How do I assign separate throttle levers in FSX with FSUIPC?

To assign separate throttle levers in FSX or FSX: Steam Edition, remove every duplicate throttle assignment in FSX, then map each physical axis in FSUIPC to Throttle1, Throttle2 and any remaining engines. Send the axes direct to FSUIPC Calibration, calibrate them individually, and use an aircraft profile when the layout is not global.

These instructions apply to boxed FSX and FSX: Steam Edition using FSUIPC4. Axis assignment and joystick calibration require FSUIPC's registered user facilities; an unregistered installation may still support add-ons without enabling those control features. If FSUIPC is absent from the FSX Add-ons menu or the required tabs are unavailable, follow our FSUIPC4 installation and loading checks.

How do I map each throttle lever to a separate FSX engine?

The reliable method is to give FSUIPC sole ownership of the throttle axes while allowing FSX to retain any buttons, yoke or rudder assignments you still want it to handle.

1. Remove the FSX throttle assignments. Open Options > Settings > Controls and select the Control Axes section. Check every connected device in the controller list, then delete the generic throttle axis and any engine-specific throttle axes that FSUIPC will manage. Do not disable all FSX controllers unless FSUIPC or another utility also owns every other flight control.
2. Load a suitable aircraft. Start with the default Beechcraft Baron 58 or another default twin. This gives you a known aircraft for testing before introducing an add-on's custom throttle logic.
3. Open FSUIPC. Select FSUIPC from the FSX Add-ons menu and open the Axis Assignment tab.
4. Choose global or profile-specific control. Enable Profile Specific before making assignments if this quadrant layout is intended for the loaded aircraft or a particular aircraft family. Leave it disabled only when the same lever arrangement should apply to everything you fly.
5. Identify the first physical lever. Select Rescan, then move only the left-hand lever through most of its travel. Confirm that the displayed joystick and axis values respond to that lever rather than a noisy axis on another device.
6. Assign Engine 1. Select Send direct to FSUIPC Calibration and choose Throttle1 in an assignment field. Do not assign the generic combined Throttle control as well.
7. Assign the other engines. Rescan, move the next lever and assign it to Throttle2. Repeat with Throttle3 and Throttle4 when using four physical levers. Engine 1 is the leftmost engine when seated in the cockpit and facing forwards.
8. Calibrate every channel. Open Joystick Calibration and find the separate engine-throttle controls. Activate calibration for each assigned channel and record its aft and forward limits with the appropriate Set controls. Leave a small margin inside each hard stop so normal hardware variation still reaches idle and full power.
9. Select the correct reverse arrangement. If the lever's aft stop is idle, enable the no-reverse-zone option. If the axis has physical travel below an idle detent, define the idle region and reverse endpoint instead. Our detailed throttle calibration procedure covers endpoint, idle and reverse-zone setting without copying unsuitable values from another quadrant.
10. Test one lever at a time. Select OK, ensure any autothrottle is disengaged and move only the first lever. Engine 1 should respond while Engine 2 remains still; repeat for every channel. Check manifold pressure, RPM or N1 as well as the animated cockpit levers.

FSUIPC stores these assignments in its configuration and applies profile-specific settings according to the loaded aircraft. Add-on liveries can use different aircraft titles, so they may need to be added to the same profile. Our guide to FSUIPC control ownership and aircraft profiles explains that broader setup.

Which FSUIPC throttle assignment mode should I use?

Use direct FSUIPC calibration for default FSX aircraft and conventional add-ons, but use normal FS axis controls when an aircraft's documentation explicitly requires standard FSX events.

Do not send the same physical axis through both modes. If separate levers work in the default Baron but not in one add-on, the quadrant and basic FSUIPC mapping are sound; change only that aircraft's profile to the control mode required by its documentation.

Why do both FSX throttle levers still move together?

Both levers usually move together because a combined throttle axis remains assigned in FSX, FSUIPC or the controller's own configuration software.

• Check every FSX controller. A yoke, gamepad or unused joystick may have received an automatic throttle assignment. FSX can also treat a controller as a new device after hardware or USB changes and create default assignments again.
• Inspect the FSUIPC axis fields. The first physical lever should have only its intended engine assignment and the second should have only the next one. Remove any unwanted generic Throttle assignment.
• Turn off autothrottle for the test. An active autothrottle can command both engines regardless of the physical lever positions.
• Test a default twin. If its engines respond independently, linking seen only in one add-on is caused by that aircraft's control logic, throttle synchronisation or required assignment mode.
• Distinguish linking from hardware noise. A lever that flickers while untouched usually indicates an unstable potentiometer or calibration issue; a lever that follows another axis points more strongly to duplicate assignments.

How do I fix a reversed, jumping or incomplete throttle lever?

Reverse the axis in one place only, then recalibrate its endpoints before investigating the hardware.

• Reversed travel: enable Rev for that channel in FSUIPC calibration and set its endpoints again. Do not also reverse it in FSX or the hardware software, because two reversals cancel each other.
• Jumping or snapping: remove duplicate assignments first. If the raw input value still changes while the lever is untouched, inspect it in the Windows game-controller panel for electrical noise.
• Idle or full power cannot be reached: recalibrate that lever with a small margin inside both physical stops. Never copy another lever's numerical values; even two axes on the same quadrant can have different ranges.
• No response in one aircraft: confirm that the intended FSUIPC profile is active and test the same axis in a default aircraft. Use our FSX throttle fault checklist if the raw axis is not detected or stops responding across all aircraft.

Can two throttle levers control four FSX engines?

Yes. A two-lever quadrant can control Engines 1 and 2 as one pair and Engines 3 and 4 as the other pair.

1. Create a four-engine aircraft profile. Assign the left physical lever to Throttle1 and the right lever to Throttle2.
2. Use FSUIPC's pairing option when available. In the separate-throttle calibration section, Map 1->12, 2->34 maps the first axis to Engines 1 and 2 and the second to Engines 3 and 4. Do not also create duplicate engine assignments when this option is active.
3. Use paired direct assignments only as a fallback. If that mapping option is not exposed in your interface, assign the left axis to both Throttle1 and Throttle2, and the right axis to both Throttle3 and Throttle4, using separate assignment fields.

Keep the paired channels calibrated consistently so both engines in each pair reach idle and maximum thrust together. Four physical levers remain preferable when available because they preserve independent engine control during failures and asymmetric operations.