Was flying Kemble to Duxford yesterday and route took me overhead Upper Heyford. Its a very significant feature but did not show in planning or navigation on Skydemon display. Got caught out for a few moments untill I looked at a real map. Yes, I know I should of rehearsed the route more thoroughly, but is there any reason it does not show in SkyDemon as many much smaller disused airfields do? Sky Demon does know where it is because it finds the right blank spot on the chart if you type it in as a route. Are there many similar cases?