[Federal Register Volume 64, Number 79 (Monday, April 26, 1999)]
[Proposed Rules]
[Pages 20229-20230]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-10311]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-CE-07-AD]
RIN 2120-AA64


Airworthiness Directives; Stemme GmbH & Co. KG Model S10-VT 
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 certain Stemme GmbH & Co. KG (Stemme) Model 
S10-VT sailplanes. The proposed AD would require modifying the 
wastegate control in order to eliminate heat damage. The proposed AD is 
the result of mandatory continuing airworthiness information (MCAI) 
issued by the airworthiness authority for Germany. The actions 
specified by the proposed AD are intended to prevent the wastegate 
control from malfunctioning because of heat damage, which could result 
in loss of automatic manifold pressure control and engine damage.

DATES: Comments 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. 99-CE-07-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 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 also may be examined at the Rules Docket at the 
address above.

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:

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 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-07-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-07-AD, Room 1558, 601 E. 12th Street, Kansas 
City, Missouri 64106.

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-VT sailplanes. The LBA reports 
instances of heat damage to the wastegate control cable with one 
malfunction of the wastegate control. This caused damage in the 
turbocharger pressure oil tubes and their mountings.
    This condition, if not corrected in a timely manner, could result 
in loss of automatic manifold pressure control and engine damage.

Relevant Service Information

    Stemme has issued Service Bulletin No. A31-10-034, Amendment 01.a, 
pages 3 and 4, dated July 24, 1998, which specifies procedures for 
modifying the wastegate control in order to eliminate heat damage.
    The LBA classified this service bulletin as mandatory and issued 
German AD 1998-400, dated October 22,1998, 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 the Proposed AD

    Since an unsafe condition has been identified that is likely to 
exist or

[[Page 20230]]

develop in other Stemme Model S10-VT sailplanes of the same type design 
registered in the United States, the FAA is proposing AD action. The 
proposed AD would require modifying the wastegate control in order to 
eliminate heat damage. Accomplishment of the proposed action would be 
required in accordance with the service information previously 
referenced.

Cost Impact

    The FAA estimates that 6 sailplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 4 
workhours per sailplane to accomplish the proposed action, and that the 
average labor rate is approximately $60 an hour. Parts cost 
approximately $150 per sailplane. Based on these figures, the total 
cost impact of the proposed AD on U.S. operators is estimated to be 
$2,340, or $390 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:

Stemme GMBH & Co. KG:  Docket No. 99-CE-07-AD.

Applicability: Model S10-VT sailplanes, serial numbers 11-004 
through 11-006 and 11-008 through 11-013, 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 within the next 3 calendar months after the 
effective date of this AD, unless already accomplished.
    To prevent the wastegate control from malfunctioning because of 
heat damage, which could result in loss of automatic manifold 
pressure control and engine damage, accomplish the following:
    (a) Modify the wastegate control in order to eliminate heat 
damage, in accordance with the Instructions section of Stemme 
Service Bulletin No. A31-10-034, Amendment 01.a, pages 3 and 4, 
dated July 24, 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, 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.

    (d) Questions or technical information related to Stemme Service 
Bulletin No. A31-10-034, Amendment 01.a, dated July 24, 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.

    Note 3: The subject of this AD is addressed in German AD 1998-
400, dated October 22, 1998.

    Issued in Kansas City, Missouri, on April 19, 1999.
James E. Jackson,
Acting Manager, Small Airplane Directorate,
Aircraft Certification Service.
[FR Doc. 99-10311 Filed 4-23-99; 8:45 am]
BILLING CODE 4910-13-P