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AIM 

6/17/21 

and plans to fly level for 30 seconds outbound before starting the turn back to the fix on final approach. If the winds were 
negligible at flight altitude, this procedure would bring the pilot inbound across the fix precisely at the specified time of 
12:07. However, if expecting headwind on final approach, the pilot should shorten the 30 second outbound course somewhat, 
knowing that the wind will carry the aircraft away from the fix faster while outbound and decrease the ground speed while 
returning to the fix. On the other hand, compensating for a tailwind on final approach, the pilot should lengthen the 
calculated 30 second outbound heading somewhat, knowing that the wind would tend to hold the aircraft closer to the fix 
while outbound and increase the ground speed while returning to the fix. 

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11.  Radar Approaches 

a. 

The only airborne radio equipment required for 

radar approaches is a functioning radio transmitter 
and receiver. The radar controller vectors the aircraft 
to align it with the runway centerline. The controller 
continues the vectors to keep the aircraft on course 
until the pilot can complete the approach and landing 
by visual reference to the surface. There are two types 
of radar approaches: Precision (PAR) and Surveil-
lance (ASR). 

b. 

A radar approach may be given to any aircraft 

upon request and may be offered to pilots of aircraft 
in distress or to expedite traffic, however, an ASR 
might not be approved unless there is an ATC 
operational requirement, or in an unusual or 
emergency situation. Acceptance of a PAR or ASR by 
a pilot does not waive the prescribed weather 
minimums for the airport or for the particular aircraft 
operator concerned. The decision to make a radar 
approach when the reported weather is below the 
established minimums rests with the pilot. 

c. 

PAR and ASR minimums are published on 

separate pages in the FAA Terminal Procedures 
Publication (TPP). 

1.  Precision Approach (PAR). 

A PAR is one in 

which a controller provides highly accurate naviga-
tional guidance in azimuth and elevation to a pilot. 
Pilots are given headings to fly, to direct them to, and 
keep their aircraft aligned with the extended 
centerline of the landing runway. They are told to 
anticipate glidepath interception approximately 10 to 
30 seconds before it occurs and when to start descent. 
The published Decision Height will be given only if 
the pilot requests it. If the aircraft is observed to 
deviate above or below the glidepath, the pilot is 
given the relative amount of deviation by use of terms 
“slightly” or “well” and is expected to adjust the 
aircraft’s rate of descent/ascent to return to the 
glidepath. Trend information is also issued with 
respect to the elevation of the aircraft and may be 
modified by the terms “rapidly” and “slowly”; 
e.g., “well above glidepath, coming down rapidly.” 

Range from touchdown is given at least once each 
mile. If an aircraft is observed by the controller to 
proceed outside of specified safety zone limits in 
azimuth and/or elevation and continue to operate 
outside these prescribed limits, the pilot will be 
directed to execute a missed approach or to fly a 
specified course unless the pilot has the runway 
environment (runway, approach lights, etc.) in sight. 
Navigational guidance in azimuth and elevation is 
provided the pilot until the aircraft reaches the 
published Decision Height (DH). Advisory course 
and glidepath information is furnished by the 
controller until the aircraft passes over the landing 
threshold, at which point the pilot is advised of any 
deviation from the runway centerline. Radar service 
is automatically terminated upon completion of the 
approach. 

2.  Surveillance Approach (ASR).

 An ASR is 

one in which a controller provides navigational 
guidance in azimuth only. The pilot is furnished 
headings to fly to align the aircraft with the extended 
centerline of the landing runway. Since the radar 
information used for a surveillance approach is 
considerably less precise than that used for a 
precision approach, the accuracy of the approach will 
not be as great and higher minimums will apply. 
Guidance in elevation is not possible but the pilot will 
be advised when to commence descent to the 
Minimum Descent Altitude (MDA) or, if appropriate, 
to an intermediate step

down fix Minimum Crossing 

Altitude and subsequently to the prescribed MDA. In 
addition, the pilot will be advised of the location of 
the Missed Approach Point (MAP) prescribed for the 
procedure and the aircraft’s position each mile on 
final from the runway, airport or heliport or MAP, as 
appropriate. If requested by the pilot, recommended 
altitudes will be issued at each mile, based on the 
descent gradient established for the procedure, down 
to the last mile that is at or above the MDA. Normally, 
navigational guidance will be provided until the 
aircraft reaches the MAP. Controllers will terminate 
guidance and instruct the pilot to execute a missed 
approach unless at the MAP the pilot has the runway, 

Arrival Procedures 

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