Flying With Fountain Pens - SOLVED!

Just like anyone new in fountain pens you hear that you can't take them on an airplane or else they will leak everywhere. I've taken them on planes a few times with mixed results. After searching online you read MANY different tips and tricks, some of which contradict each other.
So I decided to test all this stuff out. I built a home made vacuum chamber to simulate flying on an airplane. Then started testing pens. Now I think I've found out how you can safely fly with pretty much any pen, any filler type, with any ink level if you follow a few steps.

Let me know what you think in the comments! I had a bunch of fun doing this test, DoodleBud Atmospheric Gauge test (DBAG for short), and am happy to answer any questions best I can.

Let me know what other possible questions/tests you'd like to see!