81 FR 12041 - Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 81, Issue 45 (March 8, 2016)

We are revising an earlier proposed airworthiness directive (AD) for certain 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. The notice of proposed rulemaking (NPRM) proposed to require replacing the wire bundles inside the electrical conduit of the forward and aft boost pumps of the numbers 1 and 4 main fuel tanks with new, improved wire bundles inserted into conduit liners. The NPRM was prompted by several reports of chafing of the wire bundles inside the electrical conduit of the forward and aft boost pumps of the numbers 1 and 4 main fuel tanks due to high vibration. These wire bundles can chafe through the wire sleeving into the insulation, exposing the wire conductors. This action revises the NPRM by adding a revision to the maintenance or inspection program, as applicable, to include critical design configuration control limitations (CDCCL) for the fuel boost pump wiring. We are proposing this SNPRM to prevent chafing of the wire bundles and subsequent arcing between the wiring and the electrical conduit creating an ignition source in the fuel tanks, which could result in a fire and consequent fuel tank explosion. Since these actions impose an additional burden over that proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes.

[Federal Register Volume 81, Number 45 (Tuesday, March 8, 2016)]
[Proposed Rules]
[Pages 12041-12044]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2016-04681]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-0935; Directorate Identifier 2014-NM-243-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (SNPRM); reopening 
of comment period.

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SUMMARY: We are revising an earlier proposed airworthiness directive 
(AD) for certain 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. The notice of proposed 
rulemaking (NPRM) proposed to require replacing the wire bundles inside 
the electrical conduit of the forward and aft boost pumps of the 
numbers 1 and 4 main fuel tanks with new, improved wire bundles 
inserted into conduit liners. The NPRM was prompted by several reports 
of chafing of the wire bundles inside the electrical conduit of the 
forward and aft boost pumps of the numbers 1 and 4 main fuel tanks due 
to high vibration. These wire bundles can chafe through the wire 
sleeving into the insulation, exposing the wire conductors. This action 
revises the NPRM by adding a revision to the maintenance or inspection 
program, as applicable, to include critical design configuration 
control limitations (CDCCL) for the fuel boost pump wiring. We are 
proposing this SNPRM to prevent chafing of the wire bundles and 
subsequent arcing between the wiring and the electrical conduit 
creating an ignition source in the fuel tanks, which could result in a 
fire and consequent fuel tank explosion. Since these actions impose an 
additional burden over that proposed in the NPRM, we are reopening the 
comment period to allow the public the chance to comment on these 
proposed changes.

DATES: We must receive comments on this SNPRM by April 22, 2016.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, 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 SNPRM, contact Boeing 
Commercial Airplanes, Attention: Data & Services Management, P. O. Box 
3707, MC 2H-65, Seattle, WA 98124-2207; telephone: 206-544-5000, 
extension 1; fax: 206-766-5680; Internet: https://www.myboeingfleet.com. You may view this referenced service information 
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., 
Renton, WA. For information on the availability of this material at the 
FAA, call 425-227-1221. Boeing Alert Service Bulletin 747-28A2306, 
dated October 2, 2014, is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-
0935.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://

[[Page 12042]]

www.regulations.gov by searching for and locating Docket No. FAA-2015-
0935; 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 (phone: 800-647-5527) is in the ADDRESSES section. Comments will 
be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Tung Tran, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-
6505; fax: 425-917-6590; email: [email protected].

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-2015-0935; 
Directorate Identifier 2014-NM-243-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 an NPRM to amend 14 CFR part 39 by adding an AD that 
would apply to certain 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. The NPRM published in the 
Federal Register on May 1, 2015 (80 FR 24850) (``the NPRM''). The NPRM 
proposed to require replacing the wire bundles inside the electrical 
conduit of the forward and aft boost pumps of the numbers 1 and 4 main 
fuel tanks with new, improved wire bundles inserted into conduit 
liners.

Actions Since the NPRM was Issued

    Since we issued the NPRM, we have determined that it is necessary 
to revise the NPRM by adding a revision to the maintenance or 
inspection program, as applicable, to include critical design 
configuration control limitations (CDCCL) for the fuel boost pump 
wiring.

Related AD

    AD 2011-15-03, Amendment 39-16750 (76 FR 41659, July 15, 2011) 
(``AD 2011-15-03''), superseded AD 97-26-07, Amendment 39-10250 (62 FR 
65352, December 12, 1997), and requires repetitive inspections to 
detect damage of the sleeving and wire bundles of the boost pumps of 
the numbers 1 and 4 main fuel tanks, and of the auxiliary tank jettison 
pumps (if installed); replacement of any damaged sleeving with new 
sleeving; and repair or replacement of any damaged wires with new 
wires. For airplanes on which any burned wires are found, AD 2011-15-03 
also requires an inspection to detect damage of the conduit, and 
replacement of any damaged conduit with a serviceable conduit. AD 2011-
15-03 reduced the initial compliance time and repetitive inspection 
interval in AD 97-26-07. AD 2011-15-03 was prompted by fleet 
information indicating that the repetitive inspection interval in AD 
97-26-07 was too long because excessive chafing of the sleeving 
continued to occur much earlier than expected between scheduled 
inspections. Accomplishing the replacement specified in this proposed 
AD would terminate the inspections required by paragraphs (g), (h), and 
(n) of AD 2011-15-03.

Comments

    We gave the public the opportunity to comment on the NPRM. The 
following presents the comments received on the NPRM and the FAA's 
response to each comment.

Support for the NPRM

    Boeing concurred with the contents of the NPRM.

Request To Withdraw the NPRM

    UPS recommended that we withdraw the NPRM so that UPS can continue 
doing the inspections required by AD 2011-15-03. UPS stated that it has 
been inspecting the forward and aft boost pump wire bundles and 
sleeving since 2007 per the requirements in AD 2011-15-03, and is 
satisfied with the current inspection, which detects signs of wear 
before major damage occurs. UPS added that the wire bundle replacement 
in this NPRM is a burden to the airlines, without adding safety to the 
boost pump or airplane fuel system.
    We do not agree with the commenter's request to withdraw the NPRM. 
We agree that the inspection required by AD 2011-15-03 is likely to 
detect signs of wear before major damage occurs, but the potential for 
an ignition source inside the fuel tank due to the single failure 
condition still exists. The manufacturer has now developed an improved 
wire bundle installation that eliminates the single failure condition. 
We have determined that installation of the improved design is required 
to eliminate the need for periodic maintenance and inspections in order 
to ensure safety.

Request To Change Paragraph (g) of the Proposed AD (in the NPRM)

    United Airlines (United) asked that paragraph (g) of the proposed 
AD (in the NPRM) be changed to add paragraphs (g), (h), (i), (j), and 
(k) of AD 2011-15-03, to the language which terminates the repetitive 
inspections required by paragraph (n) of AD 2011-15-03. United stated 
that those paragraphs are also terminated after doing the wire bundle 
replacement required by paragraph (g) of the proposed AD (in the NPRM).
    We agree to add paragraphs (g) and (h) of AD 2011-15-03, to the 
terminating action language specified in paragraph (g) of this proposed 
AD, because the replacement required by this proposed AD would 
terminate the inspections required by paragraphs (g) and (h) of AD 
2011-15-03. However, paragraphs (i), (j), and (k) of AD 2011-15-03 are 
on-condition corrective actions, which must be done depending on the 
findings during any inspection required by paragraph (g) or (h) of AD 
2011-15-03. Therefore, we have not referenced paragraphs (i), (j), and 
(k) of AD 2011-15-03 in paragraph (g) of this proposed AD.

Request To Add AWL Items

    United stated that incorporating airworthiness limitation (AWL) 
tasks 28-AWL-24 (747 CL Certification Maintenance Requirements) and 28-
AWL-35 (747-400 Maintenance Planning Data) should also be required by 
the NPRM.
    We agree that this proposed AD should include revising the 
maintenance or inspection program, as applicable, by incorporating the 
CDCCL tasks related to accomplishing Boeing Alert Service Bulletin 747-
28A2306, dated October 2, 2014; therefore, we have added new paragraphs 
(h) and (i) to this proposed AD to include those requirements. We have 
redesignated subsequent paragraphs accordingly.

[[Page 12043]]

Related Service Information Under 1 CFR Part 51

    We reviewed the following service information:
     Boeing Alert Service Bulletin 747-28A2306, dated October 
2, 2014. The service information describes procedures for replacing the 
wire bundles of the electrical conduit inside the electrical conduit of 
the forward and aft boost pumps of the numbers 1 and 4 main fuel tanks.
     AWL No. 28-AWL-24, ``Fuel Boost Pump Wires In Conduit 
Installation--In Fuel Tank,'' of Sub-section C.1, ``Fuel Tank Ignition 
Prevention,'' of Section C., ``Airworthiness Limitations--Systems,'' of 
the Boeing 747-100/200/300/SP Airworthiness Limitations (AWLs) and 
Certification Maintenance Requirements (CMRs) Document D6-13747-CMR, 
Revision June 2014. The service information describes a CDCCL for the 
fuel boost pump wiring.
     AWL No. 28-AWL-35, ``Fuel Boost Pump Wires In Conduit 
Installation--In Fuel Tank,'' of Sub-section B.1, ``Fuel System 
Ignition Prevention,'' of Section B, ``Airworthiness Limitations 
(AWLs)--Systems,'' of Section 9, Airworthiness Limitations (AWLs) and 
Certification Maintenance Requirements (CMRs), of Boeing 747-400 
Maintenance Planning Data (MPD) Document D621U400-9, Revision June 
2014. The service information describes a CDCCL for the fuel boost pump 
wiring.
    This service information is reasonably available because the 
interested parties have access to it through their normal course of 
business or by the means identified in the ADDRESSES section.

FAA's Determination

    We are proposing this SNPRM because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design. 
Certain changes described above expand the scope of the NPRM (80 FR 
24850, May 1, 2013). 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 SNPRM.

Proposed Requirements of This SNPRM

    This SNPRM would require accomplishing the actions specified in 
Boeing Alert Service Bulletin 747-28A2306, dated October 2, 2014, 
described previously. This SNPRM would also require revising the 
maintenance or inspection program, as applicable, to include CDCCLs for 
the fuel boost pump wiring.
    This AD requires revisions to certain operator maintenance 
documents to include new actions (e.g., inspections) and CDCCLs. 
Compliance with these actions and CDCCLs is required by 14 CFR 
91.403(c). For airplanes that have been previously modified, altered, 
or repaired in the areas addressed by this proposed AD, the operator 
may not be able to accomplish the actions 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 according to 
paragraph (j) of this AD. The request should include a description of 
changes to the required actions that will ensure the continued damage 
tolerance of the affected structure.
    Notwithstanding any other maintenance or operational requirements, 
components that have been identified as airworthy or installed on the 
affected airplanes before accomplishing the revision of the airplane 
maintenance or inspection program specified in this proposed AD do not 
need to be reworked in accordance with the CDCCLs. However, once the 
airplane maintenance or inspection program has been revised as required 
by this proposed AD, future maintenance actions on these components 
must be done in accordance with the CDCCLs.

Costs of Compliance

    We estimate that this proposed AD affects 176 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
----------------------------------------------------------------------------------------------------------------
Replacement......................  Up to 53                     $4,600  Up to $9,105.......  Up to $1,602,480.
                                    work[dash]hours x
                                    $85 per hour =
                                    $4,505.
Revise maintenance or inspection   1 work-hour x $85                 0  $85................  $14,960.
 program.                           per hour = $85.
----------------------------------------------------------------------------------------------------------------

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),
    (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.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator,

[[Page 12044]]

the FAA proposes to amend 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):

The Boeing Company: Docket No. FAA-2015-0935; Directorate Identifier 
2014-NM-243-AD.

(a) Comments Due Date

    We must receive comments by April 22, 2016.

(b) Affected ADs

    This AD affects AD 2011-15-03, Amendment 39-16750 (76 FR 41659, 
July 15, 2011).

(c) Applicability

    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 Alert Service Bulletin 747-
28A2306, dated October 2, 2014.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by several reports of chafing of the wire 
bundles inside the electrical conduit of the forward and aft boost 
pumps of the numbers 1 and 4 main fuel tanks due to high vibration. 
These wire bundles can chafe through the wire sleeving into the 
insulation, exposing the wire conductors. We are issuing this AD to 
prevent chafing of the wire bundles and subsequent arcing between 
the wiring and the electrical conduit creating an ignition source in 
the fuel tanks, which could result in a fire and consequent fuel 
tank explosion.

(f) Compliance

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

(g) Replacement

    Within 60 months after the effective date of this AD: Replace 
the wire bundles inside the electrical conduit of the forward and 
aft boost pumps of the numbers 1 and 4 main fuel tanks with new, 
improved wire bundles inserted into conduit liners, in accordance 
with the Accomplishment Instructions of Boeing Alert Service 
Bulletin 747-28A2306, dated October 2, 2014. Accomplishing the 
replacement required by this paragraph terminates the inspections 
required by paragraphs (g), (h), and (n) of AD 2011-15-03, Amendment 
39-16750 (76 FR 41659, July 15, 2011).

(h) Maintenance or Inspection Program Revision

    Within 180 days after the effective date of this AD, revise the 
maintenance or inspection program, as applicable, to incorporate 
critical design configuration control limitation (CDCCL) Task AWL 
No. 28-AWL-24, ``Fuel Boost Pump Wires In Conduit Installation--In 
Fuel Tank,'' of Sub-section C.1, ``Fuel Tank Ignition Prevention,'' 
of Section C., ``Airworthiness Limitations--Systems,'' of the Boeing 
747-100/200/300/SP Airworthiness Limitations (AWLs) and 
Certification Maintenance Requirements (CMRs) Document D6-13747-CMR, 
Revision June 2014; or CDCCL Task No. AWL No. 28-AWL-35, ``Fuel 
Boost Pump Wires In Conduit Installation--In Fuel Tank,'' of Sub-
section B.1, ``Fuel System Ignition Prevention,'' of Section B, 
``Airworthiness Limitations (AWLs)--Systems,'' of Section 9, 
Airworthiness Limitations (AWLs) and Certification Maintenance 
Requirements (CMRs), of Boeing 747-400 Maintenance Planning Data 
(MPD) Document D621U400-9, Revision June 2014; as applicable.

(i) No Alternative Actions, Intervals, and/or CDCCLs

    After accomplishing the revision required by paragraph (h) of 
this AD, no alternative actions (e.g., inspections), intervals, and/
or CDCCLs may be used unless the actions, intervals, and/or CDCCLs 
are approved as an alternative method of compliance (AMOC) in 
accordance with the procedures specified in paragraph (j) of this 
AD.

(j) Alternative Methods of Compliance (AMOCs)

    (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 paragraph (k)(1) of this AD. 
Information may be emailed to: [email protected].
    (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.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair, modification, or alteration required by this AD 
if it is approved by the Boeing Commercial Airplanes Organization 
Designation Authorization (ODA) that has been authorized by the 
Manager, Seattle ACO, to make those findings. To be approved, the 
repair method, modification deviation, or alteration deviation must 
meet the certification basis of the airplane, and the approval must 
specifically refer to this AD.

(k) Related Information

    (1) For more information about this AD, contact Tung Tran, 
Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle ACO, 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6505; 
fax: 425-917-6590; email: [email protected].
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; phone: 206-544-
5000, extension 1; fax: 206-766-5680; Internet: https://www.myboeingfleet.com. You may view this referenced service 
information at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue SW., Renton, WA. For information on the availability of this 
material at the FAA, call 425-227-1221.

    Issued in Renton, Washington, on February 18, 2016.
Dorr M. Anderson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-04681 Filed 3-7-16; 8:45 am]
 BILLING CODE 4910-13-P