The Short Cut!
Looks like you might be clever enough to co-pilot the Aeronautilus! You've unlocked the Flip-n-Fly Short Cut! This will help you solve the riddle with more ease once you have found all the letters and their substitutions.
Suitcase Code
Download and print this PDF of the suitcase's code. Directions at the top of the page will tell you how to use it. It'll help track your progress as you solve the puzzle!