Every call, on the record

When the alarm goes off, everyone talks on the same channel, short and fast. The OSC, the On Scene Coordinator, has to lead the operation and keep track of what has been said at the same time, and if you miss a few seconds there is nowhere to go back to. Ardenity wanted a shared record with the entire radio traffic written down while the operation is running.

Ardenity arrived with a clear picture of what they wanted to build and how. What none of us knew was how radio traffic behaves when you try to transcribe it. Noise, clipped phrases, call signs and nautical terms that no general-purpose speech engine knows. That showed in the very first test, and it shaped the rest of the project.

OSCA is an Android app the OSC keeps on a tablet next to the radio. It records the traffic in short segments that Whisper transcribes on Ardenity's own machines. A language model then reads the whole conversation. It recognises speakers by call sign, fixes mishearings and compiles the situation in the Mission Hub. That is where the units involved, casualties and decisions sit in table form, so whoever has no time for the log reads the table instead.

We tested against recordings from exercises, found where it broke and rebuilt. What we have now is not what we sketched at the start, and it does its job. Everything that was said is still there, time-stamped line by line. Miss a call and you read up instead of asking for a repeat, and when a new coordinator takes over, the whole picture is in the log.