[Federal Register Volume 63, Number 80 (Monday, April 27, 1998)]
[Proposed Rules]
[Pages 20545-20546]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-11013]



[[Page 20545]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-CE-31-AD]
RIN 2120-AA64


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

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 Glaser-Dirks Flugzeugbau GmbH (Glaser-
Dirks) Model DG-500M gliders. The proposed AD would require inspecting 
the center of gravity (C.G.) tow release cable pulley for correct 
positioning, and replacing the C.G. tow release cable pulley with one 
made of aluminum either immediately or eventually depending on the 
results of the inspection. 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 C.G. tow release cable from coming off the 
pulley because of incorrect positioning, which could result in the 
pilot being unable to release from tow operations.

DATES: Comments must be received on or before June 1, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 98-CE-31-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 DG Flugzeugbau GmbH, Postfach 4120, D-76625 Bruchsal 4, Germany; 
telephone: +49 7257-89-0; facsimile: +49 7257-8922. This information 
also may be examined at the Rules Docket at the address above.

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:

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. 98-CE-31-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. 98-CE-31-AD, Room 1558, 601 E. 12th Street, Kansas 
City, Missouri 64106.

Discussion

    The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority 
for Germany, notified the FAA that an unsafe condition may exist on all 
Glaser-Dirks Model DG-500M gliders. The LBA reports an incident where 
the center of gravity (C.G.) tow release cable pulley on one of the 
affected gliders moved in the axial direction as the ball bearing in 
the pulley came loose.
    This condition, if not corrected in a timely manner, could result 
in the C.G. tow release cable coming off the pulley, and the pilot 
being unable to release from tow operations.

Relevant Service Information

    Glaser-Dirks has issued Technical Note No. 843-9, dated November 
21, 1997, which specifies procedures for inspecting the C.G. tow 
release cable pulley for correct positioning, and replacing the C.G. 
tow release cable pulley with one made of aluminum, part no. S 30.
    The LBA classified this service bulletin as mandatory and issued 
German AD 1998-023, dated January 15, 1998, in order to assure the 
continued airworthiness of these gliders in Germany.

The FAA's Determination

    This glider model is manufactured in Germany and is type 
certificated for operation in the United States under the provisions of 
Sec. 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 develop in other Glaser-Dirks Model DG-500M gliders of the 
same type design registered in the United States, the FAA is proposing 
AD action. The proposed AD would require inspecting the C.G. tow 
release cable pulley for correct positioning, and replacing the C.G. 
tow release cable pulley with one made of aluminum, part no. S 30, 
either immediately or eventually depending on the results of the 
inspection. Accomplishment of the proposed installation would be 
required in accordance with Glaser-Dirks Technical Note No. 843-9, 
dated November 21, 1997.

Compliance Time of the Proposed AD

    Although the C.G. tow release cable coming off the pulley would 
only be an unsafe condition during flight and would only occur after 
repeated glider operation, the FAA has no basis to determine the 
approximate number of hours time-in-service (TIS) when the unsafe 
condition is likely to occur. For example, the unsafe condition 
referenced in this proposal could occur on a glider with 10 hours TIS, 
but not occur until 500 hours TIS on another glider. For this reason, 
the FAA has determined that a compliance based on calendar time should 
be utilized in the proposed AD in order to assure that the

[[Page 20546]]

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 would be 
affected by the proposed AD, that it would take approximately 2 
workhours per glider to accomplish the proposed action, and that the 
average labor rate is approximately $60 an hour. Parts cost 
approximately $20 per glider. Based on these figures, the total cost 
impact of the proposed AD on U.S. operators is estimated to be $700, or 
$140 per glider.

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:

Glaser-Dirks Flugzeugbau GMBH: Docket No. 98-CE-31-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 (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.
    To prevent the center of gravity (C.G.) tow release cable from 
coming off the pulley because of incorrect positioning, which could 
result in the pilot being unable to release from tow operations, 
accomplish the following:
    (a) Within the next 30 calendar days after the effective date of 
this AD, inspect the C.G. tow release cable pulley for correct 
positioning in accordance with the Instructions section of Glaser-
Dirks Technical Note No. 843-9, dated November 21, 1997. If any tow 
release pulley is found out-of-center during this inspection, prior 
to further flight, replace the C.G. tow release cable pulley with 
one made of aluminum, part no. S 30. Accomplish this replacement in 
accordance with the technical note.
    (b) Within the next 6 calendar months after the effective date 
of this AD, unless already accomplished as required by paragraph (a) 
of this AD, replace the C.G. tow release cable pulley with one made 
of aluminum, part no. S 30. Accomplish this replacement in 
accordance with the Instructions section of Glaser-Dirks Technical 
Note No. 843-9, dated November 21, 1997.
    (c) The replacement required by paragraph (b) of this AD may be 
accomplished at any time prior to the required time, including in 
lieu of the inspection required by paragraph (a) of this AD.
    (d) 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.
    (e) 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.

    (f) Questions or technical information related to Glaser-Dirks 
Technical Note No. 843-9, dated November 21, 1997, 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.

    Note 3: The subject of this AD is addressed in German AD 1998-
023, dated January 15, 1998.

    Issued in Kansas City, Missouri, on April 17, 1998.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-11013 Filed 4-24-98; 8:45 am]
BILLING CODE 4910-13-U