I use my normal flight-kit..
Saitek Pro-Flight Rudder Pedals
...and I'm bitterly disappointed that, despite Naturalpoint sending the required software to the Flight team, my TrackIR v5.0 is unused...
Given that it's a flight 'game' and that in the Steerman aircraft they let you use your middle mouse wheel to control your view, it's staggering they didn't code in such a simple piece of software. TrackIR is the greatest thing to ever happen to flight sims.