Need some advice for manual plotting

[Quillan]

I don't know if it's this way by default, but at least in Trigger Maru the nav map tools can be used while the game is paused. Pause the game, make your plots, resume the game. That will help.

Since I went to manual targeting, I haven't run a boat that didn't have SJ radar on it, so estimating the speed has been very easy for me. Without the radar, I think I'd have to be submerged and use the active sonar to accurately place the ship position.

[Nisgeis]

Originally Posted by Quillan

I don't know if it's this way by default, but at least in Trigger Maru the nav map tools can be used while the game is paused.

Yep, that's stock behaviour.

[Slick Wilhelm]

Thanks for the suggestions, guys. I appreciate the replies.

I forgot to add one more problem that rears it's ugly head each time. By using the active sonar to get target range, I typically use three pings each time, sending that data to the TDC. Now then, according to the 3 minute rule, I should be able to stop the chronometer right at 3 mins, then plot the 2nd mark. BUT, it's at this point that I need to record the bearing via the sonar station, and then ping the target three times. By the time I'm done doing all this, it's at least 3.5 mins. So, even when I switch to the NAV map and pause the game, I've already gone over the 3-minute rule by a good 25-30 seconds.

Surely I can't be the only one using this method and experiencing the same frustration?

[Nisgeis]

The pinging three times thing is only to give you the human an average reading, as the sonar gives you fairly but not very accurate readings, so taking three readings allows you to get an average reading. I don't think the TDC gets a more accurate range if you ping and send three times, or even ping three times and send once. In fact, it may make the auto speed thing record ranges that are jumping about and that may make your speed estimate worse.

I think as well that the stop watch auto speed calculater icon knows at what times you sent the readings, so you don't need to do it at exactly 3 minutes. The 3 minutes thing for the speed is for you to work out the speed in knots when plotting in yards - I think it's 3 minutes and 15 seconds or something for meters, haven't really looked at it in great detail. But anyway, the auto speed button only needs a few readings over a period, I dont think it needs precisely timed readings, so you should be able to plot and send to TDC independently. Try it and see what happens.

Edit: OK, I'm getting confused here. Are you trying to plot only by manual plotting, if so why are you sending stuff to the TDC? :hmm:

[Wilcke]

Originally Posted by Slick Wilhelm

Thanks for the suggestions, guys. I appreciate the replies.

I forgot to add one more problem that rears it's ugly head each time. By using the active sonar to get target range, I typically use three pings each time, sending that data to the TDC. Now then, according to the 3 minute rule, I should be able to stop the chronometer right at 3 mins, then plot the 2nd mark. BUT, it's at this point that I need to record the bearing via the sonar station, and then ping the target three times. By the time I'm done doing all this, it's at least 3.5 mins. So, even when I switch to the NAV map and pause the game, I've already gone over the 3-minute rule by a good 25-30 seconds.

Surely I can't be the only one using this method and experiencing the same frustration?

Ok;

1. At the mark, record the bearing.
2. Switch to Nav Map.
3. Pause
4. Plot
5. Un-pause
6. Go do your pinging.
7. Switch to Nav Map.
8. Pause
9. Plot the distance.

That could be a SOP.

I usualy plot the speed with the stadimeter. I do it severel times durring the Normal Approach Course or Optimum Approach Course from ranges of 7000 yards and in.

This gives you plenty of time to do lots of 3 min checks. I use the circle tool to plot the contacs, having the arrow part showing direction of travel of the target. Say i then have like 5 x 3 min plots over 15 min's i have the option of comparing them, and/or making an average (take the first plot's circle and enlarge it untill the edge of the circle intersects with the center of the last plot - divide the circles diameter with the total time from start plot to end plot and multiply that with 3 and divide with 100.

I have Cource Calculator slide rule next to me. Before starting my plotting i turn the wheel to my own course. From then its easy to very fast get a true to north bearing on the target from the wheel. What i doo is this:

1) NavMap Centered on sub
2) change to Stadimeter - make sure the left side TDC is open on the selection that shows ranges is present.
3) make sure you take the stadimeter range for the correct item (i use funnels) using the correct stadimeter setting (i use the manual input option on the masthead height)
4a) Scope up (All the way so it clears fast)
4b) take a bearing/range and note it on paper fast - estimate AOB
4c) Scope down (only untill its just under water - then stop it)
5) start stopwatch (only the first plot naturaly)
6) NavMap - linetool click on sub fast
7) ease off as from now you have 3 min's to make this plot before the next is up.
8) plot by extracting the line from the sub too the correct range read off the TDC and then i make a 300 ft. circle there. I let the radius arrow in the circle point in the way of travel.

I know the stadimeter is not the most presice tool, but for getting the speed correct in 3 min plots its mighty fine and more precise for us than it was in reality.

[Slick Wilhelm]

That's an interesting method, Mav, I think I'll give that a try. I didn't even realize that there's an arrow on the compass! I'll have to pay closer attention from now on!

Btw, is there a keystroke in TMO to center the sub in the nav map?

[Hitman]

Most people will tell you to do a plot with absolute bearings -i.e. plot starting from your sub icon on the map and keep the plot always from the sub's current position- but I found out long ago it is way easier to do it with relative bearings. Here's how to:

1.- Forget about starting from your sub, and go pick a place in the map where you can work and plot without distractions (An area of only water is ideal)

2.- Start by using vertical ruler to draw a line from bottom to top. This represents your sub's motion forward. Note your sub's speed.

3.- Now, scope up, get range and bearing to target. Start the chrono.

4.- From the initial point of the line you drawed in step 2) and using your ruler, draw a line in the bearing of the target. Use the compass in the tool helper to make it properly (Since the line you drawed is on course zero the compass in the tool helper matches exactly the scope bearing from your sub). Either use the compass in the tools or the ruler markings to make the line reach the proper measured target distance.

5.- 3 minutes later, up scope again and take bearing and range.

6.- First, calculate how much your sub has advanced in those 3 minutes with the easy mental rule. Now go that distance along the vertical line upwards and put a mark there. That's where your sub was when you took the second bearing Now pick again the ruler and draw from there the bearing and range to target of your second reading.

7.- Repeat as necessary to get a good speed reading. Serves also to get angle on the bow easily, which you can measure with your angle tool. If you want target's true course, you must add substract that AOB from your true submarine course. That's all.

Advantages:

1.- Simple to use with the game tools

2.- No hurry to plot from where your submarine icon is each moment. You have three full minutes to plot your sub's and the target's new situation each time.

Hope that helps.