Anglerfish, for example, will scare the heck out of anyone — its long and crooked teeth along with a growth on its head that lures the prey is enough to instill fear even in the bravest.
I can imagine being a 17 year old kid jumping into one of these airplanes and then being thrown into combat versus another guy who's probably another 17 year old kid scared out of his mind he's trying to kill.