Some slight AOB confusion.

[Tsaar]

http://img145.imageshack.us/img145/2407/shiv.png

In the first situation I am inclined to put the AOB at 0 degrees. The only problem with this is my torpedoes just shoot straight ahead.

So basically I am treating it like the second situation except I put it at 90 degrees with a speed of zero (and I still usually miss).

In all AOB calculations I see on the web it seems to have the sub perpendicular to the targets path. I seem to find my self running parallel with the ship quite often.

For me I have been treating the target as a straight line with a point in the middle, and then treating myself as a point and calculating the angle. But this doesn't take into consideration the bearing of my sub (and torpedoes obviously come straight out of the front or back).

Am I doing it wrong, and need to make 100% sure I always attack from a perpendicular angle to the target's course?

[razark]

Welcome aboard!

In the first situation I am inclined to put the AOB at 0 degrees. The only problem with this is my torpedoes just shoot straight ahead.
The first case illustrated is an AoB of 0 degrees, bearing 270. The second case is an AoB of 90 degrees starboard, bearing 270. You say the torpedo is going straight ahead. This makes me wonder if you are entering the bearing to the target.

So basically I am treating it like the second situation except I put it at 90 degrees with a speed of zero (and I still usually miss).
The torpedo leaves your sub some distance away from your periscope. It then runs straight for a short time, and then turns to its final heading. Depending on the range of the target, it can take a considerably different heading than your line of sight. This is fine; if you have the range, speed, and AoB correctly entered, the TDC will put the torpedo on a course that intersects the target's course at the same time the target gets there.

Setting the speed to zero will cause this calculation to be incorrect, resulting in a miss.

In all AOB calculations I see on the web it seems to have the sub perpendicular to the targets path. I seem to find my self running parallel with the ship quite often.
You should try to get your boat pointing away from or towards the target. The closer the torpedo's course is to your boat's course, the less room for error. You don't need to be at a 90 degree angle to the target course, and that can be bad early in the war, as the impact detonator will very often fail on a 90 degree shot. Try a 45 degree angle to the target track. Pointing your boat at the target also reduces the difference in line of sight to the target and the torpedo's actual course.

For me I have been treating the target as a straight line with a point in the middle, and then treating myself as a point and calculating the angle. But this doesn't take into consideration the bearing of my sub (and torpedoes obviously come straight out of the front or back).
Sounds a reasonable way as any to figure AoB. As long as you get good numbers, the TDC should calculate the correct torpedo gyro angle.

Am I doing it wrong, and need to make 100% sure I always attack from a perpendicular angle to the target's course?
Not always, but the closer you can get to firing the torpedo straight, the better it should be. Keep practicing, and I'm sure someone else will drop by to give you some more advice.

[Gerald]

:salute: and you have received good advice!

[Tsaar]

Welcome aboard!
This makes me wonder if you are entering the bearing to the target.


First, thanks for the great reply!

This is exactly the missing piece I was wondering about. Notice how I mentioned I felt my heading should be taken into consideration; I knew something had to be missing from what I was doing because AOB wouldnt make since unless I was perpendicular to their course.

Now for the stupid question....heh....how do you enter their bearing?

I lock on, click PK, then choose ship, then get range, then change the AOB, and then guesstimate their speed.

I haven't seen a way to enter the bearing (obviously I can see their bearing easily through the periscope when I am locked on).

[razark]

Now for the stupid question....heh....how do you enter their bearing?

I lock on, click PK, then choose ship, then get range, then change the AOB, and then guesstimate their speed.

I haven't seen a way to enter the bearing (obviously I can see their bearing easily through the periscope when I am locked on).
Entering the bearing is done at the same time you enter the range. Clicking to send range also sends the current periscope bearing. Why the torpedo is heading straight ahead is odd.

For speed, you can take two bearing/range readings with a bit of time between them. Then go to the speed entry tool, click the stopwatch, and the crew will figure the course and speed of the target for you. You can use their response to enter speed and AoB. (It's also a good sanity check. If you use the tool to calculate the speed of a cargo ship, and you find out he's doing 30 knots, you got something wrong.)


If you haven't read them yet, I'd suggest going through the Sub Skipper's Bag of Tricks (http://www.subsim.com/radioroom/showthread.php?t=146795) and Technical Help & Questions, Guides and Trainings (http://www.subsim.com/radioroom/showthread.php?t=107783) threads. I'd also recommend starting out manual targeting with one of these methods (http://www.subsim.com/radioroom/showpost.php?p=1007637&postcount=204). It's what got me started, and they're pretty easy to pick up. Once you get those working, you can move on to other methods.

[I'm goin' down]

Razark has it exactly right. When you have to time to figure it out how to use it, look at gutted's terrific Solution Solver program. It allows you to view the target as if you were in your boat looking at it through the scope after you input target course and bearing --for any configuration of your boat and the target. Seeing is believing. It confirms Razark's answers. And if you plug in target speed, it will calculate the lead angle for a torpedo shot.

Assuming the target's in the hypos are proceeding on their indicated courses (0 degrees in hypo no. 1 and 270 degrees in hypo no. 2), here are firing solutions per the Solution Solver:

Hypo no. 1. Assume target speed of 10 kts and 46 kt. speed torpedo. Firing bearings: Forward tubes - 347.3 degrees. Aft tubes - 192.3 degrees.

Hypo no. 2. Assume target speed of 10 kts and 46 kt. speed torpedo. Firing bearings: Forward tubes - 0.0 degrees. Aft tubes - 180.0 degrees.

Input the data to the TDC. Sine the target is moving, input Range on the Stadimeter. Turn on the PK. You have the target's speed (10 kts., it course, and it range). The TDC will calculate the gyro angle for the torpedoes. Viola! Antoher one bites the dust, assuming your torpedoes do not run too deep or are duds.

[I'm goin' down]

First, thanks for the great reply!

This is exactly the missing piece I was wondering about. Notice how I mentioned I felt my heading should be taken into consideration; I knew something had to be missing from what I was doing because AOB wouldnt make since unless I was perpendicular to their course.

Now for the stupid question....heh....how do you enter their bearing?

I lock on, click PK, then choose ship, then get range, then change the AOB, and then guesstimate their speed.

I haven't seen a way to enter the bearing (obviously I can see their bearing easily through the periscope when I am locked on).

I think you are realy asking how to input the target's heading (i.e. course) and not the target's bearing. To get the target's bearing, merely find it your periscope. If you see it at 10 degrees, its bearing is 10 degrees. You can use the "L" key to lock the periscope on the target, and that will provide you with its bearing. Its bearing is its perspective from your boat, with 0 degrees being the bow of your boat for bearing purposes. To get the target's heading (course) is a different matter altogether, as a target at a bearing of 10 degrees could be going (i.e. heading) in any number if directions. A target's course is its direction on a world map, and does not mean the same thing as its bearing unless by coincidence they are identical.

You need to input the heading (course) of the target to the TDC if you are going to use manual targeting. You need to plot the course of the target to set up a shot using the O'Kane or Cromwell methods, but are not required to input the target's course to the TDC and activate the Position Keeper (i.e. the PK) when using these methods. If you are manual targeting, the speed, course and range must be input into the TDC. To input course, it is strongly recommended that you activate the easy Aob mod. You use the Aob dial (periscope screen, upper right) to point the ship in the right direction (are you viewing the target's port or starboard side?), and compare it with the ship's dials on the TDC screen (periscope screen upper left), which will rotate accordingly per the Easy Aob mod) until you stop it on the target's course (heading.)

How do you find a target's course? Easy, once you have the technique down. To determine a target's course, you have to use the compass tool which you will find above the ruler on the Nav Map. Read the bottom of the compass to get its heading. (i.e. a ship heading to the north pole on the Nav Map is heading 180 degrees, even though the bow of the ship is aimed at a bearing of 0 degrees.) There are posts on how to read a compass to take a heading if this causes you some confusion. You can enter the target's course (say it is 50 degrees) by rotating the Aob dial on the upper right until the ship's dial on the upper left is at 50 degrees. Assuming you have input the target's speed, you can turn on the PK and track the target. You still have to input the range to the target using the stadimeter (periscope screen, upper right), and you may have to adjust the course on the TDC when you do, but you are getting close to having an accurate firing solution using the TDC. This is manual targeting.

Target speed - don't guess. Use the 3 minute rule. Plot the ship on the Nav Map with an "X". Start the stop watch and plot the ship with another "X" after 3 minutes. If the ship travels 10,000 yds., its speed is 10 kts., etc. You can extend the course out and read its heading (course) with your trusty compass tool, and then input it to the TDC using the ship's dials as explained above.

Manual targeting is advanced. Don't get ahead of yourself. Read the tutorials and study the video lessons in the Skippers Bag of Tricks thread. Download and activate Rockin Robbins' practice mission tutorial mod for the Dick O'Kane technique, and you can practice against a big fat tanker in the calm waters of southern California until you get proficient. It is a good way to brush up on your skills, so when you are on the line you won't get confused and miss dinner. Manual targeting should be one of the last techniques you master, as other techniques will take you less time to learn, and you can sink ships with all of them. Also, the tutorial saves you the frustration and grief of being sunk by a destroyer in the game, and you can replay it as many times as you need to.

[Tsaar]

I think you are realy asking how to input the target's heading (i.e. course) and not the target's bearing. To get the target's bearing, merely find it your periscope.

Sorry, for my poorly worded reply earlier, but I wasn't confused about terminology, I was confused about how the TDC knew where the enemy ship was relative to mine (bearing).

I realized what I had been doing wrong. I always did the range finder once, and usually didn't do it again. This wouldn't have been that big of a deal except sometimes I made adjustments to my course, and I wasn't aware the range finder also sent the target bearing to the TDC.

Last night I actually sunk a ship from 4200 yards (9k tons large passenger carrier...got lucky because I only hit it once haha). I ran into the living room and excitedly told my wife...who looked at me like I was insane.

[I'm goin' down]

your wife appears to be an excellent judge of character! :D:D

[magic452]

"I ran into the living room and excitedly told my wife...who looked at me like I was insane. "

Don't worry she will get use to it in a very short time. :haha:

Manual targeting takes some patients and practice but you will get the hang of it soon.

Magic