Don White wrote:
Not sure if it's practical to set your autopilot and then set your radar to
issue an audio alarm when something comes within 10 miles or so.



Audio alarms for radar have a tendency to sound, based on "sea -
return", so many people all too often turn them off.
If you plan to singlehand, add an AIS with CPA alarms. No guarantees,
but coupled with radar, it might help increase your safety factor.....
course, this doesn't address the surfacing sub issue.......

nothing will be foolproof