection	4 work-hours × $85 per hour = $340	$0	$340	$11,900

We estimate the following costs to do any necessary pin replacements that would be required based on the results of the proposed inspection. We have no way of determining the number of aircraft that might need these replacements:

On-Condition Costs

Action	Labor cost	Parts cost	Cost per product
Pin replacement	1 work-hour × $85 per hour = $85 per pin	$769 per pin	$854 per pin.

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 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):

The Boeing Company: Docket No. FAA-2011-1412; Directorate Identifier 2011-NM-158-AD.

(a) Comments Due Date

We must receive comments by February 13, 2012.

(b) Affected ADs

None.

(c) Applicability

This AD applies to The Boeing Company Model 777-200 and -300 series airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011.

(d) Subject

Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 32, Main landing gear.

(e) Unsafe Condition

This AD was prompted by reports of cracked retract actuator fuse pins that can fail earlier than the previously determined safe life limit of the pins. A fractured retract actuator fuse pin can cause the main landing gear (MLG) to extend without restriction and attempt to lock into position under high dynamic loads. We are issuing this AD to prevent structural damage to the side and drag brace lock assemblies, which could result in landing gear collapse during touchdown, rollout, or taxi.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Inspection of Retract Actuator Fuse Pin

Within 6 months after the effective date of this AD: Inspect the part number of the fuse pins of the left and right MLG retract actuators, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011. A review of airplane maintenance records is acceptable in lieu of this inspection if the part number of the installed actuator fuse pin can be conclusively determined from that review.

(1) If any retract actuator fuse pin having part number 112W1769-3 is found installed, no further action is required by this paragraph for that fuse pin.

(2) If any retract actuator fuse pin having part number 112W1769-1 is found installed and the pin has accumulated more than 10,000 total flight cycles as of the effective date of this AD: Within 6 months after the effective date of this AD, replace the fuse pin with a new part number 112W1769-3 fuse pin, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011.

(3) If any retract actuator fuse pin having part number 112W1769-1 is found installed and the pin has accumulated 8,000 or more, but fewer than or equal to 10,000 total flight cycles, as of the effective date of this AD: Before the accumulation of 10,000 total flight cycles on the pin, or within 12 months after the effective date of this AD, whichever occurs later, replace the fuse pin with a new part number 112W1769-3 fuse pin, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011.

(4) If any retract actuator fuse pin having part number 112W1769-1 is found installed and the pin has accumulated fewer than 8,000 total flight cycles as of the effective date of this AD: Before the accumulation of 8,000 total flight cycles on the pin, or within 24 months after the effective date of this AD, whichever occurs later, replace the fuse pin with a new part number 112W1769-3 fuse pin, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011.

(h) Parts Installation

As of the effective date of this AD, no person may install a retract actuator fuse pin having P/N 112W1769-1 on any airplane.

(i) Credit for Actions Accomplished in Accordance With Previous Service Information

Actions done before the effective date of this AD in accordance with Boeing Special Attention Service Bulletin 777-32-0083, dated February 5, 2009, are acceptable for compliance with the corresponding requirements of this AD.

(j) 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 the Related Information section of this AD. Information may be emailed to: [e-mail].

(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) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD if it is approved by Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.

(k) Related Information

(1) For more information about this AD, contact James Sutherland, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: [phone]; fax: [phone]; email: [e-mail].

(2) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P. O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone [phone], extension 1; fax [phone]; email [e-mail]; Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call [phone].

Issued in Renton, Washington, on December 23, 2011.

John P. Piccola,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.