Learn what heading, course and bearing mean in FSX, how to set HDG and CRS, and why wind, VOR, GPS and autopilot readings often differ.
In FSX, heading is the direction the aircraft’s nose points, course is the intended path or selected radio-navigation line, and bearing is the direction to or from a point. Set a selected heading with the heading bug, set course with the OBS/CRS selector, and read bearing from the ADF, RMI or GPS.
These terms and the default-panel behaviour are the same in boxed FSX and FSX: Steam Edition. Individual add-on aircraft may use different knobs or avionics, but the underlying navigation principles do not change.
Heading, course, bearing and track compared
The simplest distinction is that heading concerns the aircraft’s nose, while course and track concern a path across the ground.
| Term | What it means | Where it is set or read |
|---|---|---|
| Heading | The direction the nose points, normally measured clockwise from magnetic north | Read on the heading indicator or HSI; select a target with the HDG bug |
| Course | The intended ground path, or the VOR/ILS course selected on the navigation instrument | Set with the OBS or CRS control, or defined by an active GPS route leg |
| Bearing | The direction from one position to another, such as from the aircraft to a station | Read from an ADF, RMI, GPS or other navigation display; normally not set |
| Track | The aircraft’s actual path over the ground | Read from a GPS or moving map |
Course has two closely related uses. A pilot may describe a planned course between two points, while an instrument’s course selector chooses the VOR radial or localiser front course to display. Wind can make heading and track different: to maintain an easterly course in a crosswind, the nose may need to point slightly north or south of east.
FSX cockpit instruments normally show magnetic directions. North is 360° or 000°, east is 090°, south is 180° and west is 270°.
How do I set a heading in FSX?
Set a target heading by moving the heading bug, then engage HDG mode if you want the autopilot to turn towards and hold it.
- Find the heading bug. It appears as a small marker on the heading indicator or HSI and may also be shown in an autopilot heading window.
- Turn the HDG knob. Use the panel’s mouse controls to move the bug to the desired magnetic heading. Mouse-wheel support and click areas vary between aircraft.
- Steer manually or select HDG mode. When flying by hand, use the bug as a visual reference. With the autopilot engaged, select HDG hold to command the chosen heading.
- Check the active lateral mode. NAV or APPR mode may replace heading hold, depending on the autopilot. Look at the mode indication rather than assuming the aircraft is following the bug.
The bug does not change the aircraft’s actual heading by itself. A mistake we see constantly is setting the correct number but forgetting to engage the autopilot and HDG mode. Conversely, moving the bug while NAV mode is tracking a route may have no effect.
If gyro drift is enabled, an unslaved heading indicator can slowly disagree with the magnetic compass. Synchronise it periodically using the instrument adjustment or FSX heading-indicator reset control. Do this in straight, steady flight because a magnetic compass is unreliable during acceleration and turns.
How do I set a course or OBS in FSX?
Set a radio-navigation course with the OBS or CRS knob after choosing and tuning the correct navigation source.
- Choose NAV or GPS. For a VOR or ILS, use the relevant NAV receiver. For an FSX flight plan, select GPS as the navigation source where the panel provides a NAV/GPS switch.
- Tune the station. Enter the VOR or ILS frequency in the correct NAV radio and identify the station before relying on it.
- Rotate the course selector. Set the desired inbound or outbound course on the OBS, CDI or HSI.
- Interpret the indication. Check the CDI needle and, for a VOR, the TO/FROM flag. Turn to intercept the selected line rather than chasing the needle with large corrections.
- Select NAV or APPR when appropriate. The autopilot needs a valid signal and a sensible intercept. APPR mode is used for an ILS because it can capture the localiser and glideslope on suitably equipped aircraft.
What changes between VOR, ILS and GPS?
The course selector’s job depends on the selected navigation source.
- VOR: Radials are always named in the direction from the station. To fly inbound on course
090°, select090°with a TO indication; the aircraft is approaching along the station’s270°radial. Our guide to tuning, intercepting and tracking VOR and NDB stations covers the full procedure. - ILS: Set the published front course so the HSI and heading references make sense. The course knob does not move the physical localiser centreline; the transmitted signal defines it.
- GPS: The active route leg normally supplies the desired track, so turning the OBS/CRS knob may do nothing. Select GPS as the source and use NAV mode to follow the route. If the route itself is the problem, see our instructions for creating and loading routes with the FSX Flight Planner.
- ADF/NDB: An ADF points towards an NDB and does not use a VOR-style course selector. A rotatable compass card may be adjusted for easier reading, but that does not command a course.
Can you set bearing in FSX?
In most FSX aircraft, bearing is an observed value rather than a setting.
On a fixed-card ADF, the needle shows relative bearing clockwise from the nose. If the aircraft heading is 070° and the relative bearing is 040°, the magnetic bearing to the station is approximately 110°. Add the two values and subtract 360° if the result exceeds it.
An RMI normally presents magnetic bearing directly: the needle head points towards the station and its tail shows the reciprocal bearing from it. A GPS bearing or BRG field usually points directly towards the active waypoint. These readings change continuously as the aircraft moves.
Do not simply keep an ADF needle centred in a crosswind unless you intend to home to the station. Homing points the nose at the beacon and produces a curved ground track; tracking uses a wind correction to maintain the required course.
Why do the heading, course and bearing disagree?
They usually disagree because they describe different directions, use different references or come from different navigation sources.
- Crosswind: Heading must be offset from course to maintain the desired track.
- Intercept geometry: While joining a VOR radial or localiser, the aircraft heading should differ from the selected course.
- Relative versus magnetic bearing: An ADF may show an angle from the nose, while an RMI or GPS shows a direction from magnetic north.
- Wrong source: The CDI may be connected to NAV1 while the autopilot is following GPS, or the expected frequency may be in NAV2.
- Gyro drift: An unsynchronised heading indicator can disagree with the magnetic compass and navigation instruments.
- Magnetic variation: True and magnetic directions are not interchangeable. FSX’s magnetic and navaid data also represent its own data era, so modern real-world charts can show different values. The worked magnetic and true course plotting exercises explain the conversion principles, which transfer directly to FSX.
Which control should I use?
Choose the control according to what you want the aircraft to follow.
- To turn towards and hold a compass direction, set the heading bug and use HDG mode.
- To intercept or track a VOR radial, tune the VOR, set the OBS/CRS and use the CDI or NAV mode.
- To fly an ILS, tune the ILS, set the front course and use APPR mode when positioned for capture.
- To follow an FSX flight plan, select GPS as the source and use NAV mode; the active leg determines the course.
- To find the direction of a station or waypoint, read its bearing from the ADF, RMI or GPS rather than trying to set it with the heading or course knob.