You'll stay cool, I know you will.
Plan for a long haul.

Every read the book Endurance: Shackleton's Incredible Voyage ?

I love that book. Here's a guy who led an expedition to Antarctica, planned for a couple months, but was gone for more than 2 years. The ship was crushed in the ice. Yet the expedition lost not a single member of his crew. 2 years!

We all may need more endurance than we might think.