Any tips for four bearings?

I'm not sure what I'm doing wrong, but my four bearings checks are always incorrect.

I was completely immobile here, 0 knots, and taking bearings every 10 minutes on a closing merchant.




Bearing 1 is the furthest left, Bearing 2 is middle, Bearing 3 is rightmost. I made 2 parallel lines from bearing 1 and 3, dropped them so they intersected mark 2, and that gave me intersections at mark 3 and mark 4. This should determine the course, right?



So then I start an on the surface run in the general direction and a different angle so I can get the real fourth, but in the interim I make my predicted fourth. To do this, I make a radius from where the course intersects bearing 2 to where it intersects bearing 3 (mark 4), then drag and drop, make a fourth bearing from my original position to where the radius intersects the predicted course.



So after another 10 minutes my run is done so I drop, get a final real fourth bearing and it gives me this line. Mark 6 is where my new fourth intersects the predicted fourth, so that is, from my understanding, where the ship SHOULD be, and then I dragged the course line down. Then the distance between where this course line overlayed on the real position intersects the third bearing and the real fourth should give me their speed? For this I got 3750 meters in 10 minutes or 12.15 knots.



So I setup in an attack position on the course and decided to turn on visual contacts to verify I was doing it right and... I wasnt. They were far away by a large margin:



In fact their real course wasnt even close



I'm really not sure what step I got wrong here, any ideas? I've not been able to get an accurate position or course no matter how many times I try. The tutorial in TWOS with the automation thing is broken so unusable. When it gets to the time accelerating part, it just kinda breaks and no ship spawns and time accel never happens. Not sure what else to do

[JackFlash81]

Tonci87 has created some amazing tutorials on YouTube. Check out his 4 bearings method while moving video:

I think to be more accurate using this method, it’s important to account for your boat’s movement from the time you get your initial celestial fix and to the time you decelerate to 1.5 kts while submerged. Like accounting for your location during acceleration to get your 4th bearing, I start my stopwatch right away, then take my current speed / 1.5 kts and see how far I traveled, using this average speed, for the time it took to slow to 1.5 kts.

Even though he didn’t account for this, he was still able to sink ships from a range of 4km!

[THEBERBSTER]

A Warm Welcome To The Subsim Community > JackFlash81
Subsim <> Make A Donation <> See The Benefits <> Support The Community
SH3 – 4 - 5 Tutorials > Downloads > Other Useful Information > See Links in My Signature Below

[THEBERBSTER]

Lawlcat
Let's learn to use RAOFB wheel in SH5 part 1-4.mkv By Stoianm1 > 4 YouTube Tutorials

Peter

[Aktungbby]

JackFlash81!

[Wolfcat]

Originally Posted by JackFlash81

I think to be more accurate using this method, it’s important to account for your boat’s movement

@Jackflash
Please note he didn't even use real navigation. You can see his true position on the map from the screen shots.

@Lawlcat
From my experience of using 4 bearing in SH5 is that you have to account for several things:

1. It's not necessarily the 4 bearing method is wrong. It may be due to your inaccurate bearing readings. The most common way of getting bearing reading is from the sonarman (hydrophone dial is too blurry to give you pinpoint accuracy). I found the longer the distance the less accurate the bearing report is. I tried 2 separate scenarios: 1 at extreme range near 30km and 2 at closer around 20-10km. The 1st scenario my calculations are way off where the 2nd scenario is pretty good . If this is true then 4 bearing is practically useless for long range contacts. (or you compensate with large time intervals)

2. AI ships sometimes do speed changes and course changes even though they never spot you. Don't know why, but there were multiple occasions I found AIs did that. Maybe you are unlucky that they did a course change between your measurements.

3. Tonci's method is good but very time consuming. I am not sure how many times you can do it in 2-3 hour game session. You not only have to keep track of the enemy movements but also you need keep track of your own. My preferred method is deep water (20 meters or more) stationary take 3 bearings at long time interval (i once did a 30min interval) and then sprint, course change, full stop, then ask for a dead reckoning all before you take the 4th bearing.

If executed right, I can get a pretty good fix. However, don't expect you can shoot the target blind. I usually use 4-bearing to get a decent fix and course on the target then use that info to plot an intercept plan. Once i get close then I still use traditional periscope approach to do the killing. From my experience, it's hard to achieve pin point accuracy so that you can use shoot it without visual verification.

[JackFlash81]

Hi Wolfcat,

Tonci87 is using true navigation. That initial fix is a celestial fix (the game automatically gives you one on your location once you load your save). I do agree, the method can be very time consuming, especially at first. I've got a save going on where I'm practicing it and am finding I get faster. For me, the challenge makes the kill that more exciting!

Yes, reading off the sonar dial really won't work for this, since we can't even zoom in. The way Tonci87 suggests is to have to sonar man lock onto the target, then as you get closer to your chosen time interval, see if you're close to changing, to get a better idea of their bearing.

Also, the ships are programmed to change course and speed on occasion, just like they would in real life to make our lives more difficult!

Anyway, one of my other favorite things about this game is that there are multiple ways of doing something. With Tonci's way, you can also do it stopped (I just like how he simplified some of the steps on the map, so you don't need to draw as many things), or do it moving. There are some other good youtube videos out there that show 4-bearings stopped as well. Hopefully, you'll find a method that works with your style of play!

Thanks everyone for the welcome! I've been studying up on all of the techniques listed for a while and am finally using real navigation! Sometimes, I wish I had 2 hands with all of the things I'm trying to do at once

[Wolfcat]

@jack
U misread me. I meant lawlcat didn’t use true nav in his screen shots. Without true nav, part of the equation is not an issue any more. If there is any issue, it gotta be the bearings r wrong. Btw, have u noticed that the bearing number on the scratch pad next to hydrophone is always one higher than what sonar man orally reports?

[JackFlash81]

I totally misread that! I didn’t notice the off by one on the read out vs. the dial. I go off the readout. Another interesting thing is I find it’s off by 1 degree when issuing new headings. The German response to my commands says the correct value, but the English text is off by one lol

[Wolfcat]

@jackflash

You mean the English text in the log at bottom right corner of the screen, correct? So I don't understand German, I need manually add 1deg to the text?

[Wolfcat]

Btw, how do I get an accurate initial position fix in heavy sea and heavy fog where I cannot get a good celestial fix?

[JackFlash81]

@Wolfcat
It's interesting, I'm using the voice commands mod, which adds a lot to the game. When I set my initial speed out of the sub pen to 2 knots, the German that comes back is for 1 knot (Eins is the German word for One), but the English text on the lower right pad are correct, so no need to add one there. Also, the ship does hold 2 knots. I do find that when they voice seeing smoke on the horizon, that the German bearing value they give me is correct. I guess it's just one of those quirks we'll live with.

When issuing headings, I use my mouse scroll wheel to get me close to my desired heading, since the voice recognition can get a little off and misread a heading of 185 as something way off. Once I get close to my desired course, I go to the radio room and use that compass to get me exactly on my course. The outer ring displays the first 2 most significant digits of your heading, and the inner ring shows the last whole digit and any tenths of a degree. So, If the line matches up with 140 and a little more on the outter ring, and on the inner ring I'm on the 4th line to the right of the 2, I'm at a heading of 142.4 degrees. This is accurate, and I find I have to change my rudder port/starboard by 1 degree increments to get me exactly on. Tonci87 pointed this out in one of his videos, which was a welcome bit of knowledge to keep me on course better! You'll want to periodically check to make sure you don't drift, which I find happens over the course of an hour or two. I can try and post a pic of the compass, if you'd like. I'm not sure if my wall of text on this makes sense lol

When you're in bad weather, you can't get a celestial fix, since the navigator can't see the sun or other stars. This happened in real life, and, unfortunately, you've got to either go with your dead reckoning fix, or wait the weather out. I've managed to get all the data I needed for my firing solution on a ship in bad weather visually, since I was close to them, and totally wasted a torpedo, since the seas were so rough, my torpedo went beneath the ship. So, if the weather is too bad, I try and shadow the target, and either get into visual range, or just follow them until the weather clears. Or, let that one go and look for another.

[Wolfcat]

@jack

Don't use the compass in the radio room. That one is still blurry. I use attack disc on the map. There is a switch to synchronize attack disc and boat motion. attack disc gives a much better compass than the one in radio room.