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[Federal Register Volume 82, Number 1 (Tuesday, January 3, 2017)]
[Rules and Regulations]
[Pages 7-10]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-30412]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-0457; Directorate Identifier 2015-NM-084-AD; 
Amendment 39-18751; AD 2016-25-25]
RIN 2120-AA64

Airworthiness Directives; BAE Systems (Operations) Limited 
Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: We are superseding Airworthiness Directive (AD) 2012-11-15 for 
all BAE Systems (Operations) Limited Model 4101 airplanes. AD 2012-11-
15 required a one-time detailed inspection for cracks, corrosion, and 
other defects of the rear face of the wing rear spar, and repair if 
necessary. This new AD requires repetitive detailed inspections, and 
repair if necessary. This AD was prompted by new reports of cracking 
found in the wing rear spar and technical analysis results, which 
confirmed that the crack initiation and propagation are due to fatigue, 
with no indication of any other crack initiation mechanism (e.g., 
stress corrosion). We are issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective February 7, 2017.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of February 7, 
2017.

ADDRESSES: For service information identified in this final rule, 
contact BAE Systems (Operations) Limited, Customer Information 
Department, Prestwick International Airport, Ayrshire, KA9 2RW, 
Scotland, United Kingdom; telephone +44 1292 675207; fax +44 1292 
675704; email RApublications@baesystems.com; Internet http://www.baesystems.com/Businesses/RegionalAircraft/index.htm. 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-2016-0457.

[[Page 8]]

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-
0457; 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 (telephone 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: Todd Thompson, Aerospace Engineer, 
International Branch, ANM-116, Transport Airplane Directorate, FAA, 
1601 Lind Avenue SW., Renton, WA 98057-3356; telephone 425-227-1175; 
fax 425-227-1149.

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to supersede AD 2012-11-15, Amendment 39-17079 (77 FR 36127, 
June 18, 2012) (``AD 2012-11-15''). AD 2012-11-15 applied to all BAE 
Systems (Operations) Limited Model 4101 airplanes. The NPRM published 
in the Federal Register on January 21, 2016 (81 FR 3350) (``the 
NPRM''). The NPRM was prompted by new reports of cracking found in the 
wing rear spar and technical analysis results, which confirmed that the 
crack initiation and propagation are due to fatigue, with no indication 
of any other crack initiation mechanism (e.g., stress corrosion). The 
NPRM proposed to require a one-time detailed inspection for cracks, 
corrosion, and other defects of the rear face of the wing rear spar, 
and repair if necessary. The NPRM also proposed to require repetitive 
detailed inspections, and repair if necessary. We are issuing this AD 
to detect and correct cracking in the wing rear spar, which could 
propagate to a critical length, possibly affecting the structural 
integrity of the area and resulting in a fuel tank rupture, with 
consequent damage to the airplane and possible injury to its occupants.
    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Union, has issued EASA 
Airworthiness Directive 2015-0100, dated June 3, 2015 (referred to 
after this as the Mandatory Continuing Airworthiness Information, or 
``the MCAI''), to correct an unsafe condition for all BAE Systems 
(Operations) Limited Model 4101 airplanes. The MCAI states:

    During an investigation of a fuel leak on the rear spar of a 
Jetstream 4100 aeroplane, 4 cracks were found between Ribs 6 and 7 
(immediately inboard of the inboard engine rib). The cracks 
initiated at adjacent fastener bores in the rear spar upper boom, 
and progressed downwards, diagonally, into the rear spar web.
    These cracks, if not detected and corrected, could propagate to 
a critical length, affecting the structural integrity of the area, 
possibly resulting in a fuel tank rupture with consequent damage to 
the aeroplane and injury to occupants.
    Prompted by these findings, EASA issued AD 2011-0096 [which 
corresponds to FAA AD 2012-11-15, Amendment 39-17079 (77 FR 36127, 
June 18, 2012)] to require a one-time [detailed] inspection [for 
cracks, corrosion, and other defects] of the rear face of the wing 
rear spar and the accomplishment of applicable corrective actions 
[i.e., repair], depending on findings. Initial analysis of the event 
did not lead to the conclusion that the cracking was fatigue 
related, therefore [EASA] AD 2011-0096 did not require repetitive 
inspections.
    Since that [EASA] AD [2011-0096] was issued, the results of the 
technical analysis confirmed that the cracks were due to fatigue, 
with no indication of any other crack initiation mechanism (e.g. 
stress corrosion). In addition, further similar in-service events 
have been reported. During investigation of those events, further 
metallurgical analysis indicated that the crack initiation and 
propagation are indeed fatigue driven and occur at the same 
location.
    To address this unsafe condition, a review of the inspection 
interval was undertaken based on the cracks from both aeroplanes and 
BAE Systems (Operations) Ltd issued Service Bulletin (SB) J41-A57-
029 Revision 3 in order to reduce the inspection interval of the 
wing rear spar from 2 000 flight cycles (FC) to 1 600 FC.
    For the reasons described above, this [EASA] AD supersedes 
[EASA] AD 2011-0096, without retaining its requirements, introduces 
repetitive inspections and, depending on findings, requires the 
accomplishments of applicable corrective action(s) [i.e., repair].

    You may examine the MCAI in the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2016-
0457.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We received no comments on the NPRM or on the determination of 
the cost to the public.

Explanation of Change in This AD

    The NPRM incorrectly referred to Subject 57-00-00, Wings General, 
of Chapter 57, Wings, of the BAE Systems (Operations) Limited Jetstream 
Series 4100 Structural Repair Manual (SRM), Volume 1, Revision 32, 
dated October 15, 2014, for damage criteria and repair instructions. We 
have revised this final rule to refer to Chapter 57 of the SRM instead 
of Subject 57-00-00.

Conclusion

    We reviewed the available data 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:
     Are consistent with the intent that was proposed in the 
NPRM for correcting the unsafe condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

    BAE Systems (Operations) Limited has issued Alert Service Bulletin 
J41-A57-029, Revision 3, dated April 8, 2014. The service information 
describes detailed inspections for cracks, corrosion, and other defects 
of the rear face of the wing rear spars.
    BAE Systems (Operations) Limited also has issued Chapter 57, Wings, 
of the Jetstream Series 4100 SRM, Volume 1, Publication Ref. No. 
(Transmittal No.) SA 4-4100/SRM/400, Revision 32, dated October 15, 
2014. Among other actions, Chapter 57 describes damage criteria and 
procedures for repairing the wing structure.
    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.

Costs of Compliance

    We estimate that this AD affects 15 airplanes of U.S. registry.
    We also estimate that it takes up to 25 work-hours per product to 
comply with the basic requirements of this AD. The average labor rate 
is $85 per work-hour. Based on these figures, we estimate the cost of 
this AD on U.S. operators to be up to $31,875, or up to $2,125 per 
product.
    We have received no definitive data that enables us to provide a 
cost estimate for the on-condition actions (repairing cracks, 
corrosion, and defects) specified in this AD.

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:

[[Page 9]]

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 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 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.

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 removing Airworthiness Directive (AD) 
2012-11-15, Amendment 39-17079 (77 FR 36127, June 18, 2012), and adding 
the following new AD:

2016-25-25 Bombardier: Amendment 39-18751; Docket No. FAA-2016-0457; 
Directorate Identifier 2015-NM-084-AD.

(a) Effective Date

    This AD is effective February 7, 2017.

(b) Affected ADs

    This AD replaces AD 2012-11-15, Amendment 39-17079 (77 FR 36127, 
June 18, 2012) (``AD 2012-11-15'').

(c) Applicability

    This AD applies to BAE (Operations) Limited Model 4101 
airplanes, certificated in any category, all models and all serial 
numbers.

(d) Subject

    Air Transport Association (ATA) of America Code 57, Wings.

(e) Reason

    This AD was prompted by new reports of cracking found in the 
wing rear spar and technical analysis results, which confirmed that 
the crack initiation and propagation are due to fatigue, with no 
indication of any other crack initiation mechanism (e.g., stress 
corrosion). We are issuing this AD to detect and correct cracking in 
the wing rear spar, which could propagate to a critical length, 
possibly affecting the structural integrity of the area and 
resulting in a fuel tank rupture, with consequent damage to the 
airplane and possible injury to its occupants.

(f) Compliance

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

(g) Repetitive Inspections and Repair

    Within 30 days after the effective date of this AD, or within 
1,600 flight cycles since the most recent detailed inspection was 
done as specified in BAE Systems Alert Service Bulletin J41-A57-029, 
whichever occurs later: Do a detailed inspection for cracks, 
corrosion, and other defects (defects include scratches, dents, 
holes, damage to fastener holes, or damage to surface protection and 
finish) of the rear face of the wing rear spars, in accordance with 
the Accomplishment Instructions of BAE Systems Alert Service 
Bulletin J41-A57-029, Revision 3, dated April 8, 2014. Repeat the 
inspection thereafter at intervals not to exceed 1,600 flight 
cycles.
    (1) If any cracking, corrosion, or other defect is found within 
the criteria defined in Chapter 57, Wings, of the Jetstream Series 
4100 Structural Repair Manual (SRM), Volume 1, Publication Ref. No. 
(Transmittal No.) SA 4-4100/SRM/400, Revision 32, dated October 15, 
2014 (``Chapter 57 of the SRM''): Before further flight, repair the 
affected area, in accordance with the repair instructions of Chapter 
57 of the SRM.
    (2) If any cracking, corrosion, or other defect is found 
exceeding the criteria defined in Chapter 57 of the SRM: Before 
further flight, repair using a method approved by the Manager, 
International Branch, ANM-116, Transport Airplane Directorate, FAA; 
or the European Aviation Safety Agency (EASA); or BAE Systems 
(Operations) Limited's EASA Design Organization Approval (DOA).

(h) Repair Does Not Constitute Terminating Action Except for Certain 
Repairs

    Accomplishment of a repair as required by paragraphs (g)(1) and 
(g)(2) of this AD, does not constitute terminating action for the 
repetitive inspections required by paragraph (g) of this AD, unless 
the approved repair required by paragraph (g)(2) of this AD states 
otherwise (e.g., the approved repair states the repair terminates 
the inspections for the repaired area only).

(i) Other FAA AD Provisions

    The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
International Branch, ANM-116, Transport Airplane Directorate, 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 International Branch, send it to ATTN: Todd 
Thompson, Aerospace Engineer, International Branch, ANM-116, 
Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, 
WA 98057-3356; telephone 425-227-1175; fax 425-227-1149. Information 
may be emailed to: 9-ANM-116-AMOC-REQUESTS@faa.gov. 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. The 
AMOC approval letter must specifically reference this AD.
    (2) Contacting the Manufacturer: As of the effective date of 
this AD, for any requirement in this AD to obtain corrective actions 
from a manufacturer, the action must be accomplished using a method 
approved by the Manager, International Branch, ANM-116, Transport 
Airplane Directorate, FAA; or the EASA; or BAE Systems (Operations) 
Limited's EASA DOA. If approved by the DOA, the approval must 
include the DOA-authorized signature.

(j) Related Information

    Refer to Mandatory Continuing Airworthiness Information (MCAI) 
EASA Airworthiness Directive 2015-0100, dated June 3, 2015, for 
related information. This MCAI may be found in the AD docket on the 
Internet at http://www.regulations.gov by searching for and locating 
Docket No. FAA-2016-0457.

(k) 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 this AD specifies otherwise.
    (i) BAE Systems Alert Service Bulletin J41-A57-029, Revision 3, 
dated April 8, 2014.
    (ii) Chapter 57, Wings, of the BAE Systems (Operations) Limited 
Jetstream Series 4100 Structural Repair Manual, Volume 1, 
Publication Ref. No. (Transmittal No.) SA 4-

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4100/SRM/400, Revision 32, dated October 15, 2014.
    (3) For service information identified in this AD, contact BAE 
Systems (Operations) Limited, Customer Information Department, 
Prestwick International Airport, Ayrshire, KA9 2RW, Scotland, United 
Kingdom; telephone +44 1292 675207; fax +44 1292 675704; email 
RApublications@baesystems.com; Internet http://www.baesystems.com/Businesses/RegionalAircraft/index.htm.
    (4) You may view this 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.
    (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 December 6, 2016.
Dionne Palermo,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-30412 Filed 12-30-16; 8:45 am]
BILLING CODE 4910-13-P
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