Article 1 · Alert process
What happens when a beacon activates?
Follow a PLB, ELT or EPIRB alert through Cospas-Sarsat and rescue coordination—and learn why the person should remain with the beacon.
Read the article →Field knowledge
SAR beacon-location resources.
Source-led explanations of 406 MHz distress alerting, 121.5 MHz final homing and the equipment used to locate ELTs, EPIRBs and PLBs.
Article 2 · Ground response
How ground teams locate the beacon
Move from authorized coordinates to live signal observations, bearings and 121.5 MHz final homing.
Read the article →Article 3 · Current tools
406 and 121.5 MHz locating equipment
Compare handheld, portable, installed and general-purpose field equipment by the functions each performs.
Read the article →Core concept
406 MHz vs. 121.5 MHz
Understand why satellite alerting, field detection and live directional homing are related—but different—jobs.
Read the guide →Field note
Air-ground beacon-location exercise
Lessons from a coordinated Hawaiʻi exercise using air and ground resources to prosecute a training beacon.
Read the field note →System comparison
Guardian Rescue systems
Compare Guardian, Overwatch406 and Guardian Pro by frequency, field role and documented capability.
Compare systems →The Last Mile After a 406 Alert
Why location information, functioning homing signals and trained field teams all matter after the alert.
Read the article →