Help with determining target angles

[Kumando]

For me the best way to determine AoB is with the AoB wheel, once you have the target speed and course the wheel do the rest, thats what i use.

[Heibges]

If you approach your target on a perpendicular course, there is a defined relationship between AOB and Bearing.

Target Moving Left to Right:
Bearing 315° = AOB 45°stb
Bearing 340° = AOB 70°sbt
Bearing 350° = AOB 80°stb
Bearing 000° = AOB 90°stb

Target Moving Right ot Left:
Bearing 45° = AOB 45°pt
Bearing 20° = AOB 70°pt
Bearing 10° = AOB 80°pt
Bearing 000° = AOB 90°pt

Angle on the Bow is a comparison in degrees between your course and the target's course. You draw a line from your ship to the target ship; then a line from the target ship out along the line of it's course. The resulting angle is Angle on the Bow. Also note that AOB is either Port (red) or Starboard (green) which refers to the direction that the target is crossing your bow, or another words, which side of the target you're looking at.

A good firing position is ahead of the target and 500 - 100 meters off the target's course which would result in an angle on the Bow of approximately 45 - 60 degrees.

The problem with accurate measurement and application of Angle on the Bow is that it's constantly changing. The remedy is to determine the Angle on the Bow of the course intercept point which is constant. Using the angle tool, draw a line along your course (zero bearing) until it reaches the target's course; then a line out along the targets course. The resulting angle is the Angle on the Bow at course intercept. Go to the periscope or UZO view and set the scope or UZO at the zero bearing. With a clean notepad, enter the course intercept angle into the TDC as Angle on the Bow. Make sure you do all the clicking of the checkmarks to enter into the TDC. Now you can rotate the scope or UZO to the moving target and the TDC will automatically update the correct Angle on the Bow. Don't change it!

You now will have amazing results with only the manual input of the correct estimated target speed.

[Heibges]

Originally Posted by von Zelda

The problem with accurate measurement and application of Angle on the Bow is that it's constantly changing. The remedy is to determine the Angle on the Bow of the course intercept point which is constant.

You now will have amazing results with only the manual input of the correct estimated target speed.

So True. Without a preplanned Firing Point, I don't know how some of these folks who say they use Manual TDC hit anything.

Speed is by far the trickiest piece of firing data to get. Especially if you are trying to get it while submerged.

[raduz]

Originally Posted by Heibges

Speed is by far the trickiest piece of firing data to get. Especially if you are trying to get it while submerged.

Getting targets speed while submerged is not too tricky. IMHO the most trickiest part of TMA is to estimate correctly the range to target, especially if it is far.

[Corsair]

Originally Posted by raduz

Getting targets speed while submerged is not too tricky. IMHO the most trickiest part of TMA is to estimate correctly the range to target, especially if it is far.

If you have the other numbers right, exact range is not so important...

[raduz]

Originally Posted by Corsair

If you have the other numbers right, exact range is not so important...

It is not important, thats correct, if you already have the targets course or you can see him. But when calculating the contacts course submerged and without Watch Officer assistance, the range to contact estimation is much trickier then getting speed.