EASA AD No : 2009-0193R1 

EASA Form 110 Page 1/2 

 

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2009- 0193R1 

Date: 01 December 2009 

Note: This Airworthiness Directive (AD) is issued by EASA, acting in accordance with 

Regulation (EC) No 216/2008 on behalf of the European Community, its Member States 

and of the European third countries that participate in the activities of EASA under Article 

66 of that Regulation. 

This AD is issued in accordance with EC 1702/2003, Part 21A.3B. In accordance with EC 2042/2003 Annex I, Part M.A.301, the 

continuing airworthiness of an aircraft shall be ensured by accomplishing any applicable ADs. Consequently, no person may 

operate an aircraft to which an Airworthiness Directive applies, except in accordance with the requirements of that Airworthiness 

Directive unless otherwise specified by the Agency [EC 2042/2003 Annex I, Part M.A.303] or agreed with the Authority of the 

State of Registry [EC 216/2008, Article 14(4) exemption]. 

Type Approval Holder’s Name : 

Thielert Aircraft Engines GmbH 

Type/Model designation(s) : 

TAE125-01 piston engines 

TCDS Number : EASA E.055 

Foreign AD : Not applicable 

Revision: This AD revises AD 2009-0193 dated 27 August 2009 

ATA 61 Propellers/Propulsion - Vibration Isolator of the Propeller’s 

Constant Speed Unit - Inspection/Replacement 

Manufacturer(s): Thielert Aircraft Engines GmbH. 

Applicability: All TAE125-01 engines that are installed on Diamond Aircraft Industries 

DA 42 aeroplanes. 

Remark: TAE125-01 engines installed on other aeroplane types are not 

concerned by this AD. 

Reason: Engine In-Flight Shutdown (IFSD) incidents have been reported on 

Diamond Aircraft Industries DA 42 aeroplanes equipped with TAE125 

engines. The investigations showed that it was mainly the result of failure 

of the Proportional Pressure Reducing Valve (also known as Propeller 

Control Valve) due to high vibrations. 

To address this subject, AD 2008-0145 was issued in July 2008 and 

amended by its revision 1 in July 2009 to mandate a life-limit for the 

Proportional Pressure Reducing Valve (PPRV). 

Since the release of AD 2008-0145, the engine gearbox has been 

identified as the primary source of vibrations for the PPRV, and it has also 

been determined that failure of the electrical connection to the 

Proportional Pressure Reducing Valve can have contributed to some 

power loss events or IFSD. 

For the reasons described above, AD 2009-0193, which superseded AD 

2008-0145 & AD 2008-0145R1, mandated installation of a vibration 

isolator between the engine gearbox and the propeller Constant Speed 

Unit (CSU). In addition, it required an inspection of the electrical 
EASA AD No : 2009-0193R1 

EASA Form 110 Page 2/2 

 

connectors of the PPRV. Installation of the vibration isolator entails the 

replacement of the de-icing nozzle support bracket and replacement of the 

CSU aluminium pipe with a flexible hose. 

This AD 2009-0193R1 specifies compliance time limit and refers to the 

latest revision of Thielert applicable Service Bulletin (SB). In addition to 

that, this AD gives credit for Inspection/Replacement done in accordance 

with the initial issue of the SB. 

Effective Date: 15 December 2009 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated unless previously accomplished: 

1. Within 55 Flight Hours after the effective date of this AD, at the next 

inspection but no later than 28 February 2010, inspect and/or replace 

the electrical connectors of the Proportional Pressure Reducing Valve 

and install a vibration isolator between the engine gearbox and the 

propeller’s Constant Speed Unit as instructed in steps 1 to 27 of the 

Thielert Service Bulletin TM TAE 125-0020 Rev. 1. 

Note 1: If not already been done, step 22 of the Thielert Service Bulletin 

TM TAE 125-0020 calls for the initial replacement of the PPRV in 

accordance with Thielert Service Bulletin TM TAE 125-0018 revision 1. 

Note 2: The vibration isolator and the PPRV are part of the gearbox 

assembly. They must be inspected regularly in accordance with the 

Engine Operation & Maintenance Manual OM-02-01 and the Engine 

Repair Manual RM-02-01. 

2. Inspection/Replacement done in accordance with TM TAE 125-0020 

and annexes, initial issue dated 20 August 2009 are acceptable for 

compliance with the requirements of this AD. 

Ref. Publications: Thielert Service Bulletin TM TAE 125-0020 and annexes, Revision 1 

dated 25 November 2009; 

Thielert Service Bulletin TM TAE 125-0018 revision 1 dated 12 November 

2008; 

The use of later approved revisions of these documents is acceptable for 

compliance with the requirements of this AD. 

Remarks : 1. If requested and appropriately substantiated, EASA can approve 

Alternative Methods of Compliance for this AD. 

2. The required actions and the risk allowance have granted the 

issuance of a Final AD with Request for Comments, postponing the 

public consultation process after publication. 

3. Enquiries regarding this AD should be referred to the Airworthiness 

Directives, Safety Management & Research Section, Certification 

Directorate, EASA. E-mail ADs@easa.europa.eu 

4. For any question concerning the technical content of the requirements 

in this AD, please contact: 

Thielert Aircraft Engines 

Platanenstraße 14 

D-09350 Lichtenstein, Germany 

Telephone +49-37204-696-0 Fax +49-37204-696-55 

E-mail info@centurion-engines.com