Learn how to use autopilot in a flight simulator: engage AP correctly, choose HDG, NAV, ALT, VS or FLC, and fix common route and mode errors.
To use autopilot in a flight simulator, first stabilise and trim the aircraft, set the desired heading, altitude and speed, select a lateral mode such as HDG and a vertical mode such as ALT or VS, then engage AP. Confirm the active modes on the flight-mode annunciator and keep monitoring the aircraft.
This basic method applies across general flight simulators, including Microsoft Flight Simulator, X-Plane, Prepar3D and FSX. The exact buttons and mode logic depend more on the aircraft and its avionics than on the simulator itself.
What does autopilot actually control?
Autopilot controls the aircraft's flight path through lateral and vertical modes; it does not automatically make every decision or manage the engine power.
| Mode | What it does | What the pilot must watch |
|---|---|---|
| HDG | Turns towards and maintains the heading bug | Heading selection and turn direction |
| NAV | Follows guidance from the selected GPS, FMS, VOR or localiser source | Navigation source, active route leg and capture status |
| ALT | Holds the altitude captured when the mode becomes active | Selected altitude and altimeter setting |
| VS | Maintains a selected vertical speed | Airspeed, power and the altitude capture |
| FLC or IAS | Uses pitch to maintain a selected airspeed while climbing or descending | Engine power and selected altitude |
| VNAV | Follows a calculated vertical profile where supported | Correctly programmed route, restrictions and mode status |
| APR | Captures compatible lateral and vertical approach guidance | Approach setup, interception and minimums |
The flight director displays the commands as guidance bars; it does not move the controls by itself. Engaging AP allows the autopilot servos to follow those commands. Our explanation of autopilot axes, targets and flight modes covers that relationship in more detail.
How do you engage autopilot correctly?
The safest way to engage autopilot is to establish a controlled flight condition first, configure its targets and modes, and then verify what the system actually captured.
- Hand-fly to a stable condition. Establish a safe altitude, sensible airspeed and modest pitch and bank angle. Trim the aircraft so it is not demanding a large control correction.
- Set the targets. Move the heading bug to the required heading, select the intended altitude and set any applicable airspeed or vertical-speed target.
- Choose the navigation source. For route following, confirm that the CDI or navigation source is using the correct GPS, FMS or radio receiver. Selecting NAV with the wrong source is one of the mistakes we see most often.
- Switch on the flight director. Select a lateral mode such as HDG and a vertical mode such as ALT, VS or FLC. HDG and ALT are the simplest combination for a first attempt.
- Engage the AP master. Release unnecessary pressure on the controls and press AP. Do not continue steering against the servos.
- Read the flight-mode annunciator. Check the mode indications at the top of the primary flight display or on the autopilot panel. Distinguish modes that are active from those merely armed for later capture.
- Monitor the result. Watch heading, altitude, speed, engine power and trim. If the aircraft does something unexpected, disconnect AP, stabilise manually and diagnose the setup before trying again.
Simply selecting a higher altitude usually does not make the aircraft climb. You must also command a climb with VS, FLC, IAS or VNAV. Pressing ALT on many systems captures the present altitude rather than flying towards the altitude shown in the selector.
Why won't the autopilot follow my flight plan?
Autopilot usually fails to follow a flight plan because the wrong navigation source is selected, NAV is only armed, or the GPS/FMS does not have a valid active leg.
- Confirm the route is loaded and has an active leg rather than a discontinuity.
- Select the GPS or FMS source instead of VOR or localiser guidance when following a programmed route.
- Use HDG mode to intercept the desired track if the aircraft is too far away or approaching it at an unsuitable angle.
- Press NAV and check that it changes from armed to active as the aircraft captures the course.
- Do not assume the magenta route line means the autopilot is following it; the annunciator is the authoritative indication.
In Microsoft Flight Simulator, the route, avionics and guidance source must agree. Our walkthrough of connecting the built-in flight planner to GPS and NAV guidance explains that setup.
Why is NAV armed but not active?
NAV remains armed when the aircraft has not yet met the mode's capture conditions. Fly a reasonable intercept in HDG mode, confirm the correct source and allow the course deviation to move towards the centre; NAV should then capture if the route or radio guidance is valid.
Why won't autopilot engage or stay engaged?
Autopilot may refuse to engage when the aircraft is unstable, the system lacks electrical power, a disconnect command is active or a hardware input immediately overrides it.
- Centre the controls and reduce excessive pitch or bank before engaging.
- Check that the avionics, flight director and relevant electrical systems are powered.
- Clear any simulated system failures and release the autopilot-disconnect control.
- Look for duplicate controller assignments, a noisy trim wheel or a button that continually sends an AP-disconnect command.
- Avoid moving manual trim after engagement unless the aircraft's procedure calls for it; manual trim input disconnects many autopilots.
- Check aircraft-specific restrictions, including minimum engagement heights and unavailable modes.
For Microsoft Flight Simulator, use our step-by-step checks for an autopilot that refuses to engage.
Does autopilot control speed and land the aircraft?
Autopilot does not necessarily control thrust, and approach mode does not automatically mean the aircraft can land itself.
VS mode controls climb or descent rate, so airspeed can fall dangerously if the selected climb rate is too high for the available power. FLC or IAS mode controls speed with pitch, but you normally still set the thrust unless the aircraft has an armed autothrottle or autothrust system. The MSFS 2024 procedure for coordinating altitude, pitch modes and thrust shows this distinction in practice.
APR mode can capture a localiser and glideslope, or compatible GPS approach guidance. An automatic landing requires suitable aircraft equipment, correctly configured systems, supported guidance and the proper aircraft-specific procedure. Many light aircraft must be disconnected and landed manually.
When should you disconnect autopilot?
Disconnect autopilot whenever the aircraft becomes unstable, the active mode is unclear, the automation follows the wrong path or manual flight is required for the approach and landing.
Use the dedicated AP-disconnect control rather than fighting the servos with the yoke or stick. After disconnecting, take positive control, correct pitch and power, retrim if necessary and acknowledge any warning using the procedure modelled for that aircraft.