Document ID: FAA-2011-0041-0007
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Boeing Co. Model 747-400 and -400F Series Airplanes
Posted Date: 2011-08-05T04:00Z

[Federal Register Volume 76, Number 151 (Friday, August 5, 2011)]
[Rules and Regulations]
[Pages 47427-47430]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-19828]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0041; Directorate Identifier 2010-NM-227-AD; 
Amendment 39-16764; AD 2011-16-06]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Model 747-400 and -
400F Series Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for the 
products listed above. This AD requires a general visual inspection for 
cracks and holes of the main equipment center (MEC) drip shields, and 
repairs if necessary; installation of a fiberglass reinforcing 
overcoat; and, for certain airplanes, installation of stiffening panels 
to the MEC drip shields. This AD was prompted by a report of a loss of 
bus control unit number 1 and generator control units numbers 1 and 2 
while the airplane was on the ground, and multiple operator reports of 
cracked

[[Page 47428]]

MEC drip shields. We are issuing this AD to prevent water penetration 
into the MEC, which could result in the loss of flight critical 
systems.

DATES: This AD is effective September 9, 2011.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of September 9, 
2011.

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; phone: 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.

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 (phone: 800-647-5527) is 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: Francis Smith, Aerospace Engineer, 
Cabin Safety & Environmental Systems Branch, ANM-150S, FAA, Seattle 
Aircraft Certification Office (ACO), 1601 Lind Avenue, SW., Renton, 
Washington 98057-3356; phone: 425-917-6596; fax: 425-917-6590; e-mail: 
Francis.Smith@faa.gov.

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 
the specified products. That NPRM published in the Federal Register on 
February 10, 2011 (76 FR 7513). The NPRM proposed a general visual 
inspection for cracks and holes of the main equipment center (MEC) drip 
shields, and repairs if necessary; installation of a fiberglass 
reinforcing overcoat; and, for certain airplanes, installation of 
stiffening panels to the MEC drip shields.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the proposal 
and the FAA's response to each comment.

Request To Reference Latest Service Bulletin Revision

    Both UPS and Boeing requested that we revise the NPRM to require 
that actions be done in accordance with Boeing Alert Service Bulletin 
747-25A3588, Revision 1, dated April 7, 2011. The NPRM referred to 
Boeing Alert Service Bulletin 747-25A3588, dated July 19, 2010, as the 
appropriate source of service information for the required actions.
    We agree. Boeing Alert Service Bulletin 747-25A3588, Revision 1, 
dated April 7, 2011, removes airplane RT101 from this service 
information effectivity and provides operators with additional material 
options. The procedures remain unchanged. We revised paragraphs (c), 
(g), (g)(1), and (g)(2) in this final rule to refer to Boeing Alert 
Service Bulletin 747-25A3588, Revision 1, dated April 7, 2011. We added 
new paragraph (h) to the final rule to give credit for actions done 
before the effective date of this AD in accordance with Boeing Alert 
Service Bulletin 747-25A3588, dated July 19, 2010, and re-identified 
subsequent paragraphs accordingly.

Request To Extend the Compliance Time

    UPS stated concern with Boeing's ability to provide adequate 
modification kits to all affected operators within the proposed 24-
month compliance time. UPS justified its concern by stating that the 
NPRM acknowledges it would affect an estimated 41 airplanes of U.S. 
registry. UPS stated that worldwide, there are more than 150 Model 747-
400F airplanes that are affected by the referenced service information 
and many may attempt to accomplish this modification within the 24-
month compliance time. At the time, Boeing had indicated it had 
materials available to produce only 6 kits, and will require 190 days 
lead time to replenish the stock. As the referenced service information 
specifies to install the parts provided in the kit by part number, an 
alternative method of compliance (AMOC) would be required for any 
operators needing to fabricate their own modification parts from raw 
materials, if Boeing is unable to provide the required modification 
kits in a timely basis for the proposed installation.
    We infer that UPS is requesting that we extend the proposed 
compliance time. Boeing Alert Service Bulletin 747-25A3588, dated July 
19, 2010; and Revision 1, dated April 7, 2011; were both coordinated 
between Boeing and the FAA. Proposed methods of compliance and the 
compliance time were weighed versus uncorrected risks in determining an 
acceptable and feasible corrective action. Boeing is most familiar with 
its ability to supply operators with instructions and kits to meet AD 
compliance, and determined it would be capable of reasonably achieving 
a 24-month compliance time with the proposed methods, when both Boeing 
Alert Service Bulletin 747-25A3588, dated July 19, 2010; and Revision 
1, dated April 7, 2011; were drafted and approved. Although kits may 
not be available immediately for every airplane, Boeing has advised us 
that it is capable of creating and delivering additional kits for 
operators to use within the AD compliance time.
    Once we issue this AD, any person may request approval of an AMOC 
under the provisions of paragraph (i) of this AD. We have not changed 
this AD in this regard.

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 change described previously. We also determined that 
this change will not increase the economic burden on any operator or 
increase the scope of the AD.

Costs of Compliance

    We estimate that this AD affects 41 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

[[Page 47429]]

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
              Action                      Labor cost             Parts cost           product        operators
----------------------------------------------------------------------------------------------------------------
Inspection and installation:        20 work-hours x $85    $1,109...............          $2,809         $67,416
 Groups 1, 3 (24 airplanes).         per hour = $1,700.
Inspection and installation: Group  17 work-hours x $85    Negligible...........           1,445          24,565
 2 (17 airplanes).                   per hour = $1,445.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary repairs that 
would be required based on the results of the inspection. We have no 
way of determining the number of aircraft that might need these 
repairs.

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                Action                        Labor cost               Parts cost           Cost per airplane
----------------------------------------------------------------------------------------------------------------
Hole repair..........................  1 work-hour x $85 per    Negligible.............  $85 per hole.
                                        hour = $85 per hole.
----------------------------------------------------------------------------------------------------------------

    According to the manufacturer, some of the costs of this AD may be 
covered under warranty, thereby reducing the cost impact on affected 
individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all costs in our cost 
estimate.

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),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

    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 airworthiness 
directive (AD):

2011-16-06 The Boeing Company: Amendment 39-16764; Docket No. FAA-
2011-0041; Directorate Identifier 2010-NM-227-AD.

Effective Date

    (a) This AD is effective September 9, 2011.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to The Boeing Company Model 747-400 and -
400F series airplanes, certificated in any category, as identified 
in Boeing Alert Service Bulletin 747-25A3588, Revision 1, dated 
April 7, 2011.

Subject

    (d) Joint Aircraft System Component (JASC)/Air Transport 
Association (ATA) of America Code 25: Equipment/Furnishings.

Unsafe Condition

    (e) This AD was prompted by a report of a loss of bus control 
unit number 1 and generator control units numbers 1 and 2 while the 
airplane was on the ground, and multiple operator reports of cracked 
main equipment center (MEC) drip shields. We are issuing this AD to 
prevent water penetration into the MEC, which could result in the 
loss of flight critical systems.

Compliance

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

Inspection

    (g) Within 24 months after the effective date of this AD, do the 
actions specified in paragraph (g)(1) or (g)(2) of this AD, as 
applicable, in accordance with the Accomplishment Instructions of 
Boeing Alert Service Bulletin 747-25A3588, Revision 1, dated April 
7, 2011.
    (1) For Group 1 and Group 3 airplanes, as identified in Boeing 
Alert Service Bulletin 747-25A3588, Revision 1, dated April 7, 2011: 
Do a general visual inspection of the MEC drip shield to detect 
cracking and holes, do all applicable repairs, and install the MEC 
drip shield panel stiffeners and the fiberglass reinforcing overcoat 
to the MEC drip shield, in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-25A3588, Revision 
1, dated April 7, 2011. Do all applicable repairs before further 
flight.
    (2) For Group 2 airplanes, as identified in Boeing Alert Service 
Bulletin 747-25A3588, Revision 1, dated April 7, 2011: Do a general 
visual inspection of the MEC drip shield to detect cracking and 
holes, do all applicable repairs, and install the fiberglass 
reinforcing overcoat to the MEC drip shield, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
25A3588, Revision 1, dated April 7, 2011. Do all applicable repairs 
before further flight.

[[Page 47430]]

Credit for Actions Accomplished in Accordance With Previous Service 
Information

    (h) Accomplishing the actions required in paragraph (g) of this 
AD before the effective date of this AD in accordance with Boeing 
Alert Service Bulletin 747-25A3588, dated July 19, 2010, is 
considered acceptable for compliance with the corresponding actions 
specified in this AD.

Alternative Methods of Compliance (AMOCs)

    (i)(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. In accordance with 14 
CFR 39.19, send your request to your principal inspector or local 
Flight Standards District Office, as appropriate. If sending 
information directly to the manager of the ACO, send it to the 
attention of the person identified in the Related Information 
section of this AD. Information may be e-mailed to: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

Related Information

    (j) For more information about this AD, contact Francis Smith, 
Aerospace Engineer, Cabin Safety & Environmental Systems Branch, 
ANM-150S, FAA, Seattle Aircraft Certification Office (ACO), 1601 
Lind Avenue, SW., Renton, Washington 98057-3356; phone: 425-917-6596 
; fax: 425-917-6590; e-mail: Francis.Smith@faa.gov.

Material Incorporated by Reference

    (k) You must use Boeing Alert Service Bulletin 747-25A3588, 
Revision 1, dated April 7, 2011, 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; phone: 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 July 26, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-19828 Filed 8-4-11; 8:45 am]
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