Went yesterday for above tests.
40% reversability with ventolin
Fev1 in 2014 = 1.07, 2015 = 1.21, 2017 = 1.11 all a bit of a mystery to me 
DLCO 2014 = 46%, 2015 = 51%, 1017 = 50% of predicted
Fit to fly showed a drop from 93% on room air to 71% on airline mix and back to 91% on airline plus supplemental o2 at 3LPM. I take this to mean that i need at least 3LPM when flying, see specialist again in August and will see what he has to say.
Thanks Sue - very interesting - please let us know what specialist says in August x
Up to now, the replies when I have asked this question have been evasive, as in "some people are better than others", not everyone copes well with hot weather, there is a risk of picking up infections in the recycled air on the plane.
So I have not been on a plane in twenty years. I am told I have mild/moderate, done in March, fev 60%. But only a very vague notion of what that means.
Reading your post was very encouraging.
It can be tricky as different people can have different reactions to the same situation. Plane air is safe with regard to infection and not actually recycled as such, though that said whenever we are in an enclosed situation such as plane, bus, train etc we can pick up bugs from those around us. I have been on cruises and always come home with a chest infection. When I travel I carry antibiotics to use at the first sign of an infection and this has helped.
When flying the air pressure is what can make a difference for anyone with lung problems. As I said in my previous post my O2 sats can drop from 93 to 70 on cabin air, so always a good idea to check.
Don't stop doing the things you want to do, life is for living even if we have to make some adaptations to how we do these things. Get out there, spread your wings and enjoy.
Spirometry results
recently diagnosed mild COPD after spirometry
Spirometry results good
Spirometry and COPD/Emphysema. 
CT Scan vs Spirometry
