AIM 8/15/19  Section 5. Aircraft Rescue and Fire Fighting Communications 6 − 5 − 1. Discrete Emergency Frequency 6 − 5 − 2. Radio Call Signs 6 − 5 − 3. ARFF Emergency Hand Signals EXAMPLE − a. Direct contact between an emergency aircraft flight crew, Aircraft Rescue and Fire Fighting Incident Commander (ARFF IC), and the Airport Traffic Control Tower (ATCT), is possible on an aeronautical radio frequency (Discrete Emergency Frequency [DEF]), designated by Air Traffic Control (ATC) from the operational frequencies assigned to that facility. b. Emergency aircraft at airports without an ATCT, (or when the ATCT is closed), may contact the ARFF IC (if ARFF service is provided), on the Common Traffic Advisory Frequency  (CTAF) published for the airport or the civil emergency frequency  121.5 MHz. Preferred radio call sign for the ARFF IC is “(location/facility)  Command ” when communica- ting with the flight crew and the FAA ATCT. LAX Command. Washington Command. In the event that electronic communications cannot be maintained between the ARFF IC and the flight crew, standard emergency hand signals as depicted in FIG 6 − 5 − 1 through FIG 6 − 5 − 3 should be used. These hand signals should be known and understood by all cockpit and cabin aircrew, and all ARFF firefighters. FIG 6 − 5 − 1 Recommend Evacuation FIG 6 − 5 − 2 Recommend Stop 6 − 5 − 1 Aircraft Rescue and Fire Fighting Communications