
[Federal Register: April 15, 2010 (Volume 75, Number 72)]
[Proposed Rules]
[Page 19564-19567]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr15ap10-15]

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Proposed Rules
                                                Federal Register
________________________________________________________________________

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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[[Page 19564]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0036; Directorate Identifier 2009-NM-077-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Model 737-200, -
200C, -300, -400, and- 500 Series Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to adopt a new airworthiness directive (AD) for
certain Model 737-200, -200C, -300, -400, and- 500 series airplanes.
This proposed AD would require repetitive inspections for cracking and
corrosion of the skin and surrounding structure under the number 3 very
high frequency (VHF) antenna, and corrective actions if necessary.
Also, for certain airplanes, this proposed AD would require replacing
bonded skin panels with solid skin panels. This proposed AD results
from reports of cracks in the skin and surrounding structure under the
number 3 VHF antenna on the lower external surface of the airplane at
Buttock Line 0.0, aft of the main landing gear wheel well. We are
proposing this AD to detect and correct cracks and corrosion of the
skin and surrounding structure under the number 3 VHF antenna, which
could result in separation of the antenna from the airplane, and rapid
depressurization of the airplane.

DATES: We must receive comments on this proposed AD by June 1, 2010.

ADDRESSES: You may send comments 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: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE., Washington, DC 20590, 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, Washington 98124-2207; telephone 206-
544-5000, extension 1; fax 206-766-5680; e-mail me.boecom@boeing.com;
Internet https://www.myboeingfleet.com. You may review copies of the
referenced service information at the FAA, Transport Airplane
Directorate, 1601 Lind Avenue SW., Renton, Washington. 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; 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 (telephone 800-647-5527) is in the
ADDRESSES section. Comments will be available in the AD docket shortly
after receipt.

FOR FURTHER INFORMATION CONTACT: Wayne Lockett, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6447; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or
arguments about this proposed AD. Send your comments to an address
listed under the ADDRESSES section. Include ``Docket No. FAA-2010-0036;
Directorate Identifier 2009-NM-077-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 have received reports of cracks of the skin and surrounding
structure under the number 3 (very high frequency) VHF antenna on the
lower external surface of the airplane at Buttock Line 0.0, aft of the
main landing gear wheel well on Model 737-200, -200C, -300, -400, and-
500 series airplanes. One report indicated there was a 15-inch
longitudinal crack in the skin near Buttock Line 0.0 just forward of
the number 3 VHF antenna cutout, running forward. The first 14 inches
of the crack was hidden beneath the number 3 VHF antenna. Five other
reports indicated there were skin cracks between 1.5 and 3 inches in
length in the same area. The reports also indicated that the main
antenna support channel and other support structure were cracked. The
earliest reported cracks were at 18,289 flight cycles. This condition,
if not corrected, could result in crack growth, possibly leading to
separation of the antenna from the airplane, and rapid depressurization
of the airplane.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletin 737-53-
1287, dated March 11, 2009. The service bulletin describes procedures
for repetitive external detailed and external high frequency eddy
current (HFEC) inspections for cracking and corrosion in the skin; and
repetitive internal detailed inspections for cracking and corrosion in
the skin, antenna support structure, and surrounding frames and
stringers; depending on the airplane configuration. For Group 1-4,
configuration 2 airplanes, having a cover plate at the number 3 VHF
antenna location, accomplishing the HFEC inspection eliminates the need
for repetitive external detailed inspections.
    Boeing Special Attention Service Bulletin 737-53-1287, dated March
11, 2009, also specifies contacting Boeing

[[Page 19565]]

for certain inspection instructions, and for all repair instructions.
    The initial compliance time is 15,000 total flight cycles, or
within 1,100 or 6,000 flight cycles (depending on configuration and
inspection type) from the date on the service bulletin, whichever
occurs later, for the following inspections:
     External detailed inspections for any crack in the skin;
     External HFEC inspections for any crack in the skin;
     Internal detailed inspection for any crack in the skin,
antenna support structure, and surrounding frames and stringers; and
     Internal detailed inspection for any crack or corrosion in
the skin, antenna support structure, and surrounding frames and
stringers.
    The initial compliance time is within 18,000 flight cycles
(depending on configuration and inspection type) from the date on the
service bulletin, for the following inspections:
     External detailed and HFEC inspection for any crack or
corrosion in the skin; and
     Internal detailed inspection for any crack or corrosion in
the skin.
    The repetitive inspection intervals, which depend on the airplane
configuration and inspection type, range between 1,100 flight cycles
and 18,000 flight cycles.
    Boeing Special Attention Service Bulletin 737-53-1287, dated March
11, 2009, specifies prior or concurrent accomplishment, for certain
airplanes, of the replacement of bonded skin panels with solid skin
panels in accordance with Part 5 of Boeing Service Bulletin 737-
53A1042, Revision 5, dated October 5, 1984. The actions specified in
Boeing Service Bulletin 737-53A1042, Revision 5, dated October 5, 1984,
are necessary to comply with AD 90-06-02, Amendment 39-6489 (55 FR
8372, March 7, 1990).

FAA's Determination and Requirements of This Proposed AD

    We are proposing this AD because we evaluated all relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of these same type
designs. This proposed AD would require accomplishing the actions
specified in the service information described previously, except as
discussed under ``Difference Between the Proposed AD and Service
Bulletin.''

Difference Between the Proposed AD and Service Bulletin

    Boeing Special Attention Service Bulletin 737-53-1287, dated March
11, 2009, 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:
     Using 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) that has been
authorized by the Manager, Seattle ACO, to make those findings.

Interim Action

    We consider this proposed AD interim action. If final action is
later identified, we might consider further rulemaking then.

Costs of Compliance

    We estimate that this proposed AD would affect 1,016 airplanes of
U.S. registry. The following table provides the estimated costs for
U.S. operators to comply with this proposed AD.

                                                                 Table--Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                     Number of
                                                                   Average                                             U.S.-
                Action                        Work hours          labor rate     Parts         Cost per product      registered         Fleet cost
                                                                   per hour                                          airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Inspection...........................  Between 3 and 9.........          $85         None  Between $255 and $765,           629  Between $160,395 and
                                                                                            per inspection cycle.                 $481,185, per
                                                                                                                                  inspection cycle.
Concurrent Replacement for Group 2     2,112...................          $85      $35,000  $214,520...............          387  $83,019,240.
 airplanes.\1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The concurrent modification for Group 2 airplanes required by this AD is already required by AD 90-06-02. AD 90-06-02 mandated the skin replacement
  per Boeing Service Bulletin 737-53A1042 within 20 years of the manufacture date of the airplane. All group 2 airplanes have exceeded the 20-year
  threshold.

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), 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.
    You can find our regulatory evaluation and the estimated costs of
compliance in the AD Docket.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.

[[Page 19566]]

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

    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]

    2. The FAA amends Sec.  39.13 by adding the following new AD:

The Boeing Company: Docket No. FAA-2010-0036; Directorate Identifier
2009-NM-077-AD.

Comments Due Date

    (a) We must receive comments by June 1, 2010.

Affected ADs

    (b) AD 90-06-02, Amendment 39-6489, affects this AD.

Applicability

    (c) 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 Special Attention Service Bulletin 737-53-
1287, dated March 11, 2009.

Subject

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

Unsafe Condition

    (e) This AD results from reports of cracks of the skin and
surrounding structure under the number 3 very high frequency (VHF)
antenna on the lower external surface of the airplane at Buttock
Line 0.0, aft of the main landing gear wheel well. The Federal
Aviation Administration is issuing this AD to detect and correct
cracks and corrosion of the skin and surrounding structure under the
number 3 VHF antenna, which could result in separation of the
antenna from the airplane, and rapid depressurization of the
airplane.

Compliance

    (f) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.

Inspections

    (g) Except as required by paragraphs (m) and (n) of this AD, at
the applicable time in paragraph 1.E., ``Compliance,'' of Boeing
Special Attention Service Bulletin 737-53-1287, dated March 11,
2009: Do external detailed and high frequency eddy current (HFEC)
inspections for cracking in the skin, and for cracking and corrosion
in the skin, as applicable; and an internal detailed inspection for
cracking or corrosion in the skin, antenna support structure, and
surrounding frames and stringers, under the number 3 VHF antenna, as
applicable; in accordance with the Accomplishment Instructions of
Boeing Special Attention Service Bulletin 737-53-1287, dated March
11, 2009, except as provided by paragraph (h) of this AD. Repeat the
inspections, as applicable, thereafter at the applicable time
specified in paragraph 1.E., ``Compliance,'' of Boeing Special
Attention Service Bulletin 737-53-1287, dated March 11, 2009 except
as provided by paragraph (i) of this AD.
    (h) For airplanes on which any external detailed, or external
detailed and HFEC inspection is done, and an external doubler exists
under the cover plate that extends a minimum of 3 rows of fasteners
all around the cover plate: Do the applicable inspections on the
doubler instead of the skin.
    (i) For Group 1-4, configuration 2 airplanes having a cover
plate at the number 3 VHF antenna location: Accomplishing the HFEC
inspection terminates the repetitive external detailed inspections.

Corrective Actions

    (j) If any cracking or corrosion is found during any inspection
required by this AD, before further flight, repair the crack or
corrosion using a method approved in accordance with the procedures
specified in paragraph (o) of this AD.

Concurrent Requirement

    (k) For Group 2 airplanes, as identified in Boeing Special
Attention Service Bulletin 737-53-1287, dated March 11, 2009: Before
or concurrently with accomplishing the requirements of paragraph (g)
of this AD, replace the bonded skin panels with solid skin panels,
in accordance with the Accomplishment Instructions of Boeing Service
Bulletin 737-53A1042, Revision 9, dated July 25, 1991.

    Note 1: The concurrent requirement for replacement of bonded
skin panels with solid skin panels is already required by AD 90-06-
02, Amendment 39-6489.

Replacements Accomplished According to Previous Issue of Service
Bulletin

    (l) Replacements accomplished before the effective date of this
AD in accordance with the Accomplishment Instructions of the service
bulletins specified in Table 1 of this AD are considered acceptable
for compliance with the corresponding action specified in paragraph
(k) of this AD.

               Table 1--Previously Issued Service Bulletin
------------------------------------------------------------------------
             Document               Revision             Date
------------------------------------------------------------------------
Boeing Service Bulletin 737-               5  October 5, 1984.
 53A1042.
Boeing Service Bulletin 737-               6  August 10, 1989.
 53A1042.
Boeing Service Bulletin 737-               7  October 19, 1989.
 53A1042.
Boeing Service Bulletin 737-               8  July 19, 1990.
 53A1042.
------------------------------------------------------------------------

Exceptions to Service Bulletin

    (m) Where Boeing Special Attention Service Bulletin 737-53-1287,
dated March 11, 2009, specifies a compliance time after the date on
that service bulletin, this AD requires compliance after the
effective date of this AD.
    (n) The Compliance Time column of Table 5 of paragraph 1.E.,
``Compliance,'' of Boeing Special Attention Service Bulletin 737-53-
1287, dated March 11, 2009, is missing the phrase ``(Whichever
Occurs Later).'' Compliance with the actions in the Action column of
Table 5 of paragraph 1.E., ``Compliance,'' of Boeing Special
Attention Service Bulletin 737-53-1287, dated March 11, 2009, is
required by the later of the corresponding times specified in the
Compliance Time column of Table 5 of paragraph 1.E., ``Compliance,''
of Boeing Special Attention Service Bulletin 737-53-1287, dated
March 11, 2009.

Alternative Methods of Compliance (AMOCs)

    (o)(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. Send information to
ATTN: Wayne Lockett, Aerospace Engineer, Airframe Branch, ANM-120S,
FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW.,
Renton, Washington 98057-3356; telephone (425) 917-6447; fax (425)
917-6590. Or, e-mail information to 9-ANM-Seattle-ACO-AMOC-
Requests@faa.gov.
    (2) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Before using any approved AMOC on any airplane to which the AMOC
applies, notify your principal maintenance inspector (PMI) or
principal avionics inspector (PAI), as appropriate, or lacking a
principal inspector, your local Flight Standards District Office.
The AMOC approval letter must specifically reference this AD.
    (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.


[[Page 19567]]


    Issued in Renton, Washington on April 2, 2010.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2010-8570 Filed 4-14-10; 8:45 am]
BILLING CODE 4910-13-P

