Fountain pen users love to travel just as much as everyone else, so why not travel with your fountain pen even when you fly! There is the possibility that a fountain pen will leak in-flight when the air pressure in the plane cabin drops and the higher air pressure inside the pen forces ink out of the nib. However, there are some simple steps that can be taken to reduce or eliminate this risk.
First of all, it can help to travel with your fountain pen either completely full of ink (the air expands, not the ink) or completely empty (no ink, no leaks). Using cartridges with your pen is practical because you can travel with a new cartridge and an empty pen and insert the cartridge after you land.
It is best if you bring your fountain pens in your carry-on baggage instead of putting them inside your checked bags. For extra safety, put them inside ziploc bags and store them with the nib pointing up.
I’ve flown with both LAMY and Preppy fountain pens with varying amounts of ink in the cartridges and not had any problems other than a tiny bit of extra ink appearing on the LAMY nib. Alan has flown with a Kaweco Sport fountain pen containing a full cartridge as well as LAMY pens with only partially full cartridges and not had any leaks. The only problem Alan has encountered was with an eyedropper fill Kaweco pen that was not completely full of ink. This pen leaked small beads of ink during the flight. Do any of you have a flying with fountain pen experience that you would like to share with us?