[Federal Register Volume 62, Number 244 (Friday, December 19, 1997)]
[Proposed Rules]
[Pages 66560-66561]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-33144]


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Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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Federal Register / Vol. 62, No. 244 / Friday, December 19, 1997 / 
Proposed Rules

[[Page 66560]]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-CE-107-AD]
RIN 2120-AA64


Airworthiness Directives; Alexander Schleicher Segelflugzeugbau 
Model ASK-21 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 Alexander Schleicher Segelflugzeugbau 
(Alexander Schleicher) Model ASK-21 sailplanes. The proposed AD would 
require replacing any tow release cable assembly that does not have a 
swivel-type end with a cable assembly that does have a swivel-type end. 
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 
inability to release the tow rope because of the design of the cable 
assembly, which could result in loss of control of the sailplane during 
towing operations.

DATES: Comments must be received on or before January 19, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 97-CE-107-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 Alexander Schleicher Segelflugzeugbau, 6416 Poppenhausen, 
Wasserkuppe, Federal Republic of Germany; telephone: 49.6658.890 or 
49.6658.8920; facsimile: 49.6658.8923 or 49.6658.8940. This information 
also may be examined at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. J. Mike Kiesov, Project Officer, 
Sailplanes/Gliders, Small Airplane Directorate, Aircraft Certification 
Service, FAA, 1201 Walnut, suite 900, Kansas City, Missouri 64106; 
telephone (816) 426-6932; 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. 97-CE-107-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. 97-CE-107-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 
certain Alexander Schleicher Model ASK-21 sailplanes. The LBA reports 
that service difficulty reports indicate that the tow release cable 
creates loops over time. The loops are relatively short and lead to 
strong bending loads on the cable, mainly at the binding clamp. The 
original design of the tow release cable does not consist of a swivel-
type end.
    This condition, if not corrected, could result in the inability to 
release the tow rope with consequent loss of control of the sailplane 
during towing operations.

Relevant Service Information

    Alexander Schleicher has issued Technical Note No. 10, dated 
October 10, 1983, which specifies procedures for replacing any tow 
release cable assembly that does not have a swivel-type end with a tow 
release cable assembly that does have a swivel-type end.
    The LBA classified this service bulletin as mandatory and issued 
German AD No. 84-2, dated January 13, 1984, 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 
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 Alexander Schleicher Model ASK-21 sailplanes 
of the same type design registered in the United

[[Page 66561]]

States, the FAA is proposing AD action. The proposed AD would require 
replacing any tow release cable assembly that does not have a swivel-
type end with a tow release cable assembly that does have a swivel-type 
end. Accomplishment of the proposed installation would be in accordance 
with the technical note previously referenced.

Cost Impact

    The FAA estimates that 30 sailplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 2 
workhours per sailplane to accomplish the proposed replacement, and 
that the average labor rate is approximately $60 an hour. Parts cost 
approximately $20 per sailplane. Based on these figures, the total cost 
impact of the proposed AD on U.S. operators is estimated to be $4,200, 
or $140 per sailplane.

Compliance Time of the Proposed AD

    Although the loops that form in the cable assembly would only occur 
during flight over time and the bending loads are related to sailplane 
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 loops could form in the tow release cable 
assembly on a sailplane with 10 hours TIS, but not form until 500 hours 
TIS on another sailplane. 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 unsafe condition is addressed on all 
sailplanes in a reasonable time period.

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:

    Alexander Schleicher Segelflugzeugbau: Docket No. 97-CE-107-AD.

    Applicability: Model ASK-21 sailplanes, serial numbers 21-001 
through 21-196, certificated in any category, that are equipped with 
a tow release cable assembly that does not have a swivel-type end.

    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 inability to release the tow rope because of the 
design of the cable assembly, which could result in loss of control 
of the sailplane during towing operations, accomplish the following:
    (a) Replace any tow release cable assembly that does not have a 
swivel-type end with a tow release cable assembly that does have a 
swivel-type end in accordance with Alexander Schleicher Technical 
Note No. 10, dated October 10, 1983.
    (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 Alexander 
Schleicher Technical Note No. 10, dated October 10, 1983, should be 
directed to Alexander Schleicher Segelflugzeugbau, 6416 
Poppenhausen, Wasserkuppe, Federal Republic of Germany; telephone: 
49.6658.890 or 49.6658.8920; facsimile: 49.6658.8923 or 
49.6658.8940. This service information may be examined at the FAA, 
Central Region, Office of the Regional Counsel, Room 1558, 601 E. 
12th Street, Kansas City.

    Note 3: The subject of this AD is addressed in German AD No. 84-
2, dated January 13, 1984.

    Issued in Kansas City, Missouri, on December 11, 1997.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 97-33144 Filed 12-18-97; 8:45 am]
BILLING CODE 4910-13-U