Vaisala CT25K, Руководство пользователя

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To monitor windshear alerts:
1. Look for the windshear alert on the LLWAS screen. Depending on the system
configuration, the alert is indicated by one or all of the following:
• The letters MBA or WSA in the LLWAS screen
• A red frame in the LLWAS screen
• A beeping alarm sound (option)
2. In the LLWAS screen, note the estimated location of the first encounter with the
windshear conditions and the estimated headwind loss or gain, and report the alert
according to the airport-specific practices.
When the LLWAS processing status is SUPPORT , the system cannot
produce windshear and microburst alerts. Therefore, windshear conditions might
exist even if there is no alert on the screen. This might be caused by a system restart
or a problem in the system. Contact system maintenance immediately.
CAUTION!
In cases where there are multiple windshear condition situations, the cases are
arbitrated and only the most hazardous alert for that runway is issued. The arbitration
order is the following:
a. Microburst
b. Windshear with large loss
c. Windshear with large gain
d. Windshear with small loss
e. Windshear with small gain
In these cases the location reported is the location of the first encounter with any of
these phenomena.
When the windshear conditions are at the runway area, there will be
both headwind gains and losses for the same touchdown direction. For example,
the runway may first encounter headwind gains at the touchdown, but headwind
loss thereafter. The headwind loss is issued as an alert because loss is more
important.
CAUTION!
The following table presents examples of typical LLWAS screen texts.
Table 14 WeatherView: Sample LLWAS Screen Texts
LLWAS Screen Text Explanation
CF 000 00 14:52:03 CF
Centerfield.
000
Wind direction in degrees.
00
Wind speed in preconfigured units, normally an
instant value. The maximum value shown is 99.
14:52:03
Time of the data report, in this case 2:52 p.m. and
3 seconds.
Chapter 4 – WeatherView
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