The AI ATC Radio

Simmers' ATC is a live, spoken radio simulation you can talk to during a flight, not a scripted checklist of buttons. It follows your flight phase, understands what you say over the frequency, and replies in character with realistic phraseology, the same way a real controller would work you from clearance delivery to shutdown.

How a call actually works

Open a hands-free call or use push-to-talk from the Cockpit, then speak like you would on a real frequency: state your callsign, say what you want, and wait for a reply. ATC listens for your intent, not exact wording, so "request IFR clearance to Vienna" and "requesting clearance, destination LOWW" both work.

A typical exchange during clearance delivery looks like this:

• You: "Belgrade Delivery, JU337, request IFR clearance to Vienna, information Bravo."
• ATC: "JU337, cleared to LOWW, expect flight level 340 after departure, squawk 4521, advise ready for startup."
• You: "Cleared to LOWW, expect flight level 340, squawk 4521, JU337."
• ATC: "JU337, readback correct. Contact ground, 121.9. Good day."

Readback verification

Some instructions require you to read them back before ATC moves on, the same as real-world radio discipline: IFR clearance, pushback, startup, taxi, takeoff, landing, and taxi-in. ATC checks that the key part of the instruction, and the runway if one was given, actually came back in your response. It's a lightweight check, not full understanding of every word, so read back the numbers and the key phrase and you're good. Get it wrong or skip it and ATC will ask you to say it again rather than silently accepting it.

Realistic phraseology

Callsigns and numbers come through the way they do on a real frequency. Airline callsigns use the carrier's voice callsign where Simmers knows it (for example JU337 is spoken as "Air Serbia three three seven"), and digits follow aviation pronunciation: "tree" for 3, "fower" for 4, "fife" for 5, "niner" for 9. Runways, squawk codes, and altitudes are spoken the way ATC actually says them, not as plain numbers.

Frequencies and controllers

ATC follows you through the normal handoff chain as your flight phase changes, delivery, ground, tower, departure, center, approach, matching whichever station would actually be working you at that point. You don't need to manually change frequency, the correct controller answers based on your current phase.

Talking to ATC

A few things you can say, grouped by what they do:

Clearance and pushback

• "Request IFR clearance to [destination]"
• "Request pushback and startup"
• "Request taxi to runway [runway]"

Departure and en route

• "Ready for takeoff" / "request takeoff clearance"
• "Request climb to [altitude]"
• "Request frequency change"

Arrival and landing

• "Request descent"
• "Request approach clearance"
• "Request landing clearance"
• "Runway vacated" / "request taxi to gate"

General

• "Say again" / "come again" if you missed the reply
• Plain readbacks of whatever ATC just cleared you for

If it mishears you

Speech-to-text isn't perfect, especially with sim audio and background noise. Simmers filters out known transcription noise, boilerplate phrases that sometimes get picked up from silence or background hum, before treating anything as something you actually said, so a stretch of silence shouldn't get read back to you as a bogus transmission. If ATC still misunderstands you, just say it again.

How the voice technology works

Speech recognition and speech generation both run on Simmers' own self-hosted infrastructure, not a per-message paid API call. That's what the basic voices you hear today are: free, included with your account, and always will be.

We're also testing more advanced, expressive voices for ATC and the First Officer with a small group of pilots. Those cost real money to generate per use, so once they're ready for everyone they'll be offered as a paid option on top of the free basic voices, never instead of them.

Turning it off

Some flights don't need ATC or a First Officer at all. You can turn either one off independently from the Cockpit if you'd rather fly quietly.