Document ID: FAA-2010-0839-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Aircraft Industries a.s. (Type Certificate G24EU Previously Held by LETECKE ZAVODY a.s. and LET Aeronautical Works) Model L-13 Blanik Gliders
Posted Date: 2010-08-25T04:00Z

[Federal Register: August 25, 2010 (Volume 75, Number 164)]
[Rules and Regulations]               
[Page 52250-52253]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr25au10-9]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0839; Directorate Identifier 2010-CE-042-AD; 
Amendment 39-16418; AD 2010-18-05]
RIN 2120-AA64

 
Airworthiness Directives; Aircraft Industries a.s. (Type 
Certificate G24EU Previously Held by LETECK[Eacute] Z[Aacute]VODY a.s. 
and LET Aeronautical Works) Model L-13 Blanik Gliders

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: We are adopting a new airworthiness directive (AD) for the 
products listed above that will supersede an existing AD. This AD 
results from mandatory continuing airworthiness information (MCAI) 
issued by the aviation authority of another country to identify and 
correct an unsafe condition on an aviation product. The MCAI describes 
the unsafe condition as:

    A fatal accident occurred to a L-13 BLAN[Iacute]K sailplane, in 
which the main spar of the right wing failed near the root due to 
positive load. The right wing detached from the aircraft and the 
pilots lost control of the sailplane.
    The preliminary investigation has revealed that the fracture may 
have been due to fatigue.
    The AD 2010-0119-E required immediate inspection of the main 
spar at the root of the wing to detect fatigue cracking and the 
accomplishment of the relevant corrective actions as necessary. In 
addition, the AD 2010-0119-E imposed operational limitations. AD 
2010-0122-E retained the requirements of AD 2010-0119-E, which is 
superseded, and extended the applicability to L-13 A BLAN[Iacute]K 
sailplanes.

This AD requires actions that are intended to address the unsafe 
condition described in the MCAI.

DATES: This AD becomes effective August 30, 2010.
    We must receive comments on this AD by October 12, 2010.

ADDRESSES: You may send comments 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: 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.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Management Facility 
between 9

[[Page 52251]]

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 (telephone (800) 647-5527) is in the ADDRESSES section. Comments 
will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Greg Davison, Aerospace Engineer, 
Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 
64106, telephone: (816) 329-4130, fax: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Discussion

    On June 28, 2010, we issued AD 2010-14-15, Amendment 39-16360 (75 
FR 39795), dated July 13, 2010. That AD required actions intended to 
address an unsafe condition on the products listed above.
    Since we issued AD 2010-14-15, we have received preliminary 
information from the European Aviation Safety Agency (EASA), which is 
the Technical Agent for the Member States of the European Community, 
that identified fatigue as the failure mode in the fatal accident. The 
examination of the fractures in the wing flange straps found eight 
areas of fatigue cracking that originated from the surface of the bores 
used to rivet the flange straps to the hinge. The fatigue cracks had 
propagated to the surface of the flange straps and were not visible for 
inspection.
    In addition, we received several public comments indicating that 
the use of a 10X magnifier is not appropriate to assess the specified 
inspection areas and portions of the operational data requested by the 
current AD are not required for U.S. operators.
    EASA has issued Emergency AD No. 2010-0160-E, dated July 30, 2010 
(referred to after this as ``the MCAI''), to correct an unsafe 
condition for the specified products. The MCAI states:

    A fatal accident occurred to a L-13 BLAN[Iacute]K sailplane, in 
which the main spar of the right wing failed near the root due to 
positive load. The right wing detached from the aircraft and the 
pilots lost control of the sailplane.
    The preliminary investigation has revealed that the fracture may 
have been due to fatigue.
    The AD 2010-0119-E required immediate inspection of the main 
spar at the root of the wing to detect fatigue cracking and the 
accomplishment of the relevant corrective actions as necessary. In 
addition, the AD 2010-0119-E imposed operational limitations. AD 
2010-0122-E retained the requirements of AD 2010-0119-E, which is 
superseded, and extended the applicability to L-13 A BLAN[Iacute]K 
sailplanes.
    The requirements of AD 2010-0122-E were considered as interim 
action to immediately address the unsafe condition. Since issuance 
of AD 2010-0122-E, based on further information provided by the 
Austrian Accident Investigation Board, EASA has re-assessed the 
inspection method as described in Aircraft Industries a.s. Mandatory 
Bulletin No. L13/109a. EASA now concludes that the inspection method 
might not be sufficient for detecting the crack which means that the 
unsafe condition might still be present even if the sailplane has 
passed the inspection required by AD 2010-0122-E. Furthermore, the 
Type Certificate Holder indicates that it is extremely important to 
remain within the flight limitations specified in the Aircraft 
Industries a.s. Mandatory Bulletin No. L13/109a. For this reason, 
this AD further requires a record checking for determining if the 
sailplane has been operated within the flight limitations.
    For all the reasons stated above, as a precautionary measure, 
this AD is prohibiting operations when a sailplane does not pass the 
requirements of this AD. For those sailplanes, EASA is currently 
working with the Type Certificate Holder. When, as a result of the 
on-going investigation, a solution is later identified, further 
mandatory action is likely to follow.

You may obtain further information by examining the MCAI in the AD 
docket.

FAA's Determination and Requirements of the AD

    This product has been approved by the aviation authority of another 
country, and is approved for operation in the United States. Pursuant 
to our bilateral agreement with this State of Design Authority, they 
have notified us of the unsafe condition described in the MCAI and 
service information referenced above. We are issuing this AD because we 
evaluated all information provided by the State of Design Authority and 
determined the unsafe condition exists and is likely to exist or 
develop on other products of the same type design.

Differences Between This AD and the MCAI or Service Information

    We have reviewed the MCAI and related service information and, in 
general, agree with their substance. But we might have found it 
necessary to use different words from those in the MCAI to ensure the 
AD is clear for U.S. operators and is enforceable. In making these 
changes, we do not intend to differ substantively from the information 
provided in the MCAI and related service information.
    We might have also required different actions in this AD from those 
in the MCAI in order to follow FAA policies. Any such differences are 
described in a separate paragraph of the AD. These requirements take 
precedence over those copied from the MCAI.

FAA's 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 a 
fatal accident occurred in an L-13 Blanik glider. The main spar of the 
right wing of the accident glider failed near the root due to positive 
load. The right wing detached from the aircraft and the pilots lost 
control. The preliminary investigation has revealed that the fracture 
may have been due to fatigue. Therefore, we determined that notice and 
opportunity for public comment before issuing this AD are impracticable 
and that good cause exists for making this amendment effective in fewer 
than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety, and we did not precede it by notice and opportunity for public 
comment. We invite you to send any written relevant data, views, or 
arguments about this AD. Send your comments to an address listed under 
the ADDRESSES section. Include ``Docket No. FAA-2010-0839; Directorate 
Identifier 2010-CE-042-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 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 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: 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

[[Page 52252]]

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 DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and
    (3) 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

0
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 Amendment 39-16360 (75 FR 
39795), dated July 13, 2010, and adding the following new AD:

2010-18-05 Aircraft Industries a.s. (Type Certificate G24EU 
Previously Held by Leteck[eacute] Z[aacute]vody a.s. and LET 
Aeronautical Works): Amendment 39-16418; Docket No. FAA-2010-0839; 
Directorate Identifier 2010-CE-042-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective August 
30, 2010.

Affected ADs

    (b) This AD supersedes AD 2010-14-15; Amendment 39-16360.

Applicability

    (c) This AD applies to Aircraft Industries a.s. L-13 Blanik 
gliders, all serial numbers, certificated in any category.

Subject

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

Reason

    (e) The mandatory continuing airworthiness information (MCAI) 
states:

    A fatal accident occurred to a L-13 BLAN[Iacute]K sailplane, in 
which the main spar of the right wing failed near the root due to 
positive load. The right wing detached from the aircraft and the 
pilots lost control of the sailplane.
    The preliminary investigation has revealed that the fracture may 
have been due to fatigue.
    The AD 2010-0119-E required immediate inspection of the main 
spar at the root of the wing to detect fatigue cracking and the 
accomplishment of the relevant corrective actions as necessary. In 
addition, the AD 2010-0119-E imposed operational limitations. AD 
2010-0122-E retained the requirements of AD 2010-0119-E, which is 
superseded, and extended the applicability to L-13 A BLAN[Iacute]K 
sailplanes.
    The requirements of AD 2010-0122-E were considered as interim 
action to immediately address the unsafe condition. Since issuance 
of AD 2010-0122-E, based on further information provided by the 
Austrian Accident Investigation Board, EASA has re-assessed the 
inspection method as described in Aircraft Industries a.s. Mandatory 
Bulletin No. L13/109a. EASA now concludes that the inspection method 
might not be sufficient for detecting the crack which means that the 
unsafe condition might still be present even if the sailplane has 
passed the inspection required by AD 2010-0122-E. Furthermore, the 
Type Certificate Holder indicates that it is extremely important to 
remain within the flight limitations specified in the Aircraft 
Industries a.s. Mandatory Bulletin No. L13/109a. For this reason, 
this AD further requires a record checking for determining if the 
sailplane has been operated within the flight limitations.
    For all the reasons stated above, as a precautionary measure, 
this AD is prohibiting operations when a sailplane does not pass the 
requirements of this AD. For those sailplanes, EASA is currently 
working with the Type Certificate Holder. When, as a result of the 
on-going investigation, a solution is later identified, further 
mandatory action is likely to follow.

Actions and Compliance

    (f) To address this problem, before further flight after August 
30, 2010 (the effective date of this AD), incorporate an FAA-
approved inspection and/or modification program developed 
specifically for this AD. Corrective action is considered FAA-
approved if it is approved by the State of Design Authority (or 
their delegated agent). You are required to assure the product is 
airworthy before it is returned to service.

FAA AD Differences

    Note: This AD differs from the MCAI and/or service information 
as follows: The MCAI requires the owner/operator to submit data 
regarding certain operations including aerobatic operations, to the 
European Aviation Safety Agency (EASA) and Aircraft Industries, a.s. 
so they can determine whether further flight is permitted. The FAA 
does not require such data to be collected for operations in the 
United States. The FAA is relying on an inspection and/or 
modification program approved specifically for this AD to detect and 
correct cracks before further flight. Until such a program is 
approved, owners/operators may apply for an alternative method of 
compliance (AMOC) following 14 CFR 39.19 described in paragraph 
(f)(1) of this AD. The FAA will work with EASA and Aircraft 
Industries a.s. to determine if an acceptable level of safety is 
achieved with the AMOC proposal.

Other FAA AD Provisions

    (f) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
Standards Office, FAA, has the authority to approve AMOCs for this 
AD, if requested using the procedures found in 14 CFR 39.19. Send 
information to Attn: Greg Davison, Aerospace Engineer, FAA, Small 
Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 
64106; telephone: (816) 329-4130; fax: (816) 329-4090. Before using 
any approved AMOC on any airplane to which the AMOC applies, notify 
your appropriate principal inspector (PI) in the FAA Flight 
Standards District Office (FSDO), or lacking a PI, your local FSDO.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer or other source, use these 
actions if they are FAA-approved. Corrective actions are considered 
FAA-approved if they are approved by the State of Design Authority 
(or their delegated agent). You are required to assure the product 
is airworthy before it is returned to service.
    (3) Reporting Requirements: For any reporting requirement in 
this AD, under the provisions of the Paperwork Reduction Act (44 
U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has 
approved the information collection requirements and has assigned 
OMB Control Number 2120-0056.

Special Flight Permit

    (g) Under 14 CFR part 39.23, we are limiting the special flight 
permits for this AD by prohibiting aerobatic maneuvers.

Related Information

    (h) Refer to MCAI EASA Emergency AD No. 2010-0160-E, dated July 
30, 2010, for related information. For future service information 
that may be developed to address the unsafe condition specified in 
this AD, contact Aircraft Industries, a.s., Na Z[aacute]honech 1177, 
686 04 Kunovice, Czech Republic; telephone: +420 572 817 660; fax: 
+420 572 816 112; Internet: http://www.let.cz/; e-mail: ots@let.cz.

[[Page 52253]]

    Issued in Kansas City, Missouri, on August 17, 2010.
John Colomy,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-20877 Filed 8-24-10; 8:45 am]
BILLING CODE 4910-13-P