very nice video Nefelodamon ! bravo !
you don't need to draw the 20km radius circle at all ! only the four lines for the bearing and no matter how long they will be
i suggest to get the pato's image (the one that have circles till 4.650m radius--here:
fixes+new 'one degree bearing') and directly place the bearing lines to the bearings that are given from sonarman (it will make your life ...easier)
also for the last report of sonarman (the one that will give you the 'hot' 'fifth' bearing line is no need to come to a dead stop .when you get the report from sonarman...pause the game and draw the line to the given bearing
also,once you get the direction of the target and you want to turn your boat to a 90degrees angle course ,simply add (or minus--depends from if you have the target from your left or right of you) 90 to targets course and set your boat to this direction
and something for last , when you use the tdc and want to set the 90 aob ,be sure that your periscope is pointed to 0 degrees.anytime you will use the tdc ,always be sure first that the peri is pointing to 0 degrees (all this in case that your course is setted to a 90 degrees angle with target's course)
you made a great video !
bye