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[Federal Register Volume 63, Number 110 (Tuesday, June 9, 1998)]
[Proposed Rules]
[Pages 31375-31377]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-15197]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-CE-12-AD]
RIN 2120-AA64

Airworthiness Directives; Glaser-Dirks Flugzeugbau GmbH Model DG-
400 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 certain Glaser-Dirks Flugzeugbau GmbH (Glaser-
Dirks) Model DG-400 gliders. The proposed action would require 
inspecting the powerplant mount and the propeller mount for any loose 
parts. If parts are loose, the proposed AD would require immediately 
modifying the starter motor, retrofitting the holder for the starter 
motor, and checking the engine ignition timing. If parts are not found 
loose, the proposed AD would require modifying the starter motor, 
retrofitting the holder for the starter motor, and checking the engine 
ignition timing at a later time. 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 damage to the engine caused by 
vibration, which could result in loss of engine power during critical 
phases of flight.

DATES: Comments must be received on or before July 17, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region,

[[Page 31376]]

Office of the Regional Counsel, Attention: Rules Docket No. 98-CE-12-
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, Im Schollengarten 19-20, 7520 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: Mike Kiesov, Aerospace Engineer, FAA, 
Small Airplane Directorate, Aircraft Certification Service, 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-12-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-12-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 Glaser-Dirks Model DG-400 gliders. The LBA reports 
that several of these gliders have lost engine power during flight. 
Further investigation revealed that the powerplant propeller mount was 
not secure on some engines. This problem related back to the engine 
manufacturer not drilling the rear mount holes deep enough on the 
propeller mount to hold it securely during engine vibration.
    These conditions, if not corrected, could result in the propeller 
mount and powerplant mount coming loose during critical phases of 
flight.

Relevant Service Information

    DG Flugzeugbau has issued Technical Note Nr. 826/22 dated January 
10, 1990, which specifies procedures for inspecting for loose parts on 
the powerplant and propeller mount and inserting revised pages into the 
maintenance manual. If any part is found loose, the service information 
specifies procedures for modifying the starter motor, retrofitting the 
holder of the starter motor, and checking the engine timing.
    The LBA classified this service bulletin as mandatory and issued 
German AD 90-43, dated February 26, 1990, 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-400 gliders of the same 
type design registered in the United States, the FAA is proposing AD 
action.
    The proposed AD would require inspecting the powerplant mount and 
the propeller mount for loose parts. If any parts are loose, the 
proposed AD would require modifying the starter motor, retrofitting the 
holder for the starter motor, checking the engine ignition timing, and 
adjusting the timing if necessary.
    Accomplishment of the proposed action would be in accordance with 
DG Flugzeugbau Technical Note Nr. 826/22, dated January 10, 1990.

Differences Between the Service Information and the Proposed AD

    The manufacturer's service information specifies procedures for 
inspecting the powerplant mount for a secure, tight condition prior to 
every flight. This service information also specifies inserting revised 
pages to the maintenance manual.
    The proposed AD would not require an inspection prior to each 
flight, and would not require inserting revised pages to the 
maintenance manual. The FAA will insert a ``NOTE'' into the body of the 
proposed AD, recommending inserting the revised pages into the 
maintenance manual.

Cost Impact

    The FAA estimates that 35 gliders in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 4 
workhours per airplane to accomplish the proposed action, and that the 
average labor rate is approximately $60 an hour. Parts cost 
approximately $150 per airplane. Based on these figures, the total cost 
impact of the proposed AD on U.S. operators is estimated to be $13,650, 
or $390 per glider.

Proposed Compliance Time

    The compliance time of the proposed AD is in calendar time instead 
of hours time-in-service (TIS). The average monthly usage of the 
affected glider ranges throughout the fleet. For example, one owner may 
operate the glider 25 hours TIS in one week, while another operator may 
operate the glider 25 hours TIS in one year. In order to ensure that 
all of the owners/operators of the affected glider have inspected the 
powerplant and propeller mounts for loose parts within a reasonable 
amount of time, the FAA is proposing a calendar compliance time.

Regulatory Impact

    The regulations proposed herein would not have substantial direct 
effects on the States, on the relationship

[[Page 31377]]

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-12-AD. 
Applicability: Model DG-400 gliders, serial numbers 4-1 through 4-
249, 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 (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 1 calendar month after the effective 
date of this AD, unless already accomplished.
    To prevent damage to the engine caused by vibration, which could 
result in loss of engine power during critical phases of flight, 
accomplish the following:
    (a) Inspect the powerplant (engine) mount and propeller mount 
for any loose parts in accordance with paragraph 1 in the 
Instructions section of Glaser-Dirks Technical Note (TN) Nr. 826/22, 
dated January 10, 1990.
    (1) If any part of the powerplant mount or propeller mount is 
found loose, prior to further flight, accomplish paragraphs 2 
through 4 in the Instructions section of Glaser-Dirks TN Nr. 826/22, 
dated January 10, 1990. The engine ignition timing procedures shall 
be accomplished in accordance with the appropriate Bombardier ROTAX 
maintenance manual for ROTAX engine type 505, which is referenced in 
Working Instruction No. 3, Instruction 4 of the Glaser-Dirks TN Nr. 
826/22.
    (2) If no part of the powerplant mount or propeller mount is 
loose upon the inspection required in paragraph (a) of this AD, 
accomplish paragraphs 2 through 4 in the Instructions section of 
Glaser-Dirks TN Nr. 826/22, dated January 10, 1990, within the next 
3 calendar months after the date of the initial inspection.

    Note 2: It is recommended that the manual pages referenced in 
the Instructions section of Glaser-Dirks TN Nr. 826/22 be inserted 
into the maintenance manual.
    (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 glider 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 3: 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 DG Flugzeugbau 
Technical Note No. 826/22, dated January 10, 1990, should be 
directed to DG Flugzeugbau GmbH, P.O. Box 4120, 76625 Bruchsal, 
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 4: The subject of this AD is addressed in German AD 90-43 
Glaser-Dirks, dated February 26, 1990.

    Issued in Kansas City, Missouri, on June 1, 1998.
Ronald K. Rathgeber,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-15197 Filed 6-8-98; 8:45 am]
BILLING CODE 4910-13-U
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