EASA AD No.: 2012-0025

EASA Form 110 Page 1/1

EASA AIRWORTHINESS DIRECTIVE

AD No.: 2012-0025

Date: 08 February 2012

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 :

Rolls-Royce plc

Type/Model designation(s) :

RB211 Trent 800 series engines

TCDS Number: United Kingdom 1051

Foreign AD: Not applicable

Supersedure: This AD supersedes EASA AD 2010-0097 dated 26 May 2010.

ATA 72 Engine – Low Pressure Compressor Fan Blades – Inspection / 

Replacement

Manufacturer(s): Rolls-Royce plc

 Applicability: RB211 Trent 895-17, 892-17, 892B-17, 884-17, 884B-17, 877-17 and 875-17 

engines, all serial numbers.

These engines are known to be installed on, but not limited to, Boeing 777 

series aeroplanes.

Reason: In January 2009, a Trent 895 powered Boeing 777-200 aeroplane experienced 

release of a Low Pressure (LP) compressor blade which had failed due to 

fatigue cracking in the root section of the blade. The released blade (undercut 

root standard) had received a part life processing to apply a compression layer 

to the blade root (Service Bulletin RB211-72-D672 - Introduction of Laser Shock 

Peening (LSP)) and also a part life upgrade to the retention feature lubrication 

system. Investigation revealed that the effectiveness of this upgraded blade root 

lubrication coating system may be reduced dependant on the extent of previous 

running with the earlier standard, leading to increased blade root stress levels.

In the specific case of the released blade, a review of its in-service modification 

history has shown that it operated for a relatively high number of flight cycles 

prior to the compression layer processing and the new retention feature 

lubrication system. A review of the Engine Health Monitoring data has also 

identified it operated at high N1 speeds compared to the Trent 800 fleet average 

N1 speeds.

The combination of these factors resulted in increased fatigue life usage which

is considered to have led to crack initiation and propagation prior to reaching the 

blade’s declared life limit. A review of all in-service undercut / LSP standard

Trent 800 LP compressor blades was done, which identified specific blades that 
EASA AD No.: 2012-0025

EASA Form 110 Page 2/2

carry a similar increased susceptibility to cracking.

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

failure, possibly resulting in release of high energy non contained debris from 

the engine.

To address this potential unsafe condition, EASA AD issued 2010-0097 to

require repetitive inspections of the affected LP compressor fan blades to detect 

possible root cracks in the undercut radius shear key slot area and, depending 

on findings, replacement of LP compressor fan blades.

Since that AD was issued, a root crack was discovered in a fan blade which was 

not predicted to crack until at a higher life. Prompted by this finding, more blades 

have been identified to be affected by this potential unsafe condition, listed by 

serial number (s/n) in Appendix 3 of Rolls Royce Non Modification Service 

Bulletin (NMSB) RB211-72-AG244 Revision 4 (hereafter referred to as the SB).

For the reasons described above, this AD retains the requirements of EASA AD 

2010-0097, which is superseded, expands the applicability by adding certain LP 

compressor fan blades listed in Appendix 3 of the SB, and reduces the 

compliance time for the initial inspection.

Effective Date: 13 February 2012

Required Action(s) 

and Compliance

Time(s):

Required as indicated, unless previously accomplished:

(1) Initially, within the compliance time specified in Table 1 of this AD, as 

applicable, and thereafter at intervals not exceeding 100 flight cycles (FC), 

inspect each affected LP compressor blade in accordance with the 

instructions of Section 3 of the SB.

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

detected in a LP compressor fan blade, before next flight, replace the 

affected LP compressor blade with a serviceable blade.

(3) Inspections and corrective actions accomplished prior to the effective date 

of this AD, in accordance with the instructions of the SB at original issue, 

Revision 1, Revision 2, or Revision 3, are acceptable to comply with the 

initial requirements of paragraphs (1) and (2) of this AD. After the effective 

date of this AD, all inspections must be accomplished in accordance with 

the instructions of the SB at Revision 4.

(4) From the effective date of this AD, do not install a LP compressor fan blade, 

identified by s/n in Appendix 3 of the SB, in any engines, unless in 

compliance with the requirements of this AD.

Table 1 – Initial Inspection Compliance Time

Affected LP compressor 

blades listed by s/n in the 

SB, Appendix number:

Initial Inspection threshold, after 

the effective date of this AD

3A and 3B 70 FC

3C Within 10 months

3D Within 22 months

3E Within 34 months

3F Within 46 months

3G Within 58 months

3H Within 70 months

3I Within 82 months

3J Within 94 months

3K Within 106 months

3L Within 118 months
EASA AD No.: 2012-0025

EASA Form 110 Page 3/3

Ref. Publications: Rolls-Royce RB211 Propulsion System NMSB RB211-72-AG244 Revision 4, 

dated 22 December 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 Safety Information

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

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

this AD, please contact:

Rolls-Royce plc., P.O. Box 31, Derby, DE24 8BJ, The United Kingdom.

Telephone: +44 (0) 1332 242424, Fax: +44 (0) 1332 249936.

Email: tech.help@rolls-royce.com or download the publication from 

https://www.aeromanager.com.