Subject: ATA 29 - Hydraulic Power - Inspection of electrical feeder 

cables

and green hydraulic system electrical motor pump pressure hose

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 Parker (Formerly Abex) configuration.

OUR REF: AOT A310-29A2102 dated 12 April 2011

1. AIRCRAFT AFFECTED

All A310-200/-300 aircraft equipped with Parker (formerly Abex) 

Hydraulic

Electrical Motor Pump (EMP) models.

2. REFERENCED DOCUMENTATION

REF.1: AOT A310-29A2101 Rev 01 dated 12 April 2011 for one time visual

inspection of the Eaton (formerly Vickers) installation condition.

REF.2: IPC 29-21-03 Figure 1A (Green Parker EMP installation).

REF.3: IPC 29-21-03 Figure 1D (Green Parker EMP installation.

REF.4: IPC 24-92-03 Figure 17 (Green Parker EMP electric feeder cable

installation at Frame 54 zone 147).

REF.5: AMM 20-23-11 Paragraph 7.Permitted damage and defects on 

flexible

hydraulic hoses.

REF.6: ESPM 20-53-21 Repair of standard cables (Damage check and repair

procedures).

REF.7: ESPM 20-53-31 Repair of convoluted conduits (Damage check and 

repair

procedures).

REF.8: AMM 29-21-11 Removal / installation of the Green EMP

REF.9: AMM 20-23-14 Paragraph 2.B. (4) Installation of spiralex band

(Spiral strip) NSA849000.

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

selected 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 electrical 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. Following this event the REF.1 AOT was

issued for a one time inspection of the Eaton (formerly Vickers)

installation condition.

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

Similarly to REF.1 AOT Rev 01, this AOT is to request, for aircraft

equipped with Parker (formerly Abex) Green EMPs,

- 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.2 or REF.3 IPC figures),

. The electrical conduits, feeder cables (REF.4 IPC figure),

. The associated clamping device at Frame 54 as well as the electrical

conduits, feeder cables (REF.4 IPC figure) underneath the clamps. This

requires removal of the concerned clamps.

This AOT is applicable to all A310-200 / -300 with Parker (Formerly 

Abex)

EMP models fitted.

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 for 

installation

in the cockpit of a locally manufactured placard forbidding the inflight

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 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 panel 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 above placard, that 

the

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 completed (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 electrically 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.

-Depressurize the Green hydraulic system (AMM 29-10-00 Page Block 301).

(2) Inspection / replacement procedure

Perform the following inspection with repair and/or replacement if

required:

-Inspect the clamps, the electrical conduits, the feeder cables and

hydraulic pressure hoses for correct condition and installation (See 

REF.2

or REF.3 IPC figures),

 * Thoroughly check if there is chafing at the upper hydraulic hose, 

FIN

 291576, where it crosses the electrical conduits,

 * Remove clamps securing the electrical conduits (See REF.4 IPC

 figure), 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 (Hydraulic pressure hoses, Electrical 

conduits,

feeder cables, clamps).

 * For permissible damage and defects on hydraulic hose, see REF.5 AMM

 procedure.

 * For repair of electrical conduit and feeder cable, see REF.6 and

 REF.7 ESPM procedures.

-Make sure that the installation is in accordance with REF.2 or REF.3 

IPC

figures (See below note).

Note:

For REF.3 IPC figure, please discard the "view B" as there is no

clamps and spacer installed. The REF.3 IPC figure will be updated by

removing the "view B" and reflect similar installation as per REF.2

IPC figure.

-By orienting the two elbows of the upper hydraulic hose FIN 291576,

optimize its clearance with the electrical conduits (See REF.8 AMM

procedure).

 * If the clearance obtained is less than 1 inch (25.4 millimetres)

 install a spiralex band (Spiral strip) NSA849000T125, as per REF.9

 AMM procedure, on the length of the upper hydraulic hose FIN 

291576.

 * Record the lowest clearance between the hose FIN 291576 and

 electrical conduits (LH or RH) or structure, before and after 

repair

 or if necessary after re-orientation of the hose ́s elbows. Indicate

 between which parts (LH or RH electrical conduits or structure) the

 lowest clearance has been recorded.

(3) Test

If hydraulic hoses, 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 clear 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.2: IPC 29-21-03 Figure 1A (Green Parker EMP installation).

REF.3: IPC 29-21-03 Figure 1D (Green Parker EMP installation).

REF.4: IPC 24-92-03 Figure 17 for electrical 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 Design

Organization Approval EASA.21J.031.

7. ACKNOWLEDGEMENT / REPORTING

7.1 ACKNOWLEDGEMENT

Operators are requested to acknowledge receipt of this AOT within 48 

hours

after receipt to:

Mlle Laetitia 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 regarding 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 SEEL4

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.

-If any, detailed description of the findings with, if possible, 

pictures

of the affected parts / installation and of the global installation 

view.

-If any, detailed which parts have been repaired or replaced,

-At the upper hydraulic hose FIN 291576 where it crosses the electrical

conduits, record the lowest clearance before and after repair or, if

necessary, after re-orientation of the hose ́s elbows

 * Indicate between which parts (LH or RH electrical conduits or

 structure) the lowest clearance has been recorded.
Best regards,

E. VAN AELST

VICE PRESIDENT A300 PROGRAMME

CUSTOMER SERVICES DIRECTORATE