No, they boats will see each other at a little under 10 miles. Same as with landfall, you can see mountain tops long before you can see the beach.
AIS and VHF are line of sight. Once the other antenna pokes above the horizon your AIS will see it. There are a few other considerations, like atmospheric conditions that can lengthen or shorten the distance, but those are somewhat rare.
Transmission power does have an impact, I think AIS transmits at about 2 watts, however, transmitting a data burst is more efficient than transmitting analog voice, which is why VHFs are 25 watts. It is also why DSC emergency signals are much better than voice Maydays.
AIS and VHF are line of sight. Once the other antenna pokes above the horizon your AIS will see it. There are a few other considerations, like atmospheric conditions that can lengthen or shorten the distance, but those are somewhat rare.
Transmission power does have an impact, I think AIS transmits at about 2 watts, however, transmitting a data burst is more efficient than transmitting analog voice, which is why VHFs are 25 watts. It is also why DSC emergency signals are much better than voice Maydays.