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[Federal Register Volume 79, Number 102 (Wednesday, May 28, 2014)]
[Proposed Rules]
[Pages 30500-30503]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-12254]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2014-0284; Directorate Identifier 2014-NM-011-AD]
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: We propose to adopt a new airworthiness directive (AD) for 
certain The Boeing Company Model 737-100, 737-200, 737-200C, 737-300, 
737-400, and 737-500 series airplanes. This proposed AD was prompted by 
reports of cracking in the lower corners of the forward entry doorway 
and the upper corners of the airstairs cutout. This proposed AD would 
require inspections for cracking of the forward entry doorway and 
airstairs cutout, and corrective actions if necessary. This proposed AD 
also provides terminating action for the repetitive inspections. We are 
proposing this AD to detect and correct cracks in the lower corners of 
the forward entry door cutout and the upper corners of the airstairs 
cutout, which could progress and result in an inability to maintain 
cabin pressurization.

DATES: We must receive comments on this proposed AD by July 14, 2014.

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 proposed 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.

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-2014-
0284; 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

[[Page 30501]]

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, ANM-
120S, Seattle Aircraft Certification Office, FAA, 1601 Lind Avenue SW., 
Renton, WA 98057-3356; phone: 425-917-6450; fax: 425-917-6590; email: 
alan.pohl@faa.gov.

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-2014-0284; 
Directorate Identifier 2014-NM-011-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 indicating that during routine inspections, 
cracks were found in the skin and doubler assemblies and bearstraps at 
the forward and aft lower corners of the forward entry doorway. Cracks 
were also found in the forward upper corner of the airstairs cutout. 
Cracks at the aft lower corner of the forward entry door typically 
start at the forward fastener hole that attaches the aft corner scuff 
plate at approximately station 339 and extend downward. Typical cracks 
at the upper forward corner of the airstairs door start near the upper 
tangent point of the corner radius. The airplanes on which the cracks 
were found had accumulated between 24,174 total flight cycles and 
66,173 total flight cycles.
    Since the original issue of Boeing Special Attention Service 
Bulletin 737-53-1083, dated October 28, 1983, 12 operators have 
reported finding cracks between 0.3 and 5.5 inches long on 19 
airplanes. Since Boeing Special Attention Service Bulletin 737-53-1083, 
Revision 3, dated December 7, 1989, was issued, nine operators have 
reported finding cracks between 0.25 and 2.7 inches long in the forward 
entry door cutout on 13 airplanes that were not included in the 
effectivity of that service bulletin. In addition, six operators have 
reported finding cracks between 0.5 and 1.5 inches long in the upper 
forward corner of the airstairs cutout.
    Such cracking, if not corrected, could progress and result in an 
inability to maintain cabin pressurization.

Relevant Service Information

    We reviewed Boeing Special Attention Service Bulletin 737-53-1083, 
Revision 4, dated December 18, 2013. For information on the procedures 
and compliance times, see this service information at http://www.regulations.gov by searching for Docket No. FAA-2014-0284.

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 the same type design.

Proposed AD Requirements

    This proposed AD would require inspections for cracking as 
specified in the service information described previously, except as 
discussed under ``Differences Between this Proposed AD and the Service 
Information.''
    The phrase ``corrective actions'' is used in this proposed AD. 
``Corrective actions'' are actions that correct or address any 
condition found. Corrective actions in an AD could include, for 
example, repairs.

Difference Between This Proposed AD and the Service Information

    Boeing Special Attention Service Bulletin 737-53-1083, Revision 4, 
dated December 18, 2013, specifies to contact the manufacturer for 
instructions on how to repair certain conditions, but this proposed AD 
would require repairing those conditions in one of the following ways:
     In accordance with a method that we approve; or
     Using data that meet the certification basis of the 
airplane, and that have been approved by the Boeing Commercial 
Airplanes Organization Designation Authorization (ODA) whom we have 
authorized to make those findings.

Related Rulemaking

    AD 90-06-02, Amendment 39-6489 (Docket No. 89-NM-67-AD; 55 FR 8372, 
March 7, 1990) mandates certain structural modifications for Boeing 
Model 737 series airplanes. AD 98-11-04 R1, Amendment 39-10984 (64 FR 
987, January 7, 1999); AD 2008-08-23, Amendment 39-15477 (73 FR 21237, 
April 21, 2008); and AD 2008-09-13, Amendment 39-15494 (73 FR 24164, 
May 2, 2008); are supplemental structural inspection (SSI) program ADs 
that contain inspection requirements that are near or overlap the 
inspection areas that this proposed AD would require. The modification 
mandated by AD 90-06-02 and the inspections mandated by the exploratory 
SSI ADs are not sufficient to address the unsafe condition identified 
in this proposed AD.

Clarification of Post-Repair and Post-Preventive Modification 
Repetitive Inspections

    Paragraph (i) and Note 1 to paragraph (i) of this proposed AD 
clarify that the post-repair and post-preventive modification 
repetitive inspections specified in table 4 of paragraph 1.E., 
``Compliance,'' of Boeing Special Attention Service Bulletin 737-53-
1083, Revision 4, dated December 18, 2013, would not be required by 
this proposed AD.

Costs of Compliance

    We estimate that this proposed AD affects 132 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
----------------------------------------------------------------------------------------------------------------
Inspection (Groups 1 through 4    9 work-hours x $85               $0   $765 per inspection  $100,980 per
 airplanes).\1\                    per hour = $765                       cycle.               inspection cycle.
                                   per inspection
                                   cycle.
----------------------------------------------------------------------------------------------------------------
\1\ We have received no definitive data that would enable us to provide cost estimates for the inspection of
  Group 5 airplanes.

[[Page 30502]]

                                                 Optional Costs
----------------------------------------------------------------------------------------------------------------
                Action                        Labor cost               Parts cost            Cost per product
----------------------------------------------------------------------------------------------------------------
Preventive modification..............  Up to 2 work-hours x     Up to $3,927...........  Up to $4,097.
                                        $85 per hour = $170.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary repair that 
would be required based on the results of the proposed inspection. We 
have no way of determining the number of aircraft that might need this 
repair:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                Action                        Labor cost               Parts cost            Cost per product
----------------------------------------------------------------------------------------------------------------
Repair...............................  25 work-hours x $85 per  Up to $5,342...........  Up to $7,467.
                                        hour = $2,125.
----------------------------------------------------------------------------------------------------------------

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. Amend Sec.  39.13 by adding the following new airworthiness 
directive (AD):

The Boeing Company: Docket No. FAA-2014-0284; Directorate Identifier 
2014-NM-011-AD.

(a) Comments Due Date

    We must receive comments by July 14, 2014.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to The Boeing Company Model 737-100, -200, -
200C, -300, -400, and -500 series airplanes, as identified in Boeing 
Special Attention Service Bulletin 737-53-1083, Revision 4, dated 
December 18, 2013.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by reports of cracking in the lower corners 
of the forward entry doorway and the upper corners of the airstairs 
cutout. We are issuing this AD to detect and correct cracks in the 
lower corners of the forward entry door cutout and the upper corners 
of the airstairs cutout, which could progress and result in an 
inability to maintain cabin pressurization.

(f) Compliance

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

(g) Inspections and Corrective Actions

    (1) For airplane Groups 1 through 4, as identified in Boeing 
Special Attention Service Bulletin 737-53-1083, Revision 4, dated 
December 18, 2013: Except as required by paragraphs (j)(1) and 
(j)(2) of this AD, at the applicable time specified in table 1, 2, 
or 3, as applicable, of paragraph 1.E., ``Compliance,'' of Boeing 
Special Attention Service Bulletin 737-53-1083, Revision 4, dated 
December 18, 2013, do the inspections specified in paragraphs 
(g)(1)(i), (g)(1)(ii), (g)(1)(iii), and (g)(1)(iv) of this AD for 
cracks at the forward entry doorway and airstairs cutout, and do all 
applicable corrective actions, in accordance with Parts 1 and 3 of 
the Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 737-53-1083, Revision 4, dated December 18, 2013, except as 
required by paragraph (j)(2) of this AD. Repeat the inspections, 
thereafter, at the interval specified in table 1, 2, or 3, as 
applicable, of paragraph 1.E., ``Compliance,'' of Boeing Special 
Attention Service Bulletin 737-53-1083, Revision 4, dated December 
18, 2013. Do all applicable corrective actions before further 
flight. Any repair done in accordance with Part 3 of the 
Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 737-53-1083, Revision 4, dated December 18, 2013, 
terminates the repetitive inspections required by paragraph (g)(1) 
of this AD for the repaired area only.
    (i) An external detailed and high frequency eddy current (HFEC) 
inspection of the skin.
    (ii) An internal detailed and HFEC inspection of exposed parts 
of the bear strap.
    (iii) A detailed and HFEC inspection along the edge of the 
cutout in the skin, skin doubler, and bear strap.
    (iv) An external low frequency eddy current inspection (LFEC) of 
the skin and bearstrap.
    (2) For Groups 1 and 2 airplanes that have been repaired using 
any of the service information identified in paragraph (g)(2)(i), 
(g)(2)(ii), or (g)(2)(iii) of this AD, the inspections required by 
paragraph (g)(1) of this AD are not required.
    (i) Boeing Service Bulletin 737-53-1083, Revision 1, dated 
October 25, 1985.

[[Page 30503]]

    (ii) Boeing Service Bulletin 737-53-1083, Revision 2, dated 
March 25, 1988.
    (iii) Boeing Service Bulletin 737-53-1083, Revision 3, dated 
December 7, 1989.
    (3) For Group 5 airplanes, as identified in Boeing Special 
Attention Service Bulletin 737-53-1083, Revision 4, dated December 
18, 2013: Within 120 days after the effective date of this AD, 
inspect the forward entry door cutout and airstairs cutout for 
cracks, and repair any crack, using a method approved in accordance 
with the procedures specified in paragraph (k) of this AD.

(h) Optional Preventive Modification

    For Groups 1 and 2, Configurations 5 and 6 airplanes; and Groups 
3 and 4 airplanes; as identified in Boeing Special Attention Service 
Bulletin 737-53-1083, Revision 4, dated December 18, 2013: Except as 
required by paragraph (j)(2) of this AD, accomplishment of the 
preventive modification in accordance with Part 2 of the 
Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 737-53-1083, Revision 4, dated December 18, 2013, 
terminates the inspections required by paragraph (g)(1) of this AD.

(i) Post-Modification and Post-Repair Repetitive Inspections

    The post-modification and post-repair repetitive inspections 
specified in table 4 of paragraph 1.E., ``Compliance,'' of Boeing 
Special Attention Service Bulletin 737-53-1083, Revision 4, dated 
December 18, 2013, are not required by this AD.

    Note 1 to paragraph (i) of this AD:  The inspections specified 
in table 4 of paragraph 1.E., ``Compliance,'' of Boeing Special 
Attention Service Bulletin 737-53-1083, Revision 4, dated December 
18, 2013, may be used in support of compliance with Section 
121.1109(c)(2) or 129.109(b)(2) of the Federal Aviation Regulations 
(14 CFR 121.1109(c)(2) or 14 CFR 129.109(b)(2)). The corresponding 
actions specified in the Accomplishment Instructions of Boeing 
Special Attention Service Bulletin 737-53-1083, Revision 4, dated 
December 18, 2013, are not required by this AD.

(j) Exceptions to Service Information Specifications

    (1) Where Boeing Special Attention Service Bulletin 737-53-1083, 
Revision 4, dated December 18, 2013, specifies a compliance time 
``after the Revision 4 date of this service bulletin,'' this AD 
requires compliance within the specified compliance time after the 
effective date of this AD.
    (2) Where Boeing Special Attention Service Bulletin 737-53-1083, 
Revision 4, dated December 18, 2013, specifies to contact Boeing for 
repair instructions, this AD requires repair before further flight 
using a method approved in accordance with the procedures specified 
in paragraph (k) of this AD.

(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: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (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 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. For a repair method to be approved, the repair must 
meet the certification basis of the airplane, and the approval must 
specifically refer to this AD.

(l) Related Information

    (1) For more information about this AD, contact Alan Pohl, 
Aerospace Engineer, ANM-120S, Seattle Aircraft Certification Office, 
FAA, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-
6450; fax: 425-917-6590; email: alan.pohl@faa.gov.
    (2) For service information identified in this AD, 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.

    Issued in Renton, Washington, on May 16, 2014.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2014-12254 Filed 5-27-14; 8:45 am]
BILLING CODE 4910-13-P
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