TDC reset, how do you do it?

[amurph182]

Originally Posted by odjig292

I twice tried using the TDC to calculate speed and got "not enough data". I haven't installed TM1.4 yet. Does it correct this?

you have to take at least two ranges. You identify the target, range it and send the range data to the TDC. Wait a few minutes (I usually wait 3-5) and then range it again and send the data to the TDC. THEN hit the button to calculate speed.

If you only take one range measurement or you don't send the range data to the TDC then you won't get the speed estimate.

Both were dead in the water and I circled to bring stern tubes to bear but I could not get the torpedo solution to change to finish them off. I clicked the Range and Bearing settings over and over as well as activated and deactivated the PK twice before the screen crashed.

you must be doing something wrong here. If they are dead in the water, then you just set the speed to zero and in theory you don't even need to set the AOB. Even with the PK on, when you take a new range and send it to the TDC it will update the range and bearing of the solution.

Are you not hitting the button to send the data to the TDC? Or are you not changing the speed to zero for your motionless targets?

You don't need to zero out the tdc or turn off the pk, when you have updated all of the settings the pk will simply track the target that your settings describe. If the PK is tracking a target at 1000 yards, bearing 000, AOB 90P, course 270, speed 5, and you change the AOB to 90S, the PK begins tracking a target at 1000 yards, bearing 000, course 090, speed 5. It updates those variables over time to show the motion of the target, but if you then change the range, bearing, AOB and speed it begins tracking from the last input you made.

THe only thing the PK does is show the current position of the target based upon the last entry you made. Whenever you change something it is basically the same thing as creating an entirely new solution.

Why can't I clear the previous solutions?

there are no "previous solutions." There is only one solution, and it is based off of the last information entered. The PK doesn't keep track of previous inputs, it just shows the target's position based on last input. Every data input is a new solution, and the pk tracks from that point.

What it CAN do is screw up your measurements if you don't put them in fast enough. Since it is tracking a moving target, the variables are constantly changing. If you switch to a different target and put in range, it will track a target with the same AOB and speed as the previous target but with the new range. Until you put in the correct AOB and speed for the new target it will change the range and bearing based upon the old info. Of course, once the new info is entered you can simply take a new range and it will be fine.

[amurph182]

now I have a question of my own:

when using the estimate speed function of patch 1.3, the estimate comes from your range and bearing inputs. If you enter range correctly, you get a correct course and speed estimate. I've found it to work beautifully.

I've also found that when I enter range incorrectly I get CRAZY course and speed estimates. And I would expect that, as it is only giving me an estimate based upon my inputs.

My question is how many of the previous inputs does it use when estimating course and speed? Just the last two? The last 5? All of them in the last X minutes?

The situation I'm thinking of is if I am tracking target A and decide to switch to target B, which is moving in a different direction at a different speed, and I take two range and bearing measurements will I get the correct course and speed? Or will the speed estimate be made with ALL of my inputs and thus provide me with some nutty course and speed info?

[fireship4]

I remember someone telling me that it was just the last two but dont take my word for it.

[Rockin Robbins]

I agree with Werner. Resetting the PK is definitely not necessary at all. It is VERY important, however, to enter new information in the proper order to get good targeting. This is true whether or not you reset the PK.

Let's trace the reasoning for my weird opinion, but first the gospel:

1. determine target course and speed
2. enter target speed into the TDC first
3. then enter course or AoB into TDC second
4. enter range/bearing into TDC LAST!!!

Why?

Let's do it wrong and trace the result, step by step, assuming you start tracking an original target accurately. As we begin you can see the aiming point in your attack screen superimposed on the target position, following it pretty perfectly in course and speed. Let's switch targets the wrong way.

Wrong #1: we'll take range and bearing of the new target and hit the send button.
Result: for a split second the aiming point shown in your attack screen is perfectly superimposed on your new target, but it runs away at the course and speed of the old target!

Wrong #2: we enter the speed of the new target. Result: the aiming point, which has had time to wander away from your new target is now traveling away from your new target on the old target's course, but at the new target's speed. Things are NOT getting better here.

Wrong #3: finally, we enter the course/AoB of the new target. Result: our aiming point no longer is diverging from our target. Having the correct course and speed, it merely keeps its present distance on a parallel course. Any torpedoes shot will sink that mythical hole in the water as projected on your attack screen.

Whatever order you enter the new course and speed, you MUST ENTER THE RANGE/BEARING LAST! Only then will the projected impact point be superimposed on your target. Turning the PK off and back on is completely unnecessary, and in fact will give you a false sense of security because it fixes nothing if you enter the information in the wrong order.

Why? Same thought experiment. We've reset the PK. TDC shows speed 0, AoB 0, range 0. Lets do the steps in the wrong order again.

Wrong #1. Aim at the target, get the range, hit the send bearing/range button. Result: for a split second your aiming point on the attack screen is accurate, but it has speed zero. The real target runs away from your aiming point.

Wrong #2: determine target course and either enter that directly or enter AoB. Result: nothing changes. The aiming poing is still stationary as an object with zero speed can't respond to a new course.

Wrong #3: we finally enter the speed: Result: the aiming point is on that parallel course but not coincident with the target.

Again, entering the range/bearing last is the key to manual targeting. I don't have a clue why nobody has called attention to this in the past. I hope that I have not only laid the misconceptions to rest but proven my case to everyone's satisfaction. Thanks Werner for getting me hooked on this stuff!

[brandtryan]

Yup, I had to watch Werner's videos a few times--but now I "get it", and have had some good success' as a result.

[jazman]

This is Sub(sim) School. Your homework is now to practice this stuff until you understand it enough to explain it.

[letterboy1]

Well, I just did some homework with Amurph's lesson in this thread for engaging two targets with manual TDC. Long story short, I fired 3 fish on slow speed at the front merchant when he was at AoB=0, then swung the scope to the following merchant and, after putting his identity in the TDC, I ranged him, entered new AoB and fired 3 fish at fast speed. As torpedo 4, 5, and 6 were leaving their tubes, numbers 1,2, and 3 were hitting the front ship. The second ship didn't have enough time to maneuver before all three fish hit him as well.

This thread has been most usefull. Thanks!

[jazman]

Originally Posted by letterboy1

Well, I just did some homework with Amurph's lesson in this thread for engaging two targets with manual TDC. Long story short, I fired 3 fish on slow speed at the front merchant when he was at AoB=0, then swung the scope to the following merchant and, after putting his identity in the TDC, I ranged him, entered new AoB and fired 3 fish at fast speed. As torpedo 4, 5, and 6 were leaving their tubes, numbers 1,2, and 3 were hitting the front ship. The second ship didn't have enough time to maneuver before all three fish hit him as well.

You have graduated, summa cum laude.

[Fincuan]

Originally Posted by letterboy1

...after putting his identity in the TDC, I ranged him, entered new AoB and fired 3 fish at fast speed...

It's also possible to identify all the targets beforehand, so that you only have to lock him, get the range, enter AOB and fire.

[Rockin Robbins]

Originally Posted by letterboy1

Well, I just did some homework with Amurph's lesson in this thread for engaging two targets with manual TDC. Long story short, I fired 3 fish on slow speed at the front merchant when he was at AoB=0, then swung the scope to the following merchant and, after putting his identity in the TDC, I ranged him, entered new AoB and fired 3 fish at fast speed. As torpedo 4, 5, and 6 were leaving their tubes, numbers 1,2, and 3 were hitting the front ship. The second ship didn't have enough time to maneuver before all three fish hit him as well.

This thread has been most usefull. Thanks!

Congratulations!!!! There's nothing more satisfying (except maybe a sonar-only kill) than bagging a double kill!

[Fincuan]

Originally Posted by Rockin Robbins

Congratulations!!!! There's nothing more satisfying (except maybe a sonar-only kill) than bagging a double kill!

True, but only if we are limited to SH4! The next step is a sonar-only double kill with radar-only approach It's quite exciting to look at the stopwatch and wait for the torps to hit, and then check the logbook to see what it was that you hit, since you never saw the targets.

[letterboy1]

Thanks, guys! And Fincuan, good call on that . . . I didn't think to try ID-ing the target before-hand.