No problem. Yeah the planes work fine, I assume any modded vehicle does.
As far as I know that's a common issue with all mods that add something to another research. You can unresearch tech with the console:
/c game.player.force.technologies['automobilism'].researched=false; game.player.force.set_saved_technology_progress('automobilism', 0)
This will disable achievements. Then just research it again or do
/c game.player.force.technologies['automobilism'].researched=true
Other then that, you can open the mod zip, open recipe.lua (inside the prototype folder) and delete the last two lines, that removes the research requirement. As I don't plan any updates no worries about it getting changed back.
