24. Transmitter Overdrive#

FS One lets you record (start and stop) and then play back a time slice of your transmitter stick inputs. This feature is called Tx Overdrive because the playback “drives” the control inputs (over top of your own) for the length of your recording, and the starting point of the aircraft begins with where you started your stick recording. When finished, control is then returned to you.

Here are some examples of how this can be used:

  • Taxi an airplane to your favorite point for takeoff, record sticks for an instant and use that recording to start over and over again in the same position. Effectively, this creates a “bookmark” position, also called initial conditions.

  • Fly up in a thermal, and “bookmark” that position to restart repeatedly from that location after you’ve flown around for awhile.

  • Record some stick inputs through a maneuver, and then edit the aircraft aerodynamics to examine the effect in a systematic way by playing back the same pilot stick inputs, including the starting conditions, i.e. initial conditions - aircraft speed, position, and orientation.

The main Tx Overdrive keys are the yellow ones on the Keymap Card:

Image of the main tx overdrive keys.

To start recording your stick inputs:

  • Press [

After any length of time flying or doing nothing, finish and save the stick recording:

  • Press ]

To play back the recording:

  • Press ,

The airplane now flies in response to your recorded stick movements. The stick recording also records your switch inputs, e.g. landing gear switch.

The recording is saved for that aircraft. If you stop flying, change something in the menus, and once more click Fly, then the recording can be played back again with , , or you can create a new recording with [ and ] . A new recording will overwrite the prior one.


Tx Overdrive saves the stick position and when played back those same stick positions are being run through the physics engine. So the recording is not a “flight recording” that is saving a snippet of your flight trajectory. It saves a snippet of your controls.

To stop playing back a stick recording before it completely finishes on its own:

  • Press .

A stick playback always begins with some initial conditions, namely the aircraft position, orientation, and speed - the starting point. To begin with, these are the conditions at the time you press [ (Save Initial Conditions key). But as described next, you can reset these initial conditions (while still using the original stick recording).

To change the initial conditions:

  • Fly until the conditions are what you want. For example, fly straight and level, 30 feet above the runway, at 20 mph. Or taxi to some new position (rolling or stopped).

  • Then press \ to save the initial conditions. The next time you press , to play back, the airplane will start at the new conditions where you press \ and then play back your stick recording.

To “place a bookmark” (a position) in a flight that you can return to:

  • Leave the aircraft parked.

  • Press [ and ] in rapid succession. This creates a very short stick recording, say 0.1 sec.

  • Fly to where you want to “bookmark” the position (whether in flight, taxing, or parked).

  • Press \ to save the initial conditions. Now, whenever you press , , you will start at that “bookmark.” The recording will play back in an instant (the 0.1 sec) and leave you in control at that “bookmarked” position.

    If you made the “bookmark” while on final approach, you can use this to practice landings without having to take off each time. If you made it while hovering, you can quickly zap your airplane into a hover, the “bookmark” that you created. Tricks like this let you make the most of any practice session.

  • If you start over with a new [ and ] sequence, it will reset the initial conditions to the start of that recording. Use \ again if you want to reposition the starting point.

To abort a recording in progress, without replacing the previous recording:

  • Press 0 on the numeric keypad.

Image of the transmitter overdrive keyboard keys.

Note: If you are using the on-screen Transmitter Display ( E ) widget, then during playback the on-screen transmitter sticks will still show your current stick inputs, and not the active Tx overdrive recording being used in the physics.