I haven't figured out if its possible to turn off "turbo" notifications in chat: TURBO ON and TURBO OFF. My HUD is enhanced for better visibility (150% font size) and therefore I've got only three lines of chat so I have to choose to turbo or to read chat. (opening chat in maximised window during turbo flight is an option, but I quickly loose track on what's happening around). As I understand there are HUD options to toggle on and off flight-assist and auto-aim notiffications that appear in chat.

If it's possible to turn those notiffications off please let me know. If not, can I ask about adding this option to game settings?

I can't help you with en/disabling this, but you could work around it; there are multiple plugins that provide turbo management features, or you could just use a turbo toggling alias.

For an alias setup, try adding these; do note that they don't like it when you change your turbo using something other than the alias, such as pressing activate to warp out. If that occurs, you might just have to double-tap whatever key/button/etc you bind as togturb

/alias TogTurb "doTurboOn"
/alias doTurboOff "+Turbo 0; alias TogTurb doTurboOn"
/alias doTurboOn "+Turbo 1; alias TogTurb doTurboOff"

then bind TogTurb to the button you want. If its a gamepad's button, use Options>Advanced>Controls>Keyboard, pick _ANY_ command and bind the key you want, and note down what the key name is (should look like JOY0BUTTON04 or something like that). Then, use /bind <your gamepad or keyboard button's ID> TogTurb

If you're using droidbuttons, just create a button and manually type in TogTurb to its command option.

It works!:D

I used multicklick, set my key on pad for turbo, then on press I wrote "togturb". In chat I entered three "/alias (...)" commands. I haven't got any feedback after entering them, but (after some misspells) now I don't have any "turbo on/off" messages anymore.

Commands are fun, thank you.