Airworthiness Directives; LET Aeronautical Works Model L-13 “Blanik” Sailplanes

[Federal Register Volume 65, Number 199 (Friday, October 13, 2000)]
[Rules and Regulations]
[Pages 60845-60846]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-25548]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-CE-91-AD; Amendment 39-11922; AD 2000-20-11]
RIN 2120-AA64


Airworthiness Directives; LET Aeronautical Works Model L-13 
``Blanik'' Sailplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to all LET Aeronautical Works (LET) Model L-13 ``Blanik'' 
sailplanes. This AD requires you to inspect the tail-fuselage hinge for 
strength requirements and damage, and also requires you to replace any 
hinge with damage or that does not meet strength requirements. This AD 
is the result of mandatory continuing airworthiness information (MCAI) 
issued by the airworthiness authority for the Czech Republic. The 
actions specified by this AD are intended to detect and correct any 
tail-fuselage hinge that is damaged or has inadequate material 
characteristics. Any tail-fuselage hinge with damage or inadequate 
material characteristics could fail and result in loss of controlled 
flight.

DATES: This AD becomes effective on November 27, 2000.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in the regulations as of 
November 27, 2000.

ADDRESSES: You may get the service information referenced in this AD 
from LET Aeronautical Works, Kunovice 686 04, Czech Republic; 
telephone: +420 632 55 44 96; facsimile: +420 632 56 41 13. You may 
examine this information at the Federal Aviation Administration (FAA), 
Central Region, Office of the Regional Counsel, Attention: Rules Docket 
No. 99-CE-91-AD, 901 Locust, Room 506, Kansas City, Missouri 64106; or 
at the Office of the Federal Register, 800 North Capitol Street, NW, 
suite 700, Washington, DC 20001.

FOR FURTHER INFORMATION CONTACT: Mike Kiesov, Aerospace Engineer, FAA, 
Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 
64106; telephone: (816) 329-4144; facsimile: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Discussion

    What events have caused this AD? The Civil Aviation Authority 
(CAA), which is the airworthiness authority for the Czech Republic, 
recently notified the FAA that an unsafe condition may exist on all LET 
Model L-13 ``Blanik'' sailplanes. The CAA reports an incident involving 
one of the affected sailplanes where the tail-fuselage attachment 
fitting was damaged. Further analysis reveals that the material 
characteristics of the tail-fuselage attachment fitting were 
inadequate.
    What are the consequences if the condition is not corrected? The 
tail-fuselage attachment fitting is a primary structural element within 
the empennage. Failure of this part, if not detected and corrected, 
could result in loss of controlled flight.
    Has FAA taken any action to this point? We issued a proposal to 
amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to 
include an AD that would apply to all LET Model L-13 ``Blanik'' 
sailplanes. This proposal was published in the Federal Register as a 
notice of proposed rulemaking (NPRM) on August 9, 2000 (65 FR 48648). 
The NPRM proposed to require you to inspect the tail-fuselage hinge for 
strength requirements and damage, and would require you to replace any 
hinge with damage or that does not meet strength requirements.
    Was the public invited to comment? Interested persons were afforded 
an opportunity to participate in the making of this amendment. No 
comments were received on the proposed rule or the FAA's determination 
of the cost to the public.

The FAA's Determination

    What is FAA's Final Determination on this Issue? After careful 
review of all available information related to the subject presented 
above, we have determined that air safety and the public interest 
require the adoption of the rule as proposed except for minor editorial 
corrections. We determined that these minor corrections:
    <bullet> Will not change the meaning of the AD; and
    <bullet> Will not add any additional burden upon the public than 
was already proposed.

Cost Impact

    How many sailplanes does this AD impact? We estimate that this AD 
affects 140 sailplanes in the U.S. registry.
    What is the cost impact of the inspection for the affected 
sailplanes on the U.S. Register? We estimate that it will take 
approximately 4 workhours per sailplane to accomplish the inspection, 
at an average labor rate of $60 an hour. Based on the cost factors 
presented above, we estimate the total cost impact of the inspection on 
U.S. operators to be $33,600, or $240 per sailplane.
    What is the cost impact of the replacement for the affected 
sailplanes on the U.S. Register? We estimate that it will take 
approximately 16 workhours per sailplane to accomplish the replacement 
(as necessary), at an average labor rate of $60 an hour. The 
manufacturer will provide the replacement attachment fittings at no 
cost. Based on the cost factors presented above, we estimate the total 
labor cost impact of the replacement on U.S. operators to be $960 per 
sailplane.

Regulatory Impact

    Does this AD impact various entities? The regulations adopted 
herein will not

[[Page 60846]]

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. 
Therefore, it is determined that this final rule does not have 
federalism implications under Executive Order 13132.
    Does this AD involve a significant rule or regulatory action? For 
the reasons discussed above, I certify that this action (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. A copy 
of the final evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

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 Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    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]

    2. FAA amends Section 39.13 by adding a new AD to read as follows:

2000-20-11  LET Aeronautical Works: Amendment 39-11922; Docket No. 
99-CE-91-AD.

    (a) What sailplanes are affected by this AD? This AD applies to 
Model L-13 ``Blanik'' sailplanes, all serial numbers, certificated 
in any category.
    (b) Who must comply with this AD? Anyone who wishes to operate 
any of the above sailplanes on the U.S. Register must comply with 
this AD.
    (c) What problem does this AD address? The actions specified by 
this AD are intended to prevent the tail-fuselage hinge failing and 
consequent loss of controlled flight.
    (d) What actions must I accomplish to address this problem? To 
address this problem, you must accomplish the following:

------------------------------------------------------------------------
           Actions              Compliance times         Procedures
------------------------------------------------------------------------
(1) Inspect the tail-         Within 60 days after  Follow the
 fuselage attachment           November 27, 2000     procedures in
 fitting, part number (P/N)    (the effective date   Mandatory Bulletin
 A 102 021N, for damage and    of this AD).          No. L13/085a, dated
 material hardness.                                  November 17, 1999.
(2) If the tail-fuselage      Before further        You must notify LET
 attachment fitting is         flight after the      Aeronautical Works
 damaged or the material       inspection.           and request they
 does not meet the hardness                          send the
 requirements specified in                           replacement part
 the service bulletin, you                           with installation
 must replace the tail-                              instructions.
 fuselage attachment fitting.
(3) Do not install, on any    As of November 27,    Inspect any
 sailplane, a P/N A 102 021N   2000 (the effective   attachment fitting
 attachment fitting that has   date of this AD).     in accordance with
 not passed the inspection                           the previously
 requirements specified in                           referenced service
 paragraph (d)(1) of this AD.                        bulletin.
------------------------------------------------------------------------

    (e) Can I comply with this AD in any other way? You may use an 
alternative method of compliance or adjust the compliance time if:
    (1) Your alternative method of compliance provides an equivalent 
level of safety; and
    (2) The Manager, Small Airplane Directorate, approves your 
alternative. Submit your request through an FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Small Airplane Directorate, 901 Locust, Room 301, Kansas 
City, Missouri 64106.


    Note 1: This AD applies to each sailplane identified in 
paragraph (a) of this AD, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For sailplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (e) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if you have not eliminated the unsafe 
condition, specific actions you propose to address it.

    (f) Where can I get information about any already-approved 
alternative methods of compliance? Contact Mike Kiesov, Aerospace 
Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, 
Kansas City, Missouri 64106; telephone: (816) 329-4144; facsimile: 
(816) 329-4090.
    (g) What if I need to fly the sailplane to another location to 
comply with this AD? The FAA can issue a special flight permit under 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate your sailplane to a location where 
you can accomplish the requirements of this AD.
    (h) Are any service bulletins incorporated into this AD by 
reference? Actions required by this AD must be done in accourdance 
with LET Mandatory Bulletin No. L13/085a, dated November 17, 1999. 
The Director of the Federal Register approved this incorporation by 
reference under 5 U.S.C. 552(a) and 1 CFR part 51. You can get 
copies from LET Aeronautical Works, Kunovice 686 04, Czech Republic; 
telephone: +420 632 55 44 96; facsimile: +420 632 611 26. You can 
look at copies at the FAA, Central Region, Office of the Regional 
Counsel, 901 Locust, Room 506, Kansas City, Missouri, or at the 
Office of the Federal Register, 800 North Capitol Street, NW, suite 
700, Washington, DC 20001.
    (i) When does this amendment become effective ? This amendment 
becomes effective on November 27, 2000.



    Note 2: The subject of this AD is addressed in Czech Republic AD 
Number CAA-AD-T-112/1999, dated November 18, 1999.


    Issued in Kansas City, Missouri, on September 28, 2000.
Michael Gallagher,
Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 00-25548 Filed 10-12-00; 8:45 am]
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