This and similar statements are probably coming from the fact that you can't see your own darbar.
But number of planes in a sector is irrelevant. Each plane above min dot alt will make one, each plane above min sector alt will contribute to the darbar.
Minimum altitudes are always AGL (above ground level), and terrain features (mountains) between you and the enemy radar do not protect you from being detected
noe's are mostly found because at least 1 guy will keep breaking dar. that and the fact that it's hard not to notice a base blinking with nobody around. all is needed is about 10 seconds since noe went above dar for the alarm to be given and fighters to scramble.
here are some things that I look for to find noe's.
-time of play: vtards were famous for doing only noe's late at night.
-lots of people in tower
-lots of people suddenly gone from the tower
-look around and find bases most likely to spawn noe's kill their ords if they get resupplied, wait for noe from there.
-if there has been one noe that same country is more than likely to spawn another noe, specially if lots of players stay in the tower.
in some maps it's so easy to discover noe's that there's lots of rumors about spies. also I notice some noe's will ignore all the fighters till they drop their ords, this is bad as we can fly right by them on the way to kill the goons. target the goons noe is a fail.
semp