Only works in the DA, offline, or in KOTH. As far as I know.
1. Go to Map Keys. In Mode 1 set key * (on number pad) to Switch to Mode 3
2. Then switch to Mode 3 and set key / (on number pad) to Switch to Mode 1
(That's so if you get stuck in Mode 3 you can flip back without ending sortie)
3. Go to Map Controllers. Switch to Mode 3. On your joystick under Views set a button to View CM Eye Move Forward ( I use my Look Up button)
4. Still in Mode 3 set a button to View CM Eye Move Back (I use my Look Down button)
5. Pretty sure you don't have to set your throttle for Mode 3 but check it anyway. Should be Analog Inputs Throttle 1
Go offline, or DA. Hit F5, then * Throttle up and press Look Up (or whatever you set to CM Eye Move Forward) And etc.