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[Federal Register Volume 75, Number 223 (Friday, November 19, 2010)]
[Proposed Rules]
[Pages 70863-70868]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-29231]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0090; Directorate Identifier 2007-NM-312-AD]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Model 747 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 Model 747 airplanes. The original NPRM would have 
required measuring the electrical bond resistance between the motor 
operated valve (MOV) actuators and airplane structure for the main, 
center, auxiliary, and horizontal stabilizer fuel tanks, as applicable, 
and corrective action if necessary. The original NPRM also would have 
required a revision to the maintenance program to incorporate 
airworthiness limitation (AWL) No. 28-AWL-21 or AWL No. 28-AWL-27, as 
applicable. The original NPRM resulted from fuel system reviews 
conducted by the manufacturer. This supplemental NPRM would revise the 
original NPRM by adding airplanes to the applicability, and would 
require replacing production-installed laminate phenolic spacers with 
metallic spacers between the fuel jettison MOV and the airplane 
structure, as applicable. We are proposing this supplemental NPRM to 
prevent electrical current from flowing through an MOV actuator into a 
fuel tank, which could create a potential ignition source inside the 
fuel tank. This condition, in combination with flammable fuel vapors, 
could result in a fuel tank explosion and consequent loss of the 
airplane.

DATES: We must receive comments on this supplemental NPRM by December 
14, 2010.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-
544-5000, extension 1; fax 206-766-5680; e-mail me.boecom@boeing.com; 
Internet https://www.myboeingfleet.com. You may review copies of the 
referenced

[[Page 70864]]

service information at the FAA, Transport Airplane Directorate, 1601 
Lind Avenue, SW., Renton, Washington. For information on the 
availability of this material at the FAA, call 425-227-1221.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Douglas Bryant, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone 
(425) 917-6505; 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-2008-0090; 
Directorate Identifier 2007-NM-312-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 a notice of proposed rulemaking (NPRM) (the ``original 
NPRM'') to amend 14 CFR part 39 to include an airworthiness directive 
(AD) that would apply to certain Model 747 airplanes. That original 
NPRM was published in the Federal Register on January 31, 2008 (73 FR 
5773). That original NPRM proposed to require measuring the electrical 
bond resistance between the motor operated valve (MOV) actuators and 
airplane structure for the main, center, auxiliary, and horizontal 
stabilizer fuel tanks, as applicable, and corrective action if 
necessary. That original NPRM also proposed to require a revision to 
the maintenance program to incorporate airworthiness limitation (AWL) 
No. 28-AWL-21 or AWL No. 28-AWL-27, as applicable.

Actions Since Original NPRM Was Issued

    Since we issued the original NPRM, we reviewed Boeing Service 
Bulletin 747-28A2292, Revision 2, dated May 13, 2010 (for Model 747-
100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 
747-400, 747-400D, 747-400F, 747SR, and 747SP series airplanes). This 
service bulletin clarifies the procedure for measuring the electrical 
bond resistance, and adds procedures for replacing production-installed 
laminate phenolic spacers with metallic spacers for airplanes in Groups 
12, 16, 17, 18, and 19. This service bulletin also adds airplanes to 
the Effectivity. Paragraphs (c) and (g) of this supplemental NPRM have 
been revised accordingly.
    We also reviewed Boeing Service Bulletin 747-28A2294, Revision 1, 
dated March 5, 2009 (for Model 747-400 series airplanes equipped with 
an active horizontal stabilizer fuel tank). This service bulletin is 
the same as the original issue, dated September 21, 2007, except that a 
reference to Sub-section 28-17-03 of Boeing 747-400 Airplane 
Maintenance Manual (AMM) is corrected in Revision 1.
    We reviewed Boeing 747-100/200/300/SP Airworthiness Limitations 
(AWLs) and Certification Maintenance Requirements (CMRs), Document D6-
13747-CMR, Revision March 2008 (hereafter referred to as ``Document D6-
13747-CMR''). (We referred to Revision January 2007 of Document D6-
13747-CMR in the original NPRM.) Document D6-13747-CMR revises certain 
AWLs for fuel tank systems. However, AWL No. 28-AWL-21, which is 
specified in this supplemental NPRM, has not been revised in Document 
D6-13747-CMR, Revision March 2008.
    We also reviewed the Boeing 747-400 Maintenance Planning Data (MPD) 
Document, Section 9, D621U400-9, Revision December 2009 (hereafter 
referred to as ``Boeing 747-400 MPD''). Among other things, Subsection 
D of Boeing 747-400 MPD has been revised to clarify the 
``Applicability'' of AWL No. 28-AWL-27, which is a critical design 
configuration control limitation (CDCCL) to maintain the design 
features of the MOV actuator.
    We have revised this supplemental NPRM to refer to the latest 
service information described previously.

Other Relevant Rulemaking

    On April 28, 2008, we issued AD 2008-10-07, Amendment 39-15513 (73 
FR 25977, May 8, 2008); and on October 30, 2009, we issued AD 2008-10-
07 R1, Amendment 39-16070 (74 FR 56098, November 16, 2009); applicable 
to all Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-
200C, 747-200F, 747-300, 747SR, and 747SP series airplanes. Those ADs 
require revising the maintenance program by incorporating new AWLs for 
fuel tank systems to satisfy Special Federal Aviation Regulation No. 88 
(``SFAR 88'') requirements. As an optional action, those ADs also allow 
incorporating AWL No. 28-AWL-21 into the maintenance program. 
Therefore, we have added a new paragraph (n) to this supplemental NPRM 
to specify that incorporating AWL No. 28-AWL-21 into the maintenance 
program in accordance with paragraph (g) of AD 2008-10-07 or 2008-10-07 
R1 terminates the action required by paragraph (k) of this supplemental 
NPRM for the applicable airplanes.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We considered the comments received from the three commenters.

Request To Allow Use of Future Revisions of the Service Bulletins

    Boeing requested that we revise the original NPRM to specify that 
the proposed modifications may also be done in accordance with any 
future-approved revisions to Boeing Alert Service Bulletin 747-28A2292, 
dated September 14, 2007; and Boeing Alert Service Bulletin 747-
28A2294, dated September 21, 2007. As justification, Boeing stated that 
these service bulletins could be revised by the time we issue the AD.
    We partially agree. As discussed previously, we have revised this 
supplemental NPRM to refer to the most recently issued service 
information. However, we do not agree to refer to ``later revisions.'' 
To allow operators to use later revisions of the referenced service 
documents, either we must revise the AD to reference specific later 
revisions, or operators must request approval to use later revisions as 
an alternative method of compliance with the AD. Therefore, we have 
removed all references to the use of a ``later revision'' of the 
applicable service information from this supplemental NPRM to be

[[Page 70865]]

consistent with FAA policy. We may consider approving the use of later 
revisions of the service information as an AMOC with this AD, as 
provided by paragraph (q) of this supplemental NPRM.

Request To Revise Paragraphs (h) and (i) of the Original NPRM

    KLM Royal Dutch Airlines (KLM) stated that the intent of the 
original NPRM is to maintain the design features introduced in 
accordance with Boeing Alert Service Bulletin 747-28A2292, dated 
September 14, 2007; and Boeing Alert Service Bulletin 747-28A2294, 
dated September 21, 2007; respectively; when an MOV actuator is 
installed. KLM thought that it was clearer if the NPRM stated that the 
CDCCLs must be incorporated into the applicable paragraphs of the AMM 
to maintain these design features.
    We infer that KLM requests that we revise paragraphs (h) and (i) of 
the NPRM as proposed above. We disagree with the commenter's request. 
We disagree that incorporating CDCCLs into the AMM is the appropriate 
location for a CDCCL. The AMM is not an FAA-approved document. The 
appropriate location for a CDCCL is in the FAA-approved section (i.e., 
the Airworthiness Limitations section) of an operator's maintenance 
program. We have not changed this supplemental NPRM in this regard.

Request To Exclude a Certain Airplane From the Requirements of 
Paragraph (g) of the Original NPRM

    Lufthansa requested that we exclude a certain Model 747-400 series 
airplane from paragraph (g) of the original NPRM because the horizontal 
stabilizer tank (HST) on that airplane has never been activated.
    We disagree with the request. Although the HST might not be 
activated at this time, it could be activated in the future. We cannot 
exclude an airplane from the requirements of this supplemental NPRM 
without substantiation that the unsafe condition has been adequately 
addressed. We have not changed this supplemental NPRM in this regard.

Request To Extend Compliance Time

    Lufthansa requested that we extend the compliance time of the 
original NPRM from 60 months to 72 months. Lufthansa stated that this 
extension will allow operators to implement the modification at the 
next maintenance layover.
    KLM requested that we extend the compliance time of the original 
NPRM from 60 months to 96 months. KLM stated that tank entry might be 
necessary for accomplishing the actions, and KLM wanted to avoid tank 
entry during C-checks.
    We disagree with the commenters' requests to extend the compliance 
time. In developing an appropriate compliance time for this 
supplemental NPRM, we considered the urgency associated with the 
subject unsafe condition and the practical aspect of accomplishing the 
required actions on the Model 747 fleet in a timely manner. We 
recognize that operators may have different schedules for accomplishing 
heavy maintenance, but at the same time, we find that the 60-month 
compliance time will include most operators' schedules for that type of 
work. Further, according to the provisions of paragraph (q) of this AD, 
we may consider approving requests to adjust the compliance time if 
those requests include data that prove that the new compliance time 
would provide an acceptable level of safety. No change to this 
supplemental NPRM is necessary in this regard.

Other Change Made to This Supplemental NPRM

    We have added a new paragraph (m) to this supplemental NPRM to 
specify that no alternative CDCCLs may be used unless they are approved 
as an AMOC. Inclusion of this paragraph in the supplemental NPRM is 
intended to ensure that the AD-mandated airworthiness limitations 
changes are treated the same as the airworthiness limitations issued 
with the original type certificate.

FAA's Determination and Proposed Requirements of the Supplemental NPRM

    We are proposing this supplemental NPRM because we evaluated all 
pertinent information and determined an unsafe condition exists and is 
likely to exist or develop on other products of the same type design. 
Certain changes described above expand the scope of the original NPRM. 
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.

Explanation of Change to Costs of Compliance

    Since issuance of the original NPRM, we have increased the labor 
rate used in the Costs of Compliance form $80 per work-hour to $85 per 
work-hour. The Costs of Compliance information, below, reflects this 
increase in the specified hourly labor rate.
    For convenience to the operator, the Estimated Costs table, below, 
was revised to break out the cost of replacing the spacers and the on-
condition costs.

Costs of Compliance

    We estimate that this proposed AD will affect 222 airplanes of U.S. 
registry.
    We estimate the following costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                  Cost on U.S.
             Action                    Labor cost            Parts cost      Cost per product      operators
----------------------------------------------------------------------------------------------------------------
Measurement....................  Up to 7 work-hours x    Up to $350.......  Up to $945.......  Up to $209,790.
                                  $85 per hour = Up to
                                  $595.
Replacement (Up to 60            Up to 4 work-hours x    $1,305...........  Up to $1,645.....  Up to $98,700.
 airplanes).                      $85 per hour = Up to
                                  $340.
Maintenance program revision...  1 work-hour x $85 per   $0...............  $85..............  $18,870.
                                  hour = $85.
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    We estimate the following costs to do any necessary modification 
that would be required based on the results of the proposed inspection. 
We have no way of determining the number of aircraft that might need 
this modification:

[[Page 70866]]

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
              Action                      Labor cost             Parts cost              Cost per product
----------------------------------------------------------------------------------------------------------------
Change electrical bond and rework   436 work-hours x $85   Up to $35,760........  Up to $72,820.
 part contact surface.               per hour = $37,060.
----------------------------------------------------------------------------------------------------------------

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. ``Subtitle VII: Aviation 
Programs,'' describes in more detail the scope of the Agency's 
authority.
    We are issuing this rulemaking under the authority described in 
``Subtitle VII, Part A, Subpart III, Section 44701: General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would not 
have a substantial direct effect on the States, on the relationship 
between the national Government and the States, or on the distribution 
of power and responsibilities among the various levels of government.
    For the reasons discussed above, I certify this proposed 
regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866,
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979), and
    3. Will not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.
    You can find our regulatory evaluation and the estimated costs of 
compliance in the AD Docket.

List of Subjects in 14 CFR Part 39

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

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec.  39.13  [Amended]

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

The Boeing Company: Docket No. FAA-2008-0090; Directorate Identifier 
2007-NM-312-AD.

Comments Due Date

    (a) We must receive comments by December 14, 2010.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 
747-400D, 747-400F, 747SR, and 747SP series airplanes, certificated 
in any category; as identified in Boeing Service Bulletin 747-
28A2292, Revision 2, dated May 13, 2010.

    Note 1: This AD requires revisions to certain operator 
maintenance documents to include new inspections. Compliance with 
these inspections is required by 14 CFR 91.403(c). For airplanes 
that have been previously modified, altered, or repaired in the 
areas addressed by these inspections, the operator may not be able 
to accomplish the inspections described in the revisions. In this 
situation, to comply with 14 CFR 91.403(c), the operator must 
request approval for an alternative method of compliance (AMOC) 
according to paragraph (q) of this AD. The request should include a 
description of changes to the required inspections that will ensure 
the continued operational safety of the airplane.

Subject

    (d) Air Transport Association (ATA) of America Code 28: Fuel.

Unsafe Condition

    (e) This AD results from fuel system reviews conducted by the 
manufacturer. The Federal Aviation Administration is issuing this AD 
to prevent electrical current from flowing through a motor operated 
valve (MOV) actuator into a fuel tank, which could create a 
potential ignition source inside the fuel tank. This condition, in 
combination with flammable fuel vapors, could result in a fuel tank 
explosion and consequent loss 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.

Measurement, Corrective Action, and Replacement

    (g) Within 60 months after the effective date of this AD, do the 
actions required by paragraphs (g)(1) and (g)(2) of this AD, as 
applicable.
    (1) Measure the electrical bond resistance between the MOV 
actuators and the airplane structure for the main, center, and 
auxiliary fuel tanks, as applicable; and do all applicable 
corrective actions; by accomplishing all of the applicable actions 
in the Accomplishment Instructions of Boeing Service Bulletin 747-
28A2292, Revision 2, dated May 13, 2010. The corrective actions must 
be accomplished before further flight.
    (2) For airplanes in Groups 12, 16, 17, 18, and 19, as 
identified in Boeing Service Bulletin 747-28A2292, Revision 2, dated 
May 13, 2010: Within 60 months after the effective date of this AD, 
replace production-installed laminate phenolic spacers with metallic 
spacers, in accordance with the Accomplishment Instructions of 
Boeing Service Bulletin 747-28A2292, Revision 2, dated May 13, 2010.
    (h) For airplanes identified in Boeing Service Bulletin 747-
28A2294, Revision 1, dated March 5, 2009: Within 60 months after the 
effective date of this AD, measure the electrical bond resistance 
between the MOV actuators and airplane structure for the horizontal 
stabilizer (HST) fuel tanks, and do all the applicable corrective 
actions, in accordance with the Accomplishment Instructions of 
Boeing Service Bulletin 747-28A2294, Revision 1, dated March 5, 
2009. The corrective actions must be accomplished before further 
flight.

Deactivation of the HST

    (i) For airplanes identified in Boeing Service Bulletin 747-
28A2294, Revision 1, dated March 5, 2009: Deactivation of the HST, 
in accordance with the applicable Boeing service information 
specified in Table 1 of this AD, terminates the requirements of 
paragraph (h) of this AD, except as provided by paragraph (j) of 
this AD. Deactivation of the HST before the effective date of this 
AD in accordance with the applicable service information specified 
in Table 2 of this AD also terminates the requirements of paragraph 
(h) of this AD, except as provided by paragraph (j) of this AD.

[[Page 70867]]

                Table 1--Deactivation Service Information
------------------------------------------------------------------------
           Boeing--               Revision--             Dated--
------------------------------------------------------------------------
Service Bulletin 747-28-2265.  Original........  February 22, 2006.
Service Bulletin 747-28-2272.  Original........  February 21, 2006.
Service Bulletin 747-28-2274.  1...............  May 21, 2008.
Service Bulletin 747-28-2275.  4...............  February 2, 2009.
Service Bulletin 747-28-2279.  2...............  October 16, 2007.
Service Bulletin 747-28-2285.  3...............  August 30, 2007.
Service Bulletin 747-28-2293.  2...............  March 4, 2008.
Service Bulletin 747-28-2295.  2...............  January 19, 2009.
Service Bulletin 747-28-2296.  Original........  July 13, 2007.
Service Bulletin 747-28-2300.  1...............  June 2, 2008.
Service Bulletin 747-28-2314.  Original........  December 9, 2008.
------------------------------------------------------------------------

            Table 2--Deactivation Credit Service Information
------------------------------------------------------------------------
           Boeing--               Revision--             Dated--
------------------------------------------------------------------------
Service Bulletin 747-28-2274.  Original........  March 13, 2006.
Service Bulletin 747-28-2275.  Original........  June 12, 2006.
Service Bulletin 747-28-2275.  1...............  March 16, 2007.
Service Bulletin 747-28-2275.  2...............  July 2, 2007.
Service Bulletin 747-28-2275.  3...............  March 11, 2008.
Service Bulletin 747-28-2279.  Original........  June 12, 2006.
Service Bulletin 747-28-2279.  1...............  May 25, 2007.
Service Bulletin 747-28-2285.  Original........  January 23, 2007.
Service Bulletin 747-28-2285.  1...............  May 9, 2007.
Service Bulletin 747-28-2285.  2...............  August 3, 2007.
Service Bulletin 747-28-2293.  Original........  May 9, 2007.
Service Bulletin 747-28-2293.  1...............  August 29, 2007.
Service Bulletin 747-28-2295.  Original........  November 17, 2006.
Service Bulletin 747-28-2295.  1...............  March 20, 2008.
Service Bulletin 747-28-2300.  Original........  January 16, 2008
------------------------------------------------------------------------

Reactivation of the HST

    (j) For airplanes identified Boeing Service Bulletin 747-
28A2294, Revision 1, dated March 5, 2009, on which the HST is 
reactivated, the HST must be reactivated in accordance with a method 
approved by the Manager, Seattle Aircraft Certification Office 
(ACO), FAA. For any airplane on which the HST is reactivated, the 
requirements of paragraphs (h) and (l) of this AD must be done 
before further flight following the reactivation, or within 60 
months after the effective date of this AD, whichever occurs later. 
For a reactivation method to be approved, the reactivation method 
must meet the certification basis of the airplane, and the approval 
must specifically reference this AD.

Maintenance Program Revision

    (k) For Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-
200C, 747-200F, 747-300, 747SR, and 747SP series airplanes: 
Concurrently with accomplishing the actions required by paragraph 
(g) of this AD, revise the maintenance program by incorporating 
airworthiness limitation (AWL) No. 28-AWL-21 of Section D of Boeing 
747-100/200/300/SP Airworthiness Limitations (AWLs) and 
Certification Maintenance Requirements (CMRs), Document D6-13747-
CMR, Revision March 2008.
    (l) For Model 747-400, 747-400D, and 747-400F series airplanes: 
Concurrently with accomplishing the actions required by paragraph 
(g) of this AD, revise the maintenance program by incorporating AWL 
No. 28-AWL-27 of Subsection D of Boeing 747-400 Maintenance Planning 
Data (MPD) Document, Section 9, D621U400-9, Revision December 2009.

No Alternative Critical Design Configuration Control Limitations 
(CDCCLs)

    (m) After accomplishing the applicable action required in 
paragraph (k) or (l) of this AD, no alternative CDCCLs may be used 
unless the CDCCLs are approved as an AMOC in accordance with the 
procedures specified in paragraph (q) of this AD.

Terminating Action for Maintenance Program Revision

    (n) For Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-
200C, 747-200F, 747-300, 747SR, and 747SP series airplanes: 
Incorporating AWL No. 28-AWL-21 into the maintenance program in 
accordance with paragraph (g) of AD 2008-10-07, Amendment 39-15513; 
or AD 2008-10-07 R1, Amendment 39-16070; terminates the action 
required by paragraph (k) of this AD.

Actions Accomplished According to Previous Issue of Service Bulletin

    (o) Actions done before the effective date of this AD, in 
accordance with Boeing Alert Service Bulletin 747-28A2294, dated 
September 21, 2007, are acceptable for compliance with the 
corresponding requirements of this AD.

Incorporation of Previous Issues of Airworthiness Limitation (AWL)

    (p) Incorporation of AWL No. 28-AWL-21 of Section D of the 
Boeing 747-100/200/300/SP Airworthiness Limitations (AWLs) and 
Certification Maintenance Requirements (CMRs), Document D6-13747-
CMR, Revision January 2007, September 2007, or January 2008, is 
acceptable for compliance with the corresponding requirements of 
this AD if done before the effective date of this AD.

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: Douglas Bryant, Aerospace Engineer, Propulsion Branch, ANM-
140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, 
SW., Renton, Washington 98057-3356; telephone (425) 917-6505; fax 
(425) 917-6590. Information may be e-mailed 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

[[Page 70868]]

Office. The AMOC approval letter must specifically reference this 
AD.

    ssued in Renton, Washington on November 10, 2010.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-29231 Filed 11-18-10; 8:45 am]
BILLING CODE 4910-13-P
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