BendixKing KMD 150 - Pilots Guide - Manual (Page 130)

The WX-500 detects electrical discharges and sends them to the KMD
150 as storm cells or as independent strikes. The following examples
include the KMD 150's Stormscope
® screens in both the cell display
mode and the strike display mode. When in map mode, if enabled, the
cells and strikes will be displayed as lightning icons. To make a more
detailed analysis of the storm, switch back to the dedicated
Stormscope
® screen.
RADIAL SPREAD
When the KMD 150 is in the strike display mode, it is common for a trian-
gular-shaped stream of discharge points to appear between the aircraft
symbol on the Stormscope
® screen and a cluster of discharge points
within the range of the WX-500. A similar stream of discharge points
may appear radiating away from the aircraft symbol in the direction of
possible thunderstorm activity beyond the range of the WX-500. These
phenomena are examples of radial spread. Discharge points in radial
spread do not necessarily indicate the exact location of atmospheric
electrical discharges. To counteract radial spread, L3 Communciations
applied its extensive research in lightning detection to develop enhanced
lightning positioning algorithms. These algorithms (used only in the cell
display mode) greatly reduce radial spread and improve the depiction of
thunderstorms on the display. The strike display mode does not use the
enhanced lightning positioning algorithms; instead, it uses technology
similar to that found in older Stormscope
® systems and in competitor
lightning detection systems.
TYPICAL PATTERNS
Three Clusters within the 200 nm Range Ring
Figure 13-5 shows the Stormscope
®
screen in the 360° weather view at
the 200 nm range. Using this knowledge, the outer range ring, and the
azimuth markers, the three clusters of discharge points on the left-hand
Stormscope
® screen (cell display mode) can be interpreted as repre-
senting three thunderstorm cells at the following azimuth and range:
Cluster Azimuth (clock position) Range
1 11:00 180 nm
2 4:00 75 nm
3 4:00 180 nm
Analysis of the right-hand Stormscope ® screen (strike display mode)
yields a similar, but less certain interpretation due to radial spread.
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Rev 3 Aug/2004 KMD 150 Pilot's Guide
Stormscope ® Operation