Document ID: FAA-2008-1239-0006
Agency: faa
Document Type: Rule
Title: Airworthiness Directives; Boeing Model 747 Airplanes
Posted Date: 2009-05-07T04:00Z

[Federal Register: May 7, 2009 (Volume 74, Number 87)]
[Rules and Regulations]               
[Page 21249-21251]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07my09-3]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-1239; Directorate Identifier 2008-NM-131-AD; 
Amendment 39-15894; AD 2009-09-08]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 747 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
Boeing Model 747 airplanes. This AD requires repetitive external 
surface high frequency eddy current inspections to detect cracks in the 
radius detail of the upper lobe doubler on both sides of the airplane, 
and applicable corrective action. This AD results from reports of 
cracks in the radius detail of the upper lobe doublers. We are issuing 
this AD to detect and correct cracks in the upper lobe doublers. Such 
cracks could result in significant degradation of the fuselage 
structure and reduce its ability to carry flight loads from the 
vertical stabilizer, which could adversely affect the controllability 
of the airplane.

DATES: This AD is effective June 11, 2009.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of June 11, 
2009.

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

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an airworthiness directive (AD) that would apply to 
certain Boeing Model 747 airplanes.

[[Page 21250]]

That NPRM was published in the Federal Register on November 26, 2008 
(73 FR 71963). That NPRM proposed to require repetitive external 
surface high frequency eddy current (HFEC) inspections to detect cracks 
in the radius detail of the upper lobe doubler on both sides of the 
airplane, and applicable corrective action.

Comments

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

Support for Proposed AD

    Boeing concurs with the contents of the proposed AD. Northwest 
Airlines (NWA) has no technical objection to the initial and repetitive 
HFEC inspections and corrective actions specified in the proposed AD.

Request To Include Service Bulletin Information Notice

    NWA requests that the information in Boeing Service Bulletin 
Information Notice (IN) 747-53A2651 IN 01, dated November 6, 2008, be 
acknowledged and accounted for in the final rule.
    We partially agree. Changes to Boeing Alert Service Bulletin 747-
53A2651, dated June 12, 2008, are discussed below, along with our 
response to the commenter about these changes.
     The IN notes that in Figures 1 and 2, footnote (b), of 
Boeing Alert Service Bulletin 747-53A2651, dated June 12, 2008, the 
existing probe part number ``MMP950-50'' should be ``MMP905-50.'' The 
existing part number of the probe (for the HFEC inspection) in the 
service bulletin has a typographical error. The part number is provided 
in Boeing Alert Service Bulletin 747-53A2651, dated June 12, 2008, only 
as an example of an acceptable probe, and is not mandated by this AD. 
Therefore, we have not changed this AD regarding this issue.
     The IN also notes that in Figures 1 and 2, footnote (b), 
of Boeing Alert Service Bulletin 747-53A2651, dated June 12, 2008, 
additional examples of the small diameter probe part numbers ``MMP901-
50'' and ``MMP-60'' should be added, and that Boeing wants to provide 
the operators with more examples of acceptable probes. As use of a 
specific small diameter probe is not mandated, this AD has not been 
changed regarding this issue.
     The IN also notes that in Paragraph 3.B., Work 
Instructions, PART 3, Step 1, of Boeing Alert Service Bulletin 747-
53A2651, dated June 12, 2008, the existing text ``from STA 2520 to STA 
2521'' should be ``from STA 2491 to STA 2521.'' The existing text is a 
typographical error in ``Part 3--Restoration'' of the Work Instructions 
of Boeing Alert Service Bulletin 747-53A2651, dated June 12, 2008, and 
it is related to the location of a sealant application. The service 
bulletin does define the inspection area as ``between STA 2491 and STA 
2521'' in the Action paragraph and the service bulletin shows the same 
area to be inspected in the figures. It is Boeing's intent in the 
service bulletin to apply sealant to the inspected area. We have 
clarified this issue by adding a new paragraph (g) to this final rule 
and re-identified subsequent paragraphs accordingly.

Request To Change Work Hours

    NWA requests that we change the work-hour estimate provided in the 
proposed AD to include the time to remove and restore the sealant--for 
a total of 25 work hours.
    We disagree. The cost information describes only the direct costs 
of the specific actions required by this AD. Based on the best data 
available, the manufacturer provided the number of work hours necessary 
to do the required actions. This number represents the time necessary 
to perform only the actions actually required by this AD. Removing the 
sealant is addressed in paragraph 3.B. ``Part 1--Access,'' of Boeing 
Alert Service Bulletin 747-53A2651, dated June 12, 2008, and 
restoration of the sealant is addressed in paragraph 3.B. ``Part 3--
Restoration,'' in the Work Instructions of the service bulletin. We 
recognize that, in doing the actions required by an AD, operators might 
incur incidental costs in addition to the direct costs. The cost 
analysis in AD rulemaking actions, however, typically does not include 
incidental costs such as the time required to gain access and close up. 
Those incidental costs, which might vary significantly among operators, 
are almost impossible to calculate. This AD has not been changed 
regarding this issue.

Explanation of Change to Paragraph (f) of This AD

    We have revised paragraph (f) of this AD to clarify that there is 
an initial inspection that must be done for all airplanes and that the 
repetitive inspections must be done for airplanes on which no cracking 
is found.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
the AD with the changes described previously. We also determined that 
these changes will not increase the economic burden on any operator or 
increase the scope of the AD.

Costs of Compliance

    We estimate that this AD will affect 164 airplanes of U.S. 
registry. We also estimate that it will take 9 work-hours per product 
to comply with this AD. The average labor rate is $80 per work-hour. 
Based on these figures, we estimate the cost of this AD to the U.S. 
operators to be $118,080, or $720 per product, per inspection 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

    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.
    You can find our regulatory evaluation and the estimated costs of 
compliance in the AD Docket.

[[Page 21251]]

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

2009-09-08 Boeing: Amendment 39-15894. Docket No. FAA-2008-1239; 
Directorate Identifier 2008-NM-131-AD.

Effective Date

    (a) This airworthiness directive (AD) is effective June 11, 
2009.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing 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 Alert Service Bulletin 747-
53A2651, dated June 12, 2008.

Unsafe Condition

    (d) This AD results from reports of cracks in the radius detail 
of the upper lobe doublers. We are issuing this AD to detect and 
correct cracks in the upper lobe doublers. Such cracks could result 
in significant degradation of the fuselage structure and reduce its 
ability to carry flight loads from the vertical stabilizer, which 
could adversely affect the controllability of the airplane.

Compliance

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

Inspection(s) and Corrective Action

    (f) At the applicable times specified in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 747-53A2651, dated 
June 12, 2008, except as required by paragraph (i) of this AD, do an 
external surface high frequency eddy current inspection to detect 
cracks in the radius detail of the upper lobe doubler on both sides 
of the airplane, and the applicable corrective action, by 
accomplishing all the applicable actions specified in the 
Accomplishment Instructions of the service bulletin, except as 
required by paragraphs (g) and (h) of this AD. The applicable 
corrective action must be done before further flight. As applicable, 
repeat the inspection thereafter at the applicable times specified 
in paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
747-53A2651, dated June 12, 2008.
    (g) Where Boeing Alert Service Bulletin 747-53A2651, dated June 
12, 2008, paragraph 3.B., Work Instructions, PART 3, Step 1, 
specifies a sealant application ``from STA 2520 to STA 2521,'' this 
AD requires a sealant application ``from STA 2491 to STA 2521'' on 
both sides of the airplane.
    (h) Where Boeing Alert Service Bulletin 747-53A2651, dated June 
12, 2008, specifies to contact Boeing for repair instructions 
instead of repairing or replacing any cracked upper lobe doubler in 
accordance with the service bulletin, this AD requires, before 
further flight, repairing any cracked upper lobe doubler using a 
method approved in accordance with the procedures specified in 
paragraph (j) of this AD.
    (i) Where Boeing Alert Service Bulletin 747-53A2651, dated June 
12, 2008, specifies a compliance time after the date on the service 
bulletin, this AD requires compliance within the specified 
compliance time after the effective date of this AD.

Alternative Methods of Compliance (AMOCs)

    (j)(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 ACO, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; 
telephone (425) 917-6437; fax (425) 917-6590.
    (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 
Delegation Option Authorization Organization 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.

Material Incorporated by Reference

    (k) You must use Boeing Alert Service Bulletin 747-53A2651, 
dated June 12, 2008, to do the actions required by this AD, 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 or 425-227-1152.
    (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 April 22, 2009.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E9-9925 Filed 5-6-09; 8:45 am]

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