Never bring your fountain pens with you when you travel by air.
First, you might lose them.
Second, they might get stolen.
Third, customs and immigration forms will accept writing only in black or blue ballpoint ink. Should you insist on using black or blue fountain pen ink, the ink will feather because the paper used for such forms is substandard, as is the paper used in bank forms (gone are the days when banks used fountain pens and really classy paper).
Finally, the pressure inside an airplane will cause your ink converters to leak or explode (and say goodbye to those converters afterward).