4/20/23 

AIM 

Section 3.  Distress and Urgency Procedures 

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1.  Distress and Urgency Communications 

a. 

A pilot who encounters a 

distress

 or 

urgency

 condition can obtain assistance simply by contacting the air 

traffic facility or other agency in whose area of responsibility the aircraft is operating, stating the nature of the 

difficulty, pilot’s intentions and assistance desired. 

Distress

 and 

urgency

 communications procedures are 

prescribed by the International Civil Aviation Organization (ICAO), however, and have decided advantages over 

the informal procedure described above. 

b. 

Distress

 and 

urgency

 communications procedures discussed in the following paragraphs relate to the use 

of air ground voice communications. 

c. 

The initial communication, and if considered necessary, any subsequent transmissions by an aircraft in 

distress

 should begin with the signal MAYDAY, preferably repeated three times. The signal PAN

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PAN should 

be used in the same manner for an 

urgency

 condition. 

d. 

Distress

 communications have absolute priority over all other communications, and the word MAYDAY 

commands radio silence on the frequency in use. 

Urgency

 communications have priority over all other 

communications except 

distress,

 and the word PAN

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PAN warns other stations not to interfere with 

urgency 

transmissions. 

e. 

Normally, the station addressed will be the air traffic facility or other agency providing air traffic services, 

on the frequency in use at the time. If the pilot is not communicating and receiving services, the station to be called 

will normally be the air traffic facility or other agency in whose area of responsibility the aircraft is operating, 

on the appropriate assigned frequency. If the station addressed does not respond, or if time or the situation 

dictates, the 

distress

 or 

urgency

 message may be broadcast, or a collect call may be used, addressing “Any Station 

(Tower)(Radio)(Radar).” 

f. 

The station addressed should immediately acknowledge a 

distress

 or 

urgency

 message, provide assistance, 

coordinate and direct the activities of assisting facilities, and alert the appropriate search and rescue coordinator 

if warranted. Responsibility will be transferred to another station only if better handling will result. 

g. 

All other stations, aircraft and ground, will continue to listen until it is evident that assistance is being 

provided. If any station becomes aware that the station being called either has not received a 

distress

 or 

urgency 

message, or cannot communicate with the aircraft in difficulty, it will attempt to contact the aircraft and provide 

assistance. 

h. 

Although the frequency in use or other frequencies assigned by ATC are preferable, the following 

emergency frequencies can be used for distress or urgency communications, if necessary or desirable: 

121.5 MHz and 243.0 MHz. 

Both have a range generally limited to line of sight. 121.5 MHz is guarded by 

direction finding stations and some military and civil aircraft. 243.0 MHz is guarded by military aircraft. Both 

121.5 MHz and 243.0 MHz are guarded by military towers, most civil towers, and radar facilities. Normally 

ARTCC emergency frequency capability does not extend to radar coverage limits. If an ARTCC does not respond 

when called on 121.5 MHz or 243.0 MHz, call the nearest tower. 

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2.  Obtaining Emergency Assistance 

a. 

A pilot in any 

distress

 or 

urgency

 condition should 

immediately

 take the following action, not necessarily 

in the order listed, to obtain assistance: 

1. 

Climb, if possible, for improved communications, and better radar and direction finding detection. 

However, it must be understood that unauthorized climb or descent under IFR conditions within controlled 

airspace is prohibited, except as permitted by 14 CFR Section 91.3(b). 

Distress and Urgency Procedures 

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