If I remember the radar formula correctly (and I might not be), the maximum range is linear in RCS^(1/4). So if 470 km for 1 m2 is correct, it would mean 264 km for 0.1 m2, 149 km for 0.01, and 84 km for 0.001. I don't know what the RCS of F-35 is in the S-band, but there seems to be a good...