Document ID: FAA-2010-0552-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Boeing Company Model 747-100, 747 200B, and 747 200F Series Airplanes
Posted Date: 2010-06-22T04:00Z

[Federal Register: June 22, 2010 (Volume 75, Number 119)]
[Proposed Rules]               
[Page 35356-35360]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr22jn10-17]                         

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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0552; Directorate Identifier 2009-NM-095-AD]
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: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to supersede two existing airworthiness 
directives (AD) that 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 
proposed AD would reduce the maximum interval of the post-modification 
inspections, and adds post-repair inspection requirements for certain 
airplanes. This proposed AD results from reports of cracking on 
modified airplanes. We are proposing 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: We must receive comments on this proposed AD by August 6, 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,

[[Page 35357]]

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 or 
425-227-1152.

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: 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: 

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-2010-0552; 
Directorate Identifier 2009-NM-095-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 July 3, 1990, we issued AD 90-15-06, Amendment 39-6653 (55 FR 
28600, July 12, 1990), for certain Boeing Model 747-100, 747-200B, and 
747-200F series airplanes. That AD 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. We issued that AD to detect and 
correct fatigue cracking and corrosion in the fuselage skins, which 
could lead to rapid decompression of the airplane and inability of the 
structure to carry fail-safe loads.
    On June 2, 1994, we issued AD 94-12-09, Amendment 39-8937 (59 FR 
30285, June 13, 1994), for certain Boeing Model 747-100, 747-200B, and 
747-200F series airplanes. That AD requires inspections to detect 
fatigue cracking and corrosion of the skin panel lap joints in the 
fuselage upper lobe, and repair if necessary. That AD also requires 
modification of certain lap joints and inspections of modified lap 
joints. That AD resulted from reports of cracking, corrosion, and 
bulging of the skin lap joints on Boeing Model 747-100, 747-200B, and 
747-200F series airplanes. We issued that AD to prevent rapid 
decompression of the airplane and the inability of the structure to 
carry fail-safe loads.

Actions Since Existing AD Was Issued

    Since we issued AD 94-12-09 and AD 90-15-06, Boeing has performed a 
fleet-wide evaluation of the skin panel lap joints for widespread 
fatigue damage (WFD) and determined that the post-modification 
inspection interval of AD 94-12-09 needs to be reduced. In addition, 
lap joints where the upper (overlapping) skin thickness at the upper 
row of fasteners is 0.071 inch or less need to be further modified to 
preclude WFD. WFD of the lap joints can link up and result in large 
skin cracks, and possible rapid in-flight decompression of the 
airplane.

Related Rulemaking

    We are considering issuing related rulemaking to address the 
identified unsafe condition. The related rulemaking would refer to 
Revision 1, dated April 16, 2009, of Boeing Service Bulletin 747-
53A2463, which is related to this unsafe condition. That AD would 
require further modification of all the affected lap joints with an 
upper skin thickness of 0.071 inch or less. Once the modification in 
accordance with Boeing Service Bulletin 747-53A2463 is accomplished, 
the post-modification inspections will be accomplished in accordance 
with that rule, not this one.

Relevant Service Information

    AD 90-15-06 refers to Boeing Service Bulletin 747-53-2307, dated 
December 21, 1989, as the appropriate source of service information for 
the required actions specified in that AD. AD 94-12-09 refers to Boeing 
Service Bulletin 747-53-2307, Revision 2, dated October 14, 1993, as 
the appropriate source of service information for the required actions 
specified in that AD. We have reviewed Boeing Service Bulletin 747-53-
2307, Revision 3, dated April 16, 2009. Boeing Service Bulletin 747-53-
2307, Revision 3, dated April 16, 2009, reduces the maximum post-
modification inspection interval specified in Boeing Service Bulletin 
747-53-2307, Revision 2, dated October 14, 1993, from 3,000 to 1,000 
flight cycles and references a structural modification for lap joints 
where the upper (overlapping) skin thickness at the upper row of 
fasteners is 0.071 inch or less. In addition, Boeing Service Bulletin 
747-53-2307, Revision 3, dated April 16, 2009, specifies a post-repair 
internal surface high frequency eddy current (HFEC) inspection of the 
skin at any external doubler repairs greater than 40 inches in length 
(in the horizontal direction).

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 90-15-06 and AD 94-12-09. This proposed AD does not 
retain any requirements of AD 90-15-06. This proposed AD would retain 
the inspection requirements of AD 94-12-09 but with reduced maximum 
intervals of the post-modification inspections from 3,000 flight cycles 
to 1,000 flight cycles. In addition, this proposed AD would require a 
post-repair internal surface HFEC inspection of the skin at any 
external doubler repairs greater than 40 inches in length (in the 
horizontal direction). This proposed AD would also require 
accomplishing the actions specified in Boeing Service Bulletin 747-53-
2307, Revision 3, dated April 16, 2009, described previously, except as 
discussed under ``Differences Between the Proposed AD and Service 
Bulletin.''

[[Page 35358]]

Differences Between the Proposed AD and Service Bulletin

    Boeing Service Bulletin 747-53-2307, Revision 3, dated April 16, 
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 that we have 
authorized to make those findings.

Change to Existing AD

    This proposed AD would retain the requirements of AD 94-12-09, and 
none of the requirements of AD 90-15-06. Since AD 94-12-09 was issued, 
the AD format has been revised, and certain paragraphs have been 
rearranged. 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
      Requirement in  AD 94-12-09                this proposed AD
------------------------------------------------------------------------
paragraph (a)..........................  paragraph (g).
paragraph (b)..........................  paragraph (h).
paragraph (c)..........................  paragraph (i).
paragraph (d)..........................  paragraph (j).
paragraph (e)..........................  paragraph (k).
paragraph (f)..........................  paragraph (l).
paragraph (g)..........................  paragraph (m).
------------------------------------------------------------------------

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 proposed AD.

                                                                     Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                 Number of
                                                          Average                                                  U.S.-
                  Action                    Work 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 by           56           85            0  $4,760 per inspection cycle.            7  $33,320 per inspection
 AD 94-12-09).                                                                                                                cycle.
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 39-6653 (55 FR 
28600, July 12, 1990), and Amendment 39-8937 (59 FR 30285, June 13, 
1994), and adding the following new AD:

The Boeing Company: Docket No. FAA-2010-0552; Directorate Identifier 
2009-NM-095-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by August 6, 
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.

[[Page 35359]]

Subject

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

Unsafe Condition

    (e) This AD results from reports of fatigue cracking. 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 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 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, use only Revision 3.
    (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, use only Revision 3. 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 (1)(1), (1)(2), and (1)(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.

[[Page 35360]]

    (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 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.

    Issued in Renton, Washington, on June 16, 2010.
Robert D. Breneman,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-15054 Filed 6-21-10; 8:45 am]
BILLING CODE 4910-13-P