D.B cooper mystery!

I watched documentry on famous D.B Cooper Highjacking and found it very intersting. I got interested in knowing more about it and i noticed that a big chunk of people believe that he probably died after his jump and lost all money.
BUT, think about it for a second!! The man planned one of the most intersting robbery in the history that too just in a 30 minutes flight. I am sure he must have planned all the details very carefully. How he will enter the plane and how he wll exit. Just to think that he jumped without any proper planning on a random spot is stupidity. I mean he must have chosen the fligh to board carefully. He knew the flight path , and also the possible alternatives the plane can go to in case of less fuel. I mean nobody wll plan a Heist without a proper exit plan. So, i dont think he jumped out at any random spot , i think he must have done his calculations and survived after the jump leaving no trail behind.
May be a perfect Crime!!!