If plane propellers get introduced, it should be a rare rarity one directional rotor movement part with a weak constant melee effect during movement, with a boost to forward/side/backward movement based on the orientation.
I believe it’s best to be a Nomad part.
They’ll need much larger maps to make airplanes practical. Then again, airplanes just don’t fit into the idea of Crossout (helicopters don’t either, to be honest).
Did they say they’re adding airplane propellors?
I agree, I made a plane with 8 hermes booster rockets on it and most maps are too small to use it. 
(It’s on PC exhibition if you want to try it though!!)
I don’t think we need planes (we’d need wings and rudders and bigger maps).
But I could see these kinds of propellers:
They could work like steerable boosters, and do melee damage if someone runs into it.
Who needs propellers when we have stupid jet engines pointing down?
aka hovers.
TBF hovers behave like a hovercraft now so not really needed
if they add planes to crossout you may as well uninstall and go to war thunder
Pusher prop. Nothing big just something to speed up rotors slightly and or ground based vehicles.