Document ID: FAA-2020-0341-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: The Boeing Company Airplanes
Posted Date: 2020-05-06T04:00Z

[Federal Register Volume 85, Number 88 (Wednesday, May 6, 2020)]
[Proposed Rules]
[Pages 26888-26891]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-09395]

 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
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 

  Federal Register / Vol. 85, No. 88 / Wednesday, May 6, 2020 / 
Proposed Rules  

[[Page 26888]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0341; Product Identifier 2020-NM-017-AD]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes 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 
significant changes made to the airworthiness limitations (AWLs) 
related to fuel tank ignition prevention and the nitrogen generation 
system. This proposed AD would require revising the existing 
maintenance or inspection program, as applicable, to incorporate the 
latest revision of the AWLs. The FAA is proposing this AD to address 
the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by June 22, 
2020.

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 https://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 NPRM, contact Boeing 
Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 
2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; 
telephone 562-797-1717; internet https://www.myboeingfleet.com. You may 
view this service information at the FAA, Airworthiness Products 
Section, Operational Safety Branch, 2200 South 216th St., Des Moines, 
WA. For information on the availability of this material at the FAA, 
call 206-231-3195.

Examining the AD Docket

    You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-
0341; or in person at Docket Operations between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays. The AD docket contains 
this NPRM, any comments received, and other information. The street 
address for Docket Operations is listed above. Comments will be 
available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Christopher Baker, Aerospace Engineer, 
Propulsion Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des 
Moines, WA 98198; phone and fax: 206-231-3556; email: 
Christopher.R.Baker@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    The FAA invites 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-2020-0341; 
Product Identifier 2020-NM-017-AD'' at the beginning of your comments. 
The FAA specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this NPRM. The FAA will 
consider all comments received by the closing date and may amend this 
NPRM because of those comments.
    The FAA will post all comments received, without change, to https://www.regulations.gov, including any personal information you provide. 
The FAA will also post a report summarizing each substantive verbal 
contact received about this NPRM.

Discussion

    The FAA has examined the underlying safety issues involved in fuel 
tank explosions on several large transport airplanes, including the 
adequacy of existing regulations, the service history of airplanes 
subject to those regulations, and existing maintenance practices for 
fuel tank systems. As a result of those findings, the FAA issued a 
final rule titled ``Transport Airplane Fuel Tank System Design Review, 
Flammability Reduction and Maintenance and Inspection Requirements'' 
(66 FR 23086, May 7, 2001). In addition to new airworthiness standards 
for transport airplanes and new maintenance requirements that rule 
included Amendment 21-78, which established Special Federal Aviation 
Regulation No. 88 (``SFAR 88'') at 14 CFR part 21. Subsequently, SFAR 
88 was amended by Amendment 21-82 (67 FR 57490, September 10, 2002; 
corrected at 67 FR 70809, November 26, 2002), Amendment 21-83 (67 FR 
72830, December 9, 2002; corrected at 68 FR 37735, June 25, 2003, to 
change ``21-82'' to ``21-83''), and Amendment 21-101 (83 FR 9162, March 
5, 2018).
    Among other actions, SFAR 88 requires certain type design (i.e., 
type certificate (TC) and supplemental type certificate (STC)) holders 
to substantiate that their fuel tank systems can prevent ignition 
sources in the fuel tanks. This requirement applies to type design 
holders for large turbine-powered transport airplanes and for 
subsequent modifications to those airplanes. It requires them to 
perform design reviews and to develop design changes and maintenance 
procedures if their designs do not meet the new fuel tank safety 
standards. As explained in the preamble to the final rule published on 
May 7, 2001, the FAA intended to adopt airworthiness directives to 
mandate any changes found necessary to address unsafe conditions 
identified as a result of these reviews.
    In evaluating these design reviews, the FAA has established four 
criteria intended to define the unsafe conditions associated with fuel 
tank systems that require corrective actions. The percentage of 
operating time during which fuel tanks are exposed to flammable 
conditions is one of these criteria. The other three criteria address 
the failure types under evaluation: single failures, single failures in

[[Page 26889]]

combination with another latent condition(s), and in-service failure 
experience. For all four criteria, the evaluations included 
consideration of previous actions taken that may mitigate the need for 
further action.
    The FAA has determined that the actions identified in this proposed 
AD are necessary to reduce the potential of ignition sources inside 
fuel tanks, which, in combination with flammable fuel vapors, could 
result in fuel tank explosions and consequent loss of the airplane.
    The FAA issued AD 2008-10-10 R1, Amendment 39-16164 (75 FR 1529, 
January 12, 2010) (``AD 2008-10-10 R1'') and AD 2018-20-24, Amendment 
39-19458 (83 FR 51815, October 15, 2018) (``AD 2018-20-24''), which 
apply to certain The Boeing Company Model 737-600, -700, -700C, -800, 
and -900 series airplanes. AD 2008-10-10 R1 and AD 2018-20-24 require 
incorporation of fuel system AWLs and also require an initial 
inspection to phase in certain repetitive inspections, and repair if 
necessary. The fuel system AWLs were developed to satisfy SFAR 88 
requirements and included in the Airworthiness Limitations Section 
(ALS) of the manufacturer's Instructions for Continued Airworthiness. 
Since AD 2008-10-10 R1 and AD 2018-20-24 were issued, the ALS has been 
significantly revised by the manufacturer to correct technical and 
editorial errors and also to add new requirements. Those changes affect 
the fuel system and nitrogen generation system AWLs.
    The FAA proposes to adopt this new AD to require revising the 
maintenance or inspection program, as applicable, to incorporate the 
latest revision of the AWLs. The FAA is proposing this AD to prevent 
the potential for ignition sources inside the fuel tanks and also to 
prevent increasing the flammability exposure of the center fuel tank 
caused by latent failures, alterations, repairs, or maintenance 
actions, which could result in a fuel tank explosion and consequent 
loss of an airplane.
    The FAA has determined that accomplishing the revision required by 
paragraph (g) of this proposed AD would terminate the following 
requirements for that airplane:
     All requirements of AD 2008-10-10 R1.
     The revision required by paragraphs (h) and (h)(1) of AD 
2008-06-03, Amendment 39-15415 (73 FR 13081, March 12, 2008).
     The revision required by paragraph (g) of AD 2008-17-15, 
Amendment 39-15653 (73 FR 50714, August 28, 2008).
     The revision required by paragraph (k) of AD 2011-18-03, 
Amendment 39-16785 (76 FR 53317, August 26, 2011).
     All requirements of AD 2013-15-17, Amendment 39-17533 (78 
FR 52838, August 27, 2013).
     All requirements of AD 2018-20-24.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing 737-600/700/700C/800/900/900ER Special 
Compliance Items/Airworthiness Limitations, D626A001-9-04, dated April 
2019. This service information describes AWLs that include 
airworthiness limitation instructions (ALIs) and critical design 
configuration control limitations (CDCCLs) tasks related to fuel tank 
ignition prevention and the nitrogen generation system. 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.

FAA's Determination

    The FAA is proposing this AD because the agency evaluated all the 
relevant information and determined the unsafe condition described 
previously is likely to exist or develop in other products of the same 
type design.

Proposed AD Requirements

    This proposed AD would require revising the existing maintenance or 
inspection program, as applicable, to incorporate new or more 
restrictive airworthiness limitations.
    This proposed AD would require revisions to certain operator 
maintenance documents to include new actions (e.g., inspections) and 
CDCCLs. Compliance with these actions and CDCCLs is required by 14 CFR 
91.403(c). For airplanes that have been previously modified, altered, 
or repaired in the areas addressed by this proposed AD, the operator 
may not be able to accomplish the actions described in the revisions. 
In this situation, to comply with 14 CFR 91.403(c), the operator must 
request approval for an alternative method of compliance according to 
paragraph (k) of this proposed AD.

Differences Between This Proposed AD and the Service Information

    The ``description'' column of AWL No. 28-AWL-20 identifies certain 
operational tests. However, airplanes on which the actions specified in 
paragraph (g)(2)(ii) of AD 2011-20-07, Amendment 39-16818 (76 FR 60710, 
September 30, 2011), have been done are not required to do the 
operational test for left center tank fuel boost pump relay R54 and 
right center tank fuel boost pump relay R55.
    Paragraph (g) of this proposed AD would require operators to revise 
their existing maintenance or inspection program by incorporating, in 
part, AWL No. 28-AWL-05, ``Wire Separation Requirements for New Wiring 
Installed in Proximity to Wiring That Goes Into the Fuel Tanks'' in 
Boeing 737-600/700/700C/800/900/900ER Special Compliance Items/
Airworthiness Limitations, D626A001-9-04, dated April 2019. Paragraph 
(h) of this proposed AD would allow certain changes to be made to the 
requirements specified in AWL No. 28-AWL-05 as an option.

Clarification of the Service Information

    The ``applicability'' column of AWL No. 28-AWL-19 identifies 
affected airplanes. For airplanes on which the actions specified in 
paragraph (s) of AD 2011-18-03 have been done, incorporation of Boeing 
Service Bulletin 737-28A1206 is not required. Therefore, those 
airplanes are not affected by AWL No. 28-AWL-19 and are not required to 
do the functional test.
    The ``applicability'' column of AWL No. 28-AWL-23 identifies 
affected airplanes. For airplanes on which the actions specified in 
paragraph (s) of AD 2011-18-03 have been done, incorporation of Boeing 
Service Bulletin 737-28A1248 is not required. Therefore, those 
airplanes are not affected by AWL No. 28-AWL-23 and are not required to 
do the functional test.

Costs of Compliance

    The FAA estimates that this proposed AD affects 2,057 airplanes of 
U.S. registry. The FAA estimates the following costs to comply with 
this proposed AD:
    The FAA determined that revising the existing maintenance or 
inspection program takes an average of 90 work-hours per operator, 
although the agency recognizes that this number may vary from operator 
to operator. In the past, the FAA estimated that this action takes 1 
work-hour per airplane. Since operators incorporate maintenance or 
inspection program changes for their affected fleet(s), the FAA 
determined that a per-operator estimate is more accurate than a per-
airplane estimate. Therefore, the FAA estimates the average total cost 
per operator to be $7,650 (90 work-hours x $85 per work-hour).

[[Page 26890]]

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.
    The FAA is 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

    The FAA 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) Will not affect intrastate aviation in Alaska, and
    (3) 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

0
1. The authority citation for part 39 continues to read as follows:

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

Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

The Boeing Company: Docket No. FAA-2020-0341; Product Identifier 
2020-NM-017-AD.

(a) Comments Due Date

    The FAA must receive comments by June 22, 2020.

(b) Affected ADs

    This AD affects the ADs specified in paragraphs (b)(1) through 
(6) of this AD.
    (1) AD 2008-06-03, Amendment 39-15415 (73 FR 13081, March 12, 
2008) (``AD 2008-06-03'').
    (2) AD 2008-10-10 R1, Amendment 39-16164 (75 FR 1529, January 
12, 2010) (``AD 2008-10-10 R1'').
    (3) AD 2008-17-15, Amendment 39-15653 (73 FR 50714, August 28, 
2008) (``AD 2008-17-15'').
    (4) AD 2011-18-03, Amendment 39-16785 (76 FR 53317, August 26, 
2011) (``AD 2011-18-03'').
    (5) AD 2013-15-17, Amendment 39-17533 (78 FR 52838, August 27, 
2013) (``AD 2013-15-17'').
    (6) AD 2018-20-24, Amendment 39-19458 (83 FR 51815, October 15, 
2018) (``AD 2018-20-24'').

(c) Applicability

    This AD applies to The Boeing Company Model 737-600, -700, -
700C, -800, -900, and -900ER series airplanes, certificated in any 
category, with an original airworthiness certificate or original 
export certificate of airworthiness issued on or before December 18, 
2019.

(d) Subject

    Air Transport Association (ATA) of America Code 71, Powerplant.

(e) Unsafe Condition

    This AD was prompted by significant changes made to the 
airworthiness limitations (AWLs) related to fuel tank ignition 
prevention and the nitrogen generation system. The FAA is issuing 
this AD to address the development of an ignition source inside the 
fuel tanks and also to prevent increasing the flammability exposure 
of the center fuel tank, which could lead to fuel tank explosion and 
consequent loss of the airplane.

(f) Compliance

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

(g) Maintenance or Inspection Program Revision

    Within 60 days after the effective date of this AD, revise the 
existing maintenance or inspection program, as applicable, to 
incorporate the information specified in Section A, including 
Subsections A.1., A.2., and A.3, of Boeing 737-600/700/700C/800/900/
900ER Special Compliance Items/Airworthiness Limitations, D626A001-
9-04, dated April 2019; except as provided by paragraph (h) of this 
AD. The initial compliance times for the airworthiness limitation 
instruction (ALI) tasks are within the applicable compliance times 
specified in in paragraphs (g)(1) through (14) of this AD.
    (1) For AWL No. 28-AWL-01, ``External Wires Over Center Fuel 
Tank:'' Within 120 months after the date of issuance of the original 
airworthiness certificate or the original export certificate of 
airworthiness, or within 120 months after the most recent inspection 
was performed as specified in AWL No. 28-AWL-01, whichever is later.
    (2) For AWL No. 28-AWL-03, ``Fuel Quantity Indicating System 
(FQIS)-Out Tank Wiring Lightning Shield to Ground Termination:'' 
Within 120 months after the date of issuance of the original 
airworthiness certificate or the original export certificate of 
airworthiness, or within 120 months after the most recent inspection 
was performed as specified in AWL No. 28-AWL-03, whichever is later.
    (3) For AWL No. 28-AWL-19, ``Center Tank Fuel Boost Pump 
Automatic Shutoff System:'' Within 12 months after the date of 
issuance of the original airworthiness certificate or the original 
export certificate of airworthiness, within 12 months after 
accomplishment of the actions specified in Boeing Service Bulletin 
737-28A1206, or within 12 months after the most recent inspection 
was performed as specified in AWL No. 28-AWL-19, whichever is 
latest. This AWL does not apply to airplanes that have complied with 
paragraph (s) of AD 2011-18-03.
    (4) For AWL No. 28-AWL-20, ``Over-Current and Arcing Protection 
Electrical Design Features Operation-Boost Pump Ground Fault 
Interrupter (GFI):'' Within 12 months after the date of issuance of 
the original airworthiness certificate or the original export 
certificate of airworthiness, within 12 months after accomplishment 
of the actions specified in Boeing Service Bulletin 737-28A1201, or 
within 12 months after the most recent inspection was performed as 
specified in AWL No. 28-AWL-20, whichever is latest. For airplanes 
that have complied with paragraph (g)(2)(ii) of AD 2011-20-07, 
Amendment 39-16818 (76 FR 60710, September 30, 2011), the 
operational test for left center tank fuel boost pump relay R54 and 
right center tank fuel boost pump relay R55 does not apply.
    (5) For AWL No. 28-AWL-23, ``Center Tank Fuel Boost Pump Power 
Failed On Protection System:'' Within 12 months after the date of 
issuance of the original airworthiness certificate or the original 
export certificate of airworthiness, within 12 months after 
accomplishment of the actions specified in Boeing Service Bulletin 
737-28A1248, or within 12 months after the most recent inspection 
was performed as specified in AWL No. 28-AWL-23, whichever is 
latest. This AWL does not apply to airplanes that have complied with 
paragraph (s) of AD 2011-18-03.
    (6) For AWL No. 28-AWL-24, ``Spar Valve Motor Operated Valve 
(MOV) Actuator-Lightning and Fault Current Protection Electrical 
Bond:'' Within 72 months after accomplishment of the actions 
specified in Boeing Service Bulletin 737-28A1207, or

[[Page 26891]]

within 72 months after the most recent inspection was performed as 
specified in AWL No. 28-AWL-24, whichever is later.
    (7) For AWL No. 28-AWL-29, ``Full Cushion Clamps and Teflon 
Sleeving (If Installed) Installed on Out-of-Tank Wire Bundles 
Installed on Brackets that are Mounted Directly on the Fuel Tanks:'' 
For airplanes having line numbers (L/N) 1 through 1754 inclusive, 
within 120 months after accomplishment of the actions specified in 
Boeing Service Bulletin 737-57A1279. For airplanes having L/N 1755 
and subsequent, within 120 months after the date of issuance of the 
original airworthiness certificate or the original export 
certificate of airworthiness, or within 48 months after the 
effective date of this AD, whichever is later.
    (8) For AWL No. 28-AWL-35, ``Fuel Quantity Indicating System 
(FQIS)--Center Fuel Tank In-Tank Component and Wire Harness 
Protection Features--Separation from Center Tank Internal 
Structure:'' For airplanes that have incorporated Boeing Service 
Bulletin 737-28-1356, within 120 months after accomplishment of the 
actions specified in Boeing Service Bulletin 737-28-1356, or within 
120 months after the most recent inspection was performed as 
specified in AWL No. 28-AWL-35, whichever is later.
    (9) For AWL No. 28-AWL-37, ``Fuel Quantity Indicating System 
(FQIS)--Built in Test Equipment (BITE) Test:'' For airplane L/Ns 
6987 and 7000 and subsequent, within 750 flight hours since the date 
the most recent BITE test was accomplished as specified in AWL No. 
28-AWL-37, or within 750 flight hours after the effective date of 
this AD, whichever is later.
    (10) For AWL No. 47-AWL-04, ``Nitrogen Generation System-Thermal 
Switch:'' Within 22,500 flight hours after the date of issuance of 
the original airworthiness certificate or the original export 
certificate of airworthiness, within 22,500 flight hours after 
accomplishment of the actions specified in Boeing Service Bulletin 
737-47-1003, or within 22,500 flight hours after the most recent 
inspection was performed as specified in AWL No. 47-AWL-04, 
whichever is latest.
    (11) For AWL No. 47-AWL-06, ''Nitrogen Generation System (NGS)-
Cross Vent Check Valve:'' Within 13,000 flight hours after the date 
of issuance of the original airworthiness certificate or the 
original export certificate of airworthiness, within 13,000 flight 
hours after accomplishment of the actions specified in Boeing 
Service Bulletin 737-47-1003, or within 13,000 flight hours after 
the most recent inspection was performed as specified in AWL No. 47-
AWL-06, whichever is latest.
    (12) For AWL No. 47-AWL-07, ``Nitrogen Generation System (NGS)-
Nitrogen Enriched Air (NEA) Distribution Ducting Integrity:'' Within 
6,500 flight hours after the date of issuance of the original 
airworthiness certificate or the original export certificate of 
airworthiness, within 6,500 flight hours after accomplishment of the 
actions specified in Boeing Service Bulletin 737-47-1003, or within 
6,500 flight hours after the most recent inspection was performed as 
specified in AWL No. 47-AWL-07, whichever is latest.
    (13) For AWL No. 47-AWL-09, ``Nitrogen Generation System--Oxygen 
Sensor:'' Within 18,000 flight hours after the date of issuance of 
the original airworthiness certificate or the original export 
certificate of airworthiness, or within 18,000 flight hours after 
the most recent replacement was performed as specified in AWL No. 
47-AWL-09, or within 12 months after the effective date of this AD, 
whichever is latest.
    (14) For AWL No. 28-AWL-101, ``Engine Fuel Suction Feed 
Operational Test:'' Within 7,500 flight hours or 36 months, 
whichever occurs first, after the date of issuance of the original 
airworthiness certificate or the original export certificate of 
airworthiness; or within 7,500 flight hours or 36 months, whichever 
occurs first, after the most recent inspection was performed as 
specified in AWL No. 28-AWL-101; whichever is later.

(h) Additional Acceptable Wire Types and Sleeving

    As an option, when accomplishing the actions required by 
paragraph (g) of this AD, the changes specified in paragraphs (h)(1) 
and (2) of this AD are acceptable.
    (1) Where AWL No. 28-AWL-05 identifies wire types BMS 13-48, BMS 
13-58, and BMS 13-60, the following wire types are acceptable: MIL-
W-22759/16, SAE AS22759/16 (M22759/16), MIL-W-22759/32, SAE AS22759/
32 (M22759/32), MIL-W-22759/34, SAE AS22759/34 (M22759/34), MIL-W-
22759/41, SAE AS22759/41 (M22759/41), MIL-W-22759/86, SAE AS22759/86 
(M22759/86), MIL-W-22759/87, SAE AS22759/87 (M22759/87), MIL-W-
22759/92, and SAE AS22759/92 (M22759/92); and MIL-C-27500 and NEMA 
WC 27500 cables constructed from these military or SAE specification 
wire types, as applicable.
    (2) Where AWL No. 28-AWL-05 identifies TFE-2X Standard wall for 
wire sleeving, the following sleeving materials are acceptable: 
Roundit 2000NX and Varglas Type HO, HP, or HM.

(i) No Alternative Actions, Intervals, or Critical Design Configuration 
Control Limitations (CDCCLs)

    Except as provided in paragraph (h) of this AD, after the 
existing maintenance or inspection program has been revised as 
required by paragraph (g) of this AD, no alternative actions (e.g., 
inspections), intervals, or CDCCLs may be used unless the actions, 
intervals, and CDCCLs are approved as an alternative method of 
compliance (AMOC) in accordance with the procedures specified in 
paragraph (k) of this AD.

(j) Terminating Action for Certain AD Requirements

    Accomplishment of the revision required by paragraph (g) of this 
AD terminates the requirements specified in paragraphs (j)(1) 
through (6) of this AD for that airplane.
    (1) The revision required by paragraphs (h) and (h)(1) of AD 
2008-06-03.
    (2) All requirements of AD 2008-10-10 R1.
    (3) The revision required by paragraph (g) of AD 2008-17-15.
    (4) The revision required by paragraph (k) of AD 2011-18-03.
    (5) All requirements of AD 2013-15-17.
    (6) All requirements of AD 2018-20-24.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle 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 (l)(1) of this AD. Information may be 
emailed to: 9-ANM-Seattle-ACO-AMOC-Requests@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) 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 Company Organization Designation 
Authorization (ODA) that has been authorized by the Manager, Seattle 
ACO Branch, FAA, 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.

(l) Related Information

    (1) For more information about this AD, contact Christopher 
Baker, Aerospace Engineer, Propulsion Section, FAA, Seattle ACO 
Branch, 2200 South 216th St., Des Moines, WA 98198; phone and fax: 
206-231-3556; email: Christopher.R.Baker@faa.gov.
    (2) 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 562-797-1717; internet https://www.myboeingfleet.com. You may view this service information at the 
FAA, Airworthiness Products Section, Operational Safety Branch, 2200 
South 216th St., Des Moines, WA. For information on the availability 
of this material at the FAA, call 206-231-3195.

    Issued on April 23, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-09395 Filed 5-5-20; 8:45 am]
 BILLING CODE 4910-13-P