AD 2014-13-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Learjet Inc. | 45 | Airworthiness Directives; Learjet Inc. Airplanes |
Unsafe Condition
Premature corrosion found on the structural support flange for the engine thrust reverser, which could lead to failure of the thrust reverser structural support and subsequent departure of the thrust reverser from the engine.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect metallic components of the thrust reverser's attach flange for corrosion using fluorescent penetrant inspection. Inspect the thrust reverser flange for damage to the sealant. Install sealants and gaskets as applicable to the thrust reverser flanges and service island flanges. Perform related investigative and corrective actions as necessary.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the compliance times specified in the AD, unless already done.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Learjet Inc. Model 45 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 certain Learjet Inc. Model 45 airplanes. This AD was prompted by a report of two cases of premature corrosion found on the structural support flange for the engine thrust reverser. This AD requires inspecting for any corrosion, and damage to the sealant; installing sealants and gaskets; and related investigative and corrective actions as necessary. We are issuing this AD to prevent failure of the thrust reverser structural support, which could result in departure of the thrust reverser from the engine that could subsequently result in damage to the adjacent support structure and engine controls, airframe structure, and control surfaces. Departing thrust reversers could also result in injury to persons on the ground.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This AD applies to Learjet Inc. Model 45 airplanes having serial
numbers (S/Ns) 45-005 through 45-436 inclusive, and 45-2001 through
45-2132 inclusive, certificated in any category, that are equipped
with composite engine fan bypass ducts.
Note 1 to paragraph (c) of this AD: Learjet Model 45 airplanes
having S/Ns 45-2001 and subsequent are commonly referred to as
``Model 40'' airplanes or Learjet 40 airplanes as marketing
designations.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 79, Number 135 (Tuesday, July 15, 2014)]
[Rules and Regulations]
[Pages 41085-41087]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2014-15377]
========================================================================
Rules and Regulations
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains regulatory documents
having general applicability and legal effect, most of which are keyed
to and codified in the Code of Federal Regulations, which is published
under 50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by the Superintendent of Documents.
Prices of new books are listed in the first FEDERAL REGISTER issue of each
week.
========================================================================
Federal Register / Vol. 79, No. 135 / Tuesday, July 15, 2014 / Rules
and Regulations
[[Page 41085]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2014-0010; Directorate Identifier 2012-NM-218-AD;
Amendment 39-17882; AD 2014-13-06]
RIN 2120-AA64
Airworthiness Directives; Learjet Inc. Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Learjet Inc. Model 45 airplanes. This AD was prompted by a report of
two cases of premature corrosion found on the structural support flange
for the engine thrust reverser. This AD requires inspecting for any
corrosion, and damage to the sealant; installing sealants and gaskets;
and related investigative and corrective actions as necessary. We are
issuing this AD to prevent failure of the thrust reverser structural
support, which could result in departure of the thrust reverser from
the engine that could subsequently result in damage to the adjacent
support structure and engine controls, airframe structure, and control
surfaces. Departing thrust reversers could also result in injury to
persons on the ground.
DATES: This AD is effective August 19, 2014.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of August 19,
2014.
ADDRESSES: For service information identified in this AD, contact
Learjet, Inc., One Learjet Way, Wichita, KS 67209-2942; telephone 316-
946-2000; fax 316-946-2220; email <a href="/cdn-cgi/l/email-protection#badbd994d3d9cefadbdfc8d594d8d5d7d8dbc8ded3dfc894d9d5d7"><span class="__cf_email__" data-cfemail="39585a17505a4d79585c4b56175b56545b584b5d505c4b175a5654">[email protected]</span></a>; Internet
<a href="http://www.bombardier.com">http://www.bombardier.com</a>. You may view this referenced service
information at the FAA, Transport Airplane Directorate; 1601 Lind
Avenue SW., Renton, WA 98057-3356. 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> by searching for and locating Docket No. FAA-2014-
0010; 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 Docket 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: Paul Chapman, Aerospace Engineer,
Airframe and Services Branch, ACE-118W, FAA, Wichita Aircraft
Certification Office, 1801 Airport Road, Room 100, Mid-Continent
Airport, Wichita, KS 67209; phone: 316-946-4152; fax: 316-946-4107;
email: <a href="/cdn-cgi/l/email-protection#aedecfdbc280cdc6cfdec3cfc0eec8cfcf80c9c1d8"><span class="__cf_email__" data-cfemail="ea9a8b9f86c489828b9a878b84aa8c8b8bc48d859c">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 by adding an AD that would apply to certain Learjet Inc. Model
45 airplanes. The NPRM published in the Federal Register on February
10, 2014 (79 FR 7601). The NPRM was prompted by a report of two cases
of premature corrosion found on the structural support flange for the
engine thrust reverser that attaches the thrust reverser to the engine.
The thrust reverser's attach flange is made of aluminum and the
corrosion of that flange can be caused by contact with exposed graphite
fibers from the engine's composite bypass duct. The NPRM proposed to
require doing a fluorescent penetrant inspection of the metallic
components of the thrust reverser's attach flange for any corrosion;
inspecting the thrust reverser flange for damage to the sealant, as
applicable; installing sealants and gaskets, as applicable, to the
thrust reverser flanges and service island flanges; and related
investigative and corrective actions as necessary. We are issuing this
AD to prevent failure of the thrust reverser structural support, which
could result in departure of the thrust reverser from the engine that
could subsequently result in damage to the adjacent support structure
and engine controls, airframe structure, and control surfaces.
Departing thrust reversers could also result in injury to persons on
the ground.
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 Add Service Information to Paragraph (i) of This AD
Bombardier requested that paragraph (i) of the proposed AD (79 FR
1601, February 10, 2014) be revised to add Bombardier Service Bulletin
40-78-03, Revision 1, dated November 5, 2012; or Bombardier Service
Bulletin 45-78-9, Revision 1, dated November 5, 2012. Bombardier stated
that adding this service information to paragraph (i) of the proposed
AD would allow credit for accomplishing the requirements of paragraph
(g) of the proposed AD before the effective date of the AD.
We disagree with revising paragraph (i) of this AD. The purpose of
paragraph (i) of this AD is to allow credit for using an earlier
revision of the required service information before the effective date
of the AD if that earlier revision is considered acceptable for
addressing the unsafe condition. If actions required by paragraph (g)
of this AD were accomplished before the effective date of the AD, using
the service information required by paragraph (g) of this AD, those
actions are considered acceptable for compliance, since paragraph (f)
of this AD states ``Comply with this AD within the compliance times
specified, unless already done.'' We have not changed this AD in this
regard.
Clarification of Marketing Designation
We have revised Note 1 to paragraph (c) of this AD to clarify the
marketing designations that Model 45 airplanes might be known as.
[[Page 41086]]
Conclusion
We reviewed the relevant data, considered the comment received, and
determined that air safety and the public interest require adopting
this AD as proposed except for minor editorial changes. We have
determined that these minor changes:
<bullet> Are consistent with the intent that was proposed in the
NPRM (79 FR 1601, February 10, 2014) for correcting the unsafe
condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM (79 FR 1601, February 10, 2014).
Costs of Compliance
We estimate that this AD affects 365 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:
Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Number of U.S. Cost on U.S.
Action Labor cost Parts cost Cost per product products operators
--------------------------------------------------------------------------------------------------------------------------------------------------------
Inspections and installing Between 26 and 36 work- Between $1,216 and Between $3,426 and 730 thrust reversers Between $2,500,980
sealants and gaskets. hours x $85 per hour = $1,476 per thrust $4,536 per thrust (365 airplanes). and $3,311,280.
Between $2,210 and $3,060 reverser. reverser.
per thrust reverser.
--------------------------------------------------------------------------------------------------------------------------------------------------------
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 this
replacement.
On-Condition Costs
----------------------------------------------------------------------------------------------------------------
Action Labor cost Parts cost Cost per product
----------------------------------------------------------------------------------------------------------------
Replacing thrust reverser 40 work-hours x $85 $1,200 per thrust $4,600 per thrust reverser.
attachment flange. per hour = $3,400 per reverser.
thrust reverser.
----------------------------------------------------------------------------------------------------------------
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):
2014-13-06 Learjet Inc.: Amendment 39-17882; Docket No. FAA-2014-
0010; Directorate Identifier 2012-NM-218-AD.
(a) Effective Date
This AD is effective August 19, 2014.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Learjet Inc. Model 45 airplanes having serial
numbers (S/Ns) 45-005 through 45-436 inclusive, and 45-2001 through
45-2132 inclusive, certificated in any category, that are equipped
with composite engine fan bypass ducts.
Note 1 to paragraph (c) of this AD: Learjet Model 45 airplanes
having S/Ns 45-2001 and subsequent are commonly referred to as
``Model 40'' airplanes or Learjet 40 airplanes as marketing
designations.
(d) Subject
Air Transport Association (ATA) of America Code 78, Engine
Exhaust.
(e) Unsafe Condition
This AD was prompted by a report of two cases of premature
corrosion found on the structural support flange for the engine
thrust reverser. We are issuing this AD to prevent failure of the
thrust reverser structural support, which could result in departure
of the thrust reverser from the engine that could subsequently
result in damage to the adjacent support structure and engine
controls, airframe structure, and control surfaces.
[[Page 41087]]
Departing thrust reversers could also result in injury to persons on
the ground.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Inspections and Sealant Installation With Applicable Related
Investigative and Corrective Actions
Within 1,200 flight hours or 48 months after the effective date
of this AD, whichever occurs first, do the requirements of paragraph
(g)(1) of this AD; and for the airplanes identified in paragraph
(g)(2) of this AD, do the requirements of paragraph (g)(2) of this
AD concurrently.
(1) Do a detailed inspection of the thrust reverser flange for
damage to the sealant, as applicable, and install sealants and
gaskets before further flight, as applicable, to the thrust reverser
flanges and service island flanges, in accordance with the
Accomplishment Instructions of Bombardier Service Bulletin 40-78-03,
Revision 1, dated November 5, 2012 (for Model 45 airplanes having S/
Ns 45-2001 through 45-2132 inclusive); or Bombardier Service
Bulletin 45-78-9, Revision 1, dated November 5, 2012 (for Model 45
airplanes having S/Ns 45-005 through 45-436 inclusive).
(2) For Model 45 airplanes having S/Ns 45-2001 through 45-2129
inclusive and S/Ns 45-005 through 45-420 inclusive: Do a fluorescent
penetrant inspection for corrosion of the metallic components of the
thrust reverser's attach flange for any corrosion, and all
applicable related investigative and corrective actions, in
accordance with the Accomplishment Instructions of Nordam Service
Bulletin 5045 78-13, dated January 17, 2012, except as required by
paragraph (h) of this AD. Do all applicable related investigative
and corrective actions before further flight.
(h) Exception to the Nordam Service Information
If any material thickness less than the minimum allowable
thickness is found during any inspection required by paragraph
(g)(2) of this AD, and Nordam Service Bulletin 5045 78-13, dated
January 17, 2012, specifies contacting Bombardier Learjet for
appropriate action: Before further flight, repair the thrust
reverser's attach flange in accordance with a method approved by the
Manager, Wichita Aircraft Certification Office (ACO), FAA. For a
repair method to be approved by the Manager, Wichita ACO, as
required by this paragraph, the Manager's approval letter must
specifically refer to this AD.
(i) Credit for Previous Actions
This paragraph provides credit for the actions specified in
paragraph (g) of this AD, if those actions were performed before the
effective date of this AD using Bombardier Service Bulletin 40-78-
03, dated February 27, 2012 (for Model 45 airplanes having S/Ns 45-
2001 through 45-2132); or Bombardier Service Bulletin 45-78-9, dated
February 27, 2012 (for Model 45 airplanes having S/Ns 45-005 through
45-436).
(j) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Wichita 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.
(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.
(k) Related Information
(1) For more information about this AD, contact Paul Chapman,
Aerospace Engineer, Airframe and Services Branch, ACE-118W, FAA,
Wichita Aircraft Certification Office, 1801 Airport Road, Room 100,
Mid-Continent Airport, Wichita, KS 67209; phone: 316-946-4152; fax:
316-946-4107; email: <a href="/cdn-cgi/l/email-protection#275746524b09444f46574a46496741464609404851"><span class="__cf_email__" data-cfemail="9dedfce8f1b3fef5fcedf0fcf3ddfbfcfcb3faf2eb">[email protected]</span></a>.
(2) Service information identified in this AD that is not
incorporated by reference may be viewed at the addresses specified
in paragraphs (l)(3) and (l)(4) of this AD.
(l) 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) Bombardier Service Bulletin 40-78-03, Revision 1, dated
November 5, 2012.
(ii) Bombardier Service Bulletin 45-78-9, Revision 1, dated
November 5, 2012.
(iii) Nordam Service Bulletin 5045 78-13, dated January 17,
2012.
(3) For Learjet and Nordam service information identified in
this AD, contact Learjet, Inc., One Learjet Way, Wichita, KS 67209-
2942; telephone 316-946-2000; fax 316-946-2220; email
<a href="/cdn-cgi/l/email-protection#6504064b0c0611250400170a4b070a08070417010c00174b060a08"><span class="__cf_email__" data-cfemail="2b4a480542485f6b4a4e594405494446494a594f424e5905484446">[email protected]</span></a>; Internet <a href="http://www.bombardier.com">http://www.bombardier.com</a>.
(4) You may view this service information at FAA, Transport
Airplane Directorate, 1601 Lind Avenue SW., Renton, WA 98057-3356.
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 June 19, 2014.
Michael J. Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2014-15377 Filed 7-14-14; 8:45 am]
BILLING CODE 4910-13-P
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Retrieved: Apr 4, 2026
Rights: U.S. Government Public Domain
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