The reporter has raised a concern relating to the poor quality of radio transmissions received from the Control Tower at Canberra.
The reporter states they have been operating out of Canberra for many years and the quality of radio transmissions has always been of poor quality in comparison to other Control Towers around the country.
The reporter queries if the controllers in the Tower are using desk microphones as there is a large amount of background noise (clanking type sound). The controllers sound faint as though they are a distance away from the microphone and at times, 'it sounds as though they are talking in a bucket'.
The reporter further states that the use of headsets rather than desk microphones would enable clearer communication from the Tower controllers with less chance of a potential misunderstanding of instructions and/or directions.
Airservices appreciates the opportunity to respond to the concerns raised in the REPCON.
The reporter states poor quality transmissions over many years, with no specific dates or times identified. We have therefore reviewed historical data to determine if there has been a trend of poor-quality transmissions reported.
Our historical data shows work was conducted in late 2018 to resolve low audio volume levels on the Air-Ground-Air system from Canberra tower. This work led to changes to the system and led to improvement in the audio quality and system performance, confirmed through operational testing. No audio quality-related CIRRIS occurrence reports have been received since this work was conducted.
Following receipt of this REPCON, our Canberra technical staff performed Air-Ground-Air test calls to confirm strength and quality of radio transmissions to and from Canberra Tower. This was conducted on both the Aerodrome Controller (ADC) frequency and Surface Movement Controller (SMC) frequency A and B system. The test calls found they were receiving very good signals (no audio dropouts) and that the audio quality present was excellent (they could understand clearly what was being said).
Canberra technical staff also checked the recordings of all test calls and found the recordings were intelligible with just minor volume differences on transmit between SMC A & B system. Brisbane engineering staff performed a check of a sample of Canberra Tower recordings over multiple days and found no evidence to suggest any audio problems were present at those times.
If the reporter experiences future audio-quality issues, we recommend reporting the specific details to us, including date, time, location and frequency so that a targeted investigation can occur.
We have also provided feedback on this report to our Canberra controllers with a reminder to be vigilant when making transmissions and to keep the mouthpiece close to their mouth.
CASA has reviewed the REPCON and Airservices response and has no safety concerns.