EASA AD No.: 2011-0012 

EASA Form 110 Page 1/2 

EASA AIRWORTHINESS DIRECTIVE 

AD No.: 2011-0012 

Date: 20 January 2011 

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 AD applies, except in accordance with the requirements of that AD 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 : 

GE Aviation Systems Ltd, 

trading as Dowty Propellers 

Type/Model designation(s) : 

R212 and R251 propellers 

TCDS Number : United Kingdom (UK) 107 

Foreign AD : Not applicable 

Supersedure : This AD supersedes EASA AD 2010-0256, published on 06 December 2010. 

ATA 61 Propellers – Hub and Driving Centre Assembly – Inspection / 

Replacement 

Manufacturer(s): GE Aviation Systems Ltd, trading as Dowty Propellers (formerly Dowty Rotol 

Ltd., Dowty Aerospace Propellers, Dowty Aerospace Gloucester or Dowty 

Propellers) 

Applicability: Model R212/4-30-4/22 propellers with hub and driving centre assembly Part 

Number (P/N) 601022105, 601022211, 601022294, 601021426, 601021858, 

601021859 and Model R251/4-30-4/49 propellers with hub and driving centre 

assembly P/N 660207202 and 660207203. 

These propellers are known to be installed on, but not limited to, BAE 

Systems (formerly British Aerospace, Hawker Siddeley) HS.748 aeroplanes. 

Reason: Reports have been received from a small number of HS.748 operators of 

finding cracks in the propeller hub port buttress threads of R212 and R251 

propellers. The affected hubs had accumulated in excess of 6 000 flight 

hours. 

This condition, if not detected and corrected, could lead to propeller blade 

separation, possibly resulting in damage to the aeroplane and/or injury to 

persons on the ground. 

Initially, CAA UK issued AD 012-10-86 to require repetitive inspections and 

corrective actions as specified in the original Dowty Alert Service Bulletin 

(ASB) 61-1043. 

For the reason describe above, AD 2010-0256 superseded CAA UK AD 012-

10-86 and required repetitive Non-Destructive Testing (NDT) inspections of 

the buttress threads in the propeller hub and driving centre assembly and, 

depending on findings, replacement with serviceable parts. 
EASA AD No.: 2011-0012 

EASA Form 110 Page 2/2 

Since AD 2010-0256 was issued, ASB 61-1043 Revision 6 was published by 

Dowty Propellers. 

This AD retains the requirements of EASA AD 2010-0256, which is 

superseded, corrects the P/N’s for affected propellers models and adds new 

P/N’s of hub and driving centre assembly applicability. 

Effective Date: 03 February 2011 

Required Action(s) 

and Compliance 

Time(s): 

Required as indicated unless accomplished previously: 

(1) Within 500 flight hours (FH) after 20 December 2010 [the effective date 

of EASA AD 2010-0256] and thereafter at intervals not exceeding 500 

FH, accomplish a Non-Destructive Testing (NDT) inspection of the 

buttress threads in the propeller hub and driving centre assembly in 

accordance with the instructions of Dowty Propellers Alert Service 

Bulletin (ASB) 61-1043 at Revision 6. 

(2) If, during any inspection as required by paragraph (1) of this AD, cracks 

are detected, before next flight, replace the hub and driving centre 

assembly with a serviceable assembly in accordance with the 

accomplishment instructions from the Dowty Propellers ASB 61-1043 

Revision 6. 

(3) Replacement of the hub and driving centre assembly as required by 

paragraph (2) of this AD does not constitute terminating action for the 

repetitive inspection requirements of paragraph (1) of this AD. 

(4) From the effective date of this AD, do not install a propeller to which this 

AD applies on any aeroplane, unless the hub and driving centre 

assembly of that propeller has been inspected and, depending on 

findings, corrected in accordance with the requirements of this AD. 

Ref. Publications: Dowty Propellers ASB 61-1043 Revision 6, dated 05 January 2011. 

The use of later approved revisions of this document 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 & Request 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: 

Dowty Propellers, Anson Business Park, Cheltenham Road East, 

Gloucester GL2 9QN, United Kingdom 

Tel +44 (0) 1452 716067 – Fax +44 (0) 1452 716001 

E-mail Mike.Towkan@ge.com.