VACS voice integration

FlightStrips can integrate with VACS (VATSIM ATC Communication System) so you can place and receive voice calls between controllers without leaving the strip board. The integration is frontend-only: FlightStrips talks to VACS over a WebSocket on port 9600; no voice traffic passes through the FlightStrips backend.

Prerequisites

Before enabling the integration, make sure VACS is available where FlightStrips can reach it:

1. VACS is running with remote control enabled, reachable at ws://localhost:9600/ws on this machine, or at ws://<host>:9600/ws on another PC on your network (see remote VACS host below).
2. Remote control is enabled in VACS settings. Without it, FlightStrips cannot connect and the phone button stays disabled.
3. You are signed in to VATSIM in VACS so signaling and WebRTC can authenticate.
4. VACS is connected to a signaling position (your controller position is known to VACS). If VACS reports an ambiguous position, resolve it in VACS before dialing.

FlightStrips does not install or bundle VACS; you run VACS separately, same as EuroScope or your browser.

Enable the integration

The feature is off by default. To turn it on:

1. Open the settings control in the command bar (gear icon next to the clock).
2. Check Enable VACS voice integration.
3. Optionally enter a VACS machine address (IP or hostname) if VACS runs on another computer; leave the field empty to use this machine (localhost).

Preferences are stored in your browser:

Setting	localStorage key
Integration on/off	flightstrips.vacs.enabled
Remote host (optional)	flightstrips.vacs.host

Reloading the page keeps your choices; other browsers or profiles start with the feature disabled and no custom host.

When enabled, a phone button appears in the command bar between the settings gear and the clock.

Remote VACS host

Use the address field when FlightStrips runs in a browser on one PC but VACS runs on another (for example EuroScope and VACS on a gaming PC, FlightStrips on a tablet). Enter only the IP or hostname — not a full ws:// URL. The port is always 9600.

• Empty field → ws://localhost:9600/ws
• 192.168.1.10 → ws://192.168.1.10:9600/ws

Remote control must be enabled on that VACS instance, and your network must allow TCP to port 9600. Changing the address reconnects immediately when the integration is enabled.

Phone button states

Hover the button for a short explanation of the current state.

Appearance	Meaning
Grayed out	VACS unavailable, not authenticated, disconnected from signaling, or position ambiguous
Normal (bay color)	Idle — ready to dial
Orange, pulsing	Incoming call or outgoing call ringing
Green	Connected — on an active call
Brief red flash	Call is ending

If more than one call is waiting, a small badge on the button shows the count (incoming only).

Placing a call

1. While idle, click the phone button.
2. The dial dialog lists other controllers on the FlightStrips board:
   • Available — matched to a VACS client; use Dial.
   • Not on VACS — on the board but no matching VACS client (shown dimmed).
3. With more than ten other controllers, a search box filters by callsign or position.

While the callee’s phone is ringing, your button uses the same orange pulsing style as an incoming call. Click or right-click the button to cancel the outgoing attempt.

Matching uses position and callsign from FlightStrips against VACS positionId and displayName. FlightStrips does not send VATSIM CIDs for controller matching; both systems must agree on position/callsign naming for a peer to appear as dialable.

Receiving a call

When a call arrives:

• The button turns orange and pulses.
• Click to accept (oldest waiting call if several are queued).
• Right-click to reject.

During and after a call

• Connected: the button is green. Click to end the call (brief red flash while hang-up is processed).
• Right-click while connected also ends the call.

Audio is handled entirely by VACS and WebRTC; FlightStrips only drives signaling (start, accept, reject, end) via the VACS remote-control API.

Troubleshooting

Phone button is grayed out

Tooltip message	What to do
VACS not running, or remote control not enabled	Start VACS; enable remote control in VACS settings
Sign in to VATSIM in VACS	Complete VATSIM login inside VACS
VACS is not connected to a signaling position	Connect VACS to your position; check network and VATSIM session
Your VACS position is ambiguous	Resolve position selection in VACS

Controller appears under “Not on VACS”

They are on the FlightStrips board but FlightStrips could not match them to a VACS ClientInfo entry. Typical causes:

• They are not running VACS or are not on the same VACS session.
• Their VACS positionId / displayName does not match their FlightStrips callsign or position string.

Dial fails with an error toast

Check the browser console for VACS invoke errors. Common issues include invalid call targets or missing CallSource data when your own VACS client is not yet in the session snapshot. Retry after VACS shows you as connected.

Integration enabled but no phone button

Confirm the checkbox in settings is on and refresh the page. The button is not rendered when the integration is disabled.

For developers

Implementation lives under frontend/src/vacs/ (VacsClient, subscriptions, matching) and frontend/src/components/commandbar/ (VACSBTN, VacsDialModal). Tests: frontend/src/vacs/vacs-client.test.ts, VACSBTN.test.tsx.

• WebSocket URL: buildVacsWsUrl() in frontend/src/lib/vacs-settings.ts (localhost when host is empty; port 9600 fixed).
• VacsClient.updateUrl() reconnects when the host setting changes.
• Signaling uses VACS invoke commands such as signaling_start_call, signaling_accept_call, and signaling_end_call.
• Call targets use lowercase enum tags (client, position, station); source is a CallSource object (clientId, positionId, stationId), not a plain position string.

To work on the UI locally, run VACS with remote control on port 9600 and enable the integration in FlightStrips settings.