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6/17/21 

AIM 

NOTE

 

Some Alaska FSSs are open part time and/or seasonally. 

c. 

Pilots should notify controllers on initial 

contact that they have received the Alaska FSSs 
AFIS broadcast by repeating the phonetic alphabetic 
letter appended to the broadcast. 

EXAMPLE

 

“Information Alpha received.” 

d. 

While it is a good operating practice for pilots 

to make use of the Alaska FSS AFIS broadcast where 
it is available, some pilots use the phrase “have 
numbers” in communications with the FSS. Use of 
this phrase means that the pilot has received wind, 
runway, and altimeter information ONLY and the 
Alaska FSS does not have to repeat this information. 
It does not indicate receipt of the AFIS broadcast and 
should never be used for this purpose. 

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15.  Radar Traffic Information Service 

This is a service provided by radar ATC facilities. 
Pilots receiving this service are advised of any radar 
target observed on the radar display which may be in 
such proximity to the position of their aircraft or its 
intended route of flight that it warrants their attention. 
This service is not intended to relieve the pilot of the 
responsibility for continual vigilance to see and avoid 
other aircraft. 

a.  Purpose of the Service 

1. 

The issuance of traffic information as 

observed on a radar display is based on the principle 
of assisting and advising a pilot that a particular radar 
target’s position and track indicates it may intersect or 
pass in such proximity to that pilot’s intended flight 
path that it warrants attention. This is to alert the pilot 
to the traffic, to be on the lookout for it, and thereby 
be in a better position to take appropriate action 
should the need arise. 

2. 

Pilots are reminded that the surveillance radar 

used by ATC does not provide altitude information 
unless the aircraft is equipped with Mode C and the 
radar facility is capable of displaying altitude 
information. 

b.  Provisions of the Service 

1. 

Many factors, such as limitations of the radar, 

volume of traffic, controller workload and commu-
nications frequency congestion, could prevent the 
controller from providing this service. Controllers 

possess complete discretion for determining whether 
they are able to provide or continue to provide this 
service in a specific case. The controller’s reason 
against providing or continuing to provide the service 
in a particular case is not subject to question nor need 
it be communicated to the pilot. In other words, the 
provision of this service is entirely dependent upon 
whether controllers believe they are in a position to 
provide it. Traffic information is routinely provided 
to all aircraft operating on IFR flight plans except 
when the pilot declines the service, or the pilot is 
operating within Class A airspace. Traffic informa-
tion may be provided to flights not operating on IFR 
flight plans when requested by pilots of such flights. 

NOTE

 

Radar ATC facilities normally display and monitor both 
primary and secondary radar as well as ADS

B, except 

that secondary radar or ADS

B may be used as the sole 

display source in Class A airspace, and under some 
circumstances outside of Class A airspace (beyond 
primary coverage and in en route areas where only 
secondary and/or ADS

B is available). Secondary radar 

and/or ADS

B may also be used outside Class A airspace 

as the sole display source when the primary radar is 
temporarily unusable or out of service. Pilots in contact 
with the affected ATC facility are normally advised when 
a temporary outage occurs; i.e., “primary radar out of 
service; traffic advisories available on transponder or 
ADS

B aircraft only.” This means simply that only aircraft 

that have transponders and ADS

B installed and in use will 

be depicted on ATC displays when the primary and/or 
secondary radar is temporarily out of service. 

2. 

When receiving VFR radar advisory service, 

pilots should monitor the assigned frequency at all 
times. This is to preclude controllers’ concern for 
radio failure or emergency assistance to aircraft under 
the controller’s jurisdiction. VFR radar advisory 
service does not include vectors away from 
conflicting traffic unless requested by the pilot. When 
advisory service is no longer desired, advise the 
controller before changing frequencies and then 
change your transponder code to 1200, if applicable. 
Pilots should also inform the controller when 
changing VFR cruising altitude. Except in programs 
where radar service is automatically terminated, the 
controller will advise the aircraft when radar is 
terminated. 

NOTE

 

Participation by VFR pilots in formal programs 
implemented at certain terminal locations constitutes pilot 
request. This also applies to participating pilots at those 
locations where arriving VFR flights are encouraged to 

Services Available to Pilots 

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