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Federal Communications Commission
445 12th St., S.W.
Washington, D.C. 20554
News Media Information 202 / 418-0500
TTY: 1-888-835-5322
DA 17-747
August 8, 2017
Enforcement Advisory No. 2017-01
121.500 MHz Reserved for Emergency Use Only
The Enforcement Bureau of the Federal Communications Commission (FCC), in coordination with the 
Federal Aviation Administration (FAA), has been investigating instances of misuse of, and harmful 
interference to, frequency 121.500 MHz, which the FCC has set aside for emergency and distress 
communications.  The FCC regulates aviation communications in cooperation with the FAA, which, 
among other things, continuously monitors distress frequencies to protect life and property.  The FAA 
has reported to the FCC that the FAA’s ability to monitor aviation channel 121.500 MHz for actual 
emergencies is being impaired by an increase in the use of 121.500 MHz for non-emergency 
communications.  The Enforcement Bureau will aggressively enforce the rules related to aviation radio 
operations.  Ensuring the integrity of safety and distress frequencies is vital to safeguarding lives and 
What Should You Know?  
Aircraft operating domestically are authorized to operate VHF aviation radios, radar, and emergency 
locator transmitters (ELTs) without having to obtain individual licenses from the FCC, while aircraft 
operating internationally must hold a license issued by the FCC.  In both cases, however, airmen1 must 
follow the operating procedures specified in Part 87 of the FCC’s rules.2  
1 For this Enforcement Advisory, we use the term “airman” as that term is defined in the Federal 
Aviation Act of 1958, as amended.  There, Congress defined the term “airman” as “an individual—(A) in 
command, or as pilot, mechanic, or member of the crew, who navigates aircraft when under way; (B) . . . 
who is directly in charge of inspecting, maintaining, overhauling, or repairing aircraft, aircraft engines, 
propellers, or appliances; or (C) who serves as an aircraft dispatcher or air traffic control-tower 
operator.”  49 U.S.C. § 40102(a)(8).
2 47 CFR § 87.1 et seq.
Of particular importance, Section 87.173 of the FCC’s rules mandates that 121.500 MHz be used solely 
for emergency and distress purposes.3 The FAA continually monitors 121.500 MHz and treats any 
distress call received as an emergency to be investigated immediately.  Prohibited communications on 
121.500 MHz include: false distress or emergency messages, superfluous communications, messages 
containing obscene, indecent, or profane words or meaning, general calls (calls not addressed to a 
particular station), routine messages, radio tests, and transmission of recorded audio (such as music or 
spoken text).  Misuse of 121.500 MHz can distract FAA personnel monitoring the channel from hearing 
transmissions related to actual emergencies and, as a result, poses a threat to life and property.  
What Happens if Users Do Not Comply with the FCC’s Rules? 
Interference to an aviation distress and safety frequency, including 121.500 MHz, is a violation of the 
most critical nature, with the potential to obscure genuine distress transmissions.  The Enforcement 
Bureau intends to aggressively enforce violations of the FCC’s aviation radio communications rules. 
Violators may be subject to the penalties authorized by the Communications Act, including, but not 
limited to, substantial monetary fines (up to $19,246 per single violation and up to $144,344 for an 
ongoing violation), an in rem action to seize the offending radio equipment, and criminal sanctions.  
What Should You Do?  
The FCC rules governing the aviation radio service are designed to protect both your life and the lives 
of those around you – fellow airmen and the public.  Please take the time to learn the FCC rules 
governing proper radio operation and comply with them.  Airmen should note that 122.750 MHz is 
available for air-to-air communications.4
Need more information?  
For additional information regarding enforcement of the aviation radio rules, proper use of aviation 
radio frequencies, and licensing of aircraft radio stations, please visit the FCC website at  Media inquiries should be directed to Will Wiquist at (202) 418-
0509 or  
To file a complaint, visit or call 1-888-CALL-FCC.  
To request materials in accessible formats for people with disabilities (Braille, large print, electronic files, 
audio format), send an e-mail to or call the Consumer & Governmental Affairs Bureau 
at 202-418-0530 (voice), (202) 418-0432 (TTY).  You may also contact the Enforcement Bureau on its 
TTY line at (202) 418-1148 for further information about this Enforcement Advisory, or the FCC on its 
TTY line at 1-888-TELL-FCC (1-888-835-5322) for further information about the aviation radio rules.
Issued by: Chief, Enforcement Bureau
3 47 CFR §§ 87.173, 87.187(k).  Frequency 121.500 MHz also is used for maritime distress and search 
and rescue communications, and for direction-finding with respect to emergency radiobeacons at sea 
and on land.  See 47 CFR §§ 80.1077, 87.199(b), 95.1402(a), 95.1403(b).
4 47 CFR § 87.187(j).