Today i am playing and i can confirm he is TK infantry for planes... and tk the planes he couldnt get as they try to take off.
Also he is just shooting other team players at random and then run behind others to try to create chaos.
He tend to be medic and team wound to lower our health to few percent then run away into a group (several times). And he is using the jeep to push players in their plane off the runway (and give them minus points, also several times).
I spoke to him in polish a bit and he seem to find it funny...