The TWSBI pens tend to do well. A pen that doesn’t do well is the Pilot Vanishing Point.
I think the comment on what angle you keep it at until you reach flight level is spot on. If you can store it so that the air bubble is up and the feed doesn’t have a huge amount of ink in it, it should be okay.
Some variations of vacuum fillers also have a piston that you unscrew to let ink flow from the reservoir, but close when you fly.
(Sorry if this is a bit vague. I’m more of a user of fountain pens rather than a collector so I tend not to geek out as much when it comes to the technical details. I mostly tend to choose pens based on what kind of writing I’m doing :-))
I think the comment on what angle you keep it at until you reach flight level is spot on. If you can store it so that the air bubble is up and the feed doesn’t have a huge amount of ink in it, it should be okay.
Some variations of vacuum fillers also have a piston that you unscrew to let ink flow from the reservoir, but close when you fly.
(Sorry if this is a bit vague. I’m more of a user of fountain pens rather than a collector so I tend not to geek out as much when it comes to the technical details. I mostly tend to choose pens based on what kind of writing I’m doing :-))