How do COM and NAV radios work in a flight simulator?

In a flight simulator, COM radios send and receive voice communications, while NAV radios receive VOR, localiser and ILS glideslope signals. Power the avionics, place the required frequency in the active window, select the correct transmitter or navigation source, identify the station, then use the audio panel, CDI, HSI or autopilot as appropriate.

This is a simulator-general workflow. The labels and controls vary between analogue radio stacks, glass cockpits, airliners and add-on aircraft, but the underlying COM and NAV functions remain separate.

What is the difference between COM and NAV radios?

COM carries communications; NAV supplies guidance from ground-based navigation aids.

COM1 is normally used as the primary ATC radio, while COM2 can monitor an ATIS, another controller or a second channel. Both receivers may be audible, but only the radio selected as the microphone or transmitter source sends your call unless specialised split operation is modelled.

NAV1 commonly drives the main CDI or HSI and may be the receiver used by the autopilot. NAV2 is useful for a second VOR radial, cross-checking position or displaying another bearing. That wiring is aircraft-specific: many light trainers connect the autopilot only to NAV1, while glass cockpits can assign either receiver to different indicators or bearing pointers.

If the number of buttons and abbreviations is unfamiliar, our guide to audio-panel and radio-stack controls explains the associated ADF, DME, transponder and source-selector controls.

Active and standby frequencies

The active frequency is the one the receiver is using; standby is a preparation window that does nothing until the frequencies are exchanged.

Use the transfer or swap button to move standby into active. Older equipment may tune the active side directly, and some integrated avionics can load or auto-tune frequencies from an airport or approach page. A dual-watch feature, where fitted, is an exception that can monitor standby without making it fully active.

How do I tune and use COM and NAV radios?

The reliable sequence is power, tune, transfer, route, identify and then use the signal.

1. Find the right frequency. Obtain the ATC channel, VOR or runway-specific ILS frequency from the simulator's ATC interface, map or chart data that match its navigation database. An ILS belongs to a particular runway approach, not merely to an airport.
2. Power the avionics. Check the battery, alternator or generators, avionics master, electrical bus and radio controls. More detailed aircraft may model individual circuit breakers or bus failures.
3. Tune the intended receiver. Enter the frequency in COM1, COM2, NAV1 or NAV2. On a conventional concentric knob, the outer and inner sections usually change different parts of the frequency, although the exact arrangement varies.
4. Transfer it to active. Press the swap button and verify the active display. A correct number left in standby will not operate the radio.
5. Route the radio. For COM, select the required transmitter and enable any receivers you want to hear on the audio panel. For NAV, set the CDI or HSI source to NAV, NAV1, NAV2 or VLOC rather than GPS or FMS.
6. Set the course. For a VOR, use the OBS or course control to select the desired inbound or outbound course. For a localiser, set the published front course for a sensible HSI and autopilot presentation; changing the course knob does not move the localiser beam.
7. Identify the station. Listen for its Morse identifier or confirm the decoded ident if the avionics provide one. Matching the frequency alone is not enough, especially where scenery and navigation databases may disagree.
8. Use the radio. Make a COM transmission through the simulator's ATC interface, push-to-talk system or supported voice client. For NAV, follow the CDI or HSI indication and watch its TO/FROM or signal-valid flags as appropriate.

A common failure is tuning COM2 while the audio panel still transmits on COM1. Its NAV equivalent is tuning NAV1 correctly but leaving the CDI source on GPS. The frequency display looks right in both cases, yet the selected system is using something else.

For a worked example in a familiar light-aircraft cockpit, see our practical Cessna radio-stack procedure. If the frequency is active but the needle presentation is confusing, our explanation of VOR and VLOC indications on an HSI covers source selection, course setting and CDI interpretation.

How do I use the radio in Microsoft Flight Simulator 2024?

Microsoft Flight Simulator 2024 uses the same power-tune-transfer-select sequence on PC, Xbox Series X|S and PlayStation 5 or PS5 Pro, although cockpit interaction and compatible hardware differ by platform.

1. Power the aircraft first. In a cold-and-dark cockpit, turn on the required electrical source and avionics rather than assuming the dark radio display is a fault.
2. Focus the radio control. Use the mouse or the console's cockpit cursor to select the frequency knob, active/standby field or touchscreen control. The interaction prompts depend on the selected cockpit-control preset and aircraft.
3. Enter and swap the frequency. Adjust the whole and fractional portions, then use the transfer control. Confirm that you changed the intended COM or NAV radio.
4. Select the audio or navigation source. Choose COM1 or COM2 as the transmitter for communications. For a VOR or ILS, change the flight instrument from GPS/FMS guidance to NAV or VLOC.
5. Use the matching communications method. Built-in ATC normally uses its interaction panel and menu responses; it does not necessarily require a microphone. External voice operation requires its own supported software, push-to-talk assignment and matching COM selection.

Some ATC interactions and assistance features can tune or manage radios automatically. If a frequency changes immediately after you set it, check whether radio or communications assistance is controlling it before treating the behaviour as an avionics failure.

There is no universal MSFS radio shortcut that behaves identically in every aircraft. Default aircraft often respond to standard COM and NAV bindings, while detailed add-ons may use custom avionics logic, touchscreen pages or controls that must be operated in the cockpit.

Does tuning a NAV radio make the autopilot follow it?

No; tuning a NAV frequency only makes its signal available to the aircraft.

To track a VOR, select the appropriate NAV or VLOC source, set the course, establish a sensible intercept and engage the aircraft's lateral NAV mode. The mode annunciation should confirm what the autopilot is actually following; a lit frequency display proves only that the receiver is tuned.

For an ILS, the tuned localiser frequency normally pairs the glideslope receiver automatically. Select VLOC or NAV, set the front course and intercept the localiser from a suitable angle. Approach mode can then capture the localiser laterally and the glideslope vertically, provided the aircraft approaches from below the glideslope with valid signals.

Do not assume that loading an ILS into the GPS has switched the CDI to the radio receiver. Some avionics perform an annunciated automatic changeover, while others require a manual source change. Our guide to choosing GPS or NAV mode for an ILS explains when VLOC is required.

Why is my COM or NAV radio not working?

Most simulated radio faults are caused by power, selection, range, data or control-binding errors rather than a failed receiver.

VOR and ILS reception is largely line-of-sight. Terrain, low altitude, excessive distance and being outside the directional localiser or glideslope coverage can remove the indication even when every cockpit setting is correct.

When diagnosing a problem, read five items directly from the panel: active frequency, radio number, COM transmitter, CDI source and autopilot mode annunciation. Those checks expose most cases where a correctly tuned radio is connected to the wrong output.

Can I use flight-simulator radio hardware on Xbox?

On Xbox Series X|S, use only radio hardware that explicitly supports Xbox and the intended Microsoft Flight Simulator setup; a generic USB panel designed for PC should be assumed incompatible.

• Check the connection method. Some supported panels connect through a compatible yoke, throttle or control hub rather than directly to the console.
• Check individual functions. Frequency tuning, transfer buttons, illuminated displays, audio-panel selection and transponder controls may not all receive the same level of support.
• Allow for aircraft differences. Hardware may operate default avionics through standard simulator events but fail to control a complex add-on that uses custom radio logic.
• Avoid duplicate inputs. If a panel continually changes a frequency, clear overlapping controller assignments and test one device at a time.

A controller, mouse or supported cockpit cursor remains the dependable fallback. Before buying an Xbox flight-simulator radio panel, verify console support, any required companion hardware and compatibility with the aircraft functions you intend to control.

Flight-sim radios are not RC receiver channel assignments

RC receiver channel assignments have no relationship to COM1, COM2, NAV1 or NAV2.

In radio-controlled models, receiver channels map control signals such as aileron, elevator, throttle, rudder and accessories. Their numbering and order depend on the transmitter system, receiver and user configuration, so this flight-simulator radio procedure must not be used as an RC wiring guide.