FLIR RAYMARINE A75 WiFi - Drift Effects on Sector Search Patterns; Creating an Expanding Square Search Pattern

3. Select the Commence Search Point box.
4. Enter the latitude and longitude for the starting
point of the search pattern.
By default and after a power cycle the coordinates
shall be set to zeros. If you have already created
a search pattern then the last used Commence
Search Point (CSP) position is displayed.
5. Enter the reported/observed drift Direction and
Speed in the relevant boxes.
6. Select the Search Speed box and enter your
search speed.
Search Speed is the Speed Through the Water
(STW).
7. Select the Leg Time box and enter the amount of
time that each leg should take.
The Track Spacing is automatically calculated
from the specied Search Speed and Leg Time.
8. Select New Search Offset the ‘-’ or ‘+’ buttons to
offset the bearing to the rst waypoint.
The rst waypoint after the CSP waypoint will
always be towards the specied drift direction,
this can be adjusted by applying an Offset.
9. Double check your settings.
10.Select Create Pattern.
The Pattern will now be created as a Route ready
for you to follow.
Drift effects on Sector Search patterns
As the search patterns account for drift the resulting
Route may not resemble the pattern shown above.
Example Drift
Direction: 0°
Speed: 0 Kts
Direction: 45°
Speed: 0 Kts
Example Drift
Direction: 0°
Speed: 0.5 Kts
Direction: 0°
Speed: 1 Kts
Creating an Expanding Square search
pattern
The Expanding Square search pattern is outwards
spiralling square pattern.
Note: As the Search patterns take in to account
drift, the resulting Route may not resemble the
patterns shown.
To create an Expanding Square search pattern follow
the steps below:
1. Select Search Patterns from the Navigate menu:
(Menu > Navigate > Search Patterns).
2. Select Expanding Square.
3. Select the Commence Search Point box.
4. Enter the latitude and longitude for the center
starting point for the search pattern.
By default and after a power cycle the coordinates
shall be set to zeros. If you have already created
a search pattern then the last used Commence
Search Point (CSP) position is displayed.
5. Enter the reported tidal drift Direction and Speed
in the relevant boxes.
6. Select the Search Speed box and enter your
search speed.
Search Speed is the Speed Through the Water
(STW).
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