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## EASA AIRWORTHINESS DIRECTIVE

AD No.: 2007-0223 R2

Date: 26 October 2007

No person may operate an aircraft to which an Airworthi ness Directive applies, except in accordance with the requirements of that Airworthiness Directive unless otherwi se agreed with the Authority of the State of Registry. 

### Type Approval Holder’s Name :
Dowty Propellers Type/Model designation(s) :

R408 series propellers

TCDS Number: EASA P.002

Foreign AD: Not applicable

Revision: This Airworthiness Directive (AD) revises EASA AD 2007-0223R1 dated 04 October 2007.



### ATA 61 Propellers - Blades Metallic Leading Edge Guard - Inspection

Manufacturer(s): Dowty Propellers

Applicability: All R408/6-123-F/17 propellers equipped with blade assemblies Part Number (P/N) 697071200-18, 697071210-18, 697071227-18, 697071240- 18, 697071245-18 and 697071257-18, where the bonded metallic leading edge guard has accumulated 1 200 Flight Hours (FH) or less since installation.
These propellers are known to be installed on, but not limited to, Bombardier Inc. (formerly de Havilla nd Canada) Models DHC-8-400, DHC8-401 and DHC-8-402.

Reason: Three in-service propellers have been found to have blades which have lost the bonded metallic leading edge guard. If the leading edge guard comes off as the propeller turns, it could cause secondary damage to aircraft or injury to personnel. For the re asons described above, EASA issued Emergency AD 2007-0223-E to require repetitive inspections of the blade Leading Edge (L/E) guards for correct bonding until they accumulate more than 1 200 FH time in service. Revision 1 of this AD was issued to clarify the required inspections and follow-up actions depending on findings and to make reference to the latest Dowty Alert Service Bulletin (ASB) revision.

This AD has been further revised for cl arification, specifying that blades repaired at the tip are only allowed to continue up to 500 hours in service after repair. This limitation was alre ady in the Dowty ASB and the Note is added to the AD to avoid the impressi on that the AD does not require the same limitation.

Effective Date: 17 August 2007

### 2/2 Compliance: Required as indicated, unless accomplished previously: (1) Within the next 50 FH or within 1 month after the effective date of this AD, whichever occurs first, inspec t all the concerned blade assemblies where the bonded metallic L/E guard has accumulated 1 200 FH or less since installation, in accordan ce with the instructions of Dowty Propellers ASB No. D8400-61-A69; (2) Within 50 FH or 1 month after installing a replacement blade, inspect the concerned blade assembly where the bonded metallic L/E guard has accumulated 1 200 FH or less since installation, in accordance with the instructions of Dowt y Propellers ASB No. D8400-61-A69; (3) After the inspection as required by paragraph (1) or (2) of this AD, as applicable, at intervals not to exceed 100 FH, repeat the inspection of the concerned blade assemblies in accordance with the instructions of Dowty Propellers ASB No. D8400- 61-A69 until the bonded blade L/E guard has accumulated more than 1 200 FH since installation; (4) When, during any of the inspections as required by paragraphs (1), (2) or (3) of this AD, disbonding is found, apply the criteria as indicated in Appendix A of Dowty Propellers ASB No. D8400-61-A69 Revision 1 and, within the associated time period, repair or replace the affected blade assembly, as necessary, in acco rdance with the instructions of Dowty Propellers ASB No. D8 400-61-A69 Revision 1.

Note: Blades that have been repaired with in the first 101,6 mm (4.0 inches) of the tip of the blade as specified in Appendix D of the referenced ASB are allowed to continue in service for an other 500 FH after accomplishment of the repair. Repair does not terminate the repetitive inspection requirements of paragraph (3) of this directive.

Ref. Publications: Dowty Propellers Alert Service Bulletin No. D8400-61-A69 initial issue dated 15 August 2007 or Revision 1 dated 18 September 2007, or later approved revisions.

Remarks: 1. If requested and appro priately substantiated, EASA can accept Alternative Methods of Compliance for this AD. 2. The safety assessment has requested not to implement the full consultation process and an immedi ate publication and notification. 3. Enquiries regarding this AD should be addressed to the AD Focal Point, Certification Directorate, EASA - E-mail: ADs@easa.europa.eu
4. For any questions concerning the te chnical 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 716000 - Fax +44 (0) 1452 716001 e-mail mtowkan@dap.dowty.com