These are brilliant tips and thanks. I have been stuck on 495 airports and after about 10 short hops thins evening it moved to 497. Looks like i am going to have to turm real weather off as well.
All this explains while after landing at over 900 airports its not recording nearly 50% of them.
Thanks to you @Zathrus63 Now only the Decathlon Acheievment to do
Here are some tips i found for Jack of All Planes
https://forums.flightsimulator.com/t/jack-of-all-planes-achievement/370631