Radio Communication Procedures
When and How to Talk
sUA operations in controlled airspace may require communication with ATC, especially when operating under a waiver or in areas where LAANC authorization includes a requirement to contact the facility. Use standard phraseology: identify yourself, your location, your altitude, and your intentions. Example: "Tower, drone N12345, one mile south of the field at 300 feet, requesting operations in the traffic pattern area." Keep transmissions brief and use the phonetic alphabet and standard numbers.
Common Frequencies and Calls
Know that CTAF is used at non-towered airports to announce intentions, and that ATC frequencies are published on sectionals and in the Chart Supplement. For sUA, you generally will not be talking on CTAF unless coordinating with manned traffic; more often you monitor. When you do transmit, state "drone" or "unmanned aircraft" so manned pilots can locate you.
Emergencies and Lost Comms
If you lose radio contact, follow your authorization's procedures and land or exit the area as directed. Declare an emergency if the sUA creates a hazard: "Mayday" or "Pan-Pan" as appropriate, with location and nature of the problem.
Traps
Questions test whether you must monitor CTAF at a non-towered airport (not required for sUA but good practice) and whether radio communication replaces ATC authorization (it does not). Another trap: using the wrong frequency or identifying as a manned aircraft.
Rule of Thumb
"Identify, locate, intend." Every transmission should say who you are, where you are, and what you plan to do - and include the word "drone."