Subsets available in Ideal Flight:On the Startup page popup menu, choose the "Maintain Indexes" submenu, "Create Subset Files" item. Popup the menu again and see the item is checked, now start the "Navigation and Scenery Index". It will take a lot longer so go and make a cup of Tea. When it has done it has created more than a Dozen airport subsets, for example "Water Strips Airports" subset loaded into the Flight Generator page Enables only those Airports with Water strips.
A screenshot of the subsets dropdown list in the latest version showing the new Tour item at the end of the list:
Subsets generated include:
Add-on Airports, AIRAC Common Subset, Cargo Parking Airports, Edge Lit Strips Airports,
Filtered Airports, Fuel Parking Airports, Helipad Airports, Hub Airports,
ILS Airports, Lit Strips Airports, Loose Strips Airports, Military Parking Airports,
No Parking Airports, Parking Codes Airports, Soft Strips Airports, Tower Frequency Airports,
Unlit Strips Airports, VASI Strips Airports, and Water Strips Airports.