[Federal Register Volume 85, Number 229 (Friday, November 27, 2020)]
[Proposed Rules]
[Pages 75969-75971]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-25614]



[[Page 75969]]

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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]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all The Boeing Company Model 727 series airplanes. This proposed 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 proposed AD would 
require 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 proposed AD would also require repetitive inspections for cracking 
of the affected SSIs and repair if necessary. 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 January 11, 
2021.

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-
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 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: 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:

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-2020-1021; 
Project Identifier AD-2020-00847-T'' at the beginning of your comments. 
The most helpful comments reference a specific portion of the proposal, 
explain the reason for any recommended change, and include supporting 
data. The FAA will consider all comments received by the closing date 
and may amend the proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact received about this proposed AD.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this NPRM contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this NPRM, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this NPRM. Submissions containing CBI should be sent to 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]. Any commentary 
that the FAA receives which is not specifically designated as CBI will 
be placed in the public docket for this rulemaking.

Discussion

    The FAA has determined that excessive sealant coating on internal 
wing SSIs may prevent the detection of cracks during inspections 
required by AD 98-11-03 R1, Amendment 39-10983 (64 FR 989, January 7, 
1999) (AD 98-11-03 R1) for The Boeing Company Model 727 airplanes. AD 
98-11-03 R1 refers to Boeing Document No. D6-48040-1, Volumes 1 and 2, 
``Supplemental Structural Inspection Document'' (SSID), Revision H, 
dated June 1994, as the appropriate source of service information for 
the required inspections. Boeing SSID document No. D6-48040-1, Revision 
H, dated June 1994, assumes that wing structural components such as 
fastener caps, splice plates, splice fittings stringers, collars, 
chords, webs, and wing skins are accessible for nondestructive testing 
(NDT), general visual (GVI) and detailed (DET) internal inspections. An 
investigation determined excessive sealant might have been applied 
during production on The Boeing Company Model 727 airplanes and might 
prevent the detection of cracks during SSI 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.

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

[[Page 75970]]

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.

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 inspections that will 
give no less than the required DTR for certain SSIs of the wing. This 
proposed AD would also require repetitive inspections for cracking of 
the affected SSIs and repair if necessary.
    This proposed AD does not supersede AD 98-11-03 R1. Rather, the FAA 
has determined that a stand-alone AD would be more appropriate to 
address the changes.
    Accomplishing the revision required by paragraph (g)(1) of this 
proposed AD and the accomplishing the initial inspections required by 
paragraph (g)(2) of this proposed AD, which are 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, would 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. All other SSI inspections specified in the SSID document, 
dated June 1994, that do not specifically correspond to SSID 
inspections referenced in the SSID documents, dated February 2020, 
remain fully applicable and must be complied with accordingly.

Costs of Compliance

    The FAA estimates that this proposed AD affects 40 airplanes of 
U.S. registry. The FAA estimates the following costs to comply with 
this proposed 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
----------------------------------------------------------------------------------------------------------------
Inspections...........  48 work-hours x $85 per                 $0  $4,080 per inspection  $163,200 per
                         hour = $4,080 per                           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 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 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:

The Boeing Company: Docket No. FAA-2020-1021; Project Identifier AD-
2020-00847-T.

(a) Comments Due Date

    The FAA must receive comments by January 11, 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.

[[Page 75971]]

(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 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.
    (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), intervals, may be used unless the 
actions, 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)(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.
    (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

    (1) 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].
    (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 November 5, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-25614 Filed 11-25-20; 8:45 am]
BILLING CODE 4910-13-P