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[Federal Register Volume 77, Number 52 (Friday, March 16, 2012)]
[Proposed Rules]
[Pages 15640-15644]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-6470]

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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 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of 
comment period.

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SUMMARY: We are revising an earlier proposed airworthiness directive 
(AD) for certain The Boeing Company Model 737-200, -200C, -300, -400, 
and -500 series airplanes. That NPRM proposed to require inspections 
for cracking and corrosion under the number 3 very high frequency (VHF) 
antenna, and corrective actions if necessary; and, for certain 
airplanes, replacing bonded skin panels with solid skin panels if not 
previously accomplished. That NPRM was prompted by 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. This action revises that NPRM by 
adding an optional preventive

[[Page 15641]]

modification, which would terminate the inspection requirements for 
certain airplanes; changing certain repairs; and adding inspections. We 
are proposing this supplemental NPRM 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. Since these 
actions impose an additional burden over that proposed in the original 
NPRM, we are reopening the comment period to allow the public the 
chance to comment on these proposed changes.

DATES: We must receive comments on this supplemental NPRM by April 30, 
2012.

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 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; email 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 (phone: 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; phone: (425) 917-
6447; fax: (425) 917-6590; email: wayne.lockett@faa.gov.

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 issued an NPRM to amend 14 CFR part 39 to include an 
airworthiness directive (AD) that would apply to certain The Boeing 
Company Model 737-200, -200C, -300, -400, and -500 series airplanes. 
That original NPRM was published in the Federal Register on April 15, 
2010 (75 FR 19564). That original NPRM proposed to require repetitive 
inspections for cracking and corrosion of the skin and surrounding 
structure under the number 3 VHF antenna, and corrective actions if 
necessary. Also, for certain airplanes, that original NPRM proposed to 
require replacing bonded skin panels with solid skin panels if not 
previously accomplished.

Actions Since Previous NPRM (75 FR 19564, April 15, 2010) Was Issued

    The original NPRM (75 FR 19564, April 15, 2010) referred to Boeing 
Special Attention Service Bulletin 737-53-1287, dated March 11, 2009. 
Since we issued the original NPRM, we have reviewed Boeing Special 
Attention Service Bulletin 737-53-1287, Revision 1, dated November 15, 
2010. Among other things, this service bulletin provides the following 
changes:
     Adds an optional preventive modification for certain 
airplane groups, which would eliminate the need for the repetitive 
inspections of those airplanes. The modification involves various high 
frequency eddy current (HFEC) and detailed inspections for cracking and 
corrosion of the skin, support channel, holes, and support structure in 
the area of the number 3 VHF antenna; and repair if necessary, or 
replacing a cracked or corroded support channel with a new or 
serviceable support channel, if necessary. The modification also 
entails installing antenna support structure.
     Reassigns certain airplanes to different groups.
     Gives instructions for doing repairs if a crack is found, 
for certain airplane groups and certain conditions.
     Adds HFEC inspections (that are done along with previously 
specified internal detailed inspections) with the antenna removed.
     Adds Group 7 airplanes (line numbers 1-291) and specifies 
that, for these airplanes, operators must contact Boeing for 
inspection, repair, and preventive modification instructions. These 
airplanes are subject to a prior or concurrent action of replacing 
bonded skin panels with solid skin panels, as specified in Part V of 
Boeing Service Bulletin 737-53A1042, Revision 9, dated July 25, 1991. 
(The actions specified in that service bulletin are already required by 
AD 90-06-02, Amendment 39-6489 (55 FR 8372, March 7, 1990)).

Comments

    We gave the public the opportunity to comment on the original NPRM 
(75 FR 19564, April 15, 2010). The following presents the comment 
received on the NPRM and the FAA's response to the comment.

Request To Change Requirements for Certain Airplanes

    Boeing submitted a comment related to the service information. 
However, the substance of the comment is addressed in Boeing Special 
Attention Service Bulletin 737-53-1287, Revision 1, dated November 15, 
2010 as discussed above in ``Actions Since Previous NPRM (75 FR 19564, 
April 15, 2010) Was Issued.''

FAA's Determination

    We are proposing this supplemental NPRM 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. Certain changes described above expand the scope of 
the original

[[Page 15642]]

NPRM (75 FR 19564, April 15, 2010). As a result, we have determined 
that it is necessary to reopen the comment period to provide additional 
opportunity for the public to comment on this supplemental NPRM.

Proposed Requirements of the Supplemental NPRM

    This supplemental NPRM would require accomplishing the actions 
specified in the revised service information described previously, 
except as discussed under ``Differences Between the Supplemental NPRM 
and the Service Information.''

Differences Between the Supplemental NPRM and the Service Information

    Where paragraph 1.A., ``Effectivity,'' of Boeing Special Attention 
Service Bulletin 737-53-1287, Revision 1, dated November 15, 2010, 
places Model 737-200 and -200C airplanes having line numbers 1-291 into 
group 7, for purposes of this supplemental NPRM, these airplanes would 
be subject to the proposed requirements for Group 2, Configuration 1, 
2, or 3, as applicable. There are no configuration differences for 
airplanes having line numbers 1-291 from the Group 2 airplanes.
    Table 10 in paragraph 1.E., ``Compliance,'' of Boeing Special 
Attention Service Bulletin 737-53-1287, Revision 1, dated November 15, 
2010; and Part 8 of the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 737-53-1287, Revision 1, dated November 15, 
2010; specify post-repair/modification inspections at the number 3 VHF 
antenna location, which may be used in support of compliance with 
section 121.1109(c)(2) or 129.109(c)(2) of the Federal Aviation 
Regulations (14 CFR 121.1109(c)(2) or 129.109(c)(2)), but this 
supplemental NPRM does not propose to require those post-repair/
modification inspections. This difference has been coordinated with 
Boeing.

Costs of Compliance

    We estimate that this proposed AD will affect 629 airplanes of U.S. 
registry.
    We estimate the following costs to comply with this proposed AD:

                                                                     Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                  Number of U.S.-
               Action                        Labor cost               Parts cost             Cost per product        registered   Cost on U.S. operators
                                                                                                                     airplanes
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Inspection..........................  Up to 13 work-hours x    None....................  Up to $1,105 per                    629  Up to $695,045 per
                                       $85 per hour = Up to                               inspection cycle.                        inspection cycle.
                                       $1,105 per inspection
                                       cycle.
Concurrent Replacement for Group 2    2,112 work-hours x $85   $35,000.................  $214,520...............             387  $83,019,240.
 and Group 7 airplanes \1\.            per hour = $179,520.
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\1\ The concurrent modification for Group 2 and Group 7 airplanes required by this proposed AD is already required by AD 90-06-02, Amendment 39-6489 (55
  FR 8372, March 7, 1990). AD 90-06-02 mandated the skin replacement within 20 years of the manufacture date of the airplane. All Group 2 and Group 7
  airplanes have exceeded the 20-year threshold.

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

    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 
airworthiness directive (AD):

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

(a) Comments Due Date

    We must receive comments by April 30, 2012.

[[Page 15643]]

(b) Affected ADs

    AD 90-06-02, Amendment 39-6489 (55 FR 8372, March 7, 1990), 
affects this AD.

(c) Applicability

    This AD applies to The Boeing Company Model 737-200, -200C, -
300, -400, -500 series airplanes, certificated in any category, as 
identified in Boeing Special Attention Service Bulletin 737-53-1287, 
Revision 1, dated November 15, 2010.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 53: Fuselage.

(e) Unsafe Condition

    This AD was prompted by 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. We are 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.

(f) Compliance

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

(g) Inspections

    Except as required by paragraph (i)(1) of this AD, at the 
applicable times specified in tables 1 through 9, paragraph 1.E., 
``Compliance,'' of Boeing Special Attention Service Bulletin 737-53-
1287, Revision 1, dated November 15, 2010: Do the applicable 
inspections (external detailed and high frequency eddy current 
(HFEC), external detailed, external HFEC, or internal detailed and 
HFEC) for cracks or corrosion in the skin, support, frames, 
stringers, or antenna, as applicable. Do the inspections in 
accordance with Parts 1, 3, 4, and 5 of the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 737-53-
1287, Revision 1, dated November 15, 2010, except as required by 
paragraphs (i)(2) and (i)(3) of this AD. Repeat the applicable 
inspections thereafter at the applicable times specified in tables 1 
through 9, paragraph 1.E., ``Compliance,'' of Boeing Special 
Attention Service Bulletin 737-53-1287, Revision 1, dated November 
15, 2010, until the actions required by paragraph (j) of this AD are 
done.

(h) Repair

    (1) If any crack or corrosion is found during any inspection 
required by paragraph (g) of this AD: Repair before further flight, 
in accordance with the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 737-53-1287, Revision 1, dated November 
15, 2010, except as required by paragraphs (i)(2) and (i)(3) of this 
AD. Repair of any crack or corrosion terminates the repetitive 
inspection requirements of paragraph (g) of this AD for the repaired 
area only.
    (2) Operators must obtain an approved damage tolerance 
evaluation for any repair installed to comply with Section 
121.1109(c)(2) or 129.109(c)(2) of the Code of Federal Regulations 
(14 CFR 121.1109(c)(2) or 129.109(c)(2)).
    Note 1 to paragraph (h)(2) of this AD: Additional guidance on 
damage tolerance evaluation for repairs can be found in table 10 in 
paragraph 1.E., ``Compliance,'' of Boeing Special Attention Service 
Bulletin 737-53-1287, Revision 1, dated November 15, 2010; and Part 
8 of the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 737-53-1287, Revision 1, dated November 15, 2010.

(i) Exceptions

    (1) Where Boeing Special Attention Service Bulletin 737-53-1287, 
Revision 1, dated November 15, 2010, 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.
    (2) Where Boeing Special Attention Service Bulletin 737-53-1287, 
Revision 1, dated November 15, 2010, specifies contacting Boeing for 
inspection or repair instructions: Do the applicable action using a 
method approved in accordance with the procedures specified in 
paragraph (m) of this AD.
    (3) For Group 7 airplanes, as identified in paragraph 1.A., 
``Effectivity,'' of Boeing Special Attention Service Bulletin 737-
53-1287, Revision 1, dated November 15, 2010: Use the applicable 
instructions for Group 2, Configuration 1, 2, or 3, as identified in 
Boeing Special Attention Service Bulletin 737-53-1287, Revision 1, 
dated November 15, 2010.

(j) Optional Terminating Action

    For Groups 1, 2, 3, 4, 6, and 7 airplanes, as identified in 
Boeing Special Attention Service Bulletin 737-53-1287, Revision 1, 
dated November 15, 2010: Except as provided by paragraphs (i)(2) and 
(i)(3) of this AD, accomplishment of the preventive modification, 
including all applicable HFEC and detailed inspections for cracking 
or corrosion inside or outside the repair skin cutout area, in the 
frame fastener holes, or in the support channel; and all applicable 
repairs or replacements; as specified in the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 737-53-
1287, Revision 1, dated November 15, 2010: Terminates the repetitive 
inspection requirements of paragraph (g) of this AD.

(k) Concurrent Skin Panel Replacement

    For Groups 2 and 7 airplanes, as identified in Boeing Special 
Attention Service Bulletin 737-53-1287, Revision 1, dated November 
15, 2010: Before or concurrently with accomplishing the requirements 
of paragraph (g) of this AD, do the replacement of 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; except as required by paragraph (i)(3) of this 
AD. The actions specified in paragraph (k) of this AD are also 
required by AD 90-06-02, Amendment 39-6489 (55 FR 8372, March 7, 
1990).

(l) Credit for Previous Actions

    (1) This paragraph gives credit for the replacement required by 
paragraph (k) of this AD, if the replacement of bonded skin panels 
with solid skin panels was accomplished before the effective date of 
this AD using the Accomplishment Instructions of the service 
information identified in paragraphs (l)(1)(i), (l)(1)(ii), 
(l)(1)(iii), and (l)(1)(iv) of this AD:
    (i) Boeing Service Bulletin 737-53A1042 Revision 5, dated 
October 5, 1984.
    (ii) Boeing Service Bulletin 737-53A1042 Revision 6, dated 
August 10, 1989.
    (iii) Boeing Service Bulletin 737-53A1042 Revision 7, dated 
October 19, 1989.
    (iv) Boeing Service Bulletin 737-53A1042 Revision 8, dated July 
19, 1990.
    (2) This paragraph gives credit for the inspections required by 
paragraph (g) of this AD, if the inspections were accomplished 
before the effective date of this AD using the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 737-53-
1287, dated March 11, 2009.

(m) 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 the Related Information 
section of this AD. Information may be emailed to 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (2) Before using any approved AMOC, notify your Principal 
Maintenance Inspector or Principal Avionics Inspector, as 
appropriate, or lacking a principal inspector, your local Flight 
Standards 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.

(n) Related Information

    (1) For more information about this AD, contact Wayne Lockett, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO, 
1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: 425-917-
6447; fax: 425-917-6590; email: wayne.lockett@faa.gov.
    (2) For service information identified in this 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; email 
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

[[Page 15644]]

availability of this material at the FAA, call 425-227-1221.

    Issued in Renton, Washington, on March 1, 2012.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-6470 Filed 3-15-12; 8:45 am]
BILLING CODE 4910-13-P
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