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Airworthiness Directive packet

AD (number not stated)

Airworthiness Directives; Thielert Aircraft Engines GmbH Reciprocating Engines

1 · Quick read — prepared by AircraftDirectives

Our plain-language summary — not the regulation

Requires replacing the existing rail pressure control valve with an improved rail pressure control valve.

Federal Register document
2011-33514
Citation
76 FR 82110
Amendment
39-16906
Docket
Docket No. FAA-2009-0948
Action
Final rule.
Published
2011-12-30
Effective
2012-02-03
Effective (as stated in the rule)
This AD is effective February 3, 2012.
Issued by
Transportation Department, Federal Aviation Administration
Regulation
14 CFR 39
Applies to (in our index)
Thielert TAE 125

2 · Official Federal Register document — government source, verbatim

Reproduced unedited from the Federal Register
[Federal Register Volume 76, Number 251 (Friday, December 30, 2011)]
[Rules and Regulations]
[Pages 82110-82111]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-33514]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0948; Directorate Identifier 2009-NE-30-AD; 
Amendment 39-16906; AD 2010-06-12R1]
RIN 2120-AA64


Airworthiness Directives; Thielert Aircraft Engines GmbH 
Reciprocating Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are revising an existing airworthiness directive (AD) for 
Thielert Aircraft Engines GmbH models TAE 125-02-99 and TAE 125-01 
reciprocating engines. That AD currently requires replacing the 
existing rail pressure control valve with an improved rail pressure 
control valve. This new AD requires the same actions but relaxes the 
initial compliance time from within 100 flight hours to within 600 
flight hours for TAE 125-01 reciprocating engines. This AD was prompted 
by the determination that our AD was inadvertently more restrictive 
than European Aviation Safety Agency AD 2008-0128. We are issuing this 
AD to prevent engine in-flight shutdown, possibly resulting in reduced 
control of the aircraft.

DATES: This AD is effective February 3, 2012.

ADDRESSES: For service information identified in this AD, contact 
Thielert Aircraft Engines GmbH, Platanenstrasse 14 D-09350, 
Lichtenstein, Germany; phone: +49-37204-696-0; fax: +49-37204-696-55; 
email: engines.com">info@centurion-engines.com. You may review copies of the 
referenced service information at the FAA, 12 New England Executive 
Park, Burlington, MA. For information on the availability of this 
material at the FAA, call (781) 238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; 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 this AD, the regulatory evaluation, 
any comments received, and other information. The address for the 
Docket Office (phone: (800) 647-5527) is 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 FURTHER INFORMATION CONTACT: Alan Strom, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; phone: (781) 238-7143; 
fax: (781) 238-7199; email: [email protected].

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to revise AD 2010-06-12, Amendment 39-16236 (75 FR 12439, March 
16, 2010). That AD applies to the specified products. The NPRM 
published in the Federal Register on October 18, 2011 (76 FR 64285). 
That NPRM proposed to require relaxing the initial compliance time from 
within 100 flight hours to within 600 flight hours for TAE 125-01 
reciprocating engines.

Comments

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

Clarification of the VRail Plug Modification

    Since we issued the NPRM, we determined that the compliance 
paragraph describing the Vrail plug modification needed clarification. 
We changed paragraph (e)(1)(i) in the AD to describe what existing 
parts need to be removed and what part number needs to be installed.

Conclusion

    We reviewed the relevant data and determined that air safety and 
the public interest require adopting the AD with the change described 
previously.

Costs of Compliance

    Based on the service information, we estimate that this AD will 
affect about 370 TAE 125-01 and TAE 125-02-99 reciprocating engines 
installed on products of U.S. registry. We also estimate that it will 
take about 1.5 work-hours per engine to comply with this AD. The 
average labor rate is $85 per work-hour. Required parts will cost about 
$500 per engine. Based on these figures, we estimate the cost of the AD 
for initial replacement on U.S. operators to be $232,175.

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

[[Page 82111]]

products identified in this rulemaking action.

Regulatory Findings

    We have 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 that this AD:
    (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),
    (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.

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

0
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]

0
2. The FAA amends Sec.  39.13 by removing airworthiness directive (AD) 
2010-06-12, Amendment 39-16236, (75 FR 12439, March 16, 2010), and 
adding the following new AD:

2010-06-12R1 Thielert Aircraft Engines GmbH: Amendment 39-16906 ; 
Docket No. FAA-2009-0948; Directorate Identifier 2009-NE-30-AD.

(a) Effective Date

    This airworthiness directive (AD) is effective February 3, 2012.

(b) Affected ADs

    This AD revises AD 2010-06-12, Amendment 39-16236 (75 FR 12439, 
March 16, 2010).

(c) Applicability

    This AD applies to Thielert Aircraft Engines GmbH (TAE) models 
TAE 125-01 and TAE 125-02-99 reciprocating engines.

(d) Reason

    This AD was prompted by the determination that our AD was 
inadvertently more restrictive than European Aviation Safety Agency 
AD 2008-0128. We are issuing this AD to prevent engine in-flight 
shutdown, possibly resulting in reduced control of the aircraft.

(e) Actions and Compliance

    Unless already done, do the following actions.

(1) TAE 125-02-99 Reciprocating Engines

    (i) For TAE 125-02-99 reciprocating engines, within 100 flight 
hours after the effective date of this AD, replace the existing rail 
pressure control valve with a rail pressure control valve P/N 05-
7320-E000702. Modify the Vrail plug by removing the two existing 
single wire sealings and installing three new single wire sealings, 
P/N AMP-828904-1.
    (ii) Guidance on the rail pressure control valve replacement and 
Vrail plug modification specified in paragraph (e)(1)(i) of this AD 
can be found in Thielert Repair Manual RM-02-02, Chapter 73-10.08, 
and Chapter 39-40.08, respectively.

(2) TAE 125-01 Reciprocating Engines

    (i) For TAE 125-01 reciprocating engines, before 600 flight 
hours time-since-new, or within 100 flight hours after the effective 
date of this AD, whichever occurs later, replace the existing rail 
pressure control valve with a rail pressure control valve, P/N 02-
7320-04100R3.
    (ii) Guidance on the rail pressure control valve replacement 
specified in paragraph (e)(2)(i) of this AD can be found in Thielert 
Repair Manual RM-02-01, Chapter 29.0.

(3) TAE 125-02-99 and TAE 125-01 Engines, Repetitive Replacements of 
Rail Pressure Control Valves

    Thereafter, for affected TAE 125-02-99 and TAE 125-01 engines, 
replace the rail pressure control valve with the same P/N valve 
within every 600 flight hours.

(f) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, FAA, may approve AMOCs 
for this AD. Use the procedures found in 14 CFR 39.19 to make your 
request.

(g) Related Information

    (1) For related information, refer to MCAI EASA AD 2008-0128, 
dated July 9, 2008, EASA AD 2008-0215, dated December 5, 2008, 
Thielert Service Bulletin No. TAE 125-1008 P1, Revision 1, dated 
September 29, 2008, and Thielert Repair Manual RM-02-02. For a copy 
of the service information referenced in this AD, contact Thielert 
Aircraft Engines GmbH, Platanenstrasse 14 D-09350, Lichtenstein, 
Germany; phone: +49-37204-696-0; fax: +49-37204-696-55; email: 
engines.com">info@centurion-engines.com.
    (2) For more information about this AD, contact Alan Strom, 
Aerospace Engineer, Engine Certification Office, FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, MA 
01803; phone: (781) 238-7143; fax: (781) 238-7199; email: 
[email protected].

(h) Material Incorporated by Reference

    None.

    Issued in Burlington, Massachusetts, on December 23, 2011.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-33514 Filed 12-29-11; 8:45 am]
BILLING CODE 4910-13-P

Sources. Section 1 is written by AircraftDirectives from the record below and is a reading aid only. Section 2 is the United States Government's own text, reproduced without edit.

Federal Register: https://www.federalregister.gov/documents/2011/12/30/2011-33514/airworthiness-directives-thielert-aircraft-engines-gmbh-reciprocating-engines

Official PDF: https://www.govinfo.gov/content/pkg/FR-2011-12-30/pdf/2011-33514.pdf

Packet generated 2026-08-18 08:13 UTC.

This packet is not an airworthiness determination and not legal or maintenance advice. AircraftDirectives reproduces official records and condenses their wording for easier reading. It does not decide, certify or imply whether any aircraft, engine, appliance or part is airworthy, compliant, affected by this directive, or eligible for return to service. No inspection, approval, or determination of any kind is performed or implied by this document.

Section 1 is a reading aid, not the rule. It is our own plain-language condensation, written to help a reader find the relevant directive quickly. It is NOT a substitute for the regulation, it may omit conditions, exceptions, compliance times, alternative methods of compliance (AMOCs) and applicability limits, and it has no legal force whatsoever. Only the official text governs. Where Section 1 and Section 2 differ in any respect, Section 2 - and the official source it was retrieved from - controls absolutely.

Responsibility remains with the owner/operator. Under 14 CFR §91.403 and §91.417 the owner or operator is responsible for maintaining airworthiness and for required records; under §39.7 no person may operate a product to which an airworthiness directive applies except in accordance with that directive. Determining applicability to a specific serial number and configuration, and performing or supervising any required action, is the responsibility of the owner/operator and appropriately certificated personnel.

Accuracy and currency. Section 2 was retrieved at the time stamped above and is reproduced without edit; Federal Register material is a work of the United States Government. Directives are amended, corrected and superseded over time, and this sheet is a snapshot, not a live record - it does not update after printing. Re-check the official sources before acting on it. This packet is provided without warranty of any kind, express or implied, including fitness for a particular purpose. We do not sell parts and have no commercial interest in any action a directive may require.

AircraftDirectives · AD 2011-33514 · Section 1 is our plain-language reading aid; Section 2 is the official Federal Register text and controls where the two differ. Not an airworthiness determination — 14 CFR §91.403 / §91.417 responsibility remains with the owner/operator. Retrieved 2026-08-18 08:13 UTC.