The 509th just refuses to target any hex for a drop. I've read the manual regarding the airborne section probably three or four times in full now and I cannot figure out why this unit will not target a hex for dropping.
Here's the unit:

Looking at my overall strategic options It's probably going to be best not to drop this unit as is anyway, but I'd still like to figure out why the game isn't letting me target a hex for this unit.
Thank you!