[Federal Register Volume 85, Number 29 (Wednesday, February 12, 2020)]
[Rules and Regulations]
[Pages 7865-7868]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-02719]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2019-0670; Product Identifier 2019-NM-104-AD; Amendment
39-19830; AD 2020-02-16]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain The Boeing Company Model 737-200, -200C, -300, -400, and -500
series airplanes. This AD was prompted by an evaluation by the design
approval holder (DAH) indicating that the lower skin of the fuselage
skin lap splices along the lower fastener row of a certain stringer lap
splice on certain body station skin panels may be subject to widespread
fatigue damage (WFD). This AD requires inspections of the lower skin of
the fuselage skin lap splices along the lower fastener row of a certain
stringer lap splice on certain body station skin panels and applicable
on-condition actions. The FAA is issuing this AD to address the unsafe
condition on these products.
DATES: This AD is effective March 18, 2020.
The Director of the Federal Register approved the incorporation by
reference
[[Page 7866]]
of a certain publication listed in this AD as of March 18, 2020.
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; phone: 562-797-1717; internet: https://www.myboeingfleet.com. You may view this 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 https://www.regulations.gov by searching for and locating Docket No. FAA-2019-
0670.
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-2019-
0670; 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 final rule, the regulatory evaluation, any comments received, and
other information. The address for Docket Operations is 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: James Guo, Aerospace Engineer,
Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount
Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5357; fax: 562-627-
5210; email: [email protected].
SUPPLEMENTARY INFORMATION:
Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain The Boeing
Company Model 737-200, -200C, -300, -400, and -500 series airplanes.
The NPRM published in the Federal Register on September 4, 2019 (84 FR
46496). The NPRM was prompted by a report that an operator of a Model
737-300 airplane discovered a crack in the skin at a chem-milled step
at body station (STA) 727B+10, just above stringer (S)-14R. The
airplane had accumulated 88,805 flight hours and 65,804 flight cycles
at the time the crack was found. Upon further inspection in the local
area using high frequency eddy current (HFEC) hole probe inspection,
multiple fastener hole cracks were found in the S-14 lap splice lower
row in the lower skin between STA 727A and STA 727E. The lower skin at
S-14 is structure that may be susceptible to WFD and may also have
scratches that can propagate into cracks. The scratch cracks may
interact with fatigue cracking. The NPRM proposed to require
inspections of the lower skin of the fuselage skin lap splices along
the lower fastener row of a certain stringer lap splice on certain body
station skin panels and applicable on-condition actions.
The FAA is issuing this AD to address scratch cracks and fatigue
cracking, which may interact and could result in rapid decompression
and loss of structural integrity of the airplane.
Comments
The FAA gave the public the opportunity to participate in
developing this final rule. The following presents the comments
received on the NPRM and the FAA's response to each comment.
Support for the NPRM
Priscilla Suarez expressed support for the NPRM, as well as support
for additional safety inspections, and stricter regulations that
increase safety.
Effect of Winglets on Accomplishment of the Proposed Actions
Aviation Partners Boeing stated that accomplishing Supplemental
Type Certificate (STC) ST01219SE does not affect the actions specified
in the proposed AD.
The FAA concurs with the commenter. The FAA has redesignated
paragraph (c) of the proposed AD as paragraph (c)(1) of this AD and
added paragraph (c)(2) to this AD to state that installation of STC
ST01219SE does not affect the ability to accomplish the actions
required by this AD. Therefore, for airplanes on which STC ST01219SE is
installed, a ``change in product'' alternative method of compliance
(AMOC) approval request is not necessary to comply with the
requirements of 14 CFR 39.17.
Request To Specify That the Airplane May Be Subject to the Unsafe
Condition
Boeing requested that the FAA revise the SUMMARY, Discussion
section, and paragraph (e) in the regulatory text of the NPRM to
specify that the lap splice on certain body station skin panels may be
subject to widespread fatigue damage WFD. Boeing pointed out that the
change would maintain consistency with the wording used in the service
information. Boeing also mentioned that WFD has not been specifically
demonstrated in the subject areas.
The FAA agrees for the reasons provided and has revised this AD
accordingly.
Request To Revise the Unsafe Condition
Boeing requested that the FAA revise the unsafe condition statement
throughout the NPRM to specify only that it could result in rapid
decompression, and remove ``. . . or loss of structural integrity of
the airplane,'' as an additional consequent result. Boeing pointed out
that the change would maintain consistency with the wording in the
service information.
The FAA partially agrees. The FAA agrees that the wording of the
unsafe condition could be confusing and that clarification is
necessary. Therefore, the FAA has changed the unsafe condition
statement to specify that this AD addresses ``. . . scratch cracks and
fatigue cracking, which may interact and could result in rapid
decompression and loss of structural integrity of the airplane.''
Request To Remove Language Regarding Fatigue Damage
Boeing requested that the FAA remove language regarding fatigue
damage and multiple-site damage (MSD) from the Discussion section of
the NPRM. Boeing stated that the information is confusing, provides no
additional understanding of the issues, and that other AD's related to
lap splice scratch cracking and MSD do not include the same
information. Boeing argued that the remaining portions of the
discussion are sufficient with the intent of the NPRM.
The FAA does not agree, because the language identified by Boeing
is not carried forward into the final rule. The FAA acknowledges that
the language regarding fatigue damage and MSD is not present in all ADs
related to lap splice cracking; however, this specific language is
present in other ADs that are related to MSD. This wording helps define
the terms, provides general explanation of the issue, and has not been
demonstrated as confusing. The FAA has not changed this AD in this
regard.
Request for Clarification of the Terminating Action
Boeing requested that the FAA revise paragraph (i) of the proposed
AD to clarify if the proposed terminating action is applicable to ``the
corresponding locations'' or ``the inspections'' in the corresponding
locations. Boeing pointed out that rearranging the statement would make
it grammatically clear whether actions or
[[Page 7867]]
locations are being terminated. Otherwise, Boeing pointed out that the
statement could be misread to interpret it to mean terminating the
locations required by the NPRM.
The FAA agrees for the reasons provided and has revised paragraph
(i) of this AD accordingly.
Conclusion
The FAA 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. The FAA has determined that these minor
changes:
Are consistent with the intent that was proposed in the
NPRM for addressing the unsafe condition; and
Do not add any additional burden upon the public than was
already proposed in the NPRM.
The FAA 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
The FAA has reviewed Boeing Alert Requirements Bulletin 737-53A1382
RB, dated May 6, 2019. This service information describes procedures
for detailed inspections for previous repairs, and repetitive dual
frequency eddy current (DFEC) inspections for cracks of the lower skin
of the fuselage skin lap splices along the lower fastener row of the S-
14 lap splice at specified locations on the STA 727 to STA 908 skin
panel in areas not inspected as specified in other service bulletins,
and applicable on-condition actions. On-condition actions include open
hole HFEC inspections for cracks, and repair. 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
The FAA estimates that this AD affects 158 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
Estimated Costs for Required Actions
----------------------------------------------------------------------------------------------------------------
Cost on U.S.
Action Labor cost Parts cost Cost per product operators
----------------------------------------------------------------------------------------------------------------
DFEC Inspections of S-14 Lap 18 work-hours x $85 $0 $1,530 per $241,740 per
Splices. per hour = $1,530 inspection cycle. inspection cycle.
per inspection
cycle.
----------------------------------------------------------------------------------------------------------------
The FAA estimates the following costs to do any necessary on-
condition inspections that would be required. The FAA has no way of
determining the number of aircraft that might need these on-condition
actions:
Estimated Costs of On-Condition Actions
----------------------------------------------------------------------------------------------------------------
Cost per
Labor cost Parts cost product
----------------------------------------------------------------------------------------------------------------
97 work-hours x $85 per hour = $8,245......................................... $0 $8,245
----------------------------------------------------------------------------------------------------------------
The FAA has received no definitive data that would enable us to
provide cost estimates for the on-condition repairs specified in this
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
rulemaking action.
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) 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.
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
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):
2020-02-16 The Boeing Company: Amendment 39-19830; Docket No. FAA-
2019-0670; Product Identifier 2019-NM-104-AD.
(a) Effective Date
This AD is effective March 18, 2020.
(b) Affected ADs
None.
[[Page 7868]]
(c) Applicability
(1) This AD applies to The Boeing Company Model 737-200, -200C,
-300, -400, and -500 series airplanes, certificated in any category,
as identified in Boeing Alert Requirements Bulletin 737-53A1382 RB,
dated May 6, 2019.
(2) Installation of Supplemental Type Certificate (STC)
ST01219SE does not affect the ability to accomplish the actions
required by this AD. Therefore, for airplanes on which STC ST01219SE
is installed, a ``change in product'' alternative method of
compliance (AMOC) approval request is not necessary to comply with
the requirements of 14 CFR 39.17.
(d) Subject
Air Transport Association (ATA) of America Code 53, Fuselage.
(e) Unsafe Condition
This AD was prompted by an evaluation by the design approval
holder (DAH) indicating that the lower skin of the fuselage skin lap
splices along the lower fastener row of the stringer (S)-14 lap
splice on certain body station skin panels may be subject to
widespread fatigue damage (WFD). The FAA is issuing this AD to
address scratch cracks and fatigue cracking, which may interact and
could result in rapid decompression and loss of structural integrity
of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
Except as specified by paragraph (h) of this AD: At the
applicable times specified in the ``Compliance'' paragraph of Boeing
Alert Requirements Bulletin 737-53A1382 RB, dated May 6, 2019, do
all applicable actions identified in, and in accordance with, the
Accomplishment Instructions of Boeing Alert Requirements Bulletin
737-53A1382 RB, dated May 6, 2019.
Note 1 to paragraph (g): Guidance for accomplishing the actions
required by this AD can be found in Boeing Alert Service Bulletin
737-53A1382, dated May 6, 2019, which is referred to in Boeing Alert
Requirements Bulletin 737-53A1382 RB, dated May 6, 2019.
(h) Exceptions to Service Information Specifications
(1) Where Boeing Alert Requirements Bulletin 737-53A1382 RB,
dated May 6, 2019, uses the phrase ``the original issue date of
Requirements Bulletin 737-53A1382 RB,'' this AD requires using ``the
effective date of this AD.''
(2) Where Boeing Alert Requirements Bulletin 737-53A1382 RB,
dated May 6, 2019, specifies contacting Boeing for repair
instructions or for alternative inspections: This AD requires doing
the repair, or doing the alternative inspections and applicable on-
condition actions using a method approved in accordance with the
procedures specified in paragraph (j) of this AD.
(i) Terminating Action for the Required Inspections
Accomplishment of certain skin panel replacements identified as
terminating action in Boeing Alert Requirements Bulletin 737-53A1382
RB, dated May 6, 2019, terminates the inspections required by this
AD, in the corresponding locations.
(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)(1) of this AD. Information
may be emailed to: [email protected].
(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, Los
Angeles 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.
(k) Related Information
(1) For more information about this AD, contact James Guo,
Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch,
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5357; fax: 562-627-5210; email: [email protected].
(2) Service information identified in this AD that is not
incorporated by reference is available at the addresses specified in
paragraphs (l)(3) and (4) of this AD.
(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 Alert Requirements Bulletin 737-53A1382 RB, dated May
6, 2019.
(ii) [Reserved]
(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; phone: 562-797-1717; internet: https://www.myboeingfleet.com.
(4) You may view this 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.
(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, email [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.
Issued on January 27, 2020.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness
Division, Aircraft Certification Service.
[FR Doc. 2020-02719 Filed 2-11-20; 8:45 am]
BILLING CODE 4910-13-P