target speed: the eighty-ten method

[Diopos]

Originally Posted by Armistead

...
The real tool is radar, not the blind use of sonar. This appears to be using your elbow to scratch your arsehole.

Well not exactly, developing tools and methods that allow you to estimate the target's vector via PASSIVE sensors is always a plus (even more so for a sub).


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[Nisgeis]

You aren't explaining this very well greyrider, it would help if you answered some of the questions, instead of going on a rant about the plagurism of mathematical concepts that have been around for centuries.

Are you sying that this method only works if the AoB is ten degrees? If it isn't then this method won't work and you just have to try it to see if it does work and then you'd know if it worked (if your torpedoes hit)? If that's NOT what you're saying, how can you just assume that the AoB is ten degrees when you turn to have the target at a relative bearing of 80 degrees? That's a very specific setup, where you would have to be in a very specific place, e.g. very small distance to track and you'd need to be at right angles to his track.

[Nisgeis]

Originally Posted by Diopos

Well not exactly, developing tools and methods that allow you to estimate the target's vector via PASSIVE sensors is always a plus (even more so for a sub).

That would be useful, but this method is apparently only for determining the magnitude of the vector (target speed), for which you already need to know the vector direction (target's course (AoB)) and be in a very specific position ahead of the target, just off the target's track. I'm still unclear how the OP is saying that we will be in that position, in order for this to work.

[Diopos]

Guys lets give the man some breathing space, eh!
As I said the fact that the method is based on keeping the target on a constant bearing while the same time your sub is keeping constant course and speed is a very good starting basis. It signifies that you're either running parallel to the target or that you're on "collision/post collision" course (converging or diverging). It is the mathematical part of it that needs expansion and the fact that suplamental target information/estimations are required (to narrow down the set of probable solutions) IMO.


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[Munchausen]

Originally Posted by Rockin Robbins

Well, no, it could BE 180º! hehehehehe!
But then your speed to keep it on a constant bearing would be zero or infinitely variable without restriction, depending on your course.

By now I'm sure you realize your speed could be most anything equal or below target speed if you're following in his wake.

[Pisces]

Originally Posted by greyrider

http://www.filefront.com/user/greyrider
ok, well to put all doubt to rest about 8010, the link above is the original mission i used to test out the 8010.
if your going to try the mission, as soon as it starts, make sure you put 2 knots on the sub knot meter, and dont do any turns,
this is a real easy misssion, in order to see how the 8010 works, all you will have to do is make the sub go forward at 2 knots asap after the mission starts..

Greyrider, I opened that mission in the mission editor but I don't think it's the right file. (8010mission.rar) There is only a (german) IXD2 in the south atlantic with a waypoint set towards an objective area to arrive. But nothing in the area to attack. And in the Indian Ocean 2 US destroyer escorts, a US Escort Carrier and a US divebomber. Nothing that compares to your video.

[Rockin Robbins]

Originally Posted by greyrider

hey rr, this is a picture from the TFCM, says we can,


By null at 2010-08-17

That diagram says nothing of the kind. You do not understand the diagram or the trig calculation. To use it you need angle on the bow. Your method does not develop angle on the bow. Lacking one of the necessary parameters, you cannot solve the trig equation. That is elementary. Actually this diagram has nothing to do with your method. It simply is a method to calculate target speed based on the other parameters if you have established a collision course. It would be very useful if you understood it.

i put up a mission, that says we can,
i made a movie, that shows we can.
now show me yours, that says we cant.

Your mission says nothing of the kind. Your movie proves nothig of the kind. I Don't need a mission. Just use my Dick O'Kane targeting mission (puts the target at a random position within limits and lets you hunt and kill it). Using only the methods revealed in your movie and posts, you'll be able to do nothing to develop an attack there! Why? Because unless you luck out and begin with an 8010 relationship, you have not developed a technique to acquire one. In contrast, the Dick O'Kane technique similarly depends on a unique 90º relationship between target track and own course, and achieving that relationship is part and parcel of the attack process! AND it does not abandon that relationship at the end of the attack to set up a completely different approach in order to land the torpedoes. You totally gloss over the fact that you ditch the 8010 to achieve a 90º approach and do a by guess and by golly lead the target by eye and shoot attack. Your 8101 hocus pocus served only to get you close to the target and had nothing at all to do with the shot itself, which you did not explain at all. Not one single person learned how to operate their submarine better from your three videos, many posts and claims of being first and best. Face it. Neither one of us is first by over seventy years.

Diopos already posted the chart that completely invalidates your method, proving that you establish neither target speed or course. In fact he shows that you could be on a perfectly parallel course affording no chance at a shot at all!

and why would i read the cromwell method, or anything else you wrote, which i consider inferior, when its just a step child of point and shoot, which is highly flexible, and where your things
come out "AFTER", and the key word is after, someone elses...blah, blah, brag.

First of all gutted has more understanding and ability to teach in his little toe that in all your posts combined, which rely on smoke and mirrors to confuse, not clearly instructing people who desperately need to learn how to shoot a torpedo. These people are frustrated with a very complicated game! Learning to hit a target is the difference between a happy player and someone who abandons SH4 forever. Confusing them pushes them over the edge of the cliff, convincing them they can never learn to shoot. Poppycock! I can teach a six year old to shoot as well as I can.

Second of all, Cromwell, O'Kane and vector analysis don't develop because they are complete within themselves, needing no improvement either in technique or explanation. With three methods of instruction, video, written and flash cards, ANYONE, possibly including my cat, can use any of the three techniques successfully the very first time they try. The instructions are completely clear, don't depend on any specially set up conditions and work perfectly in the random encounters of real life or a SH4 career. Hundreds of people have been successful using these and I wasn't the only one to develop them. They were developed in cooperation with many other similarly minded people.

The keys to success are simplicity and clarity neither are present in 8010.

funny how point and shoot keeps on getting better and better, while cromwell and company are not
improving over time as point and shoot does, that proves to me that you dont have any originality,
and that whatever you write about is derivable, from somebody else!
you know, if i was to do a cromwell type shot, i do any angle i feel like, if im not developing a deliberate attack, then im making a hasty attack, ...etc, etc, brag, brag

Again, Cromwell and O'Kane do not improve because they are self-contained special circumstance methods that work perfectly, are easily explained. There are no improvements to be made, any more than the equation "1 plus 1 equals 2" can improve or develop. In fact improvement or development would not prove that they are not derivative. It would prove that I got them wrong to begin with. Of course the techniques I teach are derivative, but not from anything of yours! They are derivative from techniques actually used in World War II submarines. At all times I explain this, document it with screenshots from the Submarine Torpedo Fire Control Manual of 1946 and other period sources establishing the historical reasonableness of using the techniques I teach. I have never claimed the originality, nor do I see its necessity as you do. And I have never based any technique on your work.

The vector analysis method is a more general purpose method adapting to any relationship between target course and own course. But it also is self-contained, concise, easily understood and taught, needing no further development or improvement. Like "2 plus 2 equals 4" it is slightly more complicated than "1 plus 1" but equally complete, needing no "improvement" or "refinement."

I contend that you have no instructions here that anyone can imitate beyond how to establish a collision course with a target. Oops, you don't have that either because you purposely set up the 8010 relationship in the scenario and began the whole shebang with your submarine on the correct course and at the correct speed, which you didn't adjust even once! So you have not even taught how to get your sub on that collision course.

Greyrider, let me toss you a bone. In astronomy we often can't establish target course at all and have no way to calculate an "AoB" type measurement. We use a term called proper motion. This is assuming a course at 90º to us, how many degrees per unit time is the target moving? We can then predict its arrival at any other bearing, assuming it moves in a straight line. Since all constant bearing attacks cancel range out of the equation and therefore only guarantee a hit at any range on a particular bearing, can't we apply that to a random targeting situation, normalizing it to a 90º approach?

Just thinking here and not using any diagrams or experiments, we see a target out there. We take a bearing, finding that he bears 340º. Just for fun, we estimate a range of 2000 yards and draw a line at range 2000 yards at right angles to our course. Using our bearing, we plot a position on that line. Three minutes later, we plot another bearing on the line. Our course is wrong and our speed is wrong, we know that. But let's go with it. Enter the speed using the 3 minute rule for the two points. Enter AoB at 90º (we'll shoot at bearing zero). Send the zero bearing to the TDC and leave the PK off. I say that no matter what the angle really is, the shot will hit. Now THAT could be used with sonar instead of visual measurements, the only important factor being whether the torpedo has the range to reach the target. Of course, the closer the range, the more likely the hit, but here is a clear set of instructions, adaptability to a wide variety of encounters, and no smoke and mirrors.

Hint: combine your "technique" with the principles I explained above to arrive at a real targeting technique. Do you see the profound difference between my approach at teaching and yours? I thought not. I'll let you founder in your own maelstrom.

[Pisces]

Originally Posted by Rockin Robbins

...

Just thinking here and not using any diagrams or experiments, we see a target out there. We take a bearing, finding that he bears 340º. Just for fun, we estimate a range of 2000 yards and draw a line at range 2000 yards at right angles to our course. Using our bearing, we plot a position on that line. Three minutes later, we plot another bearing on the line. Our course is wrong and our speed is wrong, we know that. But let's go with it. Enter the speed using the 3 minute rule for the two points. Enter AoB at 90º (we'll shoot at bearing zero). Send the zero bearing to the TDC and leave the PK off. I say that no matter what the angle really is, the shot will hit. Now THAT could be used with sonar instead of visual measurements, the only important factor being whether the torpedo has the range to reach the target. Of course, the closer the range, the more likely the hit, but here is a clear set of instructions, adaptability to a wide variety of encounters, and no smoke and mirrors.

I'd still like to see a drawing to go with this, if you please. Since I don't understand how or why that line at 2000 yards is plotted. You state it is perpendicular to own course. Are you sure it's not supposed to be perpendicular to the bearing of 340? Or is it perpendicular to own course because the bearing is set to 0 in the TDC when you set the AOB to 90. Well, I'm probably just having trouble understanding because I'm tired as a dog.

[Nisgeis]

Originally Posted by Pisces

I'd still like to see a drawing to go with this, if you please. Since I don't understand how or why that line at 2000 yards is plotted. You state it is perpendicular to own course. Are you sure it's not supposed to be perpendicular to the bearing of 340? Or is it perpendicular to own course because the bearing is set to 0 in the TDC when you set the AOB to 90. Well, I'm probably just having trouble understanding because I'm tired as a dog.

Think of it as drawing the target's track, where your distance to track is 2,000 yards and you are on a normal course (your course is at right angles to the assumed target course in the direction to close the distance to track). You plot the points where the target's bearing intersects the (theorhetical) target's track, so you only need to worry about the bearing and not the range.

I don't believe it will work though in every case though, as the rate of bearing change won't be constant as it will change with the range, as the target is moving in a straight line (hence the TMA methods working), whereas with astronomy it's bearing movement due to rotation, which is going to be fairly constant.

[Rockin Robbins]

Originally Posted by Pisces

I'd still like to see a drawing to go with this, if you please. Since I don't understand how or why that line at 2000 yards is plotted. You state it is perpendicular to own course. Are you sure it's not supposed to be perpendicular to the bearing of 340? Or is it perpendicular to own course because the bearing is set to 0 in the TDC when you set the AOB to 90. Well, I'm probably just having trouble understanding because I'm tired as a dog.

I'll work it up in another thread. Nisgeis could be correct about the rate of degrees per unit time changing as the range changes, lending some inaccuracy to the plot. That was simply a thought experiment, not backed up by any real analysis. You have to remember that in astronomy, stars essentially have infinite range and zero size. The situation is much simpler than with a submarine in some respects. The important thing will be to analyze how tolerant the method is to angles not exactly 90º. In other words are you pretty okay 30º off in either direction? 45º? At what point does the angle become a deal-killer? If plus or minus 30º would give you a 60º slop factor with a pretty guaranteed success wouldn't you take that as useful? You could pretty well visually narrow it down that far without measurement. But if the tolerance is only plus or minus 15º we might not be so happy.

By the way folks, Nisgeis is primarily responsible for popularizing the vector analysis method. He originated the concept and chose the name of the John P Cromwell method. Many times he has set me straight when I got something regarding the TDC slightly (or greatly) wrong. Please take a bow sir!

[Barkhorn1x]

Originally Posted by Rockin Robbins

By the way folks, Nisgeis is primarily responsible for popularizing the vector analysis method. He originated the concept and chose the name of the John P Cromwell method. Many times he has set me straight when I got something regarding the TDC slightly (or greatly) wrong. Please take a bow sir!

Hey Rockin', where can I find the vector analysis write up for the John P. Cromwell method? Your link goes to your vid and your basic write up. I want to get a step by step rundown on on the vector work seen in the vid.

Thanks in advance.

(Cancel this request. Found it. Good stuff. Now, armed w/ the JPC and DO methods, what can go wrong? )

[Barkhorn1x]

OK - another - related request. Can anyone point me to the link that describes - in a step-by-step manner - how to do a Stern/MOT/Bow distribution w/ the JPC method?

Thanks.

[Rockin Robbins]

Please take it to the Bag of Tricks thread. This thread isn't for that.

[greyrider]

amistead, you asked how we could track convoys using this method, i dont have time to do a mission or make a movie, but i did
draw a couple of things, to show you how you can track certain ships in a convoy, for whatever purpose you want to.
first you have to understand the width of the sound signal is twenty degrees, in the first drawing you see the sub pointing north,
well, i forgot to make a sub icon, but its down at the point where all the lines meet.
the red thing is the target heading south, the green line is zero degrees, and the target is on bearing zero.
you lay your hp needle on 0 and you hear the sound signal and it has the strongest amplitude, as you move the needle away
from zero , the sound begins to drop off in decibles, its really noticable on more than one bearing as you sweep away from the true bearing,
on either side of the true bearing of the target.
finally, at 350, and 10 degress, the sound drops off entirely, and you cant hear the targets screws, so really, at bearing 349 and 350, and at 10 and 11 degrees, is where we should be
listening, to detect acute bearing changes, and direction of movement,
if we are to man the sonar station ourselfs, it applies to all bearings.
if the target is on zero degrees, we can hear the target on bearing 350, very faintly, and at bearing 349, we wont be able to hear it, same on the other side
at 10 we will hear it, at 11 we wont.
if the target goes to 359, then you will hear it on 349, on 348 you wont. on the other side it will be heard at 9, and not at 10., this indicates bearing change
and a port aob, because if it continues, the target will pass you on your port side with port aob. the same will happen with the other side, but will have a starboard aob.
this is not the sound width i use to estimate range tho, just direction of travel and bearing change, r to sub, acute bearing changes.
the one for range is different, its the same signal, but instead of using the weakest part of the signal for direction and change, your using the strongest part of the signal for range
and how it defuses over multiple bearings, how it overcomes ambient sound, and defuses wider and wider as it draws closer and closer.
the sonobuey records at nha are great for learning passive sonar, you hear an instructor, describe a sound that he wants you to hear, and then plays it.
anyway, appling this to a single merchant to target is easy, but a convoy is another story. but you can still do it, in the bulk of the convoy,
you hear many screws, and you cant figure out what sound belongs to whom, but on the other edges of the convoy, you can get credible sound signals from
a couple of ships, to track, estimae bearing changes and direction of movement. theres two ships in particular, you could put on a 80 offset to track speed,keep constant bearing,
remenbering the 20 degree sound signal, look at the second drawing, see the convoy heading east, sub pointing north.
staring from 0 degrees, the sonarman sweeps west, the first screws he gonna hear will be the first ship in the first column, the farthest one away on the first row,
with the leading edge of the hydrophone needle,
so if the green indicator light comes on and you hear screws at bearing 26, that far merchant is at bearing 16, the closer you sweep your needle toward the far ships true bearing,
you will get interfernce from another ship, and the signal will be useless for anything, so you would have to use the bearing where sound is heard as far away from its true bearing on its right.
in the drawing you see this ship with a green 1 on it, this is the ship i mean, and the brown line is the leading edge of the hp needle.
the other ship that can be tracked for speed, as well as the other stuff, is the last ship in the column thats closest to the submarine, here you listen with the trailing edge of the hydrophone needle, letting the hp
needle pass by the true bearing of the target, and listen to the fringe bearing to its left, and avoid interference with another ship.
this ship has a 2 on it, in the drawing.
these are the only two ships in the convoy that we have a chance to track, and gather information from, but once we have thier numbers, we have the convoys numbers.

By null at 2010-08-19


By null at 2010-08-19

[Rockin Robbins]

That's a great method because our sonar guy is worthless when we're trying to track a convoy!