AD 2013-24-12

Recurring final rule

Airworthiness Directives; The Boeing Company Airplanes

AD Number
2013-24-12
Status
final_rule
Effective Date
Product Category
engine
Docket
Docket No. FAA-2013-0976
FR Citation
78 FR 71989
Technical illustration of an aircraft turbine engine assembly
Problem area Engine

Applicability

TypeManufacturerModelDetails
aircraft Boeing Various Airworthiness Directives; The Boeing Company Airplanes

Unsafe Condition

Cracking of the barrel nuts and bolts on each forward engine mount, which could result in reduced load capacity of the forward engine mount, and could result in separation of an engine under power from the airplane, and consequent loss of control of the airplane.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Conduct repetitive ultrasonic or dye penetrant inspections for cracking of the barrel nuts and bolts on each forward engine mount. Send inspection results and any cracked bolts and barrel nuts to the manufacturer. Take related investigative and corrective actions if necessary.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within the compliance times specified in Boeing Alert Service Bulletin 747-71A2329.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

The Boeing Company Model 747-8 and 747-8F series airplanes.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 747-8 and 747-8F series airplanes. This AD requires repetitive ultrasonic or dye penetrant inspections for cracking of the barrel nuts and bolts, as applicable, on each forward engine mount, and related investigative and corrective actions if necessary. This AD was prompted by a report of cracked barrel nuts found on a forward engine mount. We are issuing this AD to detect and correct cracked barrel nuts on a forward engine mount, which could result in reduced load capacity of the forward engine mount, and could result in separation of an engine under power from the airplane, and consequent loss of control of the airplane.

Applicability Source Text

Show captured applicability text from the source AD
(c) Applicability

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

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 78, Number 231 (Monday, December 2, 2013)]
[Rules and Regulations]
[Pages 71989-71992]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2013-28616]


=======================================================================
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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0976; Directorate Identifier 2013-NM-198-AD; 
Amendment 39-17686; AD 2013-24-12]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

SUMMARY: We are adopting a new airworthiness directive (AD) for all The 
Boeing Company Model 747-8 and 747-8F series airplanes. This AD 
requires repetitive ultrasonic or dye penetrant inspections for 
cracking of the barrel nuts and bolts, as applicable, on each forward 
engine mount, and related investigative and corrective actions if 
necessary. This AD was prompted by a report of cracked barrel nuts 
found on a forward engine mount. We are issuing this AD to detect and 
correct cracked barrel nuts on a forward engine mount, which could 
result in reduced load capacity of the forward engine mount, and could 
result in separation of an engine under power from the airplane, and 
consequent loss of control of the airplane.

DATES: This AD is effective December 17, 2013.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of December 17, 
2013.
    We must receive comments on this AD by January 16, 2014.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
    <bullet> Federal eRulemaking Portal: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the instructions for submitting comments.
    <bullet> Fax: 202-493-2251.
    <bullet> 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.
    <bullet> 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 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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>. 
You may view this 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 <a href="http://www.regulations.gov">http://www.regulations.gov</a>; 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 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: Bill Ashforth, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: (425) 917-6432; 
fax: (425) 917-6590; email: <a href="/cdn-cgi/l/email-protection#f89a919494d6998b909e978a8c90b89e9999d69f978e"><span class="__cf_email__" data-cfemail="e6848f8a8ac887958e808994928ea6808787c8818990">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION:

[[Page 71990]]

Discussion

    We received a report that during the replacement of the No. 2 
engine, an operator conducted a non-destructive test (NDT) inspection 
of the barrel nuts on the forward engine mount and found cracks on two 
of the four barrel nuts. The operator also discovered one cracked 
barrel nut on the No. 1 engine. Boeing did a NDT on the No. 2 engine of 
a flight test airplane and discovered two barrel nuts with cracks. The 
barrel nuts are located at the forward end of the strut box and are 
used to fasten the forward engine mount to the strut. A barrel nut with 
a crack on one side is still able to carry ultimate load. A crack on 
both sides of a barrel nut will cause complete failure of the barrel 
nut. Complete failure of two or more barrel nuts on the same forward 
engine mount reduces the load capacity of the forward engine mount and 
could result in separation of an engine from the airplane. Cracked 
barrel nuts on a forward engine mount, if not detected and corrected, 
could result in reduced load capacity of the forward engine mount, and 
could result in separation of an engine under power from the airplane, 
and consequent loss of control of the airplane.

Relevant Service Information

    We reviewed Boeing Alert Service Bulletin 747-71A2329, dated 
September 27, 2013. For information on the procedures and compliance 
times, see this service information at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by 
searching for Docket No. FAA-2013-0976.

FAA's Determination

    We are issuing 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.

AD Requirements

    This AD requires accomplishing the actions specified in the service 
information described previously. This AD also requires sending the 
inspection results and any cracked bolts and barrel nuts to the 
manufacturer. The root cause of the cracking has not been determined 
and inspection data from the fleet needs to be gathered and analyzed.
    The FAA worked in conjunction with industry, under the 
Airworthiness Directives Implementation Aviation Rulemaking Committee, 
to enhance the AD system. One enhancement was a new process for 
annotating which steps in the service information are required for 
compliance with an AD. Differentiating these steps from other tasks in 
the service information is expected to improve an owner's/operator's 
understanding of crucial AD requirements and help provide consistent 
judgment in AD compliance. The actions specified in the service 
information described previously include steps that are labeled as 
``RC'' (required for compliance) because these steps have a direct 
effect on detecting, preventing, resolving, or eliminating an 
identified unsafe condition.
    As noted in the specified service information, steps labeled as 
``RC'' must be done to comply with the AD. However, steps that are not 
labeled as ``RC'' are recommended. Those steps that are not labeled as 
``RC'' may be deviated from, done as part of other actions, or done 
using accepted methods different from those identified in the service 
information without obtaining approval of an alternative method of 
compliance (AMOC), provided the steps labeled as ``RC'' can be done and 
the airplane can be put back in a serviceable condition. Any 
substitutions or changes to steps labeled as ``RC'' will require 
approval of an AMOC.
    The phrase ``related investigative actions'' is used in this AD. 
``Related investigative actions'' are follow-on actions that (1) are 
related to the primary actions, and (2) further investigate the nature 
of any condition found. Related investigative actions in an AD could 
include, for example, inspections.
    In addition, the phrase ``corrective actions'' is used in this AD. 
``Corrective actions'' are actions that correct or address any 
condition found. Corrective actions in an AD could include, for 
example, repairs.

Interim Action

    This AD is considered to be interim action. The inspection reports 
and return of cracked parts that are required by this AD will enable 
the manufacturer to obtain better insight into the nature, cause, and 
extent of the cracking, and eventually to develop final action to 
address the unsafe condition. Once final action has been identified, we 
might consider further rulemaking.

FAA's Justification and Determination of the Effective Date

    An unsafe condition exists that requires the immediate adoption of 
this AD. The FAA has found that the risk to the flying public justifies 
waiving notice and comment prior to adoption of this rule because 
cracked barrel nuts on a forward engine mount could result in reduced 
load capacity of the forward engine mount, and could result in 
separation of an engine under power from the airplane and consequent 
loss of the control of the airplane. Therefore, we find that notice and 
opportunity for prior public comment are impracticable and that good 
cause exists for making this amendment effective in less than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety and was not preceded by notice and an opportunity for public 
comment. However, we invite you to send any written data, views, or 
arguments about this AD. Send your comments to an address listed under 
the ADDRESSES section. Include the docket number FAA-2013-0976 and 
Directorate Identifier 2013-NM-198-AD at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this AD. We will 
consider all comments received by the closing date and may amend this 
AD because of those comments.
    We will post all comments we receive, without change, to <a href="http://www.regulations.gov">http://www.regulations.gov</a>, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this AD.

Costs of Compliance

    We estimate that this AD affects 8 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                  Cost on U.S.
             Action                    Labor cost            Parts cost     Cost  per product      operators
----------------------------------------------------------------------------------------------------------------
Inspections....................  Up to 24 work-hours x   None.............  Up to $2,040 per   Up to $16,320 per
                                  $85 per hour = $2,040                      inspection cycle.  inspection
                                  per inspection cycle.                                         cycle.
----------------------------------------------------------------------------------------------------------------


[[Page 71991]]

    We estimate the following costs to do any necessary replacements 
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 
replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
               Action                         Labor cost                Parts cost           Cost per product
----------------------------------------------------------------------------------------------------------------
Replacement of barrel nuts and       16 x $85 per hour = $1,360.  Up to $480............  Up to $1,840.
 bolts.
----------------------------------------------------------------------------------------------------------------

    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.

Paperwork Reduction Act

    A federal agency may not conduct or sponsor, and a person is not 
required to respond to, nor shall a person be subject to penalty for 
failure to comply with a collection of information subject to the 
requirements of the Paperwork Reduction Act unless that collection of 
information displays a current valid OMB control number. The control 
number for the collection of information required by this AD is 2120-
0056. The paperwork cost associated with this AD has been detailed in 
the Costs of Compliance section of this document and includes time for 
reviewing instructions, as well as completing and reviewing the 
collection of information. Therefore, all reporting associated with 
this AD is mandatory. Comments concerning the accuracy of this burden 
and suggestions for reducing the burden should be directed to the FAA 
at 800 Independence Ave. SW., Washington, DC 20591. ATTN: Information 
Collection Clearance Officer, AES-200.

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):

2013-24-12 The Boeing Company: Amendment 39-17686; Docket No. FAA-
2013-0976; Directorate Identifier 2013-NM-198-AD.

(a) Effective Date

    This AD is effective December 17, 2013.

(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

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 71, Powerplant.

(e) Unsafe Condition

    This AD was prompted by a report of cracked barrel nuts found on 
a forward engine mount. We are issuing this AD to detect and correct 
cracked barrel nuts on a forward engine mount, which could result in 
reduced load capacity of the forward engine mount, and could result 
in separation of an engine under power from the airplane, and 
consequent loss of control of the airplane.

(f) Compliance

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

(g) Repetitive Inspections and Corrective Actions

    Except as required by paragraph (h)(1) of this AD, at the time 
specified in paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 747-71A2329, dated September 27, 2013: Do the inspection 
specified in paragraph (g)(1) or (g)(2) of this AD, and do all 
applicable related investigative and corrective actions, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 747-71A2329, dated September 27, 2013. Do all 
applicable related investigative and corrective actions before 
further flight. Repeat the inspection thereafter at the times 
specified in paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 747-71A2329, dated September 27, 2013.
    (1) Ultrasonic inspection for cracking of the barrel nuts on 
each forward engine mount, except as required by paragraph (h)(2) of 
this AD.
    (2) Dye penetrant inspection for cracking of the bolts and 
barrel nuts. Whenever a dye penetrant inspection is done, all the 
bolts and barrel nuts on that engine mount must be removed and 
replaced with new or serviceable parts.

(h) Exceptions to Service Information Specifications

    (1) Where Boeing Alert Service Bulletin 747-71A2329, dated 
September 27, 2013, specifies a compliance time ``after the original 
issue date of this service bulletin,'' this AD requires compliance 
within the specified compliance time after the effective date of 
this AD.

[[Page 71992]]

    (2) Where Appendix B of Boeing Alert Service Bulletin 747-
71A2329, dated September 27, 2013, states alternate instruments and 
transducers can be used, this AD requires that only equivalent 
instruments and transducers can be used.
    (3) Where Appendix A of Boeing Alert Service Bulletin 747-
71A2329, dated September 27, 2013, states to record flight hours and 
flight cycles, record the flight hours and flight cycles on the 
airplane and the flight hours and flight cycles for each engine 
since change or removal.

(i) Reporting and Sending Parts

    After any inspection required by paragraph (g) of this AD: 
Submit a report of the inspection results (both positive and 
negative), and return all cracked bolts and barrel nuts, at the 
applicable time specified in paragraph (i)(1) or (i)(2) of this AD. 
The report must include the information requested in Appendix A of 
Boeing Alert Service Bulletin 747-71A2329, dated September 27, 2013, 
except as required by paragraph (h)(3) of this AD. Both the report 
and all cracked bolts and barrel nuts must be sent to the address 
specified in Appendix A of Boeing Alert Service Bulletin 747-
71A2329, dated September 27, 2013.
    (1) For airplanes on which an ultrasonic inspection was done and 
no cracking was found, do the required actions at the time specified 
in paragraph (i)(1)(i) or (i)(1)(ii) of this AD, as applicable.
    (i) If the inspection was done on or after the effective date of 
this AD: Submit the report within 10 days after the inspection.
    (ii) If the inspection was done before the effective date of 
this AD: Submit the report within 10 days after the effective date 
of this AD.
    (2) For airplanes on which a dye penetrant inspection was done, 
do the required actions at the time specified in paragraph (i)(2)(i) 
or (i)(2)(ii) of this AD, as applicable.
    (i) If the inspection was done on or after the effective date of 
this AD: Submit the report and return all cracked bolts and barrel 
nuts within 10 days after replacing the bolts and barrel nuts with 
new or serviceable bolt and barrel nuts in accordance with Part 2 of 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
747-71A2329, dated September 27, 2013.
    (ii) If the inspection was done before the effective date of 
this AD: Submit the report and return all cracked bolts and barrel 
nuts within 10 days after the effective date of this AD.

(j) Paperwork Reduction Act Burden Statement

    A federal agency may not conduct or sponsor, and a person is not 
required to respond to, nor shall a person be subject to a penalty 
for failure to comply with a collection of information subject to 
the requirements of the Paperwork Reduction Act unless that 
collection of information displays a current valid OMB Control 
Number. The OMB Control Number for this information collection is 
2120-0056. Public reporting for this collection of information is 
estimated to be approximately 5 minutes per response, including the 
time for reviewing instructions, completing and reviewing the 
collection of information. All responses to this collection of 
information are mandatory. Comments concerning the accuracy of this 
burden and suggestions for reducing the burden should be directed to 
the FAA at: 800 Independence Ave. SW., Washington, DC 20591, Attn: 
Information Collection Clearance Officer, AES-200.

(k) 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 (l) of this AD. 
Information may be emailed to: <a href="/cdn-cgi/l/email-protection#182135595655354b7d796c6c747d35595b57355955575b354a7d696d7d6b6c6b587e7979367f776e"><span class="__cf_email__" data-cfemail="21180c606f6c0c72444055554d440c60626e0c606c6e620c7344505444525552614740400f464e57">[email&#160;protected]</span></a>.
    (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 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. 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.
    (4) If the service information contains steps that are labeled 
as ``RC'' (Required for Compliance), those steps must be done to 
comply with this AD; any steps that are not labeled as ``RC'' are 
recommended. Those steps that are not labeled as ``RC'' may be 
deviated from, done as part of other actions, or done using accepted 
methods different from those identified in the specified service 
information without obtaining approval of an AMOC, provided the 
steps labeled as ``RC'' can be done and the airplane can be put back 
in a serviceable condition. Any substitutions or changes to steps 
labeled as ``RC'' require approval of an AMOC.

(l) Related Information

    For more information about this AD, contact Bill Ashforth, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; 
phone: (425) 917-6432; fax: (425) 917-6590; email: 
<a href="/cdn-cgi/l/email-protection#caa8a3a6a6e4abb9a2aca5b8bea28aacababe4ada5bc"><span class="__cf_email__" data-cfemail="77151e1b1b5916041f111805031f3711161659101801">[email&#160;protected]</span></a>.

(m) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Boeing Alert Service Bulletin 747-71A2329, dated September 
27, 2013.
    (ii) Reserved.
    (3) 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 <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
    (4) You may view this service information at 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.
    (5) You may view this 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: <a href="http://www.archives.gov/federal-register/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.

    Issued in Renton, Washington, on November 19, 2013.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-28616 Filed 11-29-13; 8:45 am]
BILLING CODE 4910-13-P

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