ALERT OPERATORS TRANSMISSION - ALERT OPERATORS TRANSMISSION

SUBJECT: ATA 55 - RUDDER SIDE PANEL INSPECTION ALONG THE Z-PROFILE

OUR REF.: A55L001-12 dated 20 Dec 2012

1. AIRCRAFT AFFECTED

All A330 and A340 aircraft in pre modification 41800 configuration, with a rudder assembly Part Number (PN) 

starting with A55471500.

The inspection has to be performed only if the last inspection as per ref.1 or 2 was done off aircraft or if the rudder has 

been removed since then for any reason.

2. REFERENCED DOCUMENTATION

2.1 APPENDIX

Appendix 1: Inspection flow chart

2.2 REFERENCES

Ref.1: Service Bulletin SB A330-55-3038 dated Nov 07/07

Ref.2: Service Bulletin SB A340-55-4034 dated Nov 07/07

Ref.3: Service Bulletin SB A310-55-2044 dated Dec 03/07

Ref.4: NTM Task 55-40-02-270-801 (Ultrasonic inspection)

Ref.5. NTM Task 51-10-26-220-801 (ELCH inspection)

Ref.6: NTM Task 51-10-19-280-801 (Woodpecker inspection)

Ref.7: NTM Task 51-10-03-280-801 (Tap test inspection)

Ref.8: AMM 27-21-41 PB 401 (Rudder removal/installation) prior to Dec 2012

Ref.9: NTM Figure 55-40-09-991-012-A (Rudder inspection zones) 

3. REASON

3.1 FACTS

Affected rudders are subject to Service Bulletins ref.1 and 2 introducing a specific repetitive ultrasonic (UT) inspection 

along the rudder panel front and bottom edge. This inspection is intended to identify possible areas of disbonding on 

the internal surface of the rudder side panels.

One A310 rudder with rudder assembly Part Number (P/N) starting with A55471500 has been recently identified with 

large inner skin disbond damage.

This rudder was inspected as per Service Bulletin ref.3 at 21028 accumulated Flight Cycles (FC) with nil findings. 986 

Flight Cycles (FC) after this inspection subject rudder was sent to Airbus facilities for a specific repair outside the 

scope of the inspection ref.3. The damage was detected during the incoming inspection. 

An investigation revealed that the most probable cause of the large honeycomb core debonding initiation was a blunt 

impact with no visible damage from outside during rudder handling (removal/installation). 
The rudder involved in this event was part number (PN) A55471500 series, which is sensitive to damage in the area of 

the Z-profile during rudder handling. An impact damage might grow with difference of pressure associated to ground 

air ground cycles.

3.2 CONSEQUENCES

An inner skin disbonding of the detected size degrades the structural integrity of the rudder. Tests performed on 

rudders showed a rapid propagation of damage during artificial pressure cycling.

3.3 AIM

The aim of this AOT is to verify the structural integrity of the rudder by means of one time ultrasonic (UT) inspection.

The inspection must be repeated before next flight after any further re-installation of the rudder onto an aircraft until 

issuance of revised AMM task ref.8. This inspection will prevent undetected damage introduced during rudder ground 

handling.

4. SHORT TERM ACTION

4.1 PLANNING AND MANPOWER

4.1.1 ACCOMPLISHMENT TIMESCALE

The inspections described in paragraph 4.2 must be performed within 3 months from the reception date of this AOT. 

4.1.2 MANPOWER

For A330 aircraft, refer to SB ref.1 paragraph 1.G.

For A340 aircraft, refer to SB ref.2 paragraph 1.G.

4.2 DESCRIPTION

4.2.1 ACCESS

Inspection must be performed with the rudder installed on the aircraft. 

For A330 aircraft, refer to SB ref.1 paragraph 3.A.(1).

For A340 aircraft, refer to SB ref.2 paragraph 3.A.(1).

4.2.2 INSPECTION REQUIREMENTS

Refer to flowchart appendix 1 for an overview of the inspection requirements.

Identify the rudder assembly part number and serial number before you start the inspection. If it is not possible, contact 

Airbus for identification advice. 

If installed rudder assembly part number is not starting with A55471500, no further action is required as per this AOT.

Rudder shells must be inspected in areas defined in:
- Figure 2 of SB ref.1, for A330 aircraft.

- Figure 2 of SB ref.2, for A340 aircraft.

Perform an ultrasonic (UT) inspection in accordance with ref.4 in the inspection area. 

If case of finding, the UT indication shall be verified to differentiate disbond damage from other possible damage. This 

differentiation should be done using both methods:

- ELCH in accordance with ref.5 for detection of external/internal disbond.

- Woodpecker in accordance with ref.6 or Tap test in accordance with ref.7 for detection of external disbond.

Note: In case of UT indication in booster area (see ref.9), report to Airbus to get further instructions before next flight. 

If finding is confirmed as disbond damage, refer to Para. 4.2.3.

If finding is confirmed as other type of damage (e.g. liquid ingress), contact Airbus before next flight with a detailed 

damage report to get further instructions.

The inspection must be repeated before next flight after any further re-installation of the rudder onto an aircraft until 

issuance of revised AMM task ref.8.

4.2.3 FINDINGS

In case of disbond with width equal or less than 50 mm (1.968 in.) and with length equal or less than 150 mm (5.905 

in.), vent the core before next flight.

- For A330 aircraft, refer to SB ref.1 paragraph 3.C.(1). 

- For A340 aircraft, refer to SB ref.2 paragraph 3.C.(1).

Then, contact Airbus within 10 days from the date of the inspection with a detailed damage report to get permanent 

repair instructions. The permanent repair shall be performed within 100FC from inspection date.

In case of disbond with width greater than 50 mm (1.968 in.) or with length greater than 150 mm (5.905 in.), contact 

Airbus before next flight with a detailed damage report to get further instructions.

Detailed damage report has to be sent to the following address:

Repair Engineering (SEER1/SEER2/SEER3)

Customer Services

Fax: +33 (0)5 61 93 28 73

Mailto:

region1.StructureRepairSupport@airbus.com

region2.StructureRepairSupport@airbus.com

region3.StructureRepairSupport@airbus.com

Or for AOG request

AIRTAC (Airbus Technical AOG Center)

Customer Services

Phone: +33 (0)5 61 93 34 00

Fax: +33 (0)5 61 93 35 00

Mailto: airtac@airbus.com

4.3 SPARES AND TOOLING
- Inspection equipment for Ultrasonic inspection as per ref.4.

- Inspection equipment for ELCH as per ref.5.

- Inspection equipment for Woodpecker test as per ref.6.

- Inspection equipment for Tap test as per ref.7.

5. FURTHER INFORMATION

5.1 FOLLOW-UP PLAN

The AMM task ref.8 will be revised to include this UT inspection requirement after each re-installation of the rudder 

onto an aircraft. 

The revised AMM is expected to be issued on the second quarter of 2013. 

5.2 IMPACTED DOCUMENTATION

AMM 27-21-41 PB 401

6. AOT APPROVAL

The technical content of this document is approved under the authority of DOA nr. EASA.21J.031.

7. REPORTING / ACKNOWLEDGEMENT

Operators are requested to acknowledge receipt of this AOT within 48 hours after receipt to:

Cecile BORDES SEES 

E-mail: Cecile.bordes@airbus.com

Fax number: +33 (0) 5.61.93.36.14

This acknowledgement can be made through the airbus field service office when available.

Questions about this AOT and inspection results with or without findings are to be sent to Airbus Customer Services 

engineering as soon as possible, after the AOT application, to the attention of:

Paloma LLEDIN BARBANCHO - SEES1

Customer Services

Phone: +33 (0)5 67 19 10 84

Fax: +33 (0)5 61 93 36 14

Mailto: paloma.lledin@airbus.com

Best Regards,

Jean-Luc MOUYSSET Philippe GOURDON

VICE PRESIDENT ENGINEERING SUPPORT VICE PRESIDENT A330/A340 PROGRAMME

CUSTOMER SERVICES CUSTOMER SERVICES