🔍 Key Concepts

• Emergency Locator Transmitters (ELTs) are used on aircraft, not ships, but mariners are expected to recognize their distress frequencies • Older aviation distress beacons used two VHF frequencies related to marine/aviation distress • Modern satellite alerting for ELTs involves a 406 MHz signal received by COSPAS-SARSAT satellites

💭 Think About

• Which of these frequencies are traditionally associated with manned voice distress and homing (civilian and military)? • Which frequency in the list is specifically used for modern digital satellite alerting of distress beacons (EPIRBs, PLBs, and ELTs)? • Think about how older ELTs were designed versus newer 406 MHz ELTs—what combination of frequencies would make sense for both local homing and satellite detection?

✅ Before You Answer

• Identify which options include both the traditional distress/homing frequencies and the modern 406 MHz satellite alerting frequency • Eliminate any option that contains only the old analog distress frequencies without 406 MHz • Confirm that the choice you pick matches what you’ve heard about newer 406 MHz ELTs and how SAR (search and rescue) units home in on them using 121.5 MHz