[Federal Register Volume 63, Number 107 (Thursday, June 4, 1998)]
[Rules and Regulations]
[Pages 30372-30373]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-14618]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-CE-09-AD; Amendment 39-10561; AD 98-12-04]
RIN 2120-AA64


Airworthiness Directives; Glaser-Dirks Flugzeugbau GmbH Model DG-
500M Gliders

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 Glaser-Dirks Flugzeugbau GmbH (Glaser-Dirks) Model DG-
500M gliders. This AD requires installing a rudder gap seal and 
modifying the cooling liquid reservoir mount. 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 rudder vibrations caused by flow separation at 
the rudder gap, which could result in flutter with consequent loss of 
rudder control.

DATES: Effective July 21, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of July 21, 1998.

ADDRESSES: Service information that applies to this AD may be obtained 
from DG Flugzeugbau GmbH, Postfach 4120, D-76625 Bruchsal 4, Germany; 
telephone: +49 7257-89-0; facsimile: +49 7257-8922. This information 
may also be examined at the Federal Aviation Administration (FAA), 
Central Region, Office of the Regional Counsel, Attention: Rules Docket 
No. 98-CE-09-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, 
Small Airplane Directorate, Aircraft Certification Service, FAA, 1201 
Walnut, suite 900, Kansas City, Missouri 64106; telephone: (816) 426-
6934; facsimile: (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Events Leading to the Issuance of This AD

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to include an AD that would apply to all Glaser-Dirks 
Model DG-500M gliders was published in the Federal Register as a notice 
of proposed rulemaking (NPRM) on March 20, 1998 (63 FR 13581). The NPRM 
proposed to require installing a rudder gap seal and modifying the 
cooling liquid reservoir mount. Accomplishment of the proposed 
installation as specified in the NPRM would be required in accordance 
with the maintenance manual. Accomplishment of the proposed 
modification to the cooling liquid reservoir mount as specified in the 
NPRM would be required in accordance with Glaser-Dirks Working 
Instruction No. 1 for TN 843/5, dated November 5, 1992, as referenced 
in Glaser-Dirks TN No. 843/5, dated November 30, 1992.
    The NPRM was the result of mandatory continuing airworthiness 
information (MCAI) issued by the airworthiness authority for Germany.
    Interested persons have been 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

    After careful review of all available information related to the 
subject presented above, the FAA has determined that air safety and the 
public interest require the adoption of the rule as proposed except for 
minor editorial corrections. The FAA has determined that these minor 
corrections will not change the meaning of the AD and will not add any 
additional burden upon the public than was already proposed.

Compliance Time of This AD

    Although the rudder vibrations identified in this AD occur during 
flight, this unsafe condition is not a result of the number of times 
the glider is operated. The chance of this situation occurring is the 
same for a glider with 10 hours time-in-service (TIS) as it is for a 
glider with 500 hours TIS. For this reason, the FAA has determined that 
a compliance based on calendar time should be utilized in this AD in 
order to assure that the unsafe condition is addressed on all gliders 
in a reasonable time period.

Cost Impact

    The FAA estimates that 5 gliders in the U.S. registry will be 
affected by this AD, that it will take approximately 4 workhours per 
glider to accomplish this action, and that the average labor rate is 
approximately $60 an hour. Parts cost approximately $40 per glider. 
Based on these figures, the total cost impact of

[[Page 30373]]

this AD on U.S. operators is estimated to be $1,400, or $280 per 
glider.

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 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, 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:

98-12-04  Glaser-Dirks Flugzeugbau GmbH: Amendment 39-10561; Docket 
No. 98-CE-09-AD.

    Applicability: Model DG-500M gliders, all serial numbers, 
certificated in any category.

    Note 1: 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 (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.

    Compliance: Required within the next 3 calendar months after the 
effective date of this AD, unless already accomplished.
    To prevent rudder vibrations caused by flow separation at the 
rudder gap, which could result in flutter with consequent loss of 
rudder control, accomplish the following:
    (a) Install a rudder gap seal in accordance with the 
instructions in the maintenance manual, as referenced in Glaser-
Dirks Technical Note (TN) No. 843/5, dated November 30, 1992.
    (b) Modify the cooling liquid reservoir mount in accordance with 
Glaser-Dirks Working Instruction No. 1 for TN 843/5, dated November 
5, 1992, as referenced in Glaser-Dirks TN No. 843/5, dated November 
30, 1992.
    (c) Special flight permits may be issued in accordance with 
Secs. 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.
    (d) 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.

    (e) Questions or technical information related to Glaser-Dirks 
Technical Note No. 843/5, dated November 30, 1992, should be 
directed to DG Flugzeugbau GmbH, Postfach 4120, D-76625 Bruchsal 4, 
Germany; telephone: +49 7257-89-0; facsimile: +49 7257-8922. 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.
    (f) The modification required by this AD shall be done in 
accordance with Glaser-Dirks Working Instruction No. 1 for Technical 
Note 843/5, dated November 5, 1992, as referenced in Glaser-Dirks 
Technical Note No. 843/5, dated November 30, 1992. 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 DG Flugzeugbau GmbH, Postfach 4120, 
D-76625 Bruchsal 4, 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 93-010, 
dated January 5, 1993.

    (g) This amendment becomes effective on July 21, 1998.

    Issued in Kansas City, Missouri, on May 26, 1998.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 98-14618 Filed 6-3-98; 8:45 am]
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