Amblikai,
I had this exact thought not too long ago during my training and actually wanted to ask the opinions of those who have to deal with us. We were on the downwind as you mentioned and the radio was packed! This was very early training for me, so I didn't really take in the instructors response, hence going straight to the tower in the hope it would sink it straight away! This was what they emailed me;
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"Thank you for your email. Generally I would expect the pilot to make as many attempts as possible to get an acknowledgement of their Downwind call. In a busy environment it’s hard to pinpoint the reason as to why you didn’t get a response (perhaps you where part of a multi transmission and where not heard).
In any scenario the key is always to maintain a good look out and keep good radio awareness (to help you identify your position in the circuit), fly the circuit as you would normally and if your downwind call is still not acknowledged, make the base leg turn as normal (following whoever is ahead) and try again to let ATC know your position. ATC will be aware of you and would rather you maintain the circuit pattern than extend as this could cause other issues (conflict with instrument approach or transiting traffic outside the ATZ not talking to *******).
Please remember that every scenario is different and it’s hard to give an exact outline on how to act, the above is merely a basic outline on what ATC would expect. Lastly PLEASE NEVER orbit in the circuit without express permission from ATC, there will likely be aircraft behind you and this will cause a dangerous conflict.
The views expressed in this email are those of 2 members of the ATC team at *******. Where we all act on the same laws and procedures however opinion can change throughout.
I hope this answers your question and maybe on a future visit you can pop up the tower for a chat. We are all very friendly.
Happy flying"
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Taught me from the start and have never had to think about it during the crowded circuit anymore
