What is NAV1, and how do I use it in FSX?

NAV1 is FSX and FSX: Steam Edition’s primary navigation-radio receiver. Tune a VOR, localiser or ILS frequency into NAV1, make it active, select NAV rather than GPS, then follow the CDI or HSI needle. The autopilot can also track that signal in NAV or APR mode.

What does NAV1 do in FSX?

NAV1 receives ground-based VHF navigation signals and feeds them to the aircraft’s main course-deviation indicator, HSI or glass display. Depending on the station and aircraft equipment, it can provide:

• VOR guidance: lateral guidance to, from or along a selected radial.
• Localiser guidance: lateral guidance towards an ILS runway centreline.
• Glideslope guidance: vertical ILS guidance, normally through NAV1.
• DME distance: distance to a compatible station when the aircraft has DME equipment.

NAV1 is a receiver, not a navigation mode by itself. Tuning the frequency does nothing useful until the frequency is active, the instrument source is set correctly and the aircraft is within reception range.

How do I use NAV1 to fly to a VOR?

The basic sequence is frequency, active channel, navigation source, course and interception.

1. Choose the VOR. Find its frequency and plan the course you intend to fly. FSX’s map and Flight Planner contain navigation-aid information; our explanation of planning a VOR-to-VOR route with the built-in Flight Planner covers the route-planning side.
2. Tune NAV1. Enter the VOR frequency in the NAV1 standby window, then press the transfer or swap button to move it into the active window. Some panels tune the active frequency directly.
3. Select the radio source. Set the panel’s NAV/GPS switch to NAV. Glass cockpits and add-on aircraft may label this source VLOC, NAV1 or LOC1.
4. Identify the station. Enable NAV1 audio on the audio panel and check the Morse identifier where practical. A frequency alone is not proof that the intended station is being received.
5. Set the course. Turn the OBS or course selector to the planned magnetic course. For a direct course to the station, rotate it until the CDI centres with a TO indication.
6. Intercept the course. If the CDI needle is left of centre, the selected course lies to the left; intercept it with an appropriate angle. Reduce the intercept as the needle moves towards the centre, then maintain the selected course with a wind correction.

The OBS or CRS knob does not turn the aircraft. It selects the VOR course displayed by the CDI or HSI. The heading bug is separate and only commands a heading when the autopilot’s heading mode is engaged.

As you pass over a VOR, the indication may fluctuate or disappear briefly, then change from TO to FROM. That station-passage behaviour is normal.

What is the difference between NAV1, NAV2 and GPS?

NAV1 is normally the primary radio source for the main navigation display and autopilot, while NAV2 is a secondary receiver and GPS follows a stored flight-plan route.

A mistake we see constantly is tuning NAV1 while leaving the source selector on GPS. The frequency remains in the radio, but the CDI and autopilot continue following the GPS route.

Can the FSX autopilot follow NAV1?

The FSX autopilot can follow NAV1 when the radio source is selected and the aircraft is positioned to intercept the course.

Use heading mode to approach the desired VOR course at a moderate angle, then engage NAV as the CDI starts moving towards the centre. NAV mode provides lateral tracking; it does not control altitude or descend on an ILS glideslope.

If the aircraft follows a magenta GPS route, flies straight ahead or turns towards an unexpected course, check the source selector before changing the frequency again. Our guide to how FSX’s GPS/NAV source selection affects autopilot tracking explains that relationship in detail.

How do I use NAV1 for an ILS approach?

For an ILS, tune the published ILS frequency into active NAV1, select NAV or VLOC, set the runway’s front course and intercept the localiser from the approach side.

Use APR rather than ordinary NAV mode when you want a compatible autopilot to capture both the localiser and glideslope. Approach from below the glideslope; arriving above it is a common reason the aircraft never begins descending. The full FSX ILS tuning and capture sequence covers the procedure without duplicating it here.

Why is NAV1 not working in FSX?

Most NAV1 failures are caused by an inactive frequency, the wrong source or an invalid intercept rather than a simulator fault.

• The frequency is still on standby: use the transfer button and confirm it appears in the active NAV1 window.
• GPS is selected: change the navigation source to NAV, VLOC or NAV1.
• NAV2 was tuned by mistake: confirm both the receiver and displayed instrument source.
• The avionics are unpowered: check the battery, avionics master and relevant electrical systems.
• The station is out of range: VOR reception is limited, especially at low altitude or far from the transmitter.
• The OBS course is reversed: check the selected course and the TO/FROM indication. Flying the reciprocal can produce reverse or confusing CDI movement.
• The autopilot cannot capture: use heading mode to create an intercept rather than engaging NAV while parallel to or far from the selected course.
• The ILS glideslope is missing: verify the active frequency, navigation source, approach direction and altitude. These NAV1 and glideslope capture checks cover the usual ILS-specific faults.

Panel layouts differ between default and add-on aircraft. If there is no obvious NAV/GPS switch, look for a CDI source control on the HSI, primary flight display or radio-management panel; the underlying choice is still NAV1 versus GPS or FMS guidance.