[Federal Register Volume 64, Number 79 (Monday, April 26, 1999)]
[Proposed Rules]
[Pages 20230-20232]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-10312]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-CE-06-AD]
RIN 2120-AA64


Airworthiness Directives; Alexander Schleicher Segelflugzeugbau 
Model ASH 26E Sailplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to supersede Airworthiness Directive 
(AD) 98-09-09, which currently requires replacing the internal cooling 
air fan with a fan that incorporates a white impeller on all Alexander 
Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASH 26E 
sailplanes. The proposed AD would require inspecting the internal 
cooling air fan for damage, and replacing any fan that does not 
incorporate a black impeller with a fan that incorporates a black 
impeller either immediately or at a certain time period, 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 failure of the internal cooling 
system air fan caused by a certain design configuration of the 
impeller, which could cause the engine to overheat with possible engine 
failure.

DATES: Comments must be received on or before June 8, 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-06-

[[Page 20231]]

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. 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) 426-6932; 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. 99-CE-06-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-06-AD, Room 1558, 601 E. 12th Street, Kansas 
City, Missouri 64106.

Discussion

    AD 98-09-09, Amendment 39-10489 (63 FR 20308, April 24, 1998), 
currently requires replacing the internal cooling air fan with a fan 
that incorporates a white impeller, part number (P/N) R1K059, on all 
Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASH 
26E sailplanes. Accomplishment of that action is required in accordance 
with Alexander Schleicher Technical Note No. 1, dated October 31, 1996; 
and Mid-West Engines Ltd. Service Bulletin No. 001, dated October 5, 
1996.
    AD 98-09-09 was a result of a report from the Luftfahrt-Bundesamt 
(LBA), which is the airworthiness authority for Germany, that the 
impeller of the internal cooling air fan on the above-referenced 
sailplanes could slip and result in a reduction of pressure in the 
internal cooling system. The higher internal temperatures that will 
follow could cause the engine to overheat with possible engine failure.

Actions Since Issuance of Previous Rule

    The LBA recently notified the FAA that an unsafe condition may 
exist on these Alexander Schleicher Model ASH 26E sailplanes. The LBA 
advises that the internal cooling air fan installed on the affected 
sailplanes as required by AD 98-09-09 incorporates a white impeller, P/
N R1K059. This type of impeller was installed in one of the affected 
airplanes that had an in-flight malfunction. Research of this 
malfunction reveals that the design of the white impeller is not 
adequate and an improved design impeller should be installed.
    This condition, if not corrected in a timely manner, could cause 
the engine to overheat with possible engine failure.

Relevant Service Information

    Alexander Schleicher has issued Technical Note No. 5, dated July 
23, 1998, which specifies procedures for inspecting the internal 
cooling air fan for damage. Mid-West Service Bulletin No. 02, dated 
November 13, 1997, includes procedures for replacing any fan that does 
not incorporate a black impeller, P/N R1K074, with a fan that 
incorporates a P/N R1K074 impeller.
    The LBA classified this service bulletin as mandatory and issued 
German AD 1998-391, dated October 8, 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 develop in other Alexander Schleicher ASH 26E sailplanes of 
the same type design registered in the United States, the FAA is 
proposing AD action to supersede AD 98-09-09. The proposed AD would 
require inspecting the internal cooling air fan for damage, and 
replacing any fan that does not incorporate a black impeller, P/N 
R1K074, with a fan that incorporates a P/N R1K074 impeller. The 
replacement would be accomplished either immediately or at a certain 
time period, depending on the results of the inspection.
    Accomplishment of the proposed action would be required in 
accordance with the service information previously referenced.

Differences Between the Service Bulletin, the German AD, and This 
Proposed AD

    Alexander Schleicher Technical Note No. 5, dated July 23, 1998, 
specifies inspecting the internal air cooling air fan prior to further 
flight, and German AD 1998-391, dated October 8, 1998, requires this 
inspection prior to further flight on sailplanes registered in Germany.
    The FAA does not have justification to require this inspection 
prior to further flight. The FAA is proposing this inspection ``within 
the next 30 calendar days after the effective date of the AD.'' The FAA 
is proposing the replacement ``within the next 9 calendar months after 
the effective date of the AD'', or if damage is found during the 
inspection, ``prior to further flight.''

Compliance Time of the Proposed AD

    Although a damaged impeller blade is only unsafe while the affected 
sailplanes are in flight, the condition could occur at any time. For 
example, damage could occur on one sailplane with 25 hours time-in-
service (TIS)

[[Page 20232]]

while not occurring on another until 250 hours TIS. This is due to 
different usage levels and the various ways sailplanes are operated and 
utilized. In addition, the average monthly usage of the affected 
sailplane ranges throughout the fleet. For example, one owner may 
operate the sailplane 25 hours TIS in one week, while another operator 
may operate the sailplane 25 hours TIS in one year. In order to assure 
that the unsafe condition is detected and corrected on all affected 
sailplanes in a timely manner without inadvertently grounding any 
affected sailplane, the FAA is proposing compliance based on calendar 
time instead of hours TIS.

Cost Impact

    The FAA estimates that 9 sailplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 14 
workhours per sailplane to accomplish the proposed AD, and that the 
average labor rate is approximately $60 an hour. Parts are available 
from the manufacturer at no cost. Based on these figures, the total 
cost impact of the proposed AD on U.S. operators is estimated to be 
$7,560, or $840 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 removing Airworthiness Directive 
(AD) 98-09-09, Amendment 39-10489 (63 FR 20308, April 24, 1998), and by 
adding a new airworthiness directive (AD) to read as follows:

Alexander Schleicher Segelflugzeugbau: Docket No. 99-CE-06-AD.
    Applicability: Model ASH 26E sailplanes, all serial numbers, 
certificated in any category; that are equipped with an internal 
cooling system air fan that does not incorporate a black impeller, 
part number (P/N) R1K074.

    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 (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 failure of the internal cooling system air fan caused 
by a certain design configuration of the impeller, which could cause 
the engine to overheat with possible engine failure, accomplish the 
following:
    (a) Within the next 30 calendar days after the effective date of 
this AD, inspect the internal cooling air fan for damage in 
accordance with Alexander Schleicher Technical Note No. 5, dated 
July 23, 1998.
    (b) Replace the internal cooling system air fan with a fan that 
incorporates a black impeller, P/N R1K074, at whichever of the 
compliance times below (paragraphs (b)(1) and (b)(2) of this AD) 
that applies. Accomplish this replacement in accordance with Mid-
West Service Bulletin No. 02, dated November 13, 1997:
    (1) Prior to further flight if damage is found in the internal 
cooling air fan during the inspection required by paragraph (a) of 
this AD; or
    (2) Within the next 9 calendar months after the effective date 
of this AD if damage is not found during the inspection required by 
paragraph (a) of this AD.
    (c) As of the effective date of this AD, no person may install, 
on any affected sailplane, an internal cooling system air fan that 
does not incorporate a black impeller, P/N R1K074, as specified in 
Mid-West Service Bulletin No. 02, dated November 13, 1997; and 
Alexander Schleicher Technical Note No. 5, dated July 23, 1998.
    (d) 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.
    (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 Alexander 
Schleicher Technical Note No. 5, dated July 23, 1998, should be 
directed to Alexander Schleicher Segelflugzeugbau, 6416 
Poppenhausen, Wasserkuppe, Federal Republic of Germany. 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-
391, dated October 8, 1998.

    Issued in Kansas City, Missouri, on April 19, 1999.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-10312 Filed 4-23-99; 8:45 am]
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