OK - anybody got a solution for this little problem? I've got my boat hidden on the nav map, and I'm trying to set my course and figure out where I'll probably be at dawn when I have to submerge. However, I'm still charging batteries, so when I use my engine telegraphs to set my speed, I'm of course going a few knots slower than usual at any given speed setting, and will be for a while till my batteries charge, then my speed will increase. This is going to complicate my navigational computations, as compared to being able to travel the entire time at a constant speed.

Therefore, I thought I would be able to get around this little problem by setting my speed to a specific number of knots on the alternate speed indicator. However, even when I try to order (say) 10 knots on that alternate indicator, I still only get about 8 knots while I'm charging batteries. You would think that when I order a specific speed, my engine room would give it to me whether I was charging batteries or not (assuming I wasn't trying to set it faster than my boat could go while charging batteries, which I wasn't), and would know to keep it at that speed once the batteries are full.

Is there any way to make the game give you a constant speed when you order it regardless of battery status?

[edit] Not a huge problem, I guess - my estimated position was only about 12.5 km off from my actual position after 8 hours' cruising. This is going to be very interesting :)

Ok, back on course with this thread, so to speak (I am terribly clever you see)

I have everything in order, but still at many of the closer zoom levels I see my boats little "circle" of radians given to me by my ubermods, anybody know how to erase these angles, as they give away the position of my boat!!

Thanks in advance,
Yarre.

Well if you know your going to get 8 kts when you order 10kts when charging you can work out your course using 8kts as speed
Recompute when charging over

Well, yeah it just makes the computation more complicated - no biggie but it would be nice not to have to do that.

OK guys, this is the file that I use for my "invisible" sub:
http://files.filefront.com/NSS_Uboat.../fileinfo.html

Feel free to use it if it will help you. My method for hiding my sub in the navmap is replacing the "zoomed-in" version of the sub with this blank transparent file, and then change the settings on the nav-map configuration file so that it will show the "zoomed-in" icons in all but the farthest of zooms.

And yes, using waypoints does give away your position, so refrain from using them unless you are very close to land (in which case it doesn't matter if your position is given away, your navigation officer should be able to fix your position on the map very easily if within sight of land)

Hmm - maybe it's just me, but after playing around with this for just a bit I'm beginning to think there's something a little backwards about the logical/theoretical basis for this approach. I like the concept a lot, but it feels like it's been implemented backwards. Consider this...

The "navigational uncertainty" that it appeared we were trying to simulate with this seems to me to be essentially that we shouldn't know exactly where we are in relation to the "world", i.e., the things we see on the map at the lowest zoom levels (zoomed furthest out from our sub), yet the way this is implemented we lose sight/track of our sub at the highest zoom levels (zoomed furthest in on our sub).

This has the effect of making it virtually impossible to plot and track contacts during the approach/attack phase (when zoomed in pretty close to our sub), when in reality regardless of how far off we may be from our expected position in the "world", we actually should have a really good idea of exactly where we are in relation to the enemy ships that are within detection range of our sub. If I spot an enemy ship bearing (say) 60 degrees at a range of 7,500m, then I know exactly (within reasonable spotting error ranges) where my sub is in relation to that ship (and vice versa), and I should be able to easily plot both of those positions on my nav map. Yet, with this mod/approach, I can't see my sub when zoomed in to these levels, and I've lost the bearing circle, so drawing a line from my sub out 60 degrees to the target becomes practically impossible.

It seems to me that if this could be flipped around so that you could see your sub on your map when zoomed in close but you could not see where your sub is on the map when you are zoomed fairly far out (at the levels where you would be plotting your major course settings and intercept plots for targets/convoys reported many km away, where the uncertainty as to where you are in the "world" would be most relevant), this would be a much more useful/realistic addition to game play.

Could this be flipped around like that, or will it only work the way it does now?

It can be very easily flipped around, then what you would need to do is get rid of the tail and sub circle icon, and change the nav-maps config file so that it goes into icon mode for every zoom but the highest zoom-in levels... It would work perfectly, except for two unimportant side effects: a) you would probably have to eliminate the tail from ALL the contacts. b) other sub contacts would also be invisible.

I would advise against it though... I think it's OK if you can look at your boat when zoomed realy realy far away. In my game I have it so that the sub appears on the map only when the zoom is so far out that the map is almost worldwide... I think this is good, because even the most incompetent of navigators can give you a rough guess of where you are (i.e.: "somewhere north of spain"). Even if you mark your position on the map when in such a large scale, when you zoom back in you'll find that your mark has a margin of error that can easily be a couple hundred kilometers... which is exactly the effect were looking for.

On the other hand, when you zoom in on the map, that's when the scale becomes more precise and meaningfull, and seing your sub at such scales would allow you to get a fix on your sub without any meaningfull margin of error (hence we make it invisible).

As to not seeing your boat in relation to the enemy boats when zoomed in... What enemy boats? The God's eye view should be turned off when you play hardcore :rock: !!!

It's not such a big deal... you don't realy have to know where in the map your boat is, because the enemy's position is never given in relation to the map, but rather, it is always given to you in values relative to your subs position... It's vector mathematics: translations and rotations of your axis of reference have no impact on the firing solution. If your sub is stationary, just pick any random point in the map and mark it as your sub's position and the plot the enemy's position relative to that. If your sub is mobile... well, it get's a bit tricky, but you still don't need to know your exact position to figure out a firing solution.

If I have the time I'll post more about this later.

These unique nav problems were not unknown to any navigator operating before the advent of GPS. Wx permitting, three celestial sightings were taken per day, dawn twilght, noon, and evening twilight...giving them a "RUNNING FIX". http://www.dtic.mil/doctrine/jel/dod...m/r/00949.html The "circle of doubt" aka assumed position aka estimated position, was always there--and still are today if you don't use GPS.

...also, to note--ships would make a degaussing run (demagnetize) when leaving the harbor and also run a known nautical mile--in this way, with stopwatch, they would time their track over the known course at a certain speed to determine their true speed and how much drag the undergrowth caused.

As was suggested earlier, wx permitting, do a noon sight (cntl/mouse click), place an "X" at the cursor...do a noon sight the following day aka ETMAL, place an "X". Now, measure the distance between "X's"...giving you your distance made good and course made good and S=D/T aka SOG (speed over ground).

Observing that when running free-lance (without using the waypoint tool) Wx, set, and drift will come into play causing you to drift off course and increase and/or decrease speed due to wind and current...welcome to a little piece of reality :)

edit: remember in the movie, "DAS BOOT", where the Navigator tosses his pencil at the chart in disgust when the Kapitän asks for a position? During that storm sequence, they were without a celestial sighting for over a week...that "circle of doubt" was growing larger by the day.

What enemy boats? The enemy boats that I have detected. I play with GW's normal settings (as far as I remember) so the enemy boats are not shown on the map (except I do still get some contact reports for convoys reported at some distance, but they don't move/update on the map) - but I do make marks on the map myself when I spot the enemy ships (visually or by hydrophones, although the latter are obviously just my best guess at distance based on my assessment of the strength of the screw noises so they have a large margin of error), and I like to be able to plot out the distances and such between my boat and the enemy ships I've spotted and am tracking through observations.

I realize that I can just pick any random spot on the map, pretend (for plotting purposes) that my boat is heading due north, and use the bearing circle pull down tool that always points "0" to the north to plot some relative bearings and distances (actually, it's the first time I've found a use for that bearing pull-down, which is kinda cool). In fact, I tried that last night when I stumbled onto a task force with an escort carrier (my first carrier sighting since day 1). I think it worked pretty well too, better than I expected, but I didn't get a chance to put it to a real test as I got detected by one of the destroyers and chased under before I could get into a good firing position (I went ahead and tried a long shot with a couple of T3s but to no apparent avail).

I think this is a pretty cool way of turning SH3 into a "navigator simulator" and not just a "captain simulator", and I think that's a pretty cool addition to the game play. I liked playing around as navigator during my course setting phases, having to make a decision about whether to risk surfacing for a position check at noon and risk being spotted by aircraft (which raised a question - could they do a position check through the periscope or did they have to surface?), and seeing how far off course I was from my estimated position when it came time to surface after dark to charge batteries, etc. And I found myself actually looking forward to a run of several days in a row of stormy weather to see what that would do to my course/position plotting. And I think it would be a good challenge to see if I could intercept a convoy spotted in a certain position on the map a grid or two away when I wasn't really sure where my own boat was.

I'm just not sure if I'm up for trying to be the navigator during the last phase of the attack approach when I need to focus most of my attention on being the captain, so I was thinking I might like it better if this could be flipped so that the navigator could take over and keep track of where we were at those high-zoom levels (simulated by my sub appearing on the map at those close-in levels) while masking my sub's appearance in the further-put zoom levels where I would be plotting intercept course on distant contact reports or setting course to my patrol zones, etc. If I have enough self-discipline to keep from using ctrl+click to locate my boat when I'm not "supposed to" using this method (and I do), I think I'd have enough self-discipline to avoid using my boat's appearance on the zoomed-in map levels to defeat the purpose of it not being visible on the zoomed-out levels.

I may give a try to flipping this around and see if I can make it work - thanks for the info and the inspiration - this is a really neat concept - it amazes me that folks are still coming up with such cool new stuff so long after the game's debut. Keep up the good work :up:

Forgive my "novice-graphics" but here is a rendering of nav/target problem:

http://img74.imageshack.us/img74/9048/aats2.th.jpg

Own course: 050T
Own speed: 13kn.

draw circle with compass with arrow pointing to 050T with length @ 13 to represent speed. (Use moveable protractor to locate course.)

Lookout spots target BR 315 (BR = bearing relative) range 9.1km, 315 + 050 = 005T. Use moveable protractor and ruler tool, mark with "X".

3:15 min later...

targert BR 295 range 7.4km, 295 + 050 = 345T, measure and mark with "X".

Use compass tool to layoff target's RELATIVE heading and RELATIVE distance travelled in 3:15. (distance between "X's".)

Pull the center of the small circle to the tip of own course arrow. (see drawing above)

Use ruler tool to measure from own location to tip of target's arrow. This is his TRUE course and speed, i.e., 060T 10.9kn.

This method is using the chart as a Maneuvering Board.

Excellent work guys :up:

I hesitate to report that I have found a potentialy big bug with our developing method... I discovered, while traveling through a somewhat strong storm, that the helmsmen don't do squat to maintain course heading. After you order something like "new course 45 degrees" the virtual sailors in your sub just make sure that your sub initialy points in that direction and then they let it go for itself without any course corrections at all (unless you set waypoints, but that would defeat the whole purpouse as already mentioned previously in this thread).

I was perfectly willing to accept problems with drift (that was part of the challenge we were looking for), but not problems with the boat being deflected off it's bearing by strong seas and not have the helmsman compensate by turning the boat back towards the intended heading... The stupid sailors behave as if they didn't have a compass on board :nope: . Under rough seas, in relatively short periods of time (about 4hours game time) I've had my boat change it's heading by about 15 degrees :huh:. So that means that you have to keep a very close eye on your compass heading because your crew sure won't :down:

No, Leeway, is not a bug, Dantenoc. It's a known variable-constant(wx, tides, current) confronting navigators daily, the reality I spoke of earlier. This, in effect, means that the waypoint tool as far as this game is concerned--training wheels.

I'm not sure I'm reading Dantenoc's post correctly, but it sounds like the actual compass heading is changing, and not just that the boat is winding up off course. To me, it would be one thing if the compass stayed set to 45 degrees but the boat wound up 15 degrees off course (that would be "drift" in my view), but it would be something entirely different if the compass heading actually changes from 45 to 60 degrees (which is what it sounds like Dantenoc is saying is happening) - that would sound like "crew incompetence" to me.

I had one stretch the other night where I wound up several degrees off course, further off than I expected to be or had been previously, but I didn't notice anything about the compass setting - I'll have to pay more attention next time and see if anything is going on with the compass heading.

:) I've been over this ground many times.

The sim compass always shows where your boat is heading. The simple test while in free-lance is to up the tc to x1024 and while on a particular course during foul wx...watch the compass drift right/left--this is indicating leeway--whatever the cause. As mentioned earlier, navigators relied on the ETMAL (noon to noon) position to determine COG, SOG, & CMG, SMG.
course over ground
speed over ground
course made good
speed made good

When landfall is made, one can fully realize and appreciate the joy and celebration due to the sailor, home from the sea.

There is nothing precise with real navigation due to all the variables involved, until the navigator can apply with mathematical certainty the discipline of celestial navigation to fix his position on the planet.

Leeway is omnipresent in both ocean and air. Nothing that flies or floats can avoid it. All we can ever hope to do is compensate for it. Many have experienced the phenomenon while crossing a bridge over a windy pass on a motorcycle, or hiking upon a windy trail. Navigating at sea or in the air presents unusual problems as there are no trees or hills to duck behind.

The navigator can plan a course from A to B, using D=SxT, but after leeway (wx, current, tides) take hold, he won't know how much drift or set have taken place until the time has passed, whereupon, he can compute the amount using vectors or maneuvoring board. Course A to B is always subject to change, the navigator can only guess his destination and put his ESTIMATED position on the chart...until it is confirmed or rejected via celestial fix.

Example of compensation:

own course 300T
we've determined 10° east drift
compensate course to 290T

Confirmation: Time runs out...was landfall made?

Gentlemen who navigate for a living indicate a course A to B in short segments, each segment was from noon to noon. They would draw a COG from one noon to the next noon, but it was only an estimate. Through celestial they would then fix their location and they could easily see the drift or set between the estimate and true fix. They would then draw their next COG segment from the fix toward their destination...this process is repeated day after day after day until port was reached.

Here's a typical nav worksheet mid-ocean showing courses adjusted by fixes:

http://img102.imageshack.us/img102/7494/afixgn5.th.jpg

I understand all the navigational theory, though I appreciate your explanation which is very clear and helpful. But I believe what Dantenoc was talking about was changes in the actual course indicated on the compass wheel. I just ran a brief test and while sailing for a couple of days at high T/C through variable winds (6 to 12 m/s) I did notice a very slight "trembling" of the compass heading indicator (which I would interpret as the boat being pushed off course occasionally and the helmsman correcting for it from time to time), but I also noticed that the compass seemed to have moved so that it was indicating a course of about 266 degrees instead of the 270 degrees I had "ordered" at the start. And, sure enough, when I plotted my position at the end of the run and compared it to my starting position, I was off by 4 degrees to the south of where 270 would have put me.

Now certainly, a variance of 4 degrees over that length of time (which amounted to about 30Km or so) seems reasonable in terms of drift/navigational error, and maybe the only way for the game to make this "error" occur is to actually change the compass indicator by the 4 degrees of the error. I guess it would just seem more realistic/normal if the compass heading would say 270 the entire time but you would still wind up being off course a few degrees like I was.

All in all, not any real problem at just a few degrees, though if I was seeing 15 degree variances it would certainly look odd to see the compass set to 255 when I had ordered 270. Also, seeing the compass deflected that way tends to telegraph the direction and extent of the navigational error, which we're trying to hide by suppressing the image of our sub on the map in the first place.