My first try was in his yak and that did not work.
But in your -6a, no problem? How often do you fly? Perhaps someone else with this will chime in..
I would not admit to Claustrophobia, but there are places I will not go.
Now, on to how to solve the problem. With absolutely NO empirical evidence to back this up, I recommend plenty of cool, fresh air be directed/blown onto the affected person. With me, warm, stale air makes the problem a hundred times worse. I feel suffocated. Flying on cool, crisp days is the way to go....or maybe some type of portable/lightweight air conditioner (or substitute)...Just my 0.02.
I think for most folks who built theirs, if they can survive riveting the tail cone of an -8, they’re probably not going to have claustrophobia problems. I wasn’t sure if I could get out of there once I was in.