4 Bearing method, useless in combat?

[maillemaker]

In bad weather I have made pursuits by hydrophone - dive to periscope depth and use hydrophone to get a bearing, then surface and drive hard for 10-20 minutes and then dive and listen, repeat until you get a visual. Usually you can stalk around them at extreme visual distance without getting caught. This is risky once they start carrying guns because at 1000 meters they will tear you up.

My attack approaches are relatively simple. I believe there was a historical uboat captain who did similar 90 degree attacks almost exclusively.

The first thing is to make visual contact with the target(s). Your Watch Officer will be able to provide you with an exact range and bearing, unless you have installed a mod to reduce the range accuracy. Plot this point on your navigation map.

Next you will have to eyeball the target to estimate the Angle on the Bow, and thus the target heading. Draw a line on your map from the point of the target along its estimated heading.

Now you have to drive your boat to an intercept position such that you will be 90 degrees to the target when it passes in front of you. If you are at extreme range (10,000 meters or more) and there are no escorts with radar you can drive your intercept on the surface. You may have to drive away from the contact and do an "end around" maneuver to get ahead of them.

Once you are ahead of your target and are driving your boat on a course perpendicular (90 degrees) to the target, drive until you regain visual contact. Dive before you are spotted or the target will start zig-zagging making your job more difficult.

Proceed submerged until you are within 1000 meters of the target course. You will need to make periscope observations frequently to make sure you are on the correct course and that you are closing with the target fast enough to make the shot. Ideally you want to be within 1000 meters when you fire - I prefer 700-500 meters ideally especially for lone targets.

While you are waiting for the target to cross your bow, go to your TDC screen (F6) and turn on the TDC. You'll set up for a 90 degree shot. It's easy.

Set the Angle on the Bow to 90 degrees starboard or port. Remember, this is from the target's perspective. If you are on the starboard (right) side of the target, then you want to set the AoB to 90 degrees starboard.

Next dial up the target speed. You can infer the target speed by watching it carefully and by noting the size of the bow wake. Like I said, I usually guess 7 knots. It is possible to do a "fixed wire" method of timing how long it takes the ship to travel from stem to stern across your non-moving periscope vertical reticule, but to do this you need a positive ID of the ship from the ID book to determine the ship's length. With GWX gold there are so many ships by the time you thumbed through the whole book and found it the war would be over. However, if you know the ship's length, and you can time how long it takes it to travel past your reticule, you can get a fairly accurate speed using this formula:

speed in knots = length in meters / time in seconds * 1.94

In order to get an accurate time either your sub needs to be stopped or you need to be driving directly at it making your speed irrelevant.

With map contacts on it is trivial to place a mark on the target on the map, wait 3:15 seconds, then make another mark and draw a line beween the marks. That gives you the speed in knots.

Like I said, I find it easier to estimate speed now.

So, input the speed into the TDC.

Center your scope on 0 degrees, and toggle the TDC. Now move your scope towards the target. At about 5-10 degrees from zero (depending on the speed of your torpedo setting) the gyroangle will hit zero. This is where you need to aim your periscope regardless of distance to target. That is the nice thing about the 90 degree shot - distance to target is irrelevant. There is no need to set the distance in the TDC unless you want semi-accurate stopwatch time-to-target estimations. Since I usually shoot at 500-1000 meters I leave it at the default 500 meters. If something doesn't go boom shortly after the stopwatch passes the red line it's time to consider what you are going to do next.

Now you just wait for the ship to cross your reticule. When it does, fire your eels. Make sure you have opened your outer doors prior to firing or your firing will be delayed, which is bad. Assuming you estimated the speed properly, your torpedoes will hit.

It's important to remember to toggle the TDC and make sure that the gyroangle is tracking your periscope movements. I have screwed up more than one torpedo launch by failing to toggle the TDC inputs off and as a result your torpedo goes sailing off in the wrong direction.

You know you've got it when moving the scope makes a ticking sound. No ticking sound and your TDC is not set properly.

Convoy attack is the same, but the approach is more difficult because of escorts.

Steve

[Aktungbby]

Barker262!

[flag4]

Originally Posted by maillemaker

In bad weather I have made pursuits by hydrophone - dive to periscope depth and use hydrophone to get a bearing, then surface and drive hard for 10-20 minutes and then dive and listen, repeat until you get a visual. Usually you can stalk around them at extreme visual distance without getting caught. This is risky once they start carrying guns because at 1000 meters they will tear you up.

My attack approaches are relatively simple. I believe there was a historical uboat captain who did similar 90 degree attacks almost exclusively.

The first thing is to make visual contact with the target(s). Your Watch Officer will be able to provide you with an exact range and bearing, unless you have installed a mod to reduce the range accuracy. Plot this point on your navigation map.

Next you will have to eyeball the target to estimate the Angle on the Bow, and thus the target heading. Draw a line on your map from the point of the target along its estimated heading.

Now you have to drive your boat to an intercept position such that you will be 90 degrees to the target when it passes in front of you. If you are at extreme range (10,000 meters or more) and there are no escorts with radar you can drive your intercept on the surface. You may have to drive away from the contact and do an "end around" maneuver to get ahead of them.

Once you are ahead of your target and are driving your boat on a course perpendicular (90 degrees) to the target, drive until you regain visual contact. Dive before you are spotted or the target will start zig-zagging making your job more difficult.

Proceed submerged until you are within 1000 meters of the target course. You will need to make periscope observations frequently to make sure you are on the correct course and that you are closing with the target fast enough to make the shot. Ideally you want to be within 1000 meters when you fire - I prefer 700-500 meters ideally especially for lone targets.

While you are waiting for the target to cross your bow, go to your TDC screen (F6) and turn on the TDC. You'll set up for a 90 degree shot. It's easy.

Set the Angle on the Bow to 90 degrees starboard or port. Remember, this is from the target's perspective. If you are on the starboard (right) side of the target, then you want to set the AoB to 90 degrees starboard.

Next dial up the target speed. You can infer the target speed by watching it carefully and by noting the size of the bow wake. Like I said, I usually guess 7 knots. It is possible to do a "fixed wire" method of timing how long it takes the ship to travel from stem to stern across your non-moving periscope vertical reticule, but to do this you need a positive ID of the ship from the ID book to determine the ship's length. With GWX gold there are so many ships by the time you thumbed through the whole book and found it the war would be over. However, if you know the ship's length, and you can time how long it takes it to travel past your reticule, you can get a fairly accurate speed using this formula:

speed in knots = length in meters / time in seconds * 1.94

In order to get an accurate time either your sub needs to be stopped or you need to be driving directly at it making your speed irrelevant.

With map contacts on it is trivial to place a mark on the target on the map, wait 3:15 seconds, then make another mark and draw a line beween the marks. That gives you the speed in knots.

Like I said, I find it easier to estimate speed now.

So, input the speed into the TDC.

Center your scope on 0 degrees, and toggle the TDC. Now move your scope towards the target. At about 5-10 degrees from zero (depending on the speed of your torpedo setting) the gyroangle will hit zero. This is where you need to aim your periscope regardless of distance to target. That is the nice thing about the 90 degree shot - distance to target is irrelevant. There is no need to set the distance in the TDC unless you want semi-accurate stopwatch time-to-target estimations. Since I usually shoot at 500-1000 meters I leave it at the default 500 meters. If something doesn't go boom shortly after the stopwatch passes the red line it's time to consider what you are going to do next.

Now you just wait for the ship to cross your reticule. When it does, fire your eels. Make sure you have opened your outer doors prior to firing or your firing will be delayed, which is bad. Assuming you estimated the speed properly, your torpedoes will hit.

It's important to remember to toggle the TDC and make sure that the gyroangle is tracking your periscope movements. I have screwed up more than one torpedo launch by failing to toggle the TDC inputs off and as a result your torpedo goes sailing off in the wrong direction.

You know you've got it when moving the scope makes a ticking sound. No ticking sound and your TDC is not set properly.

Convoy attack is the same, but the approach is more difficult because of escorts.

Steve

cheers - that's great. I'm printing it off...its all a bit 'drop and run' I like that. has a rough feel to it - a real feel too.