There is an out patient test offered at some hospitals that can measure your ability to be in a pressurized cabin. Your care team will be able to tell you how to get that test if it is appropriate for you. I made a personal decision not to fly anymore not only due to risks but also personal comfort. (Access to bathrooms, edema issues, needing to travel with a walker, etc.)

Sid:
There is only one person who can answer your question as to whether you can fly or not and that is your PAH Specialist. We are all unique and our disease affects us differently. I personally have flown since my diagnosis in 2012 but many on this site have been told not to. There are risks involved in being at a high altitude and one of them is low oxygen. Not sure if you are on supplemental oxygen or not as that can make a difference. Airlines have certain requirements if you are. So I would be checking with my PAH Specialist if I were you.

How great that the test is so available to patients. Here I think there are just a few hospitals offering the test.

Ask your Doc to test you for flying..
I live in Naples Florida...
My Pulmonary Doc has a machine for testing PAH patients for flying!