Do you have a racing setup, by any chance? I found that my gas and brake pedal work as rudder pedals. All of my sims recognize them as rudder pedals. That surprised me.
"From our orbital vantage point, we observe an earth without borders, full of peace, beauty and magnificence, and we pray that humanity as a whole can imagine a borderless world as we see it, and strive to live as one in peace."
Astronaut William C. McCool RIP, January 29, 2003 - Space Shuttle Columbia