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AIM 

6/17/21 

beyond the departure end of the runway and within 
300 feet of the traffic pattern altitude. 

d. 

Many towers are equipped with a tower radar 

display. The radar uses are intended to enhance the 
effectiveness and efficiency of the local control, or 
tower, position. They are not intended to provide 
radar services or benefits to pilots except as they may 
accrue through a more efficient tower operation. The 
four basic uses are: 

1.  To determine an aircraft’s exact location. 

This is accomplished by radar identifying the VFR 
aircraft through any of the techniques available to a 
radar position, such as having the aircraft 

squawk 

ident

. Once identified, the aircraft’s position and 

spatial relationship to other aircraft can be quickly 
determined, and standard instructions regarding VFR 
operation in Class B, Class C, and Class D surface 
areas will be issued. Once initial radar identification 
of a VFR aircraft has been established and the 
appropriate instructions have been issued, radar 
monitoring may be discontinued; the reason being 
that the local controller ’s primary means of 
surveillance in VFR conditions is visually scanning 
the airport and local area. 

2.  To provide radar traffic advisories. 

Radar 

traffic advisories may be provided to the extent that 
the local controller is able to monitor the radar 
display. Local control has primary control responsibi-
lities to the aircraft operating on the runways, which 
will normally supersede radar monitoring duties. 

3.  To provide a direction or suggested 

heading. 

The local controller may provide pilots 

flying VFR with generalized instructions which will 
facilitate operations; e.g., “PROCEED SOUTH-
WESTBOUND, ENTER A RIGHT DOWNWIND 
RUNWAY THREE ZERO,” or provide a suggested 
heading to establish radar identification or as an 
advisory aid to navigation; e.g., “SUGGESTED 
HEADING TWO TWO ZERO, FOR RADAR 
IDENTIFICATION.” In both cases, the instructions 
are advisory aids to the pilot flying VFR and are not 
radar vectors. 

NOTE

 

Pilots have complete discretion regarding acceptance of 
the suggested headings or directions and have sole 
responsibility for seeing and avoiding other aircraft. 

4.  To provide information and instructions to 

aircraft operating within Class B, Class C, and 

Class  D surface areas. 

In an example of this 

situation, the local controller would use the radar to 
advise a pilot on an extended downwind when to turn 
base leg. 

NOTE

 

The above tower radar applications are intended to 
augment the standard functions of the local control 
position. There is no controller requirement to maintain 
constant radar identification. In fact, such a requirement 
could compromise the local controller’s ability to visually 
scan the airport and local area to meet FAA responsibilities 
to the aircraft operating on the runways and within the 
Class B, Class C, and Class D surface areas. Normally, 
pilots will not be advised of being in radar contact since 
that continued status cannot be guaranteed and since the 
purpose of the radar identification is not to establish a link 
for the provision of radar services. 

e. 

A few of the radar equipped towers are 

authorized to use the radar to ensure separation 
between aircraft in specific situations, while still 
others may function as limited radar approach 
controls. The various radar uses are strictly a function 
of FAA operational need. The facilities may be 
indistinguishable to pilots since they are all referred 
to as tower and no publication lists the degree of radar 
use. Therefore, when in communication with a tower 
controller who may have radar available, do not 
assume that constant radar monitoring and complete 
ATC radar services are being provided

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3.  Traffic Patterns 

a. 

It is recommended that aircraft enter the airport 

traffic pattern at one of the following altitudes listed 
below. These altitudes should be maintained unless 
another traffic pattern altitude is published in the 
Chart Supplement U.S. or unless otherwise required 
by the applicable distance from cloud criteria 
(14 CFR Section 91.155). (See FIG 4

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2 and 

FIG 4

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3): 

1. 

Propeller

driven aircraft enter the traffic 

pattern at 1,000 feet above ground level (AGL). 

2. 

Large and turbine

powered aircraft enter the 

traffic pattern at an altitude of not less than 1,500 feet 
AGL or 500 feet above the established pattern 
altitude. 

3. 

Helicopters operating in the traffic pattern 

may fly a pattern similar to the fixed

wing aircraft 

pattern, but at a lower altitude (500 AGL) and closer 
to the runway. This pattern may be on the opposite 
side of the runway from fixed

wing traffic when 

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Airport Operations