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6/17/21 

AIM 

gust front detection, storm growth and decay, 
microburst prediction, and turbulence detection. 

(c) 

TDWR also provides a geographical 

situation display (GSD) for supervisors and traffic 
management specialists for planning purposes. The 
GSD displays (in color) 6 levels of weather 
(precipitation), gust fronts and predicted storm 
movement(s). This data is used by the tower 
supervisor(s), traffic management specialists and 
controllers to plan for runway changes and 
arrival/departure route changes in order to both 
reduce aircraft delays and increase airport capacity. 

4.  Weather System Processor (WSP). 

(a) 

The WSP provides the controller, supervi-

sor, traffic management specialist, and ultimately the 
pilot, with the same products as the terminal doppler 
weather radar (TDWR) at a fraction of the cost of a 
TDWR. This is accomplished by utilizing new 
technologies to access the weather channel capabili-
ties of the existing ASR

9 radar located on or near the 

airport, thus eliminating the requirements for a 
separate radar location, land acquisition, support 
facilities and the associated communication landlines 
and expenses. 

(b) 

The WSP utilizes the same RBDT display 

as the TDWR and LLWAS, and, just like TDWR, also 
has a GSD for planning purposes by supervisors, 
traffic management specialists and controllers. The 
WSP GSD emulates the TDWR display, i.e., it also 
depicts 6 levels of precipitation, gust fronts and 
predicted storm movement, and like the TDWR GSD, 
is used to plan for runway changes and arrival/depar-
ture route changes in order to reduce aircraft delays 
and to increase airport capacity. 

(c) 

This system is currently under develop-

ment and is operating in a developmental test status 
at the Albuquerque, New Mexico, airport. When 
fielded, the WSP is expected to be installed at 

34 airports across the nation, substantially increasing 
the safety of the American flying public. 

5.  Operational aspects of LLWAS, TDWR 

and WSP. 

To demonstrate how this data is used by both the 
controller and the pilot, 3 ribbon display examples 
and their explanations are presented: 

(a)  MICROBURST ALERTS 

EXAMPLE

 

This is what the controller sees on his/her ribbon display 
in the tower cab. 

27A MBA 35K

 2MF 250 20 

NOTE

 

(See FIG 7

1

17 to see how the TDWR/WSP determines 

the microburst location). 

This is what the controller will say when issuing the 
alert. 

PHRASEOLOGY

 

RUNWAY 27 ARRIVAL, MICROBURST ALERT, 35 KT 
LOSS 2 MILE FINAL, THRESHOLD WIND 250 AT 20. 

In plain language, the controller is telling the pilot 
that on approach to runway 27, there is a microburst 
alert on the approach lane to the runway, and to 
anticipate or expect a 35 knot loss of airspeed at 
approximately 2 miles out on final approach (where 
it will first encounter the phenomena). With that 
information, the aircrew is forewarned, and should be 
prepared to apply wind shear/microburst escape 
procedures should they decide to continue the 
approach. Additionally, the surface winds at the 
airport for landing runway 27 are reported as 
250 degrees at 20 knots. 

NOTE

 

Threshold wind is at pilot’s request or as deemed 
appropriate by the controller. 

REFERENCE

 

FAA Order JO 7110.65, Paragraph 3

1

8b2(a), Air Traffic Control, Low 

Level Wind Shear/Microburst Advisories 

Meteorology 

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