Hi, quick list
Select all engines
toggle engine (start/stop)
Manual gear up & down for Wildcats and others
toggle wing fold
toggle arrester hook
dive brakes
center track IR
nav lights
supercharger up
supercharger down
padlock enemy ground (very handy if your eyesight isnt as good as it should be)
drop tanks
I am sure that there are some more
it might be worth getting a Saitek Pro gamer control pad it gives another 20 buttons more if you use the modes.
Place them where it suits you, but it can be hard to remember which button does what