[Federal Register Volume 81, Number 162 (Monday, August 22, 2016)]
[Proposed Rules]
[Pages 56538-56540]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-19935]


 ========================================================================
 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. 81, No. 162 / Monday, August 22, 2016 / 
Proposed Rules  

[[Page 56538]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-8186; Directorate Identifier 2016-NM-074-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 
series airplanes. This proposed AD was prompted by reports of skin 
cracking found at the corners of the aft entry and aft galley doorways. 
This proposed AD would require repetitive inspections for cracking of 
the corners of the aft entry and aft galley doorways; and repair if 
necessary, which would terminate the repetitive inspections of the 
repaired areas. We are proposing this AD to detect and correct cracking 
of the corners of the aft entry and aft galley doorways, which could 
result in rapid decompression and consequent reduced structural 
integrity of the airplane.

DATES: We must receive comments on this proposed AD by October 6, 2016.

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.
     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: Data & Services Management, P.O. Box 
3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-5000, 
extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. 
You may view this referenced service information at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information 
on the availability of this material at the FAA, call 425-227-1221. It 
is also available on the internet at http://www.regulations.gov by 
searching for and locating Docket No. FAA-2016-8186.

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-2016-
8186; or in person at the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this proposed AD, the regulatory evaluation, any comments 
received, and other information. The street address for the Docket 
Office (phone: 800-647-5527) is in the ADDRESSES section. Comments will 
be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Alan Pohl, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6450; fax: 
425-917-6590; email: [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite 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-2016-8186; 
Directorate Identifier 2016-NM-074-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We received reports of skin cracking found at the corners of the 
aft entry and aft galley doorways. These cracks are most common at the 
lower forward corners and the upper aft corners of the doorways, and 
the crack lengths range from 0.25 to 4.50 inches. At the time of crack 
detection, the airplanes had accumulated between 26,896 and 73,655 
total flight cycles. These cracks are caused by fatigue from cyclic 
pressurization of the fuselage combined with increased stress 
concentration due to the proximity of the fastener holes to the corners 
of the doorways. The cracks typically originate at the fastener holes 
and grow towards the corners of the doorways. This condition, if not 
corrected, could result in rapid decompression and consequent reduced 
structural integrity of the airplane.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 737-53A1350, dated May 6, 
2016. The service information describes procedures for, among other 
things, external detailed inspections for cracking of the skin assembly 
of the corners of the aft entry and aft galley doorways, and repair of 
any cracking. 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

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of these same type 
designs.

Proposed AD Requirements

    This proposed AD would require accomplishing the actions specified 
in the service information described previously.

[[Page 56539]]

Explanation of Applicability

    Model 737 airplanes having line numbers 1 through 291 have a limit 
of validity (LOV) of 34,000 total flight cycles. These airplanes have 
accumulated total flight cycles beyond that LOV. Although operation of 
an airplane beyond its LOV is prohibited by 14 CFR 121.1115 and 
129.115, this proposed AD would include those airplanes in the 
applicability so that these airplanes are tracked in the event the LOV 
is extended in the future.

Costs of Compliance

    We estimate that this proposed AD affects 326 airplanes of U.S. 
registry.
    We estimate the following costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                Cost on U.S.
          Action                  Labor cost          Parts cost       Cost per product          operators
----------------------------------------------------------------------------------------------------------------
Inspections...............  22 work-hours x $85                $0   $1,870 per inspection  $609,620 per
                             per hour = $1,870                       cycle.                 inspection cycle.
                             per inspection cycle.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions 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.
    We are 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

    We 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) Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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-2016-8186; Directorate Identifier 
2016-NM-074-AD.

(a) Comments Due Date

    We must receive comments by October 6, 2016.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 737-100, -200, -
200C, -300, -400, and -500 series airplanes; certificated in any 
category; as identified in Boeing Alert Service Bulletin 737-
53A1350, dated May 6, 2016.

(d) Subject

    Air Transport Association (ATA) of America Code 53, Fuselage.

(e) Unsafe Condition

    This AD was prompted by reports of skin cracking found at the 
corners of the aft entry and aft galley doorways. We are issuing 
this AD to detect and correct cracking of the corners of the aft 
entry and aft galley doorways, which could result in rapid 
decompression and consequent reduced structural integrity of the 
airplane.

(f) Compliance

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

(g) Inspections for Group 1 Airplanes

    For airplanes identified as Group 1 in Boeing Alert Service 
Bulletin 737-53A1350, dated May 6, 2016: Within 120 days after the 
effective date of this AD, inspect the airplane using a method 
approved in accordance with the procedures specified in paragraph 
(k) of this AD.

(h) Repetitive Inspections for Groups 2 Through 8 Airplanes

    For airplanes identified as Groups 2 through 8 in Boeing Alert 
Service Bulletin 737-53A1350, dated May 6, 2016: At the applicable 
time specified in paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 737-53A1350, dated May 6, 2016, except as required 
by paragraph (j) of this AD: Do low frequency eddy current and 
detailed inspections for cracking of the aft entry and aft galley 
doorway corners, as applicable, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
53A1350, dated May 6, 2016. Repeat the inspections thereafter at the 
applicable times specified in paragraph 1.E., ``Compliance,'' of 
Boeing Alert Service Bulletin 737-53A1350, dated May 6, 2016.

(i) Repair

    If any crack is found during any inspection required by 
paragraph (h) of this AD, repair before further flight, in 
accordance with Part 3 of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 737-53A1350, dated May 6, 2016. 
Accomplishment of this repair terminates the repetitive inspections 
required by paragraph (h) of this AD for the repaired doorway corner 
location only.

(j) Exception to Service Information Specifications

    Where paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 737-53A1350, dated May 6, 2016, specifies a compliance time 
``after the original issue date of this service bulletin,'' this AD 
requires compliance within the specified compliance time after the 
effective date of this AD.

[[Page 56540]]

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle Aircraft Certification Office (ACO), 
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 ACO, send it to the 
attention of the person identified in paragraph (l)(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 Commercial Airplanes Organization 
Designation Authorization (ODA) that has been authorized by the 
Manager, Seattle ACO, 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.
    (i) For service information that contains steps that are labeled 
as Required for Compliance (RC), the provisions of paragraphs 
(k)(3)(i) and (k)(3)(ii) of this AD apply. The steps labeled as RC, 
including substeps under an RC step and any figures identified in an 
RC step, must be done to comply with the AD. An AMOC is required for 
any deviations to RC steps, including substeps and identified 
figures.
    (ii) Steps not labeled as RC may be deviated from using accepted 
methods in accordance with the operator's maintenance or inspection 
program without obtaining approval of an AMOC, provided the RC 
steps, including substeps and identified figures, can still be done 
as specified, and the airplane can be put back in an airworthy 
condition.

(l) Related Information

    (1) For more information about this AD, contact Alan Pohl, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; 
phone: 425-917-6450; fax: 425-917-6590; email: [email protected].
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. You may view this referenced service 
information at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue SW., Renton, WA. For information on the availability of this 
material at the FAA, call 425-227-1221.

    Issued in Renton, WA, on August 11, 2016.
Paul R. Bernado,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-19935 Filed 8-19-16; 8:45 am]
 BILLING CODE 4910-13-P