PERSONAL LOCATOR BEACONS
At one time, personal locator beacons served only to send a one-way message via satellite to rescue personnel. The wait for rescue is always painful, but more so when you don’t know if anybody knows you need it. Today, however, PLBs have improved astronomically because they can also use satellites for other communications, such as texts, family tracking and the ability to summon non-emergency towing assistance. Some can even receive a message, such as “help is on the way.”
We cold-started each device and initiated a test message to see how long it took to link to its satellite constellation and receive the message via Gmail. We assume this process should approximate the time needed to send and receive an SOS.