PAINTING OF NAVIGATION AND COMMUNICATION ANTENNAS
Reference: 34.00.00001 Issue date: 28-SEP-2021 Last check date: 14-FEB-2022 Status: Open
A/C type/serie: A300, A300-600, A310, A318, A319, ... ATA: 34-00
Engine manufacturer: Supplier:
major update of the document following suppression of the paint touch up in case of paint erosion on leading edge
Purpose / Reason for revision:
of blade antennas
Engineering Support Status: Open
Note: changes are highlighted in bold blue
SUBJECT: Paint erosion on blade antenna leading edge
Table of content
1. PURPOSE.....................................................................................................................................................1
A/ About paint erosion ...................................................................................................................................1
B/ Purpose of the document ..........................................................................................................................2
C/ New process for eroded antenna...............................................................................................................2
D/ About erosion prevention..........................................................................................................................2
2. GUIDELINES.................................................................................................................................................2
A/ Introduction ...............................................................................................................................................2
B/ Surveillance and Radio Navigation Antennas.............................................................................................3
C. Radio Communication Antennas.................................................................................................................5
D. New inspection tasks for blade antennas (ATC, DME, VHF).......................................................................6
E. Application of Fluorescent Paint .................................................................................................................6
F. Prevention of erosion of blade antennas ....................................................................................................7
1. PURPOSE
A/ About paint erosion
The aggressive environmental conditions an aircraft is likely to encounter during its normal life – sand storms, ash clouds, washing
products, skydrol leaks, air erosion – may lead to a progressive degradation of the paint applied to the various antennas at the
time of their manufacture.
Erosion is the wear process whereby the antenna gradually loses the paint layers. Erosion can be mechanical, due to
the friction of the antenna with air, dust and fine particles that lead to paint wear and, if no correction is applied,
even to the structure wear with detrimental effects. Erosion can also be chemical due to reactions that may attack
the paint.
If it is not solved it may lead to corrosion once all the paint layers are worn and the metallic elements are exposed.
Two degrees of erosion can be defined:
Light erosion: the primer, but not the antenna structure, is visible with the naked eye
Deep erosion: the metallic or plastic structure of the antenna is exposed and visible with the naked eye. This situation may
lead to corrosion and/or structural erosion, so that the damage becomes critical
B/ Purpose of the document
The lack of noticeable effects of ageing antennas on their respective NAV/COM systems, the high MTBUR generally achieved with
the antennas, the recommendations of the antenna suppliers to scrap the antennas exhibiting strong paint peeling (for cost
effectiveness reasons), are the most important factors for not accomplishing any subsequent antenna rework.
However, instead of scrapping serviceable but eroded antennas, many customers have shown interest in reconditioning or
repainting them in-house.
C/ New process for eroded antenna
Recent discussions with the supplier of the blade antennas have led to reject the “repainting” option and state that the
antenna must be replaced when it is found eroded.
A grace period is deemed acceptable depending on the erosion level detected on the antenna. The retroactive
application of these new statements is not mandatory.
However, no allowance is possible for antennas affected by other more critical environmental aggressions, such as
debris and pebble impacts or corrosion, and the antenna must be replaced as soon as possible in those cases as the
structural integrity of the antenna may be affected.
D/ About erosion prevention
This article also gives guidance on how to limit the effects of erosion on the leading-edge of blade type antennas by installing
anti erosion tape, as a prevention means.
2. GUIDELINES
A/ Introduction
Airbus basically considers that painting of the antenna is part of the Supplier’s state-of-the-art manufacturing process: The antenna
suppliers are the most qualified parties to give the customers the relevant materials and instructions to rework eroded antennas.
The certification of a given antenna on Airbus aircraft is achieved when the electrical performances of its initial definitions (i.e. with
paint applied during manufacture) are demonstrated to meet the applicable design requirements, such as ARINC, RTCA
recommendations or Airbus specifications (RF, antistatic, aerodynamic, size).
It shall be emphasized that inappropriate in-house rework of antennas may downgrade their performance, thereby affecting
their certified definition.
B/ Surveillance and Radio Navigation Antennas
34-37: MLS Antennas / COBHAM (U1907) former CHELTON (F6175)
Antennas MSL Landing PN 3602-84-00 and MLS Capture PN 1071-84-00 In-house painting is not allowed.
34-42: RA Antennas
As a general statement, the paint touch up on RA antennas are not allowed except if it is mentioned in the supplier CMM.
THALES (F0057) former THOMSON-CNI (F6170):
− ANT140 series: In-house painting prohibited on strip-line antenna radiating element but allowed on small surrounding
surfaces:
Detailed instructions are reflected in the Dec/96 revision of the CMM 34-42-15
Refer to the vendor SIL ANT 140-34-001
− AHV5 (former TRT) series:
Refer to the vendor SIL ANT 140-34-002
− Contact THALES for additional instructions, if necessary.
COLLINS (4V792): In-house painting not allowed (437X and LRA700 series).
HONEYWELL (97896) former ALLIED SIGNAL (27914): In-house painting not allowed.
34-43: TCAS Antennas
As a general statement, the paint touch up on TCAS antennas are not allowed except is if it mentioned in the supplier
CMM.
COLLINS (4v792) – ACSS (1WYD3) former Honeywell – HONEYWELL (97896) former Allied signal.
34-50: ATC-DME Antennas (and bottom omni TCAS antenna when installed)
Example of paint erosion on ATC / DME antenna
As a general statement, the paint touch up on ATC/DME antennas are not allowed except is if it mentioned in the supplier
CMM.
Thus, the following SRM task (which provides procedure for antenna paint touch up in case of paint erosion) will be
modified in order to take into account this modification: SRM 51-75-12-911-010 - paint renewal
The new SRM revision should be published in 2021.
Meanwhile, we recommend to the operator not to apply this task in case of paint erosion: SRM 51-75-12-911-010 -
paint renewal
COBHAM (U1907) former CHELTON (F6175) - RAYAN (F6987) – DORNE & MARGOLIN (85226) In-house painting
not allowed.
34-53: ADF Antennas
COLLINS (4V792) – THALES (F0057) former SEXTANT (F2924) In-house painting not allowed.
34-55: VOR-MKR Antennas
a) MARKER
COBHAM (U1907) former CHELTON (F6175) - RAYAN (F6987) – DORNE & MARGOLIN (85226) In-house painting not
allowed.
b) VOR
COBHAM (U1907) former CHELTON (F6175) - RAYAN (F6987) – DORNE & MARGOLIN (85226) In-house painting not
allowed.
Note: Corrosion treatment may be applied on the receiving elements (Aluminum foils) of the Dorne & Margolin VOR antennas. Dorne &
Margolin recommends the use of a clear epoxy coating (Hi-Gloss) conforming with the MIL 22750.
34-58: GPS Antennas (All Suppliers) In-house painting not allowed.
C. Radio Communication Antennas
23-11: HF Antenna
If slight corrosion marks are reported on the HF antennas, a corrosion treatment can be applied only on the contaminated surfaces:
Refer to SRM TASK 51-75-12-911-010 - Renewal of external paint coatings of Navigation and Communication Antennas
/ repair of HF antennas for procedure and material.
If heavy corrosion of the HF antenna is reported (resulting in noticeable HF range reduction), the replacement of the antenna is
necessary.
23-12: VHF Antennas
Example of paint erosion on VHF antenna
As a general statement, the paint touch up on VHF antennas are not allowed except is if it mentioned in the supplier
CMM.
Thus, the following SRM task (which provides procedure for antenna paint touch up in case of paint erosion) will be
modified in order to take into account this modification: SRM 51-75-12-911-010 - paint renewal
The new SRM revision should be published in 2021.
Meanwhile, we recommend to the operator not to apply this task in case of paint erosion: SRM 51-75-12-911-010 -
paint renewal
COBHAM (U1907) former CHELTON (F6175) - RAYAN (F6987) – DORNE & MARGOLIN (85226) In-house painting
not allowed.
23-28: SATCOM Antennas (All Suppliers) In-house painting not allowed.
D. New inspection tasks for blade antennas (ATC, DME, VHF)
As per above statements, blade antennas presenting paint erosion must be replaced (as per CMM criteria).
Nevertheless, Airbus has defined a grace period before antenna replacement depending of the severity of the erosion.
The following tasks have been included in order to assess paint erosion damages and provide grace period before antenna
replacement:
A320 AMM (November 2020 release):
AMM task 34-51-11-200-801 - inspection of the DME antenna (A320)
AMM task 34-52-11-750-801-A - inspection of the ATC antenna (A320)
AMM task 23-12-11-200-801-A - inspection of the VHF antenna (A320)
A330/A340 AMM:
TASK 23-12-11-200-801-A Inspection of the VHF Antenna
TASK 34-51-11-200-801-A Inspection of the Distance Measuring Equipment (DME): planned for Jan 2022
TASK 34-52-11-200-801-A Inspection of the Air Traffic Control (ATC) Antenna: planned for Jan 2022
A380:
TASK 23-12-11-200-801-A Inspection of the VHF Data Radio (VDR) Antenna
TASK 34-51-11-200-801-A Inspection of the DME antenna: planned for Dec 2021
A350:
A350-A-23-12-11-00001-282A-A (Sept 2021 release) Inspection of the VHF Data Radio (VDR) Antenna
DME: Inspection of the Distance Measuring Equipment (DME): planned for Jan 2022.
E. Application of Fluorescent Paint
As mentioned above, repaint of antenna are not authorized anymore.
Note:
Alternate ATC/DME and VHF antennas pre-painted in production with red stripes can be proposed as options on Airbus aircraft.
Those antennas are referenced and are already certified on A330/A340 (Mod 43213):
VHF Antenna PN 2403-89-06 (COBHAM)
ATC/DME Antenna PN 2407-89-13 (COBHAM)
Installation of such antennas on any Airbus model is subject to the RFC procedure.
F. Prevention of erosion of blade antennas
Experience in-service has shown that the application of adhesive tape on the leading edge of blade shape antennas can be a simple
and efficient way to prevent erosion.
The concerned antennas are the VHF, and ATC/DME ones (and bottom omni TCAS antenna when installed).
The application of polyurethane adhesive tape on these blade type antennas is authorized provided the antenna area where the
radiating element is located is not covered: refer to SRM content.
Despite the smaller dimensions of the antennas, the procedure to apply the adhesive tape is similar to the one described in SRM
51-75-12 for the leading edge of the Vertical Stabilizer. For the choice of material, please refer to CML 05RQB9.
The anti-erosion tape installation must be done as a prevention means, not as a repair. It means that the tape must be
installed on a new antenna, or at least on an antenna which is in good condition (not eroded).
The associated SRM task for anti-erosion tape installation is the following: SRM 51-75-12-911-011 - anti erosion tape
installation on antennas.
This SRM task will be deactivated and replaced by an optional sub task in the antenna installation AMM task.
Restrictions:
a) In case of application of such a tape on the leading edge of these antennas, please be advised that this could, in theory, be at
the origin of micro electro-static discharges to the antennas. In such a case, the Electro-Static discharges could result in noise.
Therefore, if the flight crew reports “static noise” on VHF after application of the adhesive tape, we recommend the Operator to
remove this tape.
b) This procedure is NOT allowed for all other type of antennas (Radio-Altimeter, TCAS, GPS, SATCOM, ADF, etc)
Survey for the Engineering Support section
Annex
General Information
Potential impact: Maintenance
Key information:
Solution benefit:
First issue date: 27-JAN-1995 Issue date: 28-SEP-2021 Last check date: 14-FEB-2022
Technical parameters
ATA: 34-00
A/C type/serie: A300, A300-600, A310, A318, A319, A320, A321, A330, A340, A350, A380
Engine:
Engine manufacturer:
Fault code/ECAM
warning:
FIN:
Part Number:
Supplier:
Attachments
General:
- ISI_34.00.00001_Summary.docx
Links
Other articles (ISI/TFU):
- 23.00.00024, 23.00.00024, 23.00.00024, 23.00.00024, 23.00.00024, 51.00.00002, 51.00.00002
© Airbus SAS, 2022. All rights reserved. Confidential and proprietary document.The technical information provided in this article is for convenience and information purposes only. It
shall in no case replace the official Airbus technical or Flight Operations data which shall remain the sole basis for aircraft maintenance and operation. These recommendations and
information do not constitute a contractual commitment, warranty or guarantee whatsoever. They shall not supersede the Airbus technical nor operational documentation; should
any deviation appear between this article and the Airbus or airline's official manuals, the operator must ensure to cover it with the appropriate document such as TA, FCD, RDAS.
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