I have a 35L that I bought for travel to Europe. The airframe (when deflated) can make even a large / long torso pack fit into a 20" overhead bin, for the smallest carry on allowances. I don't know why more people don't buy this pack just for easy airline travel.
hushshTechnically the 60L is oversized for flights. Most full size back lengths are over the sizing limit for carryon. BUT.... If you do not fill the outer pockets, and remove a large item or two from the backpack, (take out and wear the sweater / jacket as you go through checkpoints) and roll it down / squish it to fit to size, (the airframe deflates to allow this), it will be regulation size for travel, and reset to full backpack size later.