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FIG 7−1−15

LLWAS Siting Criteria

(c) The early detection of a wind shear/mi-

cro−burst event, and the subsequent warning(s)

issued to an aircraft on approach or departure, will

alert the pilot/crew to the potential of, and to be

prepared for, a situation that could become very

dangerous! Without these warnings, the aircraft may

NOT be able to climb out of, or safely transition, the

event, resulting in a catastrophe. The air carriers,

working with the FAA, have developed specialized

training programs using their simulators to train and

prepare their pilots on the demanding aircraft

procedures required to escape these very dangerous

wind shear and/or microburst encounters.

2. Low Level Wind Shear Alert System


(a) The LLWAS provides wind data and

software processes to detect the presence of

hazardous wind shear and microbursts in the vicinity

of an airport. Wind sensors, mounted on poles

sometimes as high as 150 feet, are (ideally) located

2,000 − 3,500 feet, but not more than 5,000 feet, from

the centerline of the runway. (See FIG 7−1−15.)