2017-17399. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-300, -400, and -500 series airplanes. This AD was prompted by a manufacturer's review that showed that the fuel tank access door at a certain wing buttock line did not have an engineered ground path with the mating wing structure. This AD requires replacing the fuel tank access door, doing a check of the electrical bond, doing related investigative and corrective actions if necessary, and revising the maintenance or inspection program by incorporating an airworthiness limitation (AWL). We are issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective September 29, 2017.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of September 29, 2017.

ADDRESSES:

For service information identified in this final rule, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone [phone]; Internet https://www.myboeingfleet.com. You may view this service information at the FAA, Transport Standards Branch, 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-2017-0128.

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-2017-0128; 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 final rule, the regulatory evaluation, any comments received, and other information. The address for the Docket Office (phone: [phone]) is Docket Management Facility, U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

Serj Harutunian, Aerospace Engineer, Propulsion Section, FAA, Los Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: [phone]; fax: [phone]; email: [e-mail].

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all The Boeing Company Model 737-300, -400, and -500 series airplanes. The NPRM published in the Federal Register on March 9, 2017 (82 FR 13079). The NPRM was prompted by a report that the fuel tank access door at wing buttock line 191.00 did not have an engineered ground path with the mating wing structure. The NPRM proposed to require replacing the fuel tank access door, doing a check of the electrical bond, doing related investigative and corrective actions if necessary, and revising the maintenance or inspection program by incorporating an AWL. We are issuing this AD to prevent an ungrounded path that could result in an increased risk of ignition and subsequent fuel tank explosion in the event of a lightning strike.

Comments

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the NPRM and the FAA's response to each comment.

Support for the NPRM

The Air Line Pilots Association, International, stated that it supports the NPRM.

Request To Revise the Proposed AD To State the Compliance Time and Remove an Exception

Boeing requested that we revise paragraph (g) of the proposed AD to state the specific compliance time “within 36 months after the effective date of this AD,” rather than referring to the service information for compliance times. Boeing suggested that providing the compliance time in the body of the proposed AD would minimize confusion and misunderstanding.

Boeing also requested that we remove paragraph (i)(1) of the proposed AD, which specifies an exception to the compliance time stated in the service information. Boeing further noted that we would also need to renumber paragraph (i)(2) of the proposed AD and update references to the affected paragraphs of the proposed AD. Boeing pointed out that if we stated the specific compliance time as requested, the exception language in paragraph (i)(1) of the proposed AD is no longer necessary.

We agree with the requested changes for the reasons provided by the commenter. We have revised this AD accordingly.

Request To Correct the Certification Maintenance Requirements (CMR) Document Title

Boeing requested that we correct the title of the CMR document from “Boeing 737-12345 . . .” to “Boeing 737-100/200/200C/300/400/500 . . . .”

We agree with this request and have corrected the document title in this final rule.

Effects of Winglets on Accomplishment of the Proposed Actions

Aviation Partners Boeing stated that the installation of winglets per Supplemental Type Certificate (STC) ST01219SE does not affect the accomplishment of the manufacturer's service instructions.

We agree with the commenter that STC ST01219SE does not affect the accomplishment of the manufacturer's service instructions. Therefore the installation of STC ST01219SE does not affect the ability to accomplish the actions required by this AD. We have not changed this AD in this regard.

Conclusion

We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this final rule with the changes described previously and minor editorial changes. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and
• Do not add any additional burden upon the public than was already proposed in the NPRM.

We also determined that these changes will not increase the economic burden on any operator or increase the scope of this final rule.

Related Service Information Under 1 CFR Part 51

We reviewed the following service information.

• Boeing Service Bulletin 737-57-1320, dated October 7, 2016, which describes procedures for replacing the fuel tank access door with a new installation that has two engineered ground paths between the new door assembly and the mating wing structure, doing a check of the electrical bond, and related investigative and corrective actions.
• Boeing 737-100/200/200C/300/400/500 Airworthiness Limitations (AWLs) and Certification Maintenance Requirements (CMRs) D6-38278-CMR, dated May 2016. The AWL required by this AD is AWL 28-AWL-30 “Upper Wing Fuel Tank Access Panel—Lightning Protection Electrical Design Features,” which describes features to verify during installation of the upper fuel tank access panel.

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.

Costs of Compliance

We estimate that this AD affects 381 airplanes of U.S. registry. We estimate the following costs to comply with this AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Install new door assembly and check electrical bond	12 work-hours × $85 per hour = $1,020	$2,237	$3,257	$1,240,917
Revise maintenance or inspection program	1 work-hour × $85 per hour = $85	0	85	32,385

We have received no definitive data that would enable us to provide cost estimates for the on-condition actions specified in this AD.

According to the manufacturer, some of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected individuals. We do not control warranty coverage for affected individuals. As a result, we have included all costs in our cost estimate.

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.

This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes to the Director of the System Oversight Division.

Regulatory Findings

This AD will not have federalism implications under Executive Order 13132. This AD will 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 that this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Is not a “significant rule” under 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

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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):

2017-17-09 The Boeing Company: Amendment 39-18999; Docket No. FAA-2017-0128; Product Identifier 2016-NM-194-AD.

(a) Effective Date

This AD is effective September 29, 2017.

(b) Affected ADs

None.

(c) Applicability

This AD applies to all The Boeing Company Model 737-300, -400, and -500 series airplanes, certificated in any category.

(d) Subject

Air Transport Association (ATA) of America Code 57, Wings.

(e) Unsafe Condition

This AD was prompted by a manufacturer's review that showed that the fuel tank access door at wing buttock line 191.00 did not have an engineered ground path with the mating wing structure. We are issuing this AD to prevent an ungrounded path that could result in an increased risk of ignition and subsequent fuel tank explosion in the event of a lightning strike.

(f) Compliance

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

(g) New Door Assembly, Electrical Bond Check, and Related Corrective Actions

Within 36 months after the effective date of this AD: Install a new door assembly, do a check of the electrical bond, and do all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-57-1320, dated October 7, 2016, except as required by paragraph (i) of this AD. Do all applicable related investigative and corrective actions before further flight.

(h) Revise the Maintenance or Inspection Program

Prior to or concurrently with accomplishment of the actions required by paragraph (g) of this AD, or within 30 days after the effective date of this AD, whichever occurs later: Revise the maintenance or inspection program, as applicable, to incorporate Airworthiness Limitation 28-AWL-30, “Upper Wing Fuel Tank Access Panel—Lightning Protection Electrical Design Features,” as specified in Boeing 737-100/200/200C/300/400/500 Airworthiness Limitations (AWLs) and Certification Maintenance Requirements (CMRs) D6-38278-CMR, dated May 2016.

(i) Service Information Exception

Where Boeing Service Bulletin 737-57-1320, dated October 7, 2016, specifies to contact Boeing for repair instructions, and specifies that action as Required for Compliance (RC), this AD requires repair using a method approved in accordance with the procedures specified in paragraph (j) of this AD.

(j) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Los Angeles ACO Branch, 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 certification office, send it to the attention of the person identified in paragraph (k) 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, modification, or alteration required by this AD if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Los Angeles ACO Branch, to make those findings. To be approved, the repair method, modification deviation, or alteration deviation must meet the certification basis of the airplane, and the approval must specifically refer to this AD.

(4) Except as required by paragraph (i) of this AD: For service information that contains steps that are labeled as Required for Compliance (RC), the provisions of paragraphs (j)(4)(i) and (j)(4)(ii) of this AD 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. If a step or substep is labeled “RC Exempt,” then the RC requirement is removed from that step or substep. 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.

(k) Related Information

For more information about this AD, contact Serj Harutunian, Aerospace Engineer, Propulsion Section, FAA, Los Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: [phone]; fax: [phone]; email: [e-mail].

(l) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise.

(i) Boeing Service Bulletin 737-57-1320, dated October 7, 2016.

(ii) Boeing 737-100/200/200C/300/400/500 Airworthiness Limitations (AWLs) and Certification Maintenance Requirements (CMRs) D6-38278-CMR, dated May 2016.

(3) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone [phone]; Internet https://www.myboeingfleet.com.

(4) You may view this service information at the FAA, Transport Standards Branch, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425-227-1221.

(5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Issued in Renton, Washington, on August 9, 2017.

Dionne Palermo,

Acting Director, System Oversight Division, Aircraft Certification Service.