
[Federal Register Volume 81, Number 168 (Tuesday, August 30, 2016)]
[Proposed Rules]
[Pages 59544-59546]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-20667]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-9053; Directorate Identifier 2016-NM-075-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
The Boeing Company Model 747-8 and 747-8F series airplanes. This 
proposed AD was prompted by reports of damaged vapor seals, block 
seals, and heat shield seals on the outboard pylons between the engine 
strut and aft fairing. This proposed AD would require repetitive 
inspections for heat damage of the vapor seals between the engine strut 
and aft fairing, and replacement of the seals with new seals if 
necessary. We are proposing this AD to detect and correct heat damage 
to the vapor seals between the engine strut and aft fairing. Such 
damage could allow flammable fluid leakage into the aft fairing, which 
could result in an uncontrolled fire in the engine strut.

DATES: We must receive comments on this proposed AD by October 14, 
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: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this NPRM, 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. It 
is also available on the internet at http://www.regulations.gov by 
searching for and locating Docket No. FAA-2016-9053.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-
9053; 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: Sue Lucier, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office 
(ACO), 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-
6438; fax: 425-917-6590; email: suzanne.lucier@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2016-9053; 
Directorate Identifier 2016-NM-075-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 have received reports of damaged vapor seals, block seals, and 
heat shield seals on the outboard pylons between the aft fairing and 
engine strut on the number 1 and number 4 engines. The reports indicate 
that vapor seal damage occurring on the outboard pylons at 1,468 flight 
cycles, fully compromised the vapor seals at 2,768 flight cycles and 
3,626 flight cycles. It was determined that this condition affects only 
the outboard pylons because the vapor seal is located directly above 
the heat shield seal in these pylons. Heat from the exhaust nozzle to 
the vapor seal damages the seal and degrades the sealing quality. The 
vapor seal is a safety feature that is designed to isolate flammable 
hydraulic fluid from an ignition source. If the vapor seal has heat 
damage and there is a hydraulic leak that sprays onto the strut 
bulkhead, fluid could drain across the worn seal and contact heat 
shield surfaces below the seals. Flammable fluid leakage into the aft 
fairing could result in an uncontrolled fire in the engine strut.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 747-54A2246, dated 
February 5, 2016. The service information describes procedures for 
repetitive inspections for heat damage of the vapor seals between the 
engine strut and aft fairing, and replacement of the seals with new 
seals. 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 AD 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.

Proposed AD Requirements

    This proposed AD would require accomplishing the actions specified 
in the service information described previously, except as discussed 
under ``Difference Between this Proposed AD and the Service 
Information.'' For information on the procedures and compliance times, 
see this service information at http://www.regulations.gov by searching 
for and locating Docket No. FAA-2016-9053.

Difference Between This Proposed AD and the Service Information

    Boeing Alert Service Bulletin 747-54A2246, dated February 5, 2016, 
recommends accomplishment of Part 4, ``Structural Inspection and Repair 
for Heat Damage'' (economic related), during accomplishment of Part 3, 
``Seal Replacement'' (safety related), before installation of new 
seals. Part 4 is included as an economic consideration to prevent 
possible operational

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disruptions. However, this NPRM would not require those structural 
inspections.

Interim Action

    We consider this proposed AD interim action. The manufacturer is 
currently developing a modification that will address the unsafe 
condition identified in this proposed AD. Once this modification is 
developed, approved, and available, we might consider additional 
rulemaking.

Costs of Compliance

    We estimate that this proposed AD affects 10 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
----------------------------------------------------------------------------------------------------------------
Vapor seal inspections.........  4 work-hours X $85 per               $0  $340 per            $3,400 per
                                  hour = $340 per                          inspection cycle.   inspection cycle
                                  inspection cycle.
----------------------------------------------------------------------------------------------------------------

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

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                   Action                                 Labor cost                Parts cost        product
----------------------------------------------------------------------------------------------------------------
Seal replacement...........................  132 work-hours x $85 per hour =                  $0         $11,220
                                              $11,220.
----------------------------------------------------------------------------------------------------------------

    According to the manufacturer, some of the costs of this proposed 
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

    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, 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-2016-9053; Directorate Identifier 
2016-NM-075-AD.

(a) Comments Due Date

    We must receive comments by October 14, 2016.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 747-8 and 747-8F 
series airplanes, certificated in any category.

(d) Subject

    Air Transport Association (ATA) of America Code 54 Nacelles/
pylons.

(e) Unsafe Condition

    This AD was prompted by reports of damaged vapor seals, block 
seals, and heat shield seals on the outboard pylons between the 
engine strut and aft fairing. We are issuing this AD to detect and 
correct heat damage to the vapor seals between the engine strut and 
aft fairing. Such damage could allow flammable fluid leakage into 
the aft fairing, which could result in an uncontrolled fire in the 
engine strut.

(f) Compliance

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

(g) Repetitive Inspections

    At the later of the times specified in paragraphs (g)(1) and 
(g)(2) of this AD: Do a detailed inspection for heat damage of the

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vapor seals on the outboard pylons between the strut and aft fairing 
of the numbers 1 and 4 engines, in accordance with Part 2 of the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
54A2246, dated February 5, 2016. Repeat the inspection thereafter at 
intervals not to exceed 1,200 flight cycles.
    (i) Before the accumulation of 1,800 total flight cycles, or 
within 1,800 flight cycles after the most recent vapor seal, block 
seal, and heat shield seal replacement, whichever is later.
    (ii) Within 6 months after the effective date of this AD.

(h) Replacement

    If during any inspection required by paragraph (g) of this AD 
any heat damage of any vapor seal is found: Before further flight, 
replace the vapor seal, heat shield seal, and block seal with new 
seals, in accordance with Part 3 of the Accomplishment Instructions 
of Boeing Alert Service Bulletin 747-54A2246, dated February 5, 
2016. Repeat the inspection required by paragraph (g) of this AD 
within 1,800 flight cycles after doing the replacement, and 
thereafter at intervals not to exceed 1,200 flight cycles.

(i) 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 (j)(1) of this AD. 
Information may be emailed 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.
    (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.
    (4) For service information that contains steps that are labeled 
as Required for Compliance (RC), the provisions of paragraphs 
(i)(4)(i) and (i)(4)(ii) apply.
    (i) The steps labeled as RC, including substeps under an RC step 
and any figures identified in an RC step, must be done to comply 
with the AD. An AMOC is required for any deviations to RC steps, 
including substeps and identified figures.
    (ii) Steps not labeled as RC may be deviated from using accepted 
methods in accordance with the operator's maintenance or inspection 
program without obtaining approval of an AMOC, provided the RC 
steps, including substeps and identified figures, can still be done 
as specified, and the airplane can be put back in an airworthy 
condition.

(j) Related Information

    (1) For more information about this AD, contact Sue Lucier, 
Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle ACO, 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6438; 
fax: 425-917-6590; email: suzanne.lucier@faa.gov.
    (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; 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.

    Issued in Renton, Washington, on August 19, 2016.
Dorr M. Anderson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-20667 Filed 8-29-16; 8:45 am]
 BILLING CODE 4910-13-P


