[Federal Register Volume 86, Number 35 (Wednesday, February 24, 2021)]
[Rules and Regulations]
[Pages 11106-11108]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-03598]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-1021; Project Identifier AD-2020-00847-T; 
Amendment 39-21412; AD 2021-03-09]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
The Boeing Company Model 727 series airplanes. This AD was prompted by 
a determination that excessive sealant coating on internal wing 
Structural Significant Items (SSIs) may not reveal cracks during 
inspections required by AD 98-11-03 R1. This AD requires revising the 
existing maintenance or inspection program, as applicable, to 
incorporate inspections that will give no less than the required damage 
tolerance rating (DTR) for certain SSIs of the wing. This AD also 
requires repetitive inspections for cracking of the affected SSIs and 
repair if necessary. The FAA is issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective March 31, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of March 31, 
2021.

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 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. It is also available on 
the internet at https://www.regulations.gov by searching for and 
locating Docket No. FAA-2020-1021.

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-
1021; 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, 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: Mohit Garg, Aerospace Engineer, 
Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount 
Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5264; 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 all The Boeing Company 
Model 727 airplanes. The NPRM published in the Federal Register on 
November 27, 2020 (85 FR 75969). The NPRM was prompted by a 
determination that excessive sealant coating on internal wing SSIs may 
not reveal cracks during inspections required by AD 98-11-03 R1, 
Amendment 39-10983 (64 FR 989, January 7, 1999) (AD 98-11-03 R1). The 
NPRM proposed to require revising the existing maintenance or 
inspection program, as applicable, to incorporate inspections that will 
give no less than the required DTR for certain SSIs of the wing. The 
NPRM also proposed to require repetitive inspections for cracking of 
the affected SSIs and repair if necessary.
    The FAA is issuing this AD to address excessive sealant coating on 
internal wing SSIs that may prevent the detection of cracks during 
inspections. This condition, if not addressed, could result in 
propagation of structural cracks that could lead to the inability of a 
wing SSI to sustain limit load and result in loss of control of the 
airplane.

Comments

    The FAA gave the public the opportunity to participate in 
developing this final rule. The FAA has considered the comment 
received. Boeing indicated its support for the NPRM.

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 as proposed, except for 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

[[Page 11107]]

     Do not add any additional burden upon the public than was 
already proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing 727 Supplemental Structural Inspection 
Document D6-48040-1, Volume I, Temporary Revision 08-1001, dated 
February 2020; and Boeing 727 Supplemental Structural Inspection 
Document D6-48040-1, Volume II, Temporary Revision 11-1001, dated 
February 2020. In combination, this service information describes 
repetitive inspections for cracking of internal wing SSIs. 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 40 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:
    The FAA has 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 has 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 has 
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).

                                                Estimated Costs *
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                                                                                                 Cost on U.S.
             Action                      Labor cost          Parts cost   Cost per  product        operators
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Inspections.....................  48 work-hours x $85 per            $0  $4,080 per           $163,200 per
                                   hour = $4,080 per                      inspection cycle.    inspection cycle.
                                   inspection cycle.
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* Table does not include estimated costs for revising the existing maintenance or inspection program.

    The FAA has received no definitive data on which to base the 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:

2021-03-09 The Boeing Company: Amendment 39-21412 ; Docket No. FAA-
2020-1021; Project Identifier AD-2020-00847-T.

(a) Effective Date

    This airworthiness directive (AD) is effective March 31, 2021.

(b) Affected Airworthiness Directives (ADs)

    This AD affects AD 98-11-03 R1, Amendment 39-10983 (64 FR 989, 
January 7, 1999) (AD 98-11-03 R1).

(c) Applicability

    This AD applies to all The Boeing Company 727, 727C, 727-100, 
727-100C, 727-200, and 727-200F 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 determination that excessive sealant 
coating on internal wing Structural Significant Items (SSIs) may not 
reveal cracks during inspections required by AD 98-11-03 R1. The FAA 
is issuing this AD to address excessive sealant coating on internal 
wing SSIs that may prevent the detection of cracks during 
inspections. This condition, if not addressed, could result in 
propagation of structural cracks that could lead to the inability of 
a wing SSI to sustain limit load and result in loss of control of 
the airplane.

(f) Compliance

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

(g) Maintenance or Inspection Program Revision, Repetitive Inspections, 
and Repair

    (1) Prior to reaching the applicable time specified in paragraph 
(g)(2)(i) or (ii) of this AD, incorporate a revision into the 
existing maintenance or inspection program, as applicable, that 
provides no less than the required damage tolerance rating (DTR) for 
each SSI of the wing listed in Boeing 727 Supplemental Structural 
Inspection Document D6-48040-1, Volume I, Temporary Revision 08-
1001, dated February 2020; and Boeing 727 Supplemental

[[Page 11108]]

Structural Inspection Document D6-48040-1, Volume II, Temporary 
Revision 11-1001, dated February 2020.
    (2) At the applicable time specified in paragraph (g)(2)(i) or 
(ii) of this AD, perform initial inspections to detect cracks in the 
SSIs identified in Boeing 727 Supplemental Structural Inspection 
Document D6-48040-1, Volume I, Temporary Revision 08-1001, dated 
February 2020; and Boeing 727 Supplemental Structural Inspection 
Document D6-48040-1, Volume II, Temporary Revision 11-1001, dated 
February 2020.
    (i) For Model 727-100C and 727-200F series airplanes: Inspect 
prior to the accumulation of 46,000 total flight cycles, or within 
12 months after the effective date of this AD, whichever occurs 
later.
    (ii) For all airplanes except for those airplanes identified in 
paragraph (g)(2)(i) of this AD: Inspect prior to the accumulation of 
55,000 total flight cycles, or within 3,000 flight cycles measured 
from the date 12 months after the effective date of this AD, 
whichever occurs later.
    (3) At the intervals specified in in Boeing 727 Supplemental 
Structural Inspection Document D6-48040-1, Volume I, Temporary 
Revision 08-1001, dated February 2020; and Boeing 727 Supplemental 
Structural Inspection Document D6-48040-1, Volume II, Temporary 
Revision 11-1001, dated February 2020, as applicable, repeat the 
inspections required by paragraph (g)(2) of this AD.
    (4) If any cracked structure is found during any inspections 
required by paragraph (g) of this AD, repair before further flight 
using an FAA-approved method or using a method approved in 
accordance with the procedures specified in paragraph (j) of this 
AD. Within 12 months after repair, incorporate a revision into the 
maintenance or inspection program, as applicable, to include a 
damage-tolerance-based alternative inspection program for the 
repaired structure. Thereafter, inspect the affected structure in 
accordance with the alternative program. The inspection method and 
compliance times (i.e., threshold and repetitive intervals) of the 
alternative program must be approved in accordance with the 
procedures specified in paragraph (j) of this AD.

(h) No Alternative Actions or Intervals

    After the existing maintenance or inspection program has been 
revised as required by paragraph (g)(1) of this AD, no alternative 
actions (e.g., inspections) or intervals may be used unless the 
actions or intervals are approved as an alternative method of 
compliance (AMOC) in accordance with the procedures specified in 
paragraph (j) of this AD.

(i) Terminating Action for Certain Inspections Required by AD 98-11-03 
R1

    Accomplishing the revision required by paragraph (g)(1) of this 
AD and the initial inspections identified in Boeing 727 Supplemental 
Structural Inspection Document D6-48040-1, Volume I, Temporary 
Revision 08-1001, dated February 2020; and Boeing 727 Supplemental 
Structural Inspection Document D6-48040-1, Volume II, Temporary 
Revision 11-1001, dated February 2020, as required by paragraph 
(g)(2) of this AD, terminate the corresponding SSI inspections 
specified in Boeing Document No. D6-48040-1, Volumes 1 and 2, 
``Supplemental Structural Inspection Document'' (SSID), Revision H, 
dated June 1994, as required by AD 98-11-03 R1.

(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: [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.
    (4) AMOCs approved previously for AD 98-11-03 R1 are approved as 
AMOCs for the corresponding provisions of this AD for the SSIs 
identified in Boeing 727 Supplemental Structural Inspection Document 
D6-48040-1, Volume I, Temporary Revision 08-1001, dated February 
2020; and Boeing 727 Supplemental Structural Inspection Document D6-
48040-1, Volume II, Temporary Revision 11-1001, dated February 2020.

(k) Related Information

    For more information about this AD, contact Mohit Garg, 
Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5264; fax: 562-627-5210; email: [email protected].

(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 727 Supplemental Structural Inspection Document D6-
48040-1, Volume I, Temporary Revision 08-1001, dated February 2020.
    (ii) Boeing 727 Supplemental Structural Inspection Document D6-
48040-1, Volume II, Temporary Revision 11-1001, dated February 2020.
    (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 562-797-1717; internet https://www.myboeingfleet.com.
    (4) 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.
    (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 28, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-03598 Filed 2-23-21; 8:45 am]
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