FROM : AIRBUS CUSTOMER SERVICES TOULOUSE

ALL OPERATORS TELEX - ALL OPERATORS TELEX SUBJECT: ATA29 - HYDRAULIC POWER - Inspection of electrical feeder cables and Green hydraulic system electrical motor pump pressure hoses at frame 54, for Eaton (formerly Vickers) configuration.
OUR REF: AOT A310 - 29A2101 Rev 01 dated 12 April 2011 OUR PREVIOUS REF: AOT A310 - 29A2101 dated 09 November 2010
0.REASON FOR REVISION The purpose of this AOT revision is to inform operators that: . It is anticipated that an EAS A Airworthiness Directive (AD) will render this AOT inspection mandatory. . The in - flight use of the Green EMPs is forbidden and will have to be highlighted by a locally manufactured placard to be installed in the cockpit with recording in the log book. Th is is applicable until the AOT ́s requirement for inspection (and repair, if necessary) is completed. .Due to AOT ́s reported findings, additional inspections, underneath the clamps securing the electrical conduits, are requested. Accomplishment of this rev ision is also necessary on aircraft having already been inspected as per previous AOT issue. The revised paragraphs are indicated by: **BEG.REV** and **END.REV**.
1.AIRCRAFT AFFECTED All A310 - 200/
- 300 aircraft equipped with Eaton (Formerly Vickers) Hyd raulic Electrical Motor Pump (EMP) models.
2.REFERENCED DOCUMENTATION REF.1: Airbus Service Information Letter (SIL) N° 29

- 047 (Rev 01 February 1993). REF.2: Airbus Modification N° 10017 S20254 (Prevent chafing between electrical conduits and Green EMP FIN 11GE hydraulic pressure hose). REF.3: Airbus mandatory Service Bulletin (SB) A310 - 29 - 2036 (Rev 03 June 2006). REF.4: IPC 29 - 21 - 03 Figure 1 (Green EMP installation - Pre REF 2 Airbus Modification and pre - REF.3 Airbus SB). REF.5: IPC 29 - 21 - 03 Figure 1C ( Green EMP installation - Post REF 2 Airbus Modification or post - REF.3 Airbus SB).REF.6: IPC 24 - 92 - 03 Figure 17 (Green EMP electric feeder cable

installation at Frame 54 zone 147). REF.7: AMM 20 - 23 - 11 Paragraph 7.Permitted damage and defects on flexible hy draulic hoses. REF.8: ESPM 20 - 53 - 21 Repair of standard cables (Damage check and repair procedures). REF.9: ESPM 20 - 53 - 31 Repair of convoluted conduits (Damage check and repair procedures). **BEG.REV** REF.10: AOT A310 - 29A2102 dated 12 April 2011 for simila r one time visual inspection of the Parker (formerly Abex) installation condition.
3.REASON 3.1 FACTS While preparing the aircraft, an A310 - 300 equipped with Eaton (formerly Vickers) Green EMPs, for towing from the hangar, the two Green EMPs were select ed ON to close the MLG Doors. Then when the Green/Blue and Green/Yellow Power Transfer Units (PTUs) were selected ON to retract the Flaps/Slats, a large hydraulic haze (sprayed fluid) with a burnt electrical smell came from the LH MLG wheel well bay. The e lectrical aircraft network was switched off. The left hand forward side area of the belly fairing was covered with hydraulic spray while the equipment, electrical harnesses and connectors showed signs of high temperature exposure. The leak was coming from the Green EMP FIN 11GE pressure line with insulation damage on one cable of the electrical feeder cables for Green EMP FIN 12GE, in the area of the hydraulic leak. As the leak and cable insulation damage are the only visible evidences, it is supposed that hydraulic spray combined with possible electrical arcing might be the source of the reported damage. This aircraft was delivered early 1993 with the REF.2 Airbus Modification embodied. This Modification was issued to avoid past event of chafing between ele ctrical conduits and hydraulic pressure hose. 3.2 CONSEQUENCES Due to the proximity of both the Green EMP hydraulic pressure hose and electrical feeder cables, if damage occurs to the feeder cable with, at the same time, leakage at the hydraulic pressure hose, it might result in the reported event. 3.3 AIM This AOT is to request:- Installation of a locally manufactured placard in the cockpit

forbidding the in - flight use of the Green EMPs,

- Recording in the logbook of this requirement to not operate the Green EMPs in flight,

- A one - time visual inspection to verify the correct installation and condition (With repair if necessary) of . The hydraulic pressure hoses (REF.4 or REF.5 IPC figure), . The electrical conduits, feeder cables (REF.6 IPC figure), . T he associated clamping devices at Frame 54 as well as the electrical conduits, feeder cables (REF.6 IPC figure) underneath the clamps. This requires removal of the concerned clamps, This is applicable to all A310 - 200 /
- 300 with Eaton (formerly Vickers) E MP models fitted, whatever their installation configuration i.e. with or without the REF 2 Airbus Modification and / or REF 3 Airbus SB embodied.
4.SHORT TERM ACTION 4.1 PLANNING AND MANPOWER The AOT ́s requirements described in paragraph 4.2 have to be carried out at the next convenient opportunity e.g. during a night stop, . Within 15 calendar days from the issue date of the AOT Rev 01 for installation in the cockpit of a locally manufactured placard forbidding the in - flight use of the Green EMPs, with recording in the logbook, . Within 500 FH or 4 months whichever comes first, from the issue date of the AOT Rev 01 for the inspection and repair, if necessary. The estimated manpower for inspection without findings is about 2.00 hours.

- It is anticipated that this AOT will be rendered mandatory by an EASA Airworthiness Directive (AD). 4.2 AOT ́s REQUIREMENTS a) INSTALLATION IN THE COCKPIT OF A LOCALLY MANUFACTURED SELF - ADHESIVE PLACARD WITH RECORDING IN THE LOGBOOK (1) Install on the "HYD PWR" overhead pan el 427VU, a locally manufactured self - adhesive placard forbidding the in - flight use of the Green EMPs (P/BSW FIN 14GE - "ELEC PUMPS"). As a proposal, the placard could be as follows: . With the below wording and letters of about 2 to 3 mm height on a self adhesive placard size of 45 mm width and 10 mm height, DO NOT USE GREEN ELEC PUMPS IN FLIGHT . With placard installed on or above the "ELEC PUMPS" push button switch of "HYD PWR" overhead panel 427VU, (2) Make an entry in the logbook to record, as per ab ove placard, thatthe

in - flight use of the Green EMPs is forbidden. Also mention that this limitation is applicable until AOT ́s requirement for inspection (and repair, if necessary) is completed as per AOT ́s paragraph 4.2.b). Once AOT ́s requirement is comp leted (inspection and repair, if necessary), remove the placard from the cockpit and clear the associated logbook entry. b) INSPECTION / REPAIR / REPLACEMENT (1) Preparation for the inspection / replacement procedure

- Make sure that the aircraft is elect rically grounded (AMM 24 - 00 - 00 Page Block 301).

- De - energize the aircraft electrical circuits (AMM 24 - 41 - 00 Page Block 301).

- Open the LH main landing gear (MLG) door (AMM 32 - 12 - 11 Page Block 301).

- Put the access platform in position in zone 147.

- Dep ressurize the Green hydraulic system (AMM 29 - 10 - 00 Page Block 301). (2) Inspection / replacement procedure With reference to REF.3 Airbus SB (Figures on pages 13, 14 and 15) reflecting the two possible in - service installation configurations of the Green E MP hydraulic pressure hoses, electrical conduits and feeder cables, perform the following inspection with repair and/or replacement if required: *For aircraft of pre - REF.2 Airbus Modification and pre REF 3 Airbus SB configuration, identified as "BEFORE" o n REF.3 Airbus SB (Figures on pages 13 and 15) and reflected also on REF.4 IPC figure,

- Inspect at "C" location (Figure page 15 "BEFORE" configuration), the clamps, the electrical conduits, the feeder cables and the hydraulic

press ure hoses for correct condition and installation.

o Remove clamps securing the electrical conduits (Figure page 15 "BEFORE" configuration), check condition of the clamping device as well as of the electri cal conduits to ensure there are no damage,

- If damage is found on the electrical conduits, check the condition of the electrical feeder cables,

- If chafing marks or damage beyond allowable limits are apparent replace or repair the affected parts (Hydraulic pressure hoses,Electrical conduits, feeder cables, clamps). o For permissible damage and defects on hydraulic hoses, see REF 7 AMM procedure.

o For repair of electrical conduit and feeder cable, see REF 8 and REF.9 ESPM procedures.

- If not already done, install on the upper hydraulic pressure hose length (Green EMP FIN 11GE) a spiralex band (Spiral trip) ref

NSA849000T125 as per REF.1 Airbus SIL or apply the REF.3 Airbus SB. Make sure that the installation is in accordance with REF.3 Airbus SB "BEFORE" configuration (Figures on pages 13 and 15) and REF.4 IPC figure. For information , REF.3 Airbus SB was mandated by EASA AD N° 2006 - 0285R1

dated November 13, 2006. *For aircraft of post - REF.2 Airbus Modification or post - REF.3 Airbus SB configuration, identified as "AFTER" on REF.3 Airbus SB (Figures on pages 14 and 15) and refl ected on REF.5 IPC figure,

- Inspect at "C" location (Figure page 15 "AFTER" configuration), the clamps, the spacer, the electrical conduits, the feeder cables and hydraulic pressure hoses for correct condition and installation. o Remove clamps securing the electrical conduits (Figure page 15 "AFTER" configuration), check condition of the clamping device as well as of the electrical conduits to ensure there are no damage,

- If damage is found on the electrical conduits, check the condition of the electrical feeder cables,

- If chafing marks or damage beyond allowable limits are apparent replace or repair the affected parts (Hoses, Ele ctrical conduits,

feeder cables, clamps, spacer).

o For permissible damage and defects on hydraulic hoses, see REF 7 AMM procedure.o For repair of electrical conduit and feeder cable,

see REF 8 and REF.9 ESPM procedures.

- Make sure that the installation is in accordance with REF 3 Airbus SB "AFTER" configuration (Figures on pages 14 and 15) and REF 5 IPC figure.

**END.REV** (3) Test If hydraulic ho ses, Green EMP electrical plug(s) and / or electrical feeder cables have been disconnected for repair or replacement, do an operational test of the Green EMPs as per AMM 29 - 21 - 00 Page Block 501. (4) Close - up

- Make sure that the work areas are clean and cl ear of tools and other items.

- Remove the access platform.

- Close the main landing gear (MLG) door LH (AMM 32 - 12 - 11 Page Block 301). 4.3 MATERIAL AND TOOLING For details about the material for both installation configurations, you can refer to

- REF.3 Airb us SB (Page 7) for components.

- REF.4 IPC 29 - 21 - 03 figure 1 for pre - Airbus SB and pre - Airbus Modification configuration.

- REF.5 IPC 29 - 21 - 03 figure 1C for post - Airbus SB or post - Airbus Modification configuration.

- REF.6 IPC 24 - 92 - 03 Figure 17 for electrica l conduits, feeder cables installation.
5.FURTHER ACTION An improvement of the clamping of the electrical conduits and hydraulic pressure hoses is being reviewed. The solution is expected to be available (Airbus Service Bulletin) by second half of 2012. For your information, as the reported chafing phenomenon is a long term process, with the current AOT ́s inspection requirement enough time will remain for implementation of the forthcoming solution, Airbus Service Bulletin.
6.AOT APPROVAL The technical content of this AOT has been approved under EASA DesignOrganization Approval EASA.21J.031.

**BEG.REV** 7.ACKNOWLEDGEMENT / REPORTING 7.1 ACKNOWLEDGMENT Operators are requested to acknowledge receipt of this AOT within 48 hours after receipt to: Mlle L aetitia BONNET, SEEL Phone number: +33 (0)5 67 19 24 40 Fax number: +33 (0)5 61 93 32 73 E - mail: Laetitia.bonnet@airbus.com This acknowledgement can be made through the Airbus field service office where available. 7.2 QUESTIONS / REPORTING Questions re garding this AOT and inspection results, with or without findings, are to be sent (See in below note the requested information) to Airbus Customer Services Engineering as soon as possible after the AOT application, to the attention of: Mr. Georges GENIN SE EL4 Phone number: +33 (0)5 61 93 49 29 Fax number: +33 (0)5 61 93 32 73 E - mail: georges.genin@airbus.com Note:

- Aircraft MSN.

- Any previous issues on parts / installation to be inspected by this AOT.

- Implementation date of mandatory REF 3 Airbus SB.

- If any, detailed description of the findings with, if possible, pictures of the affected parts / installation.

- If any, detailed which parts have been repaired or replaced, **END.REV** Best regards, E. VAN AELST VICE PRESIDENT A300 PROGRAMME CUSTOMER SE RVICES DIRECTORATE