
[Federal Register: October 7, 2010 (Volume 75, Number 194)]
[Rules and Regulations]               
[Page 61977-61980]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07oc10-2]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0552; Directorate Identifier 2009-NM-095-AD; 
Amendment 39-16464; AD 2010-21-04]
RIN 2120-AA64

 
Airworthiness Directives; The Boeing Company Model 747-100, 747-
200B, and 747-200F Series Airplanes

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

ACTION: Final rule.

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SUMMARY: The FAA is superseding two existing airworthiness directives 
(ADs), which apply to certain Model 747-100, 747-200B, and 747-200F 
series airplanes. The existing ADs currently require inspections to 
detect fatigue-related skin cracks and corrosion of the skin panel lap 
joints in the fuselage upper lobe, and repair if necessary. One of the 
existing ADs, AD 94-12-09, also requires modification of certain lap 
joints and inspection of modified lap joints. The other AD, AD 90-15-
06, requires repetitive detailed external visual inspections of the 
fuselage skin at the upper lobe skin lap joints for cracks and evidence 
of corrosion, and related investigative and corrective actions. This AD 
reduces the maximum interval of the post-modification inspections, and 
adds post-repair inspection requirements for certain airplanes. This AD 
results from reports of cracking on modified airplanes. We are issuing 
this AD to detect and correct fatigue cracking and corrosion in the 
fuselage upper lobe skin lap joints, which could lead to rapid 
decompression of the airplane and inability of the structure to carry 
fail-safe loads.

DATES: This AD becomes effective November 12, 2010.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of November 12, 
2010.

ADDRESSES: 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; e-mail me.boecom@boeing.com; 
Internet https://www.myboeingfleet.com.

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 AD, the regulatory evaluation, 
any comments received, and other information. The address for the 
Docket Office (telephone 800-647-5527) is the Document Management 
Facility, U.S. Department of Transportation, Docket Operations, M-30, 
West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., 
Washington, DC 20590.

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 (425) 917-6437; 
fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to include an AD that supersedes AD 90-15-06, Amendment 39-
6653 (55 FR 28600, July 12, 1990), and AD 94-12-09, Amendment 39-8937 
(59 FR 30285, June 13, 1994). The existing ADs apply to certain Model 
747-100, 747-200B, and 747-200F series airplanes. That NPRM was 
published in the Federal Register on June 22, 2010 (75 FR 35356). That 
NPRM proposed to continue to require inspections to detect fatigue-
related skin cracks and corrosion of the skin panel lap joints in the 
fuselage upper lobe, and repair if necessary; modification of certain 
lap joints and inspection of modified lap joints; and repetitive 
detailed external visual inspections of the fuselage skin at the upper 
lobe skin lap joints for cracks and evidence of corrosion, and related 
investigative and corrective actions. That NPRM also proposed to reduce 
the maximum interval of the post-modification inspections, and adds 
post-repair inspection requirements for certain airplanes.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comment that has been 
received on the NPRM.

Request to Correct Typographical Error in Paragraph (l) of the NPRM

    Boeing requests that we revise paragraph (l) of the NPRM to change 
the numeral ``1'' to the letter ``l'' to correctly identify the 
paragraph references.
    We agree and have corrected the typographical error accordingly.

[[Page 61978]]

Conclusion

    We have carefully reviewed the available data, including the 
comment that has been received, and determined that air safety and the 
public interest require adopting the AD with the change described 
previously. We have determined that this change will neither increase 
the economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    There are about 23 airplanes of the affected design in the 
worldwide fleet. The following table provides the estimated costs for 
U.S. operators to comply with this AD.

                                                                     Estimated Costs
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                                                                                                              Number of
                                            Work      Average                                                   U.S.-
                 Action                    hours     labor rate    Parts           Cost per airplane          registered            Fleet cost
                                                      per hour                                                airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Inspection (required by AD 94-12-09)...        208          $85         $0  $17,680 per inspection cycle...            7  $123,760 per inspection cycle.
Modification (required by AD 94-12-09).      8,160           85          0  $693,600.......................            7  $4,855,200.
Post-Modification Inspection (required          56           85          0  $4,760 per inspection cycle....            7  $33,320 per inspection cycle.
 by AD 94-12-09).
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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 AD will not have federalism 
implications under Executive Order 13132. This AD will 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 this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866;
    (2) Is not a ``significant rule'' under 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 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.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
removing Amendment 39-6653 (55 FR 28600, July 12, 1990) and Amendment 
39-8937 (59 FR 30285, June 13, 1994) and by adding the following new 
airworthiness directive (AD):

2010-21-04 The Boeing Company: Amendment 39-16464. Docket No. FAA-
2010-0552; Directorate Identifier 2009-NM-095-AD.

Effective Date

    (a) This AD becomes effective November 12, 2010.

Affected ADs

    (b) This AD supersedes AD 90-15-06, Amendment 39-6653; and AD 
94-12-09, Amendment 39-8937.

Applicability

    (c) This AD applies to The Boeing Company Model 747-100, 747-
200B, and 747-200F series airplanes, certificated in any category, 
as identified in Boeing Service Bulletin 747-53-2307, Revision 3, 
dated April 16, 2009.

Subject

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

Unsafe Condition

    (e) This AD results from reports of fatigue cracking on modified 
airplanes. The Federal Aviation Administration is issuing this AD to 
detect and correct fatigue cracking and corrosion in the fuselage 
upper lobe skin panel lap joints, which could lead to the rapid 
decompression of the airplane and the inability of the structure to 
carry fail-safe loads.

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 94-12-09, With Revised Service 
Information

Inspection

    (g) Within 1,000 flight cycles after July 13, 1994 (the 
effective date of AD 94-12-09), and thereafter at the intervals 
specified in paragraphs (g)(1), (g)(2), and (g)(3) of this AD, 
perform inspections at the upper lobe skin panel lap joints in 
accordance with Boeing Service Bulletin 747-53-2307, Revision 2, 
dated October 14, 1993; or Revision 3, dated April 16, 2009. After 
the effective date of this AD, only Revision 3 may be used.
    (1) Perform a detailed external visual inspection to detect 
cracks and evidence of corrosion (bulging skin between fasteners, 
blistered paint, dished fasteners, popped rivet heads, or loose 
fasteners) in accordance with Boeing Service Bulletin 747-53-2307, 
Revision 2, dated October 14, 1993; or Revision 3, dated April 16, 
2009. After the effective date of this AD, only Revision 3 may

[[Page 61979]]

be used. Repeat that inspection thereafter at intervals not to 
exceed 2,000 flight cycles until the modification required by 
paragraph (k) of this AD is accomplished.
    (2) Perform a high frequency eddy current (HFEC) inspection to 
detect cracks in the skin at the upper row of fasteners of the skin 
panel lap joints forward of body station (BS) 1000 in accordance 
with Boeing Service Bulletin 747-53-2307, Revision 2, dated October 
14, 1993; or Revision 3, dated April 16, 2009. After the effective 
date of this AD, only Revision 3 may be used. Repeat that inspection 
thereafter at intervals not to exceed 4,000 flight cycles until the 
modification required by paragraph (k) of this AD is accomplished.
    (3) Perform a HFEC inspection to detect cracks in the skin at 
the upper row of fastener holes of the skin panel lap joints aft of 
BS 1480 to 2360 in accordance with Boeing Service Bulletin 747-53-
2307, Revision 2, dated October 14, 1993; or Revision 3, dated April 
16, 2009. After the effective date of this AD, only Revision 3 may 
be used.
    Repeat that inspection thereafter at intervals not to exceed 
6,000 flight cycles until the modification required by paragraph (k) 
of this AD is accomplished.
    (h) If any crack is found during any inspection required by 
paragraph (g) or (l) of this AD, or if any corrosion is found for 
which material loss exceeds 10 percent of the material thickness, 
accomplish paragraphs (h)(1) and (h)(2) of this AD in accordance 
with Boeing Service Bulletin 747-53-2307, Revision 2, dated October 
14, 1993; or Revision 3, dated April 16, 2009. After the effective 
date of this AD, only Revision 3 may be used.
    (1) Prior to further flight, repair any crack or corrosion 
found, in accordance with Boeing Service Bulletin 747-53-2307, 
Revision 2, dated October 14, 1993; or Revision 3, dated April 16, 
2009. After the effective date of this AD, only Revision 3 may be 
used.
    (2) Within 18 months after accomplishing the repair, accomplish 
the ``full'' modification described in Boeing Service Bulletin 747-
53-2307, Revision 2, dated October 14, 1993; or Revision 3, dated 
April 16, 2009; for the remainder of any skin panel lap joint in 
which a crack is found, or in which corrosion is found that exceeds 
10 percent of the material thickness, in accordance with Boeing 
Service Bulletin 747-53-2307, Revision 2, dated October 14, 1993; or 
Revision 3, dated April 16, 2009. After the effective date of this 
AD, only Revision 3 may be used.
    (i) If no crack is found during any inspection required by 
paragraph (g) of this AD, but corrosion is found for which the 
material loss does not exceed 10 percent of the material thickness: 
Accomplish the actions specified in paragraphs (i)(1) and (i)(2) of 
this AD for the entire affected skin panel lap joint, in accordance 
with Boeing Service Bulletin 747-53-2307, Revision 2, dated October 
14, 1993; or Revision 3, dated April 16, 2009. After the effective 
date of this AD, only Revision 3 may be used.
    (1) Within 500 flight cycles after accomplishing the inspection 
during which the corrosion was found, and thereafter at intervals 
not to exceed 500 flight cycles until the ``full'' modification 
required by paragraph (i)(2) of this AD is accomplished: Perform a 
HFEC inspection to detect cracks of the corroded skin panel lap 
joint, in accordance with Boeing Service Bulletin 747-53-2307, 
Revision 2, dated October 14, 1993; or Revision 3, dated April 16, 
2009. After the effective date of this AD, only Revision 3 may be 
used.
    (2) Within 36 months after accomplishing the inspection during 
which the corrosion was found: Accomplish the ``full'' modification, 
in accordance with Boeing Service Bulletin 747-53-2307, Revision 2, 
dated October 14, 1993; or Revision 3, dated April 16, 2009. After 
the effective date of this AD, only Revision 3 may be used.
    (j) The inspections required by paragraph (g) of this AD shall 
be performed by removing the paint and using an approved chemical 
stripper; or by ensuring that each fastener head is clearly visible.
    (k) Except as provided in paragraph (m) of this AD, prior to the 
accumulation of 20,000 total flight cycles, or within the next 1,000 
flight cycles after July 13, 1994, whichever occurs later: 
Accomplish the modification described in Boeing Service Bulletin 
747-53-2307, Revision 2, dated October 14, 1993; or Revision 3, 
dated April 16, 2009; as a ``full'' modification of the skin panel 
lap joints at the locations specified in paragraphs (k)(1) and 
(k)(2) of this AD, as applicable, in accordance with Boeing Service 
Bulletin 747-53-2307, Revision 2, dated October 14, 1993; or 
Revision 3, dated April 16, 2009. After the effective date of this 
AD, only Revision 3 may be used. Accomplishment of this modification 
terminates the repetitive inspection requirements of paragraph (g) 
of this AD.
    (1) For airplane line numbers 001 through 058, inclusive: Modify 
the skin panel lap joints at Stringer 12 (left and right), station 
520 to 1,000; and Stringer 19 (left and right), station 520 to 740.
    (2) For airplane line numbers 59 through 200, inclusive: Modify 
the skin panel lap joints at Stringer 12 (left and right), station 
740 to 1,000; and Stringer 19 (left and right), station 520 to 740.
    (l) For all airplanes: Perform an external HFEC inspection to 
detect skin cracks of any modified skin panel lap joints at the 
times specified in paragraphs (l)(1), (l)(2), and (l)(3) of this AD, 
as applicable, in accordance with Boeing Service Bulletin 747-53-
2307, Revision 2, dated October 14, 1993; or Revision 3, dated April 
16, 2009. As of the effective date of this AD, only Revision 3 may 
be used. Repeat that inspection thereafter at intervals not to 
exceed 3,000 flight cycles, except as required by paragraph (n) of 
this AD.
    (1) For skin panel lap joints on which the ``full'' modification 
has been accomplished: Within 10,000 flight cycles after 
accomplishment of that modification.
    (2) For skin panel lap joints on which the ``optional'' 
(partial) modification has been accomplished: Within 7,000 flight 
cycles after accomplishment of that modification.
    (3) For skin panel lap joints having deep countersink fasteners 
located at Section 42 on which the ``full'' modification, as 
described in Boeing Service Bulletin 747-53-2307, dated December 21, 
1989, has been accomplished: Within 5,000 flight cycles after 
accomplishment of that modification.
    (m) In lieu of the ``full'' modification required by paragraph 
(k) of this AD, the ``optional'' (partial) modification described in 
Boeing Service Bulletin 747-53-2307, Revision 2, dated October 14, 
1993; or Revision 3, dated April 16, 2009; may be accomplished for 
skin panels that have an outer thickness of 0.090 inches or less, 
and that do not have any cracks, corrosion, or an existing 
structural repair on the skin panel lap joint. After the effective 
date of this AD, only Revision 3 may be used. The ``optional'' 
(partial) modification shall not be accomplished at deep countersink 
fastener locations. Accomplishment of this modification terminates 
the repetitive inspection requirements of paragraph (g) of this AD.

New Requirements of This AD

Post-Modification Inspection at Reduced Intervals

    (n) Repeat the inspection required by paragraph (l) of this AD 
at the earlier of the times specified in paragraphs (n)(1) and 
(n)(2) of this AD. Thereafter, repeat the inspection at intervals 
not to exceed 1,000 flight cycles.
    (1) Within 3,000 flight cycles after the last inspection done in 
accordance with paragraph (l) of this AD.
    (2) Within 1,000 flight cycles after the last inspection done in 
accordance with paragraph (l) of this AD or 500 flight cycles after 
the effective date of this AD, whichever occurs later.

Post-Repair Inspection for External Doubler Repair

    (o) For all airplanes: Do an internal surface HFEC inspection 
for cracking of the skin at any external doubler repairs greater 
than 40 inches in length (in the horizontal direction) within 1,000 
flight cycles after the effective date of this AD, in accordance 
with the Accomplishment Instructions of Boeing Service Bulletin 747-
53-2307, Revision 3, dated April 16, 2009. Thereafter, perform that 
inspection at intervals not to exceed 3,000 flight cycles.
    (p) If any cracking is found during any inspection required by 
paragraph (o) of this AD, repair in accordance with the 
Accomplishment Instructions of Boeing Service Bulletin 747-53-2307, 
Revision 3, dated April 16, 2009.

Alternative Methods of Compliance (AMOCs)

    (q)(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: Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, 
Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., 
Renton, Washington 98057-3356; telephone (425) 917-6437; 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

[[Page 61980]]

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 an 
Authorized Representative for the Boeing Commercial Airplanes 
Organization Designation Authorization who 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.
    (4) AMOCs approved previously in accordance with AD 90-15-06, 
Amendment 39-6653; and AD 94-12-09, Amendment 39-8937; are approved 
as AMOCs for the corresponding provisions of this AD.

Material Incorporated by Reference

    (r) You must use Boeing Service Bulletin 747-53-2307, Revision 
3, dated April 16, 2009, to do the actions required by this AD, 
unless the AD specifies otherwise. If you accomplish the optional 
actions specified by this AD, you must use Boeing Service Bulletin 
747-53-2307, Revision 3, dated April 16, 2009, to perform those 
actions, unless the AD specifies otherwise.
    (1) The Director of the Federal Register approved the 
incorporation by reference of this service information under 5 
U.S.C. 552(a) and 1 CFR part 51.
    (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; e-mail 
me.boecom@boeing.com; Internet https://www.myboeingfleet.com.
    (3) You may review copies of the 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.
    (4) You may also review copies of the service information that 
is incorporated by reference at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call 202-741-6030, or go to: http://
www.archives.gov/federal_register/code_of_federal_regulations/
ibr_locations.html.

    Issued in Renton, Washington, on September 23, 2010.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-25019 Filed 10-6-10; 8:45 am]
BILLING CODE 4910-13-P

