http://store.uhaul.com/product_detail.aspx?id=8725
What boxes have people used for shipping or taking a backpack on a plane? I found this one at uhaul designed for golf clubs that might do the job. This is the first year I plan to fly to a hike and have never had to deal with this before. I am thinking I will have my sister pick up a similar one on the other end for the return flight.