DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2019-0399; Product Identifier 2018-NM-149-AD]
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 all The Boeing Company Model 737 series airplanes, except for Model
737-100, -200, -200C, -300, -400, and -500 series airplanes. This
proposed AD was prompted by reports of separation of the lower aft
wing-to-body fairing panel 194E ("fairing panel 194E") during flight,
due to worn or damaged nutplates on the support structure. This
proposed AD would require repetitive inspections of fairing panel 194E,
wheel well panel 193D, and support structure for discrepancies, and
related investigative and corrective actions if necessary. This
proposed AD would also require rework of the panels and support
structure, which would terminate the repetitive inspections. 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 August 5, 2019.
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.
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 referenced service information at the FAA, Transport
Standards Branch, 2200 South 216th St., Des Moines, WA. For information
on the availability of this material at the FAA, call 206-231-3195. It
is also available on the internet at http://www.regulations.gov by
searching for and locating Docket No. FAA-2019-0399.
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-2019-
0399; 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, the regulatory evaluation, 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: Alan Pohl, Aerospace Engineer,
Airframe Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des
Moines, WA 98198; phone and fax: 206-231-3527; email:
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-2019-0399;
Product Identifier 2018-NM-149-AD" at the beginning of your comments.
The FAA specifically invites comments on the overall regulatory,
economic, environmental, and energy aspects of this NPRM. The agency
will consider all comments received by the closing date and may amend
this NPRM because of those comments.
The FAA will post all comments, without change, to http://www.regulations.gov,
including any personal information you provide.
The FAA will also post a report summarizing each substantive verbal
contact the agency receives about this NPRM.
The FAA has received several reports of separation of the lower aft
wing-to-body fairing panel 194E during flight. In two of these reports,
damage from the separation of that panel was also found on an adjacent
fairing panel. In another report, the panel was found loose. The
airplanes with loose or missing panels had accumulated between 1,270
and 43,200 total flight hours, and between 550 and 15,800 total flight
cycles. The FAA determined that the nutplates common to the forward
edge of the panel could become worn or damaged. In addition, worn or
damaged nutplates on the support structure for the wheel well panel
193D, which is adjacent to the 194E fairing panel, may also be a
contributing factor to the loss of the 194E fairing panel. This
condition, if not addressed, could result in separation of fairing
Related Service Information Under 1 CFR Part 51
The FAA reviewed Boeing Service Bulletin 737-53-1307, dated January
12, 2012. This service information describes procedures for repetitive
inspections of fairing panel 194E, wheel well panel 193D, and support
structure for discrepancies (including incorrect torque at the
fasteners and worn and damaged nutplates and fastener holes) and
corrective actions (including repair and replacement of nutplates and
fasteners). This service information also describes procedures for
rework of the panels and support structure, including related
investigative actions (general visual inspection of the panel and
support structure for damage) and repair, which together would
eliminate the need for the repetitive inspections.
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.
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
Proposed AD Requirements
This proposed AD would require accomplishing the actions specified
in the service information described previously, except as discussed
under "Differences Between this Proposed AD and the Service
Information," and except for any differences identified as exceptions
in the regulatory text of this proposed AD.
For information on the procedures and compliance times, see this
service information at http://www.regulations.gov by searching for and
locating Docket No. FAA-2019-0399.
The phrase "related investigative actions" is used in this
proposed AD. Related investigative actions are follow-on actions that
(1) are related to the primary action, and (2) further investigate the
nature of any condition found. Related investigative actions in an AD
could include, for example, inspections.
The phrase "corrective actions" is used in this proposed AD.
Corrective actions correct or address any condition found. Corrective
actions in an AD could include, for example, repairs.
Differences Between This Proposed AD and the Service Information
The effectivity of Boeing Service Bulletin 737-53-1307, dated
January 12, 2012, is limited to Model 737-600, -700, -700C, -800, -900,
and -900ER series airplanes, line numbers 1 through 3532 inclusive.
However, the applicability of this proposed AD includes all Model 737
airplanes except for Model 737-100, -200, -200C, -300, -400, and -500
series airplanes. The FAA has determined, as has the design approval
holder, that affected parts can be installed on future deliveries.
Because the affected parts are rotable, the FAA has determined that
these parts could later be installed on airplanes that were initially
delivered with acceptable parts, thereby subjecting those airplanes to
the unsafe condition.
Airplanes from line number 3533 through any airplane with an
original airworthiness certificate or an original export certificate of
airworthiness dated on or before the effective date of this AD would be
subject to the initial inspection requirement of this proposed AD, but
the inspection would not be required to be repeated if the airplane can
be demonstrated to have the post-reworked configuration of Boeing
Service Bulletin 737-53-1307, dated January 12, 2012, as specified in
paragraph (h) of this AD. (Note that the "Parts Installation
Limitation" specified in paragraph (i) of this AD would still apply.)
Costs of Compliance
The FAA estimates that this proposed AD would affect 983 airplanes
of U.S. registry. The agency estimates the following costs to comply
with this proposed AD:
COST PER PRODUCT
COST ON U.S.
|| 8 work-hours x $85 per hour = $680 per inspection cycle.
| $680 per inspection cycle.
|| Up to $668,440 per inspection cycle.
|| 25 work-hours x $85 per hour = $2,125.
|| Up to $2,088,875.
The FAA has received no definitive data that would enable the
agency to provide cost estimates for the on-condition repairs specified
in this proposed AD.
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
This proposed 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 and associated appliances to the
Director of the System Oversight Division.
The FAA has 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
For the reasons discussed above, I certify this proposed regulation:
(1) Is not a "significant regulatory action" under Executive
(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
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.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by adding the following new airworthiness