[Federal Register Volume 64, Number 113 (Monday, June 14, 1999)]
[Proposed Rules]
[Pages 31760-31762]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-14935]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-CE-16-AD]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to adopt a new airworthiness directive 
(AD) that would apply to all LET Aeronautical Works (LET) Model L-13 
``Blanik'' sailplanes. The proposed AD would require painting (using a 
contrasting color, i.e., red paint) the left hand elevator drive 
mechanism in order to not have the elevator drive bellcrank 
inadvertently installed backwards. The proposed AD is the result of 
mandatory continuing airworthiness information (MCAI) issued by the 
airworthiness authority for the Czech Republic. The actions specified 
by the proposed AD are intended to prevent the elevator drive bellcrank 
from being installed backwards, which could result in an incorrect 
rigging of the elevator flight control with potential reduced or loss 
of control of the sailplane.

DATES: Comments must be received on or before July 14, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 99-CE-16-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106. Comments may be inspected at this location 
between 8 a.m. and 4 p.m., Monday through Friday, holidays excepted.
    Service information that applies to the proposed AD may be obtained 
from LET Aeronautical Works, Kunovice 686 04, Czech Republic; 
telephone: +420 632 55 44 96; facsimile: +420 632 611 26. This 
information also may be examined at the Rules Docket at the address 
above.

FOR FURTHER INFORMATION CONTACT: Mike Kiesov, Aerospace Engineer, FAA, 
Small Airplane Directorate, 1201 Walnut, suite 900, Kansas City, 
Missouri 64106; telephone: (816) 426-6934; facsimile: (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications should identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report that summarizes each FAA-public contact concerned 
with the substance of this

[[Page 31761]]

proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket No. 99-CE-16-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Central Region, Office of the Regional Counsel, Attention: 
Rules Docket No. 99-CE-16-AD, Room 1558, 601 E. 12th Street, Kansas 
City, Missouri 64106.

Discussion

    The Civil Aviation Authority of the Czech Republic (CAA CZ), which 
is the airworthiness authority for the Czech Republic, notified the FAA 
that an unsafe condition may exist on certain LET Model L-13 ``Blanik'' 
sailplanes. The CAA CZ reports a recent accident of one of the affected 
sailplanes where the elevator drive bellcrank was incorrectly 
installed.
    Improper installation of the elevator drive bellcrank, if not 
corrected, could result in an incorrect rigging of the elevator flight 
control with potential reduced or loss of control of the sailplane.

Relevant Service Information

    LET has issued Mandatory Bulletin No. L13/082a, dated December 10, 
1998, which specifies procedures for painting (using red paint) the 
left hand elevator drive mechanism in order to not have the elevator 
drive bellcrank inadvertently installed backwards. This includes 
procedures for dismantling and reassembling the elevator drive 
bellcrank.
    The CAA CZ classified this service bulletin as mandatory and issued 
Czech Republic AD Number : CAA-AD-4-099/98, dated December 30, 1998, in 
order to assure the continued airworthiness of these sailplanes in the 
Czech Republic.

The FAA's Determination

    This sailplane model is manufactured in the Czech Republic and is 
type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) and the applicable bilateral airworthiness agreement. Pursuant 
to this bilateral airworthiness agreement, the CAA CZ has kept the FAA 
informed of the situation described above.
    The FAA has examined the findings of the CAA CZ; reviewed all 
available information, including the service information referenced 
above; and determined that AD action is necessary for products of this 
type design that are certificated for operation in the United States.

Explanation of the Provisions of the Proposed AD

    Since an unsafe condition has been identified that is likely to 
exist or develop in other LET Model L-13 ``Blanik'' sailplanes of the 
same type design registered in the United States, the FAA is proposing 
AD action. The proposed AD would require painting (using a contrasting 
color, i.e., red paint) the left hand elevator drive mechanism in order 
to not have the elevator drive bellcrank inadvertently installed 
backwards. Accomplishment of the proposed action would be in accordance 
with LET Mandatory Bulletin No. L13/082a, dated December 10, 1998.

Compliance Time of the Proposed AD

    Although flight control problems caused by improper installation of 
the elevator drive bellcrank are only unsafe while the affected 
sailplanes are in flight, the condition could occur after any time the 
elevator drive bellcrank is reinstalled on the sailplane. The chance of 
this situation occurring is the same for a sailplane with 10 hours 
time-in-service (TIS) as it is for a sailplane with 500 hours TIS. For 
this reason, the FAA is utilizing a compliance based on calendar time 
instead of hours TIS in the proposed AD in order to assure that the 
unsafe condition is addressed on all sailplanes in a reasonable time 
period.

Cost Impact

    The FAA estimates that 140 sailplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 1 
workhour per sailplane to accomplish the proposed action, and that the 
average labor rate is approximately $60 an hour. Parts cost 
approximately $5 per sailplane. Based on these figures, the total cost 
impact of the proposed AD on U.S. operators is estimated to be $9,100, 
or $65 per sailplane.

Regulatory Impact

    The regulations proposed herein would not have substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    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) if promulgated, 
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 draft regulatory evaluation 
prepared for this action has been placed 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, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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. Section 39.13 is amended by adding a new airworthiness directive 
(AD) to read as follows:

LET Aeronautical Works: Docket No. 99-CE-16-AD.
    Applicability: Model L-13 ``Blanik'' sailplanes, all serial 
numbers, certificated in any category.

    Note 1: This AD applies to each sailplane identified in the 
preceding applicability provision, 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 (d) 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 the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.


[[Page 31762]]


    Compliance: Required as indicated in the body of this AD, unless 
already accomplished.
    To prevent the elevator drive bellcrank from being installed 
backwards, which could result in an incorrect rigging of the 
elevator flight control with potential reduced or loss of control of 
the sailplane, accomplish the following:
    (a) Within the next 3 calendar months after the effective date 
of this AD, paint (using a contrasting color, i.e., red paint) the 
elevator drive mechanism to prevent the elevator drive bellcrank 
from being inadvertently installed backwards. Accomplish this action 
in accordance with the Work Procedure section, including Figure 1, 
of LET Mandatory Bulletin No. L13.082a, dated December 10, 1998.
    (b) As of the effective date of this AD, no person may install, 
on any affected sailplane, an elevator drive bellcrank where the 
following has not been accomplished:
    (1) The elevator bellcrank inspected to assure that it is not 
installed backwards; and
    (2) The elevator drive bellcrank painted as required by 
paragraph (a) of this AD.
    (c) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the sailplane to a location where 
the requirements of this AD can be accomplished.
    (d) An alternative method of compliance or adjustment of the 
compliance times that provides an equivalent level of safety may be 
approved by the Manager, Small Airplane Directorate, FAA, 1201 
Walnut, suite 900, Kansas City, Missouri 64106. The request shall be 
forwarded through an appropriate FAA Maintenance Inspector, who may 
add comments and then send it to the Manager, Small Airplane 
Directorate.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Small Airplane Directorate.

    (e) Questions or technical information related to LET Mandatory 
Bulletin No. L13/082a, dated December 10, 1998, should be directed 
to LET Aeronautical Works, Kunovice 686 04, Czech Republic; 
telephone: +420 632 55 44 96; facsimile: +420 632 611 26. This 
service information may be examined at the FAA, Central Region, 
Office of the Regional Counsel, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

    Note 3: The subject of this AD is addressed in Czec Republic AD 
Number: CAA-AD-4-099/98, dated December 30, 1998.

    Issued in Kansas City, Missouri, on June 4, 1999.
Marvin R. Nuss,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-14935 Filed 6-11-99; 8:45 am]
BILLING CODE 4910-13-P