Yet another TDC question - what do these show?

panthercules · 04-13-07, 01:14 AM

Ok - I obviously do not have the hang of this US TDC. I've watched the Neal video (very cool) and read several TDC-related threads, but I still don't really understand exactly how this thing is supposed to work (even when it's not having it's bug with targets on the "wrong" side).

I understand how to enter all the relevant data and send it to the TDC - what I don't get is how you're supposed to be able to read off of the PK to see if your solution is holding up well over time. Using the screenshot below, can someone who really knows enlighten me as to exactly what these two arrow/indicators highlighted on the left side of the screen are supposed to be showing?

I thought that you were supposed to be able to look at the PK and read what it thought the range, bearing and AOB were, and then you could compare those PK values against your observed values after some elapsed time and thereby tell whether the solution was good or not. If that were the case, then I would have expected that arrow/indicator No.1 in the image above would be showing the PK's calculated AOB, but it clearly isn't. I also would have thought that the arrow/indicator No. 2 would be showing the PK's calculated bearing of the target from your boat, but it clearly isnt. (Both are off by some 20-30 degrees or more from the "actual" values seen in the scope, even though this shot was taken immediately after the values were sent to the TDC by clicking the red button on the dial in the top right of the screen (cropped out of this image).

It looks like arrow 1 is actually showing torpedo impact angle on the target and arrow 2 is showing gyro angle for the torpedo - both interesting tidbits but completely useless for trying to compare your observed data against the PK data to check your solution's validity.

So, what am I missing here (besides the targets)??

04-13-07, 01:14 AM	#1
panthercules The Old Man Join Date: Apr 2005 Posts: 1,336 Downloads: 6 Uploads: 0	Yet another TDC question - what do these show? Ok - I obviously do not have the hang of this US TDC. I've watched the Neal video (very cool) and read several TDC-related threads, but I still don't really understand exactly how this thing is supposed to work (even when it's not having it's bug with targets on the "wrong" side). I understand how to enter all the relevant data and send it to the TDC - what I don't get is how you're supposed to be able to read off of the PK to see if your solution is holding up well over time. Using the screenshot below, can someone who really knows enlighten me as to exactly what these two arrow/indicators highlighted on the left side of the screen are supposed to be showing? I thought that you were supposed to be able to look at the PK and read what it thought the range, bearing and AOB were, and then you could compare those PK values against your observed values after some elapsed time and thereby tell whether the solution was good or not. If that were the case, then I would have expected that arrow/indicator No.1 in the image above would be showing the PK's calculated AOB, but it clearly isn't. I also would have thought that the arrow/indicator No. 2 would be showing the PK's calculated bearing of the target from your boat, but it clearly isnt. (Both are off by some 20-30 degrees or more from the "actual" values seen in the scope, even though this shot was taken immediately after the values were sent to the TDC by clicking the red button on the dial in the top right of the screen (cropped out of this image). It looks like arrow 1 is actually showing torpedo impact angle on the target and arrow 2 is showing gyro angle for the torpedo - both interesting tidbits but completely useless for trying to compare your observed data against the PK data to check your solution's validity. So, what am I missing here (besides the targets)?? __________________