Airbus captain experienced radio interference from VHF 3 when data was transmitted during approach a...

Narrative:

Data VHF radio 3 transmits bursts of data at low altitude on approach which is aurally picked up in VHF1. This blocks radio reception; such as from tower; at a very busy and critical time. This model of radios; in earlier serial numbers; has a service bulletin (sb); but when this issue was reported years ago; there was no pertinent sb; so it was dropped by maintenance. It remains; however; an ongoing issue. It is not a given that it will happen; and it seems more common in denver than other stations; and it seems to apply to all aircraft; old and new; A318 through A321; whether it is a problem with the filter in VHF1 or an antenna problem or bnc connector problem or an overly strong transmission by VHF3; there is something wrong with the radio setup. Honeywell knows that this is a problem but took no action years ago. Maintenance control discouraged a request to pilots to write-up radios which do it; probably because they knew how it would disrupt operations; but I think this should be done to at least document the events.

Original NASA ASRS Text

Title: Airbus Captain experienced radio interference from VHF 3 when data was transmitted during approach and the transmission bled through to VHF 1; making ATC communication difficult.

Narrative: Data VHF radio 3 transmits bursts of data at low altitude on approach which is aurally picked up in VHF1. This blocks radio reception; such as from tower; at a very busy and critical time. This model of radios; in earlier serial numbers; has a Service Bulletin (SB); but when this issue was reported years ago; there was no pertinent SB; so it was dropped by Maintenance. It remains; however; an ongoing issue. It is not a given that it will happen; and it seems more common in Denver than other stations; and it seems to apply to all aircraft; old and new; A318 through A321; whether it is a problem with the filter in VHF1 or an antenna problem or BNC connector problem or an overly strong transmission by VHF3; there is something wrong with the radio setup. Honeywell knows that this is a problem but took no action years ago. Maintenance control discouraged a request to pilots to write-up radios which do it; probably because they knew how it would disrupt operations; but I think this should be done to at least document the events.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1416978
Time
Date	201701
Local Time Of Day	0601-1200
Place
Locale Reference	DEN.Airport
State Reference	CO
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Airbus 318/319/320/321 Undifferentiated
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Flight Plan	IFR
Component
Aircraft Component	VHF
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe

Airbus captain experienced radio interference from VHF 3 when data was transmitted during approach and the transmission bled through to VHF 1; making ATC communication difficult.