DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0911; Product Identifier 2017-CE-025-AD; Amendment
39-19121; AD 2017-25-07]
RIN 2120-AA64

Airworthiness Directives; Alexander Schleicher GmbH & Co.
Segelflugzeugbau Gliders

AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for all
Alexander Schleicher GmbH & Co. Segelflugzeugbau Models ASH 25M and ASH
26E gliders. This AD results from mandatory continuing airworthiness
information (MCAI) issued by an aviation authority of another country
to identify and correct an unsafe condition on an aviation product. The
MCAI describes the unsafe condition as fatigue cracks found on the
exhaust silencer. We are issuing this AD to require actions to address
the unsafe condition on these products.

DATES: This AD is effective January 18, 2018.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of January 18,
2018.

ADDRESSES: You may examine the AD docket on the internet at http://www.
regulations.gov by searching for and locating Docket No. FAA-2017-
0911; or in person at Document Management Facility, U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
For service information identified in this AD, contact Alexander
Schleicher GmbH & Co. Segelflugzeugbau, Alexander-Schleicher-Str. 1, D-
36163 Poppenhausen, Germany; phone: +49 (0) 06658 89-0; fax: +49 (0)
06658 89-40; internet: http://www.alexander-schleicher.de; email:
info@alexander-schleicher.de. You may view this referenced service
information at the FAA, Policy and Innovation Division, 901 Locust,
Kansas City, Missouri 64106. For information on the availability of
this material at the FAA, call (816) 329-4148. It is also available on
the internet at http://www.regulations.gov by searching for Docket No.
FAA-2017-0911.

FOR FURTHER INFORMATION CONTACT: Jim Rutherford, Aerospace Engineer,
FAA, Small Airplane Standards Branch, 901 Locust, Room 301, Kansas
City, Missouri 64106; telephone: (816) 329-4165; fax: (816) 329-4090;
email: jim.rutherford@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 by adding an AD that would apply to all Alexander Schleicher
GmbH & Co. Segelflugzeugbau Models ASH 25M and ASH 26E gliders. The
NPRM was published in the Federal Register on September 22, 2017 (82 FR
44361). The NPRM proposed to correct an unsafe condition for the
specified products and was based on mandatory continuing airworthiness
information (MCAI) originated by an aviation authority of another
country. The MCAI states:

Occurrences were reported of finding cracks on exhaust silencer
part number (P/N) 800.65.0001, installed on ASK 21 Mi powered
sailplanes. Subsequent investigation determined that the affected
part is susceptible to fatigue cracking and is also installed on
other Schleicher powered sailplanes.
This condition, if not corrected, could lead to heat damage in
the engine compartment and to the engine installation, possibly
resulting in reduced control of the powered sailplane.
To address this potentially unsafe condition, Schleicher issued
Technical Note (TN) ASK 21 Mi No. 11, TN ASW 22 BLE 50R No. 16, TN
ASH 25 M/Mi No. 32 and TN ASH 26 E No. 19 (single document,
hereafter referred to as `the TN' in this [EASA] AD), to provide
replacement instructions.
For the reasons described above, this [EASA] AD requires
replacement of the affected exhaust silencer with an improved part
and introduces installation restrictions of a part with P/N
800.65.0001].

The MCAI can be found in the AD docket on the internet at https://www.regulations.gov/document?D=FAA-2017-0911-0002.

Comments

We gave the public the opportunity to participate in developing
this AD. We received no comments on the NPRM or on the determination of
the cost to the public.

Conclusion

We reviewed the relevant data and determined that air safety and
the public interest require adopting this AD as proposed except for
minor editorial changes. We have determined that these minor changes:

Are consistent with the intent that was proposed in the
NPRM for correcting the unsafe condition; and
Do not add any additional burden upon the public than was
already proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

We reviewed Alexander Schleicher GmbH & Co. Segelflugzeugbau ASK 21
Mi Technical Note No. 11, ASW 22 BLE 50R Technical Note No. 16, ASH 25
M/Mi Technical Note No. 32, ASH 26 E Technical Note No. 19 (single
document), dated January 8, 2016. The service information describes
procedures for replacing the exhaust silencer with an improved part.
This service information is reasonably available because the interested
parties have access to it through their normal course of business or by
the means identified in the ADDRESSES section of this AD.

Costs of Compliance

We estimate that this AD will affect 35 products of U.S. registry.
We also estimate that it will take about 8 work-hours per product to
comply with the basic requirements of this AD. The average labor rate
is $85 per work-hour. Required parts will cost about $3,900 per
product.
Based on these figures, we estimate the cost of this AD on U.S.
operators to be $160,300, or $4,580 per product.
We have no way of determining the number of products that have an
affected exhaust silencer, part number 800.65.0001, installed that will
need to be replaced. Therefore, this cost estimate includes all
affected gliders on the U.S. registry.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. ``Subtitle VII: Aviation
Programs,'' describes in more detail the scope of the Agency's
authority.
We are issuing this rulemaking under the authority described in
``Subtitle VII, Part A, Subpart III, section 44701: General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on products identified in this
rulemaking action.
This AD is issued in accordance with authority delegated by the
Executive Director, Aircraft Certification Service, as authorized by
FAA Order 8000.51C. In accordance with that order, issuance of ADs is
normally a function of the Compliance and Airworthiness Division, but
during this transition period, the Executive Director has delegated the
authority to issue ADs applicable to small airplanes, gliders, and
domestic business jet transport airplanes to the Director of the Policy
and Innovation Division.

Regulatory Findings

We determined that this AD will not have federalism implications
under Executive Order 13132. This AD will not have a substantial direct
effect 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.
For the reasons discussed above, I certify this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866,
(2) Is not a ``significant rule'' under the DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979),
(3) Will not affect intrastate aviation in Alaska, and
(4) 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.

Examining the AD Docket

You may examine the AD docket on the internet at http://www.regulations.
gov by searching for and locating Docket No. FAA-2017-
0911; or in person at the Docket Management Facility between 9 a.m. and
5 p.m., Monday through Friday, except Federal holidays. The AD docket
contains the NPRM, the regulatory evaluation, any comments received,
and other information. The street address for the Docket Office
(telephone (800) 647-5527) is in the ADDRESSES section. Comments will
be available in the AD docket shortly after receipt.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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. The FAA amends Sec. 39.13 by adding the following new AD: