All Coast Guard aircraft shall guard which emergency frequencies?

• A. 121.5, 156.8 and 243.0 MHz
• B. 121.5 and 156.8 MHz
• C. 243.0 MHz
• D. 118.0 MHz

Answer: (A)

Guarding these emergency frequencies means continuously monitoring them and being ready to respond to distress calls from any source. The VHF aviation distress frequency 121.5 MHz is the international standard pilots use to call for immediate help, so keeping eyes and ears on it ensures airborne emergencies are heard promptly. The maritime distress channel 156.8 MHz (Channel 16) is used by ships and coast stations to call for help and coordinate SAR events at sea, so monitoring it lets Coast Guard aircraft detect mariners in distress or coordinate with vessels. The UHF emergency frequency 243.0 MHz serves as the aviation/military counterpart, especially useful in joint operations or where UHF gear is in use.

Together, these three frequencies provide the broadest coverage across air and sea environments and civilian and military users. Missing any one of them could mean missing a distress signal, which is why guarding all three is the standard practice. The other options omit one or more of these critical bands, or include a non-emergency frequency like 118.0 MHz, which is not designated for emergency distress.