Squawk Allocation

[fragrantchips]

Is there a rule on how squawk codes are assigned in HK? Is it based on SID, destination or just randomly chosen? Thanks!

[Oasis]

Never noticed a pattern, but then again, I'm pretty oblivious.

[LapSap]

Quick answer- I’ll find out the exact details for you shortly- we (HK CAD) are allocated certain blocks of codes to try to avoid duplication in the region as far as practicable. Obviously the aircraft within our surveillance area need to all have discrete codes to allow automatic correlation by the radar data processor. If not, we end up with an ambiguity and ‘Dupe’ code indication.
For departing aircraft, our radar system automatically allocates the next available code from the appropriate bin at clearance issue stage.

[LapSap]

Here you go:
HK eAIP ENR 1.6 Para 7 System of SSR Code Assignment
https://www.ais.gov.hk/eaip (https://www.ais.gov.hk/eaip_20230323/2023-03-23-000000/html/index-en-US.html)

[fragrantchips]

Quick answer- I’ll find out the exact details for you shortly- we (HK CAD) are allocated certain blocks of codes to try to avoid duplication in the region as far as practicable. Obviously the aircraft within our surveillance area need to all have discrete codes to allow automatic correlation by the radar data processor. If not, we end up with an ambiguity and ‘Dupe’ code indication.
For departing aircraft, our radar system automatically allocates the next available code from the appropriate bin at clearance issue stage.
Do you happen to know how the bins are allocated to each acft? Is it just random or by SID etc. Thanks!

[fragrantchips]

Do you happen to know how the bins are allocated to each acft? Is it just random or by SID etc. Thanks!