That's the same thing I thought. Most likely a Search and Rescue operation. I was a P3 Orion flight engineer. That plane did maritime patrol missions at low altitude over the water. We would fly at 200ft for hours doing tracks like that either on a S&R mission or hunting submarines. So maybe they were tracking an enemy sub instead of a S&R mission. Either way it looks normal to me.
It looks like a search grid
That's the same thing I thought. Most likely a Search and Rescue operation. I was a P3 Orion flight engineer. That plane did maritime patrol missions at low altitude over the water. We would fly at 200ft for hours doing tracks like that either on a S&R mission or hunting submarines. So maybe they were tracking an enemy sub instead of a S&R mission. Either way it looks normal to me.
International waters begins at 12 miles from the shoreline. I have been on missions that tracked submarines within 50 miles of our border before.