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reignofdeath
12-17-12, 03:36 PM
Okay, so here I am sailing merily along. When boom, a map contact shows up. Alright, cool. I click on it, and it shows 3 bearings, scope bearing, true bearing and just bearing.. sometimes they can be the same, sometimes not. But which one is its Course?? Course is blank but sometimes it is filled with cardinal directions.. Its so confusing sometimes. Im used to GWX, NW at medium speed.

gap
12-17-12, 06:34 PM
Okay, so here I am sailing merily along. When boom, a map contact shows up. Alright, cool. I click on it, and it shows 3 bearings, scope bearing, true bearing and just bearing.. sometimes they can be the same, sometimes not. But which one is its Course?? Course is blank but sometimes it is filled with cardinal directions.. Its so confusing sometimes. Im used to GWX, NW at medium speed.

dunno about "just bearing", but "scope bearing" is the bearing to the target relative to our position and heading. It is plotted putting our sub at the center of the compass rose and facing N. "True bearing" is the same, but unrespective of sub heading. The two are equal when our heading is 00. In any other case you can convert scope bearings into true bearings by subtracting your current heading from scope bearing and viceversa. If for example you are heading E (90°), and scope bearing to target is 45°, the true bearing is 45° - 90° = -45° = 315°.

Notice that the sonarman is always reporting scope bearings that you should convert into true bearing for not getting confused (I don't remember about watchcrew and radar repors though).

As for target courses of BdU contact reports, when they are known, they can be given either as exact compass angles or as extimated compass rose quadrants: i.e. N (348.75° to 11.25°), NNE (11.25° to 33.75°), NE (33.75° to 56.25°), etc. If a remember correctly, there is an option in TDW's UI for switching between the two notations :up:

reignofdeath
12-18-12, 05:00 AM
dunno about "just bearing", but "scope bearing" is the bearing to the target relative to our position and heading. It is plotted putting our sub at the center of the compass rose and facing N. "True bearing" is the same, but unrespective of sub heading. The two are equal when our heading is 00. In any other case you can convert scope bearings into true bearings by subtracting your current heading from scope bearing and viceversa. If for example you are heading E (90°), and scope bearing to target is 45°, the true bearing is 45° - 90° = -45° = 315°.

Notice that the sonarman is always reporting scope bearings that you should convert into true bearing for not getting confused (I don't remember about watchcrew and radar repors though).

As for target courses of BdU contact reports, when they are known, they can be given either as exact compass angles or as extimated compass rose quadrants: i.e. N (348.75° to 11.25°), NNE (11.25° to 33.75°), NE (33.75° to 56.25°), etc. If a remember correctly, there is an option in TDW's UI for switching between the two notations :up:

Two words.

Thank. and You. :up:

gap
12-18-12, 06:16 AM
Two words.

Thank. and You. :up:

My pleasure :salute: