Durk reminded me of this - when we're missing procedures data (the common case), synthesise a plausible (but possibly dangerously unrealistic) departure and approach. Will work fine for airports in gentle terrain, and likely kill you at challenging airports. You have been warned.
Cache the parsed navigation and airport data in a binary file to reduce
startup times and memory consumption (since only referenced FGPositioned
elements are held in memory).
Data will be reimported when the mod-time of any input file is changed.
If a global file is changed (nav.dat, awy.dat, apt.dat, etc), the cache
will be completely rebuilt, which takes approximately 30 seconds on
moderate hardware. (Future work may reduce this).
Convert the route-manager to use a flight-plan internally, and expose
flightplan, leg and procedure data to Nasal. Move the Level-D parser
into its own file.