Several incidents of seizing hydraulic pump drive pulley bearings between 330-700 hours were reported for the AS350 B3 and EC130 B4 helicopters. An investigation is underway to determine the cause. As an interim measure, Eurocopter reminds technicians to comply with maintenance procedures for the new hydraulic pump drive, including inspecting the bearing every 150 hours or 12 months and checking for roughness, brinelling or noise during rotation. A service bulletin will reduce the inspection interval to 50 hours for some models. Proper maintenance of the bearing is important while the investigation continues.

1. No. 2541-S-29
SAFETY INFORMATION NOTICE
SUBJECT: HYDRAULIC POWER
New hydraulic pump drive (POST MOD 07-9566)
For the attention of
AIRCRAFT Version(s)
CONCERNED Civil Military
AS350 B, BA, BB, B1, B2, B3, D L1
AS550 A2, C2, C3, U2
EC130 B4, T2
Several incidents have been reported on AS350 B3 and EC130 B4 helicopters (between 330 and 700 hours). The
incidents were due to seizing of the hydraulic pump drive pulley bearing (POST MOD 07-9566). These incidents led
to rupture of the drive belt.
These incidents are currently undergoing investigation in order to determine the cause.
Without predicting the conclusions of these investigations, EUROCOPTER issues this Safety Information Notice, in
order to remind you that it is important to comply with the maintenance operations associated with this new
hydraulic pump drive (The Technical Documentation is currently being updated for some versions).
1. At present, the sensitive check of the bearing must be performed every 150 flying hours or 12 months, the first
limit reached is applicable (example: for version B3, refer to AMM Task 63-11-00,6-15). Only the detailed
inspection (DI) of the bearing is to be performed. The bearing must not be lubricated at this time limit.
2. Remove the belt to perform the sensitive check of the hydraulic pump drive bearing.
3. During the manual check of the bearing, perform several full turns with the bearing, in order to detect possible
rough points, brinelling or bearing noise (a "scraping" bearing can be a sign for internal damage).
4. If any doubt arises during this check, remove and replace hydraulic pump drive assembly 350A35-0132-00.
5. The re-lubrication of the bearing must be performed at 600H // 24M intervals as indicated in the MSM Task
("LUB").
EUROCOPTER informs you that a Service Bulletin will be issued in January 2013 to reduce the check interval from
150 to 50 flying hours for AS350/AS550 helicopters and introduce a check at 50 flying hours for the EC130.
Pending this, EUROCOPTER underlines that it is very important to perform the sensitive check of the bearing and
to contact the EUROCOPTER Technical Support (DynComp.Technical-Support@eurocopter.com) if you are in
doubt.
Revision 0 2012-12-24 Page 1/4
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2. No. 2541-S-29
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3. No. 2541-S-29
Extract / comment of the Task
For the hydraulic pump: DI: Detailed Inspection.
Check of the belt of the bearing:
• Belt:
o AMM Task 63-11-00, 6-2 b (Post MOD 079555)
• Bearing:
o AMM Task 63-11-00, 6-15
Visual check of the bearing,
Sensitive check of the bearing,
The bearing must not be re-lubricated at this time limit. A new bearing must not be re-
lubricated upon installation.
Revision 0 2012-12-24 Page 3/4
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4. No. 2541-S-29
Extract / comment of the Task
For the hydraulic pump: RIG: Rigging
DI: Detailed Inspection
LUB: LUBrication
Check of the belt of the bearing:
• Belt:
o AMM Task 63-11-00, 6-2 b (Post MOD 079555)
• Bearing:
o AMM Task 63-11-00, 6-15
Visual check of the bearing,
Sensitive check of the bearing,
The bearing must be re-lubricated at this time limit.
Revision 0 2012-12-24 Page 4/4
This document is available on the internet: www.eurocopter.com/techpub