for over ten years. there are already some models for BE in the empires folder. atm only devs can use them ingame by typing emp_devabuse 1 into console. ofc aircraft is invis so that the abuse isnt that obvious.
Snipes, the models are mostly already done. The code is bugged for OB, It is being worked on but not top priority. some aircraft were working in 2.0 release, check the news for the 2.0 interview with mod DB and they have a pic of the aircraft in action.
In 1.08, we had aircraft for a time. You could use the console to open the aircraft build menu and build from the VF. The models were 1/16th scaled AFV's.