AD Amdt-39-11149

final rule

Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK 21 Gliders

AD Number
Amdt-39-11149
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 91-CE-25-AD
FR Citation
64 FR 20142
Technical illustration of an aircraft flight control surface and actuator
Problem area Flight controls

Unsafe Condition

Parallel rocker breaking at the elevator connection, potentially leading to loss of elevator control.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Replace the parallel rocker with a part of improved design. Revise the flight manual.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Not specified in the provided text.

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Affected Aircraft

Alexander Schleicher Segelflugzeugbau Model ASK 21 gliders equipped with the automatic elevator connection.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment revises Airworthiness Directive (AD) 95-11-15, which currently requires replacing the parallel rocker with a part of improved design and incorporating flight manual revisions on all Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK 21 gliders. AD 95-11-15 was the result of two incidents of the parallel rocker breaking at the elevator connection on the affected gliders. Since that time, the FAA has determined that the AD should only affect those Model ASK 21 gliders equipped with the automatic elevator connection. This AD retains the actions of AD 95-11-15, but only for those gliders with the automatic elevator connection incorporated. The actions specified in this AD are intended to continue to prevent possible loss of elevator control that could result from a broken parallel rocker.

Document Text

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[Federal Register Volume 64, Number 79 (Monday, April 26, 1999)]
[Rules and Regulations]
[Pages 20142-20144]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 99-10313]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 91-CE-25-AD; Amendment 39-11149; AD 95-11-15 R1]
RIN 2120-AA64


Airworthiness Directives; Alexander Schleicher Segelflugzeugbau 
Model ASK 21 Gliders

AGENCY: Federal Aviation Administration, DOT.

ACTION: Direct final rule; request for comments.

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SUMMARY: This amendment revises Airworthiness Directive (AD) 95-11-15, 
which currently requires replacing the parallel rocker with a part of 
improved design and incorporating flight manual revisions on all 
Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK 
21 gliders. AD 95-11-15 was the result of two incidents of the parallel 
rocker breaking at the elevator connection on the affected gliders. 
Since that time, the FAA has determined that the AD should only affect 
those Model ASK 21 gliders equipped with the automatic elevator 
connection. This AD retains the actions of AD 95-11-15, but only for 
those gliders with the automatic elevator connection incorporated. The 
actions specified in this AD are intended to continue to prevent 
possible loss of elevator control that could result from a broken 
parallel rocker.

DATES: Effective July 25, 1999.
    The incorporation by reference of certain publications as listed in 
the regulations was previously approved by the Director of the Federal 
Register as of July 14, 1995 (60 FR 29978, June 7, 1995).
    Comments for inclusion in the Rules Docket must be received on or 
before May 28, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 91-CE-25-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.
    Service information that applies to this AD may be obtained from 
Alexander Schleicher GmbH & Co., Segelflugzeugbau, Postfach 60, 36163 
Poppenhausen, Germany; telephone: ++49 (0) 6658-890; facsimile: ++49 
(0) 6658-8923. This information may also be examined at the Federal 
Aviation Administration (FAA), Central Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 91-CE-25-AD, Room 1558, 601 E. 
12th Street, Kansas City, Missouri 64106; or at the Office of the 
Federal Register, 800 North Capitol Street, NW, suite 700, Washington, 
DC.

FOR FURTHER INFORMATION CONTACT: Mr. Mike Kiesov, Aerospace Engineer, 
FAA, Small Airplane Directorate, 1201 Walnut, suite 900, Kansas City, 
Missouri 64106; telephone: (816) 426-6932; facsimile: (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Discussion

    AD 95-11-15, Amendment 39-9248 (60 FR 29978, June 7, 1995), 
currently requires the following on all Alexander Schleicher 
Segelflugzeugbau (Alexander Schleicher) Model ASK 21 gliders:


[[Page 20143]]


--Replacing the parallel rocker with a part of improved design; and
--Incorporating flight manual revisions.

    Accomplishment of these actions is required in accordance with 
Alexander Schleicher ASK 21 Technical Note No. 22, dated November 26, 
1990.
    AD 95-11-15 was the result of two incidents of the parallel rocker 
breaking at the elevator connection on the affected gliders.
    The actions specified in AD 95-11-15 are intended to prevent 
possible loss of elevator control that could result from a broken 
parallel rocker.

Actions Since Issuance of Previous Rule

    Since AD 95-11-15 became effective, the FAA has determined that the 
AD should only affect those Model ASK 21 gliders equipped with the 
automatic elevator connection. Model ASK 21 gliders incorporating 
serial numbers 21206 through 21473 were equipped with the automatic 
elevator connection at manufacture, and any earlier serial numbers 
could be modified to incorporate an automatic elevator connection. 
Alexander Schleicher Technical Note No. 11 includes the procedures 
necessary to accomplish this modification.

The FAA's Determination

    After examining the circumstances and reviewing all available 
information related to the incidents described above, the FAA has 
determined that:

--The applicability of AD 95-11-15 should be limited to only those 
Model ASK 21 gliders equipped with the automatic elevator connection; 
and
--AD action should be taken to continue to prevent possible loss of 
elevator control that could result from a broken parallel rocker.

Explanation of the Provisions of This AD

    Since an unsafe condition has been identified that is likely to 
exist or develop in other Alexander Schleicher Model ASK 21 gliders of 
the same type design registered in the United States, the FAA is 
issuing an AD to revise AD 95-11-15. This AD retains the actions of AD 
95-11-15, but only for those gliders with the automatic elevator 
connection incorporated. Accomplishment of the actions of this AD would 
be required in accordance with Alexander Schleicher ASK 21 Technical 
Note No. 22, dated November 26, 1990.

Cost Impact

    The FAA estimates that 35 gliders in the U.S. registry will be 
affected by this AD, that it will take approximately 1 workhour per 
glider to accomplish the required action, and that the average labor 
rate is approximately $60 per work hour. Parts cost approximately $45 
per glider. Based on these figures, the cost impact of this AD on U.S. 
operators is estimated to be $3,675, or $105 per glider. This figure is 
based upon the presumption that no affected glider owner/operator has 
accomplished the required replacement.
    Alexander Schleicher has informed the FAA that improved design 
parallel rockers have been distributed for all 35 affected gliders. 
Presuming that each set of parts has been installed on one of the 
affected gliders, the required action will not impose any cost impact 
upon U.S. operators.

The Direct Final Rule Procedure

    The FAA anticipates that this regulation will not result in adverse 
or negative comment and therefore is issuing it as a direct final rule. 
This AD restricts the glider applicability in that it only requires the 
actions on Alexander Schleicher Model ASK 21 gliders that are equipped 
with the automatic elevator connection instead of all gliders as 
required by 95-11-15. With this in mind, this AD reduces the burden 
that is currently required for U.S. operators of the affected gliders. 
Therefore, this action does not impose a significant burden on affected 
operators. In accordance with Section 11.17 of the Federal Aviation 
Regulations (14 CFR 11.17) unless a written adverse or negative 
comment, or a written notice of intent to submit an adverse or negative 
comment, is received within the comment period, the regulation will 
become effective on the date specified above. After the close of the 
comment period, the FAA will publish a document in the Federal Register 
indicating that no adverse or negative comments were received and 
confirming the date on which the final rule will become effective. If 
the FAA does receive, within the comment period, a written adverse or 
negative comment, or written notice of intent to submit such a comment, 
a document withdrawing the direct final rule will be published in the 
Federal Register, and a notice of proposed rulemaking may be published 
with a new comment period.

Comments Invited

    Although this action is in the form of a final rule and was not 
preceded by notice and an opportunity for public comment, comments are 
invited on this rule. Interested persons are invited to comment on this 
rule by submitting such written data, views, or arguments as they may 
desire. Communications shall identify the Rules Docket number and be 
submitted in triplicate to the address specified under the caption 
ADDRESSES. All communications received on or before the closing date 
for comments will be considered, and this rule may be amended in light 
of the comments received. Factual information that supports the 
commenter's ideas and suggestions is extremely helpful in evaluating 
the effectiveness of the AD action and determining whether additional 
rulemaking action would be needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket No. 91-CE-25-AD.'' The postcard will be date stamped and 
returned to the commenter.

Regulatory Impact

    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is noncontroversial and 
unlikely to result in adverse or negative comments. For reasons 
discussed in the preamble, I certify that this regulation (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 final 
evaluation has been prepared for this action and is contained in the 
Rules Docket. A copy of it may be obtained from the Rules Docket at the 
location provided under the caption ADDRESSES.

[[Page 20144]]

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to 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. Section 39.13 is amended by removing Airworthiness Directive 
(AD) 95-11-15, Amendment 39-9248 (60 FR 29978, June 7, 1995), and by 
adding a new AD to read as follows:

95-11-15 R1  Alexander Schleicher Segelflugzeugbau: Amendment 39-
11149; Docket No. 91-CE-25-AD; Revises AD 95-11-15, Amendment 39-
9248.
    Applicability: The following serial numbered Model ASK 21 
gliders, certificated in any category:

--Serial numbers 21206 through 21473; and
--Any earlier serial numbers that were retrofitted to incorporate an 
automatic elevator connection.

    Note 1: Alexander Schleicher Technical Note No. 11 includes all 
the procedures necessary to retrofit the earlier serial numbered 
Model ASK 21 gliders.
    Note 2: This AD applies to each glider 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 gliders 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 the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated in the body of this AD, unless 
already accomplished (compliance with AD 95-11-15).
    To prevent possible loss of elevator control that could result 
from a broken parallel rocker, accomplish the following:
    (a) Within 30 calendar days after July 14, 1995 (the effective 
date of AD 95-11-15), accomplish the following:
    (1) Replace the parallel rocker with an improved and stronger 
part (part number 99.000.4940 with modification status 1), in 
accordance with the instructions in Alexander Schleicher ASK 21 
Technical Note No. 22, dated November 26, 1990.
    (2) Incorporate the flight manual revisions included with the 
technical note referenced above into the aircraft flight manual 
(AFM).
    (b) As of the effective date of this AD, no person may install, 
on any affected glider, a parallel rocker that is not part number 
99.000.4940 with modification status 1.
    (c) Accomplishment of the AFM insertion, as required by 
paragraph (a)(2) of this AD, may be performed by the owner/operator 
holding at least a private pilot certificate as authorized by 
section 43.7 of the Federal Aviation Regulations (14 CFR 43.7), and 
must be entered into the aircraft records showing compliance with 
this AD in accordance with section 43.9 of the Federal Aviation 
Regulations (14 CFR 43.9).
    (d) 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 glider to a location where the 
requirements of this AD can be accomplished.
    (e) An alternative method of compliance or adjustment of the 
compliance times that provides an equivalent level of safety may be 
used if approved by the Manager, Small Airplane Directorate, FAA, 
1201 Walnut, suite 900, Kansas City, Missouri 64106.
    (1) 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.
    (2) Alternative methods of compliance approved in accordance 
with AD 95-11-15 are considered approved for this AD.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Small Airplane Directorate.
    (f) The replacement required by this AD shall be done in 
accordance with Alexander Schleicher ASK 21 Technical Note No. 22, 
dated November 26, 1990. The incorporation by reference was 
previously approved by the Director of the Federal Register in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51 as of July 14, 
1995 (60 FR 29978, June 7, 1995). Copies may be obtained from 
Alexander Schleicher GmbH & Co., Segelflugzeugbau, Postfach 60, 
36163 Poppenhausen, Germany. Copies may be inspected at the FAA, 
Central Region, Office of the Regional Counsel, Room 1558, 601 E. 
12th Street, Kansas City, Missouri, or at the Office of the Federal 
Register, 800 North Capitol Street, NW, suite 700, Washington, DC.
    (g) This amendment becomes effective on July 25, 1999. Issued in 
Kansas City, Missouri, on April 19, 1999.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-10313 Filed 4-23-99; 8:45 am]
BILLING CODE 4910-13-U

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