There is a key (E) used in the helicopters that can't be disabled. This keybinding is NOT displayed anywhere on the menu, nor in any other menu I could find.

This leads to problems like:
I wanted to change the controls of the helicopter, so Q would be Left Pedal, and E would be Right Pedal. Though this does not happen as E makes, for some reason, the helicopter shift forwards.

This does NOT happen with the default keybinds.