I forget how we arrived at our figures in FotRSU - but I do remember is was NOT scientific by any stretch of the imagination... We considerably shortened the "Maximum Aircraft Range" to less than 1000km - Stock is 2000km - made a "world" of difference... sorry for the pun...
- Check this out:
https://cimsec.org/close-the-gaps-ai...-and-tomorrow/
There is "historical" info there, along with a little map.