80 FR 34258 - Airworthiness Directives; Learjet Inc. Airplanes

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 80, Issue 115 (June 16, 2015)

We are adopting a new airworthiness directive (AD) for certain Learjet Inc. Model 45 airplanes. This AD was prompted by reports of non-conforming windshield supports (coupe rails). This AD requires a general visual inspection of the coupe rails to detect gouging and scratches, and to determine if a radius has been removed; an ultrasound inspection to measure the dimensions of the lower coupe rails; an eddy current inspection to detect cracks of the lower coupe rails; replacement of the lower coupe rails if necessary; and revision of the maintenance or inspection program, as applicable. We are issuing this AD to detect and correct non-conforming windshield supports, which could result in uncontrolled cabin depressurization and compromise of the capability of the windshield to withstand a bird strike.

[Federal Register Volume 80, Number 115 (Tuesday, June 16, 2015)]
[Rules and Regulations]
[Pages 34258-34261]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2015-14396]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2014-0249; Directorate Identifier 2012-NM-211-AD; 
Amendment 39-18180; AD 2015-12-06]
RIN 2120-AA64


Airworthiness Directives; Learjet Inc. Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain 
Learjet Inc. Model 45 airplanes. This AD was prompted by reports of 
non-conforming windshield supports (coupe rails). This AD requires a 
general visual inspection of the coupe rails to detect gouging and 
scratches, and to determine if a radius has been removed; an ultrasound 
inspection to measure the dimensions of the lower coupe rails; an eddy 
current inspection to detect cracks of the lower coupe rails; 
replacement of

[[Page 34259]]

the lower coupe rails if necessary; and revision of the maintenance or 
inspection program, as applicable. We are issuing this AD to detect and 
correct non-conforming windshield supports, which could result in 
uncontrolled cabin depressurization and compromise of the capability of 
the windshield to withstand a bird strike.

DATES: This AD is effective July 21, 2015.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of July 21, 
2015.

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 [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. 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-2014-0249.

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-
0249; 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 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:

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 April 16, 
2014 (79 FR 21416). The NPRM was prompted by reports of non-conforming 
windshield supports (coupe rails). The NPRM proposed to require a 
general visual inspection to detect gouging and scratches and to 
determine if a radius has been removed; an ultrasound inspection to 
measure the dimensions of the lower coupe rails; an eddy current 
inspection to detect cracks of the lower coupe rails; replacement of 
the lower coupe rails if necessary; and revision of the maintenance or 
inspection program, as applicable. We are issuing this AD to detect and 
correct non-conforming windshield supports, which could result in 
uncontrolled cabin depressurization. Non-conforming windshield supports 
could also compromise the capability of the windshield to withstand a 
bird strike.

Explanation of Changes Made to Paragraph (h) of This AD

    We revised paragraph (h) of this AD to state that incorporation of 
certain tasks into the maintenance or inspection program, as 
applicable, must be done in accordance with a method approved by the 
Manager, Wichita Aircraft Certification Office (ACO), ACE-115W, FAA. 
For informational purposes, we have added new Notes 1 and 2 to 
paragraph (h) of this AD to refer to the latest maintenance manuals as 
guidance material for revising the maintenance or inspection program. 
(Earlier revisions were referenced previously in table 1 to paragraph 
(h) of the NPRM (79 FR 21416, April 16, 2014)). The change to this AD 
should allow operators to obtain appropriate versions of maintenance 
manuals in order to facilitate compliance.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the NPRM (79 
FR 21416, April 16, 2014), and the FAA's response to each comment.

Request for Credit for Previous Actions

    Learjet Inc. requested that we revise the NPRM (79 FR 21416, April 
16, 2014) to clarify whether actions accomplished using Bombardier 
Recommended Service Bulletin 40-56-03, dated April 30, 2012; or 
Bombardier Recommended Service Bulletin 45-56-3, dated April 30, 2012; 
is acceptable for compliance with the actions required by paragraph (g) 
of the NPRM. Learjet Inc. reasoned that many operators have already 
done those actions using this service information.
    We agree to clarify. Actions required by paragraph (g) of this AD, 
if performed before the effective date of this AD using Bombardier 
Recommended Service Bulletin 40-56-03, dated April 30, 2012; or 
Bombardier Recommended Service Bulletin 45-56-3, dated April 30, 2012; 
as applicable; are acceptable for compliance with the requirements of 
paragraph (g) of this AD. We have added a new paragraph (j) to this AD 
to provide credit for these actions. We have redesignated subsequent 
paragraphs accordingly.

Request To Incorporate Updated Inspection Reference Number (IRN)

    Learjet Inc. requested that we revise table 1 to paragraph (h) of 
the NPRM (79 FR 21416, April 16, 2014) to allow the incorporation of 
IRN V5323168, as specified in Bombardier Learjet 45 Maintenance Manual 
(MM) MM-104, Revision 62; and Bombardier Learjet 40 Maintenance Manual 
MM-105 Revision 30; both dated June 2, 2014. Learjet Inc. explained 
that IRN U5323168 was revised to V5323168 in Bombardier Learjet 45 
Maintenance Manual MM-104, Revision 62; and Bombardier Learjet 40 
Maintenance Manual MM-105, Revision 30; both dated June 2, 2014. 
Learjet Inc. stated that there were no actual changes to the content of 
the IRN in Chapter 4 of the MMs, but the ``U'' was revised to a ``V'' 
to coincide with changes to the verbiage in the same IRN in Chapter 5 
of those MMs.
    As discussed previously, we added new Notes 1 and 2 to paragraph 
(h) of this AD to refer to the latest revisions of the maintenance 
manuals, which include references to the appropriate IRNs referenced by 
the commenter. No additional change to this AD is necessary.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this AD with the changes described previously and minor editorial 
changes. We have determined that these minor changes:
     Are consistent with the intent that was proposed in the 
NPRM (79 FR 21416, April 16, 2014) for correcting the unsafe condition; 
and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM (79 FR 21416, April 16, 2014).
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this AD.

[[Page 34260]]

Related Service Information Under 1 CFR Part 51

    We reviewed Bombardier Recommended Service Bulletin 40-56-03, 
Revision 1, dated October 15, 2012; and Bombardier Recommended Service 
Bulletin 45-56-3, Revision 1, dated October 15, 2012. The service 
information describes procedures for a general visual inspection of the 
coupe rails to detect gouging and scratches, and to determine if a 
radius has been removed; an ultrasound inspection to measure the 
dimensions of the lower coupe rails; an eddy current inspection to 
detect cracks of the lower coupe rails; and replacement of the lower 
coupe rails if necessary. 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 of this AD.

Costs of Compliance

    We estimate that this AD affects 351 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
----------------------------------------------------------------------------------------------------------------
Inspection......................  40 work-hours x     $77...............  $3,477 per          $1,220,427 per
                                   $85 per hour =                          inspection cycle.   inspection cycle.
                                   $3,400 per
                                   inspection cycle.
Maintenance or inspection         1 work hour x $85   None..............  $85...............  $29,835.
 program revision.                 per hour = $85.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary replacement 
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
----------------------------------------------------------------------------------------------------------------
Replacement........................  500 work-hours (to replace   $15,000 (to replace     $57,500 (to replace
                                      both coupe rails) x $85      both coupe rails).      both coupe rails).
                                      per hour = $42,500.
----------------------------------------------------------------------------------------------------------------

    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):

2015-12-06 Learjet Inc.: Amendment 39-18180; Docket No. FAA-2014-
0249; Directorate Identifier 2012-NM-211-AD.

(a) Effective Date

    This AD is effective July 21, 2015.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Learjet Inc. Model 45 airplanes, certificated 
in any category, as identified in Bombardier Recommended Service 
Bulletin 40-56-03, Revision 1, dated October 15, 2012 (for airplanes 
having serial numbers (S/Ns) 45-2000 through 45-2120 inclusive, and 
S/Ns 45-2122 through 45-2130 inclusive); and Bombardier Recommended 
Service Bulletin 45-56-3, Revision 1, dated October 15, 2012 (for 
airplanes having S/Ns 45-005 through 45-427 inclusive).

(d) Subject

    Air Transport Association (ATA) of America Code 53, Fuselage.

[[Page 34261]]

(e) Unsafe Condition

    This AD was prompted by reports of non-conforming windshield 
supports (coupe rails). We are issuing this AD to detect and correct 
non-conforming windshield supports, which could result in 
uncontrolled cabin depressurization, and compromise of the 
capability of the windshield to withstand a bird strike.

(f) Compliance

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

(g) Inspections and Corrective Actions

    Within 600 flight hours or 36 months after the effective date of 
this AD, whichever occurs first: Do the inspections specified in 
paragraphs (g)(1) through (g)(3) of this AD. Do all inspections and 
corrective actions specified in paragraphs (g)(1) through (g)(3) of 
this AD, in accordance with the Accomplishment Instructions of 
Bombardier Recommended Service Bulletin 40-56-03, Revision 1, dated 
October 15, 2012 (for airplanes having S/Ns 45-2000 through 45-2120 
inclusive, and 45-2122 through 45-2130 inclusive); or Bombardier 
Recommended Service Bulletin 45-56-3, Revision 1, dated October 15, 
2012 (for airplanes having S/Ns 45-005 through 45-427 inclusive).
    (1) Do a general visual inspection of the coupe rails to detect 
gouging and scratches and to determine whether a radius has been 
removed or damaged.
    (i) If gouging or scratches are found, before further flight, 
burnish or blend the gouges and scratches.
    (ii) If the radius has been removed or damaged, before further 
flight, restore the radius.
    (2) Do an ultrasound inspection to measure the dimensions of the 
lower coupe rails.
    (i) If the coupe rail has an ``X'' dimension of 0.246 (6.248 
millimeters (mm)) or greater, and a ``Y'' dimension of 0.148 (3.759 
mm) or greater: Before further flight, identify the coupe rail, in 
accordance with table 1 of Bombardier Recommended Service Bulletin 
40-56-03, Revision 1, dated October 15, 2012 (for airplanes having 
S/Ns 45-2000 through 45-2120 inclusive, and S/Ns 45- 2122 through 
45-2130 inclusive); or Bombardier Recommended Service Bulletin 45-
56-3, Revision 1, dated October 15, 2012 (for airplanes having S/Ns 
45-005 through 45-427 inclusive).
    (ii) If the coupe rail has an ``X'' dimension between 0.246 
(6.248 mm) and 0.166 (4.216 mm) or a ``Y'' dimension between 0.148 
(3.759 mm) and 0.134 (3.403 mm): Before further flight, identify the 
coupe rail, in accordance with table 2 of Bombardier Recommended 
Service Bulletin 40-56-03, Revision 1, dated October 15, 2012 (for 
airplanes having S/Ns 45-2000 through 45-2120 inclusive, and S/Ns 
45- 2122 through 45-2130 inclusive); or Bombardier Recommended 
Service Bulletin 45-56-3, Revision 1, dated October 15, 2012 (for 
airplanes having S/Ns 45-005 through 45-427 inclusive).
    (iii) If any coupe rail ``X'' dimension is below 0.166 (4.216 
mm) or ``Y'' dimension is below 0.134 (3.403 mm): Before further 
flight, replace that coupe rail with a new coupe rail.
    (3) Do a flange and radius eddy current inspection for cracks of 
the left-hand and right-hand lower coupe rails.
    (i) If no crack is found, before further flight, mark the new 
data plate.
    (ii) If any crack is found, before further flight, replace the 
coupe rail with a new coupe rail.

(h) Maintenance/Inspection Program Revision

    Within 30 days after the effective date of this AD: Revise the 
maintenance or inspection program (as applicable) to incorporate 
tasks for inspections of the lower coupe rail radius/windscreen 
retainer attach and replacement of the coupe rails, in accordance 
with a method approved by the Manager, Wichita Aircraft 
Certification Office (ACO), ACE-115W, FAA.

    Note 1 to paragraph (h) of this AD: For Model 40 airplanes, the 
instructions provided in Bombardier Learjet 40 Maintenance Manual 
MM-105, Revision 30, dated June 2, 2014, provide guidance for 
revising the maintenance or inspection program to include 
replacements of the coupe rails and maintenance requirements/
structure checks of the lower coupe rail radius/windscreen retainer 
attach. This service information is not incorporated by reference in 
this AD.


    Note 2 to paragraph (h) of this AD: For Model 45 airplanes, the 
instructions provided in Bombardier Learjet 45 Maintenance Manual 
MM-104, Revision 62, dated June 2, 2014, provide guidance for 
revising the maintenance or inspection program to include 
replacements of the coupe rails and maintenance requirements/
structure checks of the lower coupe rail radius/windscreen retainer 
attach. This service information is not incorporated by reference in 
this AD.

(i) No Alternative Actions or Intervals

    After accomplishing the revision required by paragraph (h) of 
this AD, no alternative IRN task or interval may be used unless the 
IRN task or interval is approved as an alternative method of 
compliance (AMOC) in accordance with the procedures specified in 
paragraph (k) of this AD.

(j) Credit for Previous Actions

    This paragraph provides credit for actions required by paragraph 
(g) of this AD, if those actions were performed before the effective 
date of this AD using Bombardier Recommended Service Bulletin 40-56-
03, dated April 30, 2012 (for airplanes having S/Ns 45-2000 through 
45-2120 inclusive, and 45-2122 through 45-2130 inclusive); or 
Bombardier Recommended Service Bulletin 45-56-3, dated April 30, 
2012 (for airplanes having S/Ns 45-005 through 45-427 inclusive); 
which are not incorporated by reference in this AD.

(k) 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 
(l)(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.

(l) Related Information

    (1) For more information about this AD, contact Paul Chapman, 
Aerospace Engineer, Airframe Branch, ACE-118W, FAA, Wichita ACO, 
1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, KS 
67209; phone: 316-946-4152; fax: 316-946-4107; email: 
[email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (m)(3) and (m)(4) of this AD.

(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) Bombardier Recommended Service Bulletin 40-56-03, Revision 
1, dated October 15, 2012.
    (ii) Bombardier Recommended Service Bulletin 45-56-3, Revision 
1, dated October 15, 2012.
    (3) 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.
    (4) You may view this service information at 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.
    (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: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on June 3, 2015.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-14396 Filed 6-15-15; 8:45 am]
 BILLING CODE 4910-13-P