This document transmits Revision 1 of Non-Modification Service Bulletin TAY-72-A1775. Document History Non-Modification Service Bulletin Revision Status Initial Issue Sep.11/12 Non-Modification Service Bulletin Revision 1
Remove Incorporate Reason for change Pages 1 to 8 of the Non-Modification Service Bulletin. To include minor wording corrections in the Reason.**Printed in Great Britain** Sep.12/12

TAY SERIES PROPULSION SYSTEM SERVICE BULLETIN



# ALERT TAY−72−A1775 Transmittal - Page 1 of 1 

# ALERT1. Planning Information A. Effectivity (1) Fokker 70. Tay 620-15/20 Engines. For Engine Serial Numbers 17054, 17085, 17088, 17107 and 17166. Modules M01100AA and M01100AB (LP Compressor Module).
B. Reason There has been a reported instance of a multiple fan blade off on a Tay 620-15/20 engine. R The operator of the engine has two aircraft operated with Tay 620-15/20 engines. The operating instructions define limitations to prevent stresses caused by fan flutter that could otherwise cause crack initiation in the root of the Low Pressure (LP) compressor (fan) blades. To minimise the potential for further occurrences in the event that the operating instructions have not been previously fully adhered to, this Non-Modification Service Bulletin provides an instruction for inspecting the LP compressor (fan) blades. Revision 1 of this Service Bulletin has been issued to include minor wording corrections in the Reason. R R C. Description This Non-Modification Service Bulletin introduces an ultrasonic inspection to determine if the fan blades are cracked as a result of increased stresses resulting from a previous fan flutter event. D. Compliance
ALERT This Non-Modification Service Bulletin must be accomplished on all engines before next flight and be repeated 1250 +/- 250 flight hours. E. Approval The technical content of this document is approved under the authority of EASA Design Organisation Approval No. EASA.21J.065. ENGINE - LOW PRESSURE (LP) COMPRESSOR ROTOR BLADES - ULTRASONIC INSPECTION OF THE LP COMPRESSOR (FAN) BLADE ROOTS - NON-MODIFICATION SERVICE BULLETIN**Printed in Great Britain**



# TAY−72−A1775 Page 1 of 8 Sep.11/12 Sep.12/12 Revision 1F. Manpower Estimated Man-hours: (1) In Service 4 hours. (2) At Overhaul/Shop Visit Not applicable. G. Material Price and Availability Not applicable. H. Tooling Price and Availability New tools are not required. I. Industry Support Information
None. J. Weight and Balance (1) Weight Change
None. (2) Moment Arm No effect. (3) Datum ES2540 (PPS100). K. Electrical Load Data The aircraft electrical load is not affected by this Non-Modification Service Bulletin. L. Software Accomplishment Summary Not applicable.**Printed in Great Britain**



# TAY−72−A1775 Page 2 of 8 Sep.11/12 Sep.12/12 Revision 1M. References (1) Aircraft Maintenance Manual, Chapters 72-00-31 and 72-31-12. N. Other Publications Affected
None.**Printed in Great Britain**



# TAY−72−A1775 Page 3 of 8 Sep.11/12 Sep.12/12 Revision 12. Material Information A. Parts to be replaced
None. B. Expendable Parts
None. C. Instruction/Disposition Codes
None.**Printed in Great Britain**



# TAY−72−A1775 Page 4 of 8 Sep.11/12 Sep.12/12 Revision 13. Accomplishment Instruction A. General
NOTE : In order to reduce the potential for multiple-engine in-flight shutdown, power loss, or other anomaly due to maintenance error, Rolls-Royce Deutschland recommends that Operators avoid performing maintenance on multiple engines installed on the same aircraft at the same time. If it is not possible to avoid maintenance on more than one engine at the same time, Rolls-Royce Deutschland recommends that additional controls are applied in order to ensure that maintenance tasks have been completed as defined.
WARNING : YOU MUST BE CAREFUL WHEN YOU WORK ON THE ENGINE COMPONENTS AFTER THE ENGINE IS STOPPED. THE ENGINE COMPONENTS CAN STAY HOT FOR ALMOST ONE HOUR.
WARNING : YOU MUST NOT TOUCH HOT PARTS WITHOUT APPLICABLE GLOVES. HOT PARTS CAN CAUSE AN INJURY. IF YOU GET AN INJURY PUT IT IN COLD WATER FOR 10 MINUTES AND GET MEDICAL AID. (1) Obey all the WARNINGS and CAUTIONS in the procedures that are referred to. (2) Consumable Materials (a) Refer to the related Manual tasks given in this instruction. (3) Tools and Equipment (a) Refer to the related Manual tasks given in this instruction. B. Get access to the Low Pressure (LP) compressor (fan) blades. C. Remove the complete set of LP compressor (fan) blades from the engine (Refer to the Aircraft Maintenance Manual, Chapter 72-31-12, TASK 72-31-12-000-814).**Printed in Great Britain**



# TAY−72−A1775 Page 5 of 8 Sep.11/12 Sep.12/12 Revision 1D. Examine the LP compressor (fan) blades (1) Examine the LP compressor (fan) blades for general condition (Refer to the Aircraft Maintenance Manual, Chapter 72-31-12, TASK 72-31-12-220-816). (2) Do an ultrasonic inspection on the LP compressor (fan) blades (Refer to the Aircraft Maintenance Manual, Chapter 72-31-12, TASK 72-31-12-270-816)
NOTE : Rolls-Royce Deutschland Ltd & Co KG, Service Engineering, must be informed of the results of the inspection. (a) If there is a LP compressor (fan) blade that shows signs of cracks, the complete set of LP compressor (fan) blades including the LP compressor (fan) disk must be rejected and returned to Rolls-Royce Deutschland Ltd & Co KG. continue with step E. (b) If the LP compressor rotor blades show no signs of cracks, the complete LP compressor (fan) blade set can be re-installed on the engine. Continue with step F. E. Replace the LP compressor (fan) disk from the engine (1) Remove the LP compressor (fan) disk from the engine (Refer to the Aircraft Maintenance Manual, Chapter 72-00-31, TASK 72-00-31-000-814). (2) Install a replacement LP compressor (fan) disk on the engine (Refer to the Aircraft Maintenance Manual, Chapter 72-00-31, TASK 72-00-31-400-814). F. Install a complete set of replacement LP compressor (fan) blades on the engine (Refer to the Aircraft Maintenance Manual, Chapter 72-31-12, TASK 72-31-12-400-824). G. Complete the Accomplishment Form on pages 7 and 8 and send it to Rolls-Royce Deutschland, Service Engineering. H. A record of accomplishment is required. Rolls-Royce Deutschland suggests to put an entry into the engine log book.**Printed in Great Britain**



# TAY−72−A1775 Page 6 of 8 Sep.11/12 Sep.12/12 Revision 1Accomplishment Form (Sheet 1 of 2)**Printed in Great Britain**



# TAY−72−A1775 Page 7 of 8 Sep.11/12 Sep.12/12 Revision 1Accomplishment Form (Sheet 2 of 2)**Printed in Great Britain**



# TAY−72−A1775 Page 8 of 8 Sep.11/12 Sep.12/12 Revision 1

# S ERVICE BULLETIN FEEDBACK FORM

Sep

. 12 / 12 Revision 1 © Rolls

- Royce Deutschland Ltd & Co KG TAY

- 72

- A1775 Page 1 of 1 Printed in Great Britain Please use this form to give feedback on the quality of this Service Bulletin. The input you provide will be used to analyse areas of improvement and to take action to further improvement on the quality of our Service Bulletins. We thank you for the tim e you spent in completing this form. Please rate on a scale of 1 to 5, with 5 being the highest score:

- General quality rating of this Service Bulletin  1  2  3  4  5

- Quality rating of the Accomplishment Instruction s  1  2  3  4  5

- Quality rating of the Illustration  1  2  3  4  5

- Is this Service Bulletin easy to understand ?  Yes  No If you have had difficulties to per form this Service Bulletin please quote below the area(s) and give a short description of the issue:

Operator: Overhaul Site: Name/Title: Date: Please send the completed Service Bulletin Feedback Form to Rolls
- Royce Deutschland, Service Bulletin Group. Email: mailto:RRD.SERVICE.BULLETINS@ROLLS
- ROYCE .COM

Planning Information Section: Material Information Section: Accomplishment Instruction Section:  1.A.  1.I.  2.A.  General  1.B.  1.J.  2.B.  Get Access  1.C.  1.K.  2.C.  Removal/Installation  1.D.  1.L.  2.D.  Inspection  1.E.  1.M.  2.E.  Test  1.F.  1.N.  2.F.  Close the Access  1.G.  1.O.  Log Book Entry  1.H  1.P. Explanatory notes: