[I'm goin' down]

copies from a post in another thread that I wrote.

Here is the easiest ways to get started. Line up at 90 degrees to target's course. If the target is, say, at 70 degrees to your starboard (to your right) and is moving from right to left, its Aob is 20 degrees. (It is important that you understand this concept: bearing (70 degrees) + Aob (20 degrees) = 90 degree angle.) With the TDC light in the off position, set the Aob to 20 degree left (not right!), as the Aob from view from the target's bow is on the left side. Activate the TDC (i.e. turn on the light). Lock on the target if you want and the Aob dial will move as the target closes on a 90 degree Aob. Fire when ready (i.e. say, fire when the target is at a bearing of 10 degrees (bearing (10 degrees) + Aob (80 degrees = 90 degree angle)) to be consistent with the O'Kane method; however, since the TDC is tracking the target you are not confined to firiing at that bearing.

Here is the copy of one of my posts in the ATO forum that should help you understand the counter intutive Aob dial setting in ATO. This is where i made the conceptual breakthrough. Short version -I was setting the Aob in the exact opposite direction. You may need to think about this. Try to visualize it. This example is related to firing when the target's Aob is 90 degrees, as in an O'Kane attack or fast 90.

"The left side of the Aob dial on your U-Boat says, "Bug Links." Translated this means bow of the ship left. When a target is approaching the bow of you your ship from starboard (i.e. it is moving from right to left) [as in my example above], the Aob viewed from the target's bow is to its left (port). This means that the Aob dial on the UBoat, as viewed from the bow of the target, should be set to 90 degrees Bug Links (bow left.)

The right side of the Aob dial says, "Bug Recht." Translated this means bow of the ship right. When a target is approaching the bow of you your ship from the port (i.e. it is moving from left to right), the Aob viewed from the target's bow is to its right (starboard.) This means that the Aob dial on the UBoat, as viewed from the bow of the target, should be set to 90 degrees Bug Recht (bow right.)

For a captain such as myself who learned on an American sub this is counter intuitive. However, it now makes sense, plus it worked. I sank the submarine in the tutorial with four shots, all hits. The Aob was set at 90 degrees Bug Links (bow left) when the target crossed the wire at 10 degrees heading right to left at 7.5 kts.

Bottom line, once you have the target's Aob, input it in the TDC with scope locked on the target. With the TDC activated the Aob dial will move in relation to movements of the scope. For an O'Kane shot, when the Aob is either 10 degrees or 350 degrees, depending on the target's heading, fire the torpedoes.

Kiub-- the "dial" used to calculate the target's range, speed and Aob. Kiub means Kreigsmarine Interface for U Boats. Read Karamazovnew's tiutorial. It is somewhat difficult to follow, but if you practice, you will figure out how to use it. Now, get your ass back on the line and sink some ships.
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