EASA SIB NM-14-21
Honeywell RTA 44D VHF Transceivers — Frequency Interference / Spurious Transmissions
Summary
The FAA Special Airworthiness Information Bulletin SAIB: NM-14-21 addresses frequency interference and spurious transmissions issues associated with Honeywell RTA 44D VHF transceivers installed on Airbus A318, A319, A320, and A321 series airplanes. The bulletin informs operators and maintenance personnel about off-frequency transmissions that can interfere with air traffic control communications but do not currently warrant an airworthiness directive. It highlights the affected Honeywell transceiver part numbers 064-50000-0202 and 064-50000-0505 and provides background on the issue and mitigation recommendations.
What Changed
This bulletin introduces awareness of spurious voice transmissions caused by an anomaly in Honeywell RTA-44D VHF transceivers, particularly when operating on frequencies below 121 MHz in the VHF 1 position. It recommends implementing Honeywell Service Bulletin 064-5000-23-4 to install MOD 22 standard on affected transceivers to mitigate interference. It also advises interim operational procedures such as using VHF 2 for tower communications at certain airports prone to interference.
Why It Matters
This information is critical for aviation professionals to prevent communication interference that can disrupt air traffic control operations, especially at busy airports like JFK and Brussels. Operators and maintenance teams need to be aware of the potential for unnoticed spurious transmissions that could affect flight safety and operational efficiency. Implementing the recommended service bulletin helps maintain reliable radio communications and compliance with FAA guidance.
What To Do
Operators of Airbus A318, A319, A320, and A321 aircraft equipped with Honeywell RTA-44D transceivers should implement Honeywell Service Bulletin 064-5000-23-4 to install the MOD 22 standard on affected radios. Until the modification is installed, flight crews should use the VHF 2 radio for tower communications at airports where interference has been observed, such as JFK and Brussels. There is no mandatory compliance deadline stated, but prompt action is recommended in affected airspace.