Yes I realize you and a lot of others BELIEVE he intended to jump in Seattle area ! However it’s just a belief and actually nobody knows where he planned to jump. I believe there are far more reasons to jump elsewhere. The Woodland, Battleground area is less populated and of course far closer to where his caper originated. Why did he need an escape vehicle ? Well that’s a no brainer unless he had an accomplice. I would think he didn’t go to all this work, planning and danger without having a plan for escaping !
The obvious question then becomes: How did Cooper know that they would fly over Woodland, Battleground or Portland?
How did Cooper know that the pilots didn't take a route along the coast--this was actually discussed--or a route that brought them over to the Tri-Cities area then down to Reno from there?
Moreover, what does Cooper do with his escape vehicle in Portland if he has to abort the hijacking? Does he turn right around and attempt to fly back to Portland that evening? If he can't get a flight back to Portland that evening what is he going to do in Seattle?
Furthermore, doesn't his choice of attire become questionable if he actually planned to jump over Woodland or Battleground?
Truth be told, Cooper didn't care what route they took to Reno because he was planning on jumping in the Seattle area. Additionally, he also wasn't concerned about where he was going to stay in Seattle if he had to abort, or his attire jumping in the outskirts of Seattle.