[Federal Register: March 18, 2010 (Volume 75, Number 52)]
[Proposed Rules]
[Page 13046-13049]
[DOCID:fr18mr10-21]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0232; Directorate Identifier 2009-NM-032-AD]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Model 747-200C, -
200F, -400, -400D, and -400F Series Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede an existing airworthiness
directive (AD) that applies to certain Model 747-200C, -200F, -400, -
400D, and -400F series airplanes. The existing AD currently requires
repetitive inspections for cracks in the overlapping (upper) skin,
upper fastener row of the lap joints of the fuselage skin in sections
41, 42, and 46; and related investigative and corrective actions, if
necessary. This proposed AD would expand the inspection area in the
existing AD, and add a modification of certain lap joints and certain
post-repair inspections of the lap joints. Accomplishing the
modification would end the repetitive inspections required by the
existing AD for the length of lap joint that is modified. This proposed
AD results from a structural review of affected skin lap joints for
widespread fatigue damage. We are proposing this AD to prevent fatigue
cracking in certain lap joints, which could result in rapid
depressurization of the airplane.

DATES: We must receive comments on this proposed AD by May 3, 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:<PHONE_NUMBER>.
     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<PHONE_NUMBER>,
extension 1; fax<PHONE_NUMBER>; e-mail<EMAIL_ADDRESS>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<PHONE_NUMBER>.

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<PHONE_NUMBER>) is in the
ADDRESSES section. Comments will be available in the AD docket shortly
after receipt.

FOR FURTHER INFORMATION CONTACT: Ivan Li, Aerospace Engineer, Airframe
Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind
Avenue, SW., Renton, Washington 98057-3356; telephone<PHONE_NUMBER>;
fax<PHONE_NUMBER>.

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-2010-0232;
Directorate Identifier 2009-NM-032-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

    On February 27, 2006, we issued AD 2006-05-09, amendment 39-14506
(71 FR 12122, March 9, 2006), for certain Model 747-200C, -200F, -400,
-400D, and -400F series airplanes. That AD requires repetitive
inspections for cracks in the overlapping (upper) skin, upper fastener
row of the lap joints of the fuselage skin in sections 41, 42, and 46;
and related investigative and corrective actions, if necessary. That AD
resulted from fatigue tests and an analysis that identified areas of
the fuselage lap joints where fatigue cracks can occur. We issued that
AD to detect and correct fatigue cracks in the overlapping (upper)
skin, upper fastener row of the lap joints of the fuselage skin in
sections 41, 42, and 46, which could adversely affect the structural
integrity of the airplane.

Actions Since Existing AD Was Issued

    Since we issued AD 2006-05-09, the manufacturer has conducted a
structural review of affected skin lap joints for widespread fatigue
damage, and has identified additional necessary inspection and
modification actions. It is recommended that all lap joints with an
upper skin thickness of 0.09 inch or less should be inspected;
therefore, the inspection area has been expanded to include a new Area
2 (i.e., the lap joint at STA 450, S-0 to S1L and the S-4L lap joint
between STA 1970 and STA 2000). It is also recommended that lap joints
in sections 41 and 42 with an upper skin thickness of 0.071 inch or
less should be modified; and post-repair inspections have been
identified.

Revised Service Information

    We have reviewed Boeing Alert Service Bulletin 747-53A2499,
Revision 1, dated October 30, 2008. That service bulletin describes
procedures for repetitive external surface high frequency eddy current
(HFEC), external low frequency eddy current (LFEC), and internal LFEC
inspections for cracks in the overlapping (upper) skin, upper fastener
row of the lap joints of the fuselage skin in sections 41, 42, and 46;
and related investigative and corrective actions, if necessary.
    For airplanes on which any crack is found, the related
investigative actions include open-hole HFEC inspections of the
fastener holes to find further cracking. The corrective actions include
repairing any cracked lap joint and an open-hole HFEC inspection of the
skin at all existing fastener locations common to the repair. The
corrective actions also include repairing any crack found during
accomplishment of the inspections.
    That service bulletin also describes a modification of the lap
joints in sections 41 and 42. The modification includes fabricating and
installing skin doublers on affected lap joints.
    The compliance time for accomplishing the new Area 2 inspections is
before the accumulation of 22,000 total flight cycles, or within 3,000
flight cycles after the last HFEC inspection of that area, as specified
in the Boeing Model 747 Supplemental Structural Inspection Document, or
within 1,000 flight cycles from the date on Revision 1 of the service
bulletin; whichever occurs latest.
    For areas on which a lap joint repair was installed and the repair
doubler is greater than or equal to 40 inches long, that service
bulletin describes procedures for repetitive internal surface HFEC
inspections of certain doublers of the lap joints for cracks. The
compliance time for accomplishing the inspections is within 15,000
flight cycles after the repair was installed.
    That service bulletin specifies repeating the applicable inspection
every 3,000 flight cycles, or every 1,500 flight cycles for airplanes
that have accumulated 30,000 total flight cycles or more.
    The compliance time for accomplishing the new lap joint
modification is before the accumulation of 30,000 total flight cycles,
or within 3,000 flight cycles from the date of Revision 1 of the
service bulletin, whichever is later. Accomplishing this modification
eliminates the need for the repetitive inspections for the length of
lap joint that is modified.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an
unsafe condition that is likely to develop on other airplanes of the
same type design. For this reason, we are proposing this AD, which
would supersede AD 2006-05-09 and would retain the requirements of the
existing AD. This proposed AD would also require accomplishing the
actions specified in the service information described previously.

Explanation of Change Made to This Proposed AD

    Boeing Commercial Airplanes has received an Organization
Designation Authorization (ODA), which replaces the previous
designation as a Delegation Option Authorization (DOA) holder. We have
revised paragraph (n)(3) of this proposed AD to add delegation of
authority to Boeing Commercial Airplanes ODA to approve an alternative
method of compliance for any repair required by this AD.

Change to Existing AD

    This proposed AD would retain all requirements of AD 2006-05-09.
Since AD 2006-05-09 was issued, we have

added a new paragraph to include the ATA code. As a result, the
corresponding paragraph identifiers have changed in this proposed AD,
as listed in the following table:

                      Revised Paragraph Identifiers
------------------------------------------------------------------------
                                      Corresponding requirement in this
    Requirement in AD 2006-05-09                 proposed AD
------------------------------------------------------------------------
             paragraph (f)                        paragraph (g)
             paragraph (g)                        paragraph (h)
             paragraph (h)                        paragraph (l)
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Costs of Compliance

    There are about 735 airplanes of the affected design in the
worldwide fleet. This proposed AD would affect about 96 airplanes of
U.S. registry.
    The actions that are required by AD 2006-05-09 and retained in this
proposed AD take about 541 work hours per airplane, at an average labor
rate of $85 per work hour. Based on these figures, the estimated cost
of the currently required actions is $45,985 per airplane, per
inspection cycle.
    The new proposed Area 2 inspections would take about 124 work hours
per airplane, at an average labor rate of $85 per work hour. Based on
these figures, the estimated cost of the new inspections specified in
this proposed AD for U.S. operators is $1,011,880, or $10,540 per
airplane, per inspection cycle.
    The new proposed modification would take about 4,799 work hours per
airplane, at an average labor rate of $85 per work hour. Required parts
costs per airplane would be minimal. Based on these figures, the
estimated cost of the new actions specified in this proposed AD for
U.S. operators is $39,159,840, or $407,915 per airplane.

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 have 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 that the 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.
    We prepared a regulatory evaluation of the estimated costs to
comply with this proposed AD and placed it in the AD docket. See the
ADDRESSES section for a location to examine the regulatory evaluation.

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 removing amendment 39-14506 (71 FR
12122, March 9, 2006) and adding the following new AD:

The Boeing Company: Docket No. FAA-2010-0232; Directorate Identifier
2009-NM-032-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by May 3,
2010.

Affected ADs

    (b) This AD supersedes AD 2006-05-09.

Applicability

    (c) This AD applies to The Boeing Company Model 747-200C, -200F,
-400, -400D, and -400F series airplanes, certificated in any
category; as identified in Boeing Alert Service Bulletin 747-
53A2499, Revision 1, dated October 30, 2008.

Subject

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

Unsafe Condition

    (e) This AD results from a structural review of affected skin
lap joints for widespread fatigue damage. The Federal Aviation
Administration is issuing this AD to prevent fatigue cracking in
certain lap joints, which could result in 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.

Restatement of Requirements of AD 2006-05-09, With Revised Service
Information

Initial Inspections and Related Investigative and Corrective Actions

    (g) For airplanes identified in Boeing Alert Service Bulletin
747-53A2499, dated August 11, 2005: At the applicable time specified
in Table 1 of this AD, do an external surface high frequency eddy
current (HFEC), external low frequency eddy current (LFEC), and
internal LFEC inspection, as applicable, for cracks in the
overlapping (upper) skin, upper fastener row of the lap joints of
the fuselage skin in sections 41, 42, and 46, and any applicable
related investigative and corrective actions by doing all of the
actions in accordance with the Accomplishment Instructions of Boeing
Alert Service Bulletin 747-53A2499, dated August 11, 2005; or
Revision 1, dated October 30, 2008. Do any applicable related
investigative and corrective actions before further flight. As of
the effective date of this AD, only Revision 1, dated October 30,
2008, of Boeing Alert Service Bulletin 747-53A2499 may be used.

                    Table 1--Initial Compliance Time
------------------------------------------------------------------------
    For airplanes on which
 Structural Significant Items
 (SSIs) F-25G, F-25H, and F-                   Inspect--
            25I--
------------------------------------------------------------------------
(1) Have not been inspected    Before the accumulation of 22,000 total
 in accordance with paragraph   flight cycles, or within 1,000 flight
 (i) of AD 2004-07-22 R1,       cycles after April 13, 2006 (the
 amendment 39-15326, using      effective date of AD 2006-05-09),
 the HFEC method.               whichever occurs later.
(2) Have been inspected in     Within 3,000 flight cycles after the most
 accordance with paragraph      recent supplemental structural
 (i) of AD 2004-07-22 R1,       inspection document (SSID) inspection of
 using the HFEC method.         each applicable structural significant
                                item (as given in Boeing Document D6-
                                35022, ``SSID for Model 747 Airplanes,''
                                Revision G, dated December 2000), or
                                within 1,000 flight cycles after April
                                13, 2006, whichever occurs later.
------------------------------------------------------------------------

Repetitive Inspections

    (h) Repeat the applicable inspections required by paragraph (g)
of this AD thereafter at intervals not to exceed those specified in
paragraph 1.E., ``Compliance,'' (including the note) of Boeing Alert
Service Bulletin 747-53A2499, dated August 11, 2005; or Revision 1,
dated October 30, 2008. As of the effective date of this AD, only
Revision 1, dated October 30, 2008, of Boeing Alert Service Bulletin
747-53A2499 may be used.

New Requirements of This AD

Repetitive Inspections/Investigative and Corrective Actions

    (i) For all airplanes: Do an external HFEC inspection of the lap
joints in Sections 41, 42, and 46 for cracks, by doing all the
actions, including all applicable related investigative and
corrective actions, specified in the Accomplishment Instructions of
Boeing Alert Service Bulletin 747-53A2499, Revision 1, dated October
30, 2008. Do the inspection at the applicable time specified in
paragraph 1.E. of Boeing Alert Service Bulletin 747-53A2499,
Revision 1, dated October 30, 2008; except as required by paragraph
(m) of this AD. Do all applicable related investigative and
corrective actions before further flight. Repeat the inspection
thereafter at the times specified in paragraph 1.E. of Boeing Alert
Service Bulletin 747-53A2499, Revision 1, dated October 30, 2008.
Accomplishment of the inspections required by this paragraph
terminates the inspections required by paragraphs (g) and (h) of
this AD.
    (j) For areas on which a lap joint repair was installed and the
repair doubler is greater than or equal to 40 inches long: Do
initial and repetitive internal HFEC inspections for cracks by doing
all the actions, including all applicable corrective actions,
specified in the Accomplishment Instructions of Boeing Alert Service
Bulletin 747-53A2499, Revision 1, dated October 30, 2008, except as
required by paragraph (l) of this AD. Do the inspections and
corrective actions at the times specified in paragraph 1.E. of
Boeing Alert Service Bulletin 747-53A2499, Revision 1, dated October
30, 2008, except as required by paragraph (m) of this AD.

Terminating Action

    (k) Modify the applicable lap joints in sections 41 and 42 by
doing all the applicable actions specified in the Accomplishment
Instructions of Boeing Alert Service Bulletin 747-53A2499, Revision
1, dated October 30, 2008, at the time specified in paragraph 1.E.
of Boeing Alert Service Bulletin 747-53A2499, Revision 1, dated
October 30, 2008; except as required by paragraphs (l) and (m) of
this AD. Accomplishing this modification terminates the repetitive
inspections of the skin lap joints in sections 41 and 42 required by
paragraphs (i) and (j) of this AD for the length of lap joint that
is modified.

Exceptions to Service Bulletin Procedures

    (l) Where Boeing Alert Service Bulletin 747-53A2499, Revision 1,
dated October 30, 2008, specifies to contact Boeing for appropriate
action, before further flight, repair the crack using a method
approved in accordance with the procedures specified in paragraph
(n) of this AD.
    (m) Where Boeing Alert Service Bulletin 747-53A2499, Revision 1,
dated October 30, 2008, specifies a compliance time after the date
of the service bulletin, this AD requires compliance within the
specified compliance time after the effective date of this AD.

Alternative Methods of Compliance (AMOCs)

    (n)(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 Ivan
Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone
(425) 917-6437; fax<PHONE_NUMBER>. Information may be e-mailed to:
<EMAIL_ADDRESS>    (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) or other person 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.
    (4) AMOCS approved previously in accordance with AD 2006-05-09
are approved as alternative methods of compliance with the
corresponding requirements of this AD.

    Issued in Renton, Washington, on March 10, 2010.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2010-5940 Filed 3-17-10; 8:45 am]
BILLING CODE 4910-13-P