[Federal Register Volume 79, Number 27 (Monday, February 10, 2014)]
[Proposed Rules]
[Pages 7601-7603]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2014-02715]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2014-0010; Directorate Identifier 2012-NM-218-AD]
RIN 2120-AA64
Airworthiness Directives; Learjet Inc. 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
certain Learjet Inc. Model 45 airplanes. This proposed AD was prompted
by a report of two cases of premature corrosion found on the structural
support flange for the engine thrust reverser. This proposed AD would
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 proposing
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: We must receive comments on this proposed AD by March 27, 2014.
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 proposed AD, contact
Learjet, Inc., One Learjet Way, Wichita, KS 67209-2942; telephone 316-
946-2000; fax 316-946-2220; email [email protected]; Internet
http://www.bombardier.com. 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 http://www.regulations.gov 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 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: 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: [email protected].
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-2014-0010;
Directorate Identifier 2012-NM-218-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 received 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. This condition, if not corrected, could result
in 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.
Relevant Service Information
We reviewed Bombardier Service Bulletin 40-78-03, Revision 1, dated
[[Page 7602]]
November 5, 2012 (for Model 45 airplanes having S/N 45-2001 through 45-
2132); and Bombardier Service Bulletin 45-78-9, Revision 1, dated
November 5, 2012 (for Model 45 airplanes having S/N 45-005 through 45-
436). Those service bulletins describe inspecting the thrust reverser's
attach flange for damage to the sealant, as applicable, and installing
sealants and gaskets as applicable to the thrust reverser flanges and
service island flanges.
We also reviewed Nordam Service Bulletin 5045 78-13, dated January
17, 2012 (for Model 45 airplanes having S/N 45-005 through 45-420
inclusive and S/N 45-2001 through 45-2129 inclusive), which describes
procedures for fluorescent penetrant inspection of the metallic
components of the thrust reverser's attach flange for any corrosion,
and related investigative and corrective actions. Corrective actions
include removing corrosion from the thrust reverser's attach flange,
applying finishes, contacting the manufacturer, and replacing the
engine attach flange. Related investigative actions include doing
further fluorescent penetrant inspection for any remaining corrosion,
and measuring to ensure a minimum material thickness.
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 the Proposed AD and the Service
Information.''
Difference Between Proposed AD and the Service Information
Although Nordam Service Bulletin 5045 78-13, dated January 17,
2012, specifies that operators may contact the manufacturer for
disposition of certain repair conditions, this proposed AD would
require operators to repair those conditions in accordance with a
method approved by the FAA.
Costs of Compliance
We estimate that this proposed AD affects 365 airplanes of U.S.
registry.
We estimate the following costs to comply with this proposed AD:
Estimated Costs
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Number of U.S. Cost on U.S.
Action Labor cost Parts cost Cost per product products operators
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Inspections and installing sealants Between 26 and 36 work- Between $1,216 and Between $3,426 and 730 thrust reversers Between $2,500,980
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 reverser. reverser.
$3,060 per thrust
reverser.
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We estimate the following costs to do any necessary replacements
that would be required based on the results of the proposed inspection.
We have no way of determining the number of aircraft that might need
this replacement.
On-Condition Costs
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Action Labor cost Parts cost Cost per product
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Replacing thrust reverser attachment 40 work-hours x $85 per $1,200 per thrust $4,600 per thrust
flange. hour = $3,400 per reverser. reverser.
thrust reverser.
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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:
[[Page 7603]]
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):
Learjet Inc.: Docket No. FAA-2014-0010; Directorate Identifier 2012-
NM-218-AD.
(a) Comments Due Date
We must receive comments by March 27, 2014.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Learjet Inc. Model 45 airplanes having serial
numbers (S/N) 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 Lear 40 Model 45 airplanes as a marketing
designation.
(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. 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/
N 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/N 45-005 through 45-436 inclusive).
(2) For Model 45 airplanes having S/N 45-2001 through 45-2129
inclusive and S/N 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/N 45-
2001 through 45-2132); or Bombardier Service Bulletin 45-78-9, dated
February 27, 2012 (for Model 45 airplanes having S/N 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: [email protected].
(2) 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 [email protected];
Internet http://www.bombardier.com. 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.
Issued in Renton, Washington, on January 22, 2014.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2014-02715 Filed 2-7-14; 8:45 am]
BILLING CODE 4910-13-P