IN JUNE 2022, I HELPED SOME friends deliver a high-performance sailboat from Ketchikan, Alaska, to Seattle. Our crew was experienced, so we opted to sail west of Vancouver Island. Those waters are frigid, and the shorelines are desolate, so I carried two personal locator beacons. ¶ The first PLB, an Ocean Signal MOB1, was rigged inside my Spinlock Deckvest 6D life jacket, ready to self-activate and transmit my position via the automatic identification system if the jacket inflated. The second PLB, a McMurdo FastFind 220, resided in a case on my jacket. If manually activated, it would transmit 406-megahertz satellite signals to the international Cospas-Sarsat program, for routing to search-and-rescue authorities. ¶ Back then, this two-PLB setup was the gold standard, but it used only GPS (not the entire global…