[REL] 3D TDC and Radar Range Unit

[I'm goin' down]

Originally Posted by John Channing

For 1) and 3): Once you start the watch it keeps running regardless of what screen you are in. Just hit the "X" key to make it appear. But I think you might be over using the watch for some reason.

To get a speed estimate just get a range/bearing at the radar station and head quickly to the plot. Put an "X" when your boat is. Then, on a piece of paper, write down the range an bearing. Afer 3:00 mins get another range and bearing and put an "X on the map where your sub is and write down the range and bearing. Then you can take your time to plot the two measurements on the map, measure the distance between the two results, subtract the last digit and voila... speed estimate.

For 2) It's a game limitation. You just have to get diciplined about switching back to the Range setting every time you leave the Periscope/TBT.

JCC

(bold added by IGD)

razar, channing and nisgeis-

My point about plot, was that the above post only mentions the "x". If you have to include the protractor angles, then time is awasting. You might as well pause the pause to make the entries. Also, the sub is on the move, and at flank can cover a lot of ground in 30 seconds. (Check the distance for one minutes at 20 kts.). That can affect the plotting of range.

razark, I was joking about the speed calcs. I use the 3 minute rule unless I forget to look at the stopwatch, in which case I convert to seconds.

razark, I did not know changing headings might affect the radar range and bearing readings adversely. If it is true, it is a good think to know. You might as well take the first reading when you are pointed at the target, otherwise you may have reading that are accurate but you could be getting further away from it.

[John Channing]

Unless the contact is moving away from you why in the world would you be at a flank bell? If the contact is closing you at all you will want all the time you can get to get your solution up, running and refined.

JCC

[I'm goin' down]

good point. the one I am now after was at 180 degrees and heading away, so I am chasing it..

[razark]

Originally Posted by I'm goin' down

My point about plot, was that the above post only mentions the "x". If you have to include the protractor angles, then time is awasting. You might as well pause the pause to make the entries. Also, the sub is on the move, and at flank can cover a lot of ground in 30 seconds. (Check the distance for one minutes at 20 kts.). That can affect the plotting of range.

As long as you're going in a straight line, it doesn't matter how far you've gone. As long as the "X" is pretty close to where you were when you made the reading, the angle should work. Jot down your bearing, range, and time on a piece of paper, and mark your "X" on the map. You can make several fixes on the target, each with an "X" to mark your position. When you have time, you can go back, draw in the angles and ranges, and figure out speed and course, without having to worry about getting back to the radar for your next observation right away.

Originally Posted by I'm goin' down

razark, I was joking about the speed calcs. I use the 3 minute rule unless I forget to look at the stopwatch, in which case I convert to seconds.

Hey, as long as you get the calculations right, you can use whatever units you like. Google says (10,000 yards) / (30 minutes) = 30,545.4545 furlongs per fortnight.

Originally Posted by I'm goin' down

razark, I did not know changing headings might affect the radar range and bearing readings adversely. If it is true, it is a good think to know. You might as well take the first reading when you are pointed at the target, otherwise you may have reading that are accurate but you could be getting further away from it.

Well, if you are trying to get a correct bearing on the target, and you're turning, holding the radar on it would be a bit tougher. The bearing you are trying to read would be constantly changing, and holding the beam to get the range would be a challenge.

[irish1958]

Originally Posted by razark

Hey, as long as you get the calculations right, you can use whatever units you like. Google says (10,000 yards) / (30 minutes) = 30,545.4545 furlongs per fortnight.

GREAT; this is the missing link for manual targeting

[Nisgeis]

Originally Posted by irish1958

GREAT; this is the missing link for manual targeting

Don't forget the other essential bits of info:

Range: 3.868734e-12 light years
Course: π/4 radians

[razark]

Originally Posted by Nisgeis

Don't forget the other essential bits of info:

Range: 3.868734e-12 light years
Course: π/4 radians

When the trig teacher said I'd be using this stuff later in life, this isn't what I expected!

[sergei]

Some Feedback:

Loaded up a single mission (TMO+RSRD) that had me patrolling just south of the Bungo Suido in late '42.

Target 1:


My initial 5 marks showed him going vaguely SSE, but I wasn't sure if maybe he'd made a turn at some point or was zig-zagging.
I put it down to inaccurate plotting on my part.
After I had marked points 6-9 I had a very good idea of his course. Obviously points 2 and 4 were aberrations. Possibly due to me not holding the beam on the target accurately.
I have worked out that at 30,000 yards a variance of 3 degrees gives you a possible error of 1700 yards!
So, obviously at long range you are just trying to get a sense of the targets general direction of travel.
As the range drops it becomes easier to get accurate plots and possible bearing errors have much less of an effect.
As the range dropped you can see my marks becoming a lot more consistent.
You can see the second plot I started when the target was close enough for me to get accurate stadimeter readings. It's pretty damn close to my radar plot.
And I sank the bugger right in the middle of my two plots.
Very satisfying.

Target 2:


I can see a pattern developing here
Again marks 1 to 5 are not consistent enough to give the targets true course yet, but they are good enough for me to decide which direction I need to head for the intercept.
As the range dropped I decided that marks 8-10 were probably close enough, so that's what I predicted his course as with the ruler.
As he got into visual range I would take occasional stadimeter readings just to check that he was still on the course I had predicted. I measured these, but as they showed him still on track I did not bother marking them.
In this attack I noted the time of my initial contact was 3.55am.
I made a visual mark exactly one hour later at 4.55am (not shown, I accidentally deleted it whilst deleting all my ruler marks and range circles ).
The distance between that mark and my first was 10.2 miles (IIRC) so I used 10 knots as his speed.
Worked like a charm.
You can see where I got him, very close to my predicted track.

I am very much loving this mod

Once I was close enough to get a stad reading I activated the PK and would watch the attack develop on the TDC (occasionally taking another range reading to keep it updated). It gave me a real good feeling for what was going on. Looking forward to JC's tutorial so I know what most of the dials are for

A thought: whilst switching off the radar between readings may make it easier to use because it remembers your last range and bearing, doesn't that also switch off your air search radar? Or is it always on regardless of the state of your surface search radar?

A question: my Gato had listed in the equipment screen an early SJ radar with a range of 20,000 yards. However, I was getting contact out to about 40,000. Is that to do with this mod, or have I FUBARED my game again?

[I'm goin' down]

very nice demonstration w/screenshot. where was your boat during all of this. Was the target closing, etc.?