[Federal Register Volume 63, Number 225 (Monday, November 23, 1998)]
[Rules and Regulations]
[Pages 64600-64602]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-30895]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-CE-103-AD; Amendment 39-10896; AD 98-24-10]
RIN 2120-AA64


Airworthiness Directives; Stemme GmbH & Co. KG Model S10 
Sailplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to certain Stemme GmbH & Co. KG (Stemme) Model S10 sailplanes. 
This AD requires replacing the flap drive rocker, part number (P/N) 
10SW-RMW, with a modified flap drive rocker. This AD is the result of 
mandatory continuing airworthiness information (MCAI) issued by the 
airworthiness authority for Germany. The actions specified by this AD 
are intended to prevent failure of the flap drive rocker caused by the 
design of the original part, which could result in loss of lateral 
control and wing flap control with consequent reduced and/or loss of 
sailplane control.

DATES: Effective December 9, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of December 9, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before December 16, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket 98-CE-103-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.
    Service information that applies to this AD may be obtained from 
Stemme GmbH & Co. KG, Gustav-Meyer-Allee 25, D-13355 Berlin, Germany; 
telephone: 49.33.41.31.11.70; facsimile: 49.33.41.31.11.73. This 
information may also be examined at the Federal Aviation Administration 
(FAA), Central Region, Office of the Regional Counsel, Attention: Rules 
Docket 98-CE-103-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) 426-6934; facsimile: (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Discussion

    The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority 
for Germany, recently notified the FAA that an unsafe condition may 
exist on certain Stemme Model S10 sailplanes. The LBA reports that the 
flap drive rocker, P/N 10SW-RMW, is likely to fail due to fatigue. This 
was revealed following failure of a different part in the flight 
control system. The manufacturer then performed an analysis on other 
critical points, which revealed the flap drive rocker condition.
    This condition, if not corrected, could result in failure of the 
flap drive rocker and loss of lateral control and wing flap control 
with consequent reduced and/or loss of sailplane control.

Relevant Service Information

    Stemme has issued Service Bulletin No. A31-10-017, Amendment-Index 
02.a, dated May 20, 1998, which specifies procedures for replacing the 
flap drive rocker, P/N 10SW-RMW, with a modified P/N 10SW-RMW flap 
drive rocker. This service bulletin also specifies obtaining this 
modified part from the manufacturer.
    The LBA classified this service bulletin as mandatory and issued 
German AD 1998-324, dated July 30, 1998, in order to assure the 
continued airworthiness of these sailplanes in Germany.

The FAA's Determination

    This sailplane model is manufactured in Germany 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 LBA has kept the FAA informed of 
the situation described above.
    The FAA has examined the findings of the LBA; 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 This AD

    Since an unsafe condition has been identified that is likely to 
exist or develop in other Stemme Model S10 sailplanes of the same type 
design, the FAA is issuing an AD. This AD requires replacing the flap 
drive rocker, P/N 10SW-RMW, with a modified P/N 10SW-RMW flap drive 
rocker. The actions are to be done in accordance with Stemme Service 
Bulletin No. A31-10-017, Amendment-Index 02.a, dated May 20, 1998.

Cost Impact

    None of the Stemme Model S10 sailplanes affected by this action are 
on the U.S. Register. All sailplanes included in the applicability of 
this rule currently are operated by non-U.S. operators under foreign 
registry; therefore, they are not directly affected by this AD action. 
However, the FAA considers this rule necessary to ensure that the 
unsafe condition is addressed in the event that any of these subject 
sailplanes are imported and placed on the U.S. Register.
    Should an affected sailplane be imported and placed on the U.S. 
Register, accomplishment of the required action would take 
approximately 5 workhours at an average labor rate of $60 per workhour. 
Parts cost approximately $200 per sailplane. Based on these figures, 
the total cost impact of this AD would be

[[Page 64601]]

$500 per sailplane that would become registered in the United States.

The Effective Date of This AD

    Since this AD action does not affect any sailplane that is 
currently on the U.S. register, it has no adverse economic impact and 
imposes no additional burden on any person. Therefore, notice and 
public procedures hereon are unnecessary and the amendment may be made 
effective in less than 30 days after publication in the Federal 
Register.

Comments Invited

    Although this action is in the form of a final rule and was not 
preceded by notice and 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. 98-CE-103-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.
    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 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, 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 adding a new airworthiness directive 
(AD) to read as follows:

98-24-10 STEMME GMBH & CO. KG: Amendment 39-10896; Docket No. 98-CE-
103-AD.

    Applicability: Model S10 sailplanes, serial numbers 10-03 
through 10-26, 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 (c) 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.
    To prevent failure of the flap drive rocker caused by the design 
of the original part, which could result in loss of lateral control 
and wing flap control with consequent reduced and/or loss of 
sailplane control, accomplish the following:
    (a) Prior to further flight after the effective date of this AD, 
replace the flap drive rocker, part number (P/N) 10SW-RMW, with a 
modified flap drive rocker, in accordance with Stemme Installation 
Instruction No. A34-10-017-E, Amendment-Index 01.a, dated August 10, 
1998, as referenced in Stemme Service Bulletin No. A31-10-017, 
Amendment-Index 02.a, dated May 20, 1998.
    (b) 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.
    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an equivalent level of safety may be 
approved by the Manager, Small Airplane Directorate, 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.

    (d) Questions or technical information related to Stemme Service 
Bulletin No. A31-10-017, Amendment-Index 02.a, dated May 20, 1998, 
should be directed to Stemme GmbH & Co. KG, Gustav-Meyer-Allee 25, 
D-13355 Berlin, Germany; telephone: 49.33.41.31.11.70; facsimile: 
49.33.41.31.11.73. 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.
    (e) The replacement required by this AD shall be done in 
accordance with Stemme Installation Instruction No. A34-10-017-E, 
Amendment-Index 01.a, dated August 10, 1998, as referenced in Stemme 
Service Bulletin No. A31-10-017, Amendment-Index 02.a, dated May 20, 
1998. This incorporation by reference was approved by the Director 
of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR 
part 51. Copies may be obtained from Stemme GmbH & Co. KG, Gustav-
Meyer-Allee 25, D-13355 Berlin, 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.

    Note 3: The subject of this AD is addressed in German AD 1998-
324, dated July 30, 1998.

    (f) This amendment becomes effective on December 9, 1998.


[[Page 64602]]


    Issued in Kansas City, Missouri, on November 10, 1998.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 98-30895 Filed 11-20-98; 8:45 am]
BILLING CODE 4910-13-U