Clear the Bridge! Dick O'kane method

[45_South]

Greetings all,
I am trying to get my head around manual targeting and am currently reading Dick O'kanes' Clear the Bridge (very good read too by the way).

I started out using "the Dick O'kane' method as tutorialized (don't know if that's a real word but I'm going with it) by Rockin Robbins. I understand this method and have had some success with it - set up at 90 degrees to target track, offset aiming device 10, fire as desired points cross crosshairs etc etc.

However, every attack I read about in Dick O'kanes' book goes something like this (after the initial setup) "Constant bearing - mark!"
"Set!"
"Fire!" and the first torpedo went for her big stack aft. The next fish went for her middle, and the third forward.

What I don't understand is if he is firing as the target moves across his periscope crosshair, how does he shoot aft to fwd? This implies that he in fact does not hold his scope on a pre-determined bearing to fire but rather tracks with the target from aft to fwd?

I must be missing something basic here... calling Rockin Robbins to the bridge!
p.s. I tried to find the original Dick O'kane thread to post this to but failed miserably there also :-?

[cleverusername]

The periscope reticle has markings in degrees that show where the various components are located. So you can see that the bow, middle, and stern compartments are located at 3 degrees left, dead ahead, and 3 degrees right. Then you use the offset feature in the TDC to aim the torpedoes at those locations on the ship.

I don't believe the "Dick O'Kane" method posted on the Subsim forums is historically accurate. Dick O'Kane, trained as a wartime US submarine skipper, would have used all of the features of the TDC and position keeper as originally designed, instead of the shortcut method posted here.

[Rockin Robbins]

Greetings all,
I am trying to get my head around manual targeting and am currently reading Dick O'kanes' Clear the Bridge (very good read too by the way).

I started out using "the Dick O'kane' method as tutorialized (don't know if that's a real word but I'm going with it) by Rockin Robbins. I understand this method and have had some success with it - set up at 90 degrees to target track, offset aiming device 10, fire as desired points cross crosshairs etc etc.

However, every attack I read about in Dick O'kanes' book goes something like this (after the initial setup) "Constant bearing - mark!"
"Set!"
"Fire!" and the first torpedo went for her big stack aft. The next fish went for her middle, and the third forward.

What I don't understand is if he is firing as the target moves across his periscope crosshair, how does he shoot aft to fwd? This implies that he in fact does not hold his scope on a pre-determined bearing to fire but rather tracks with the target from aft to fwd?

I must be missing something basic here... calling Rockin Robbins to the bridge!
p.s. I tried to find the original Dick O'kane thread to post this to but failed miserably there also :-? The clue here is in Dick O'Kane's calling "Constant bearing — mark!" Those words have a precise meaning that cleverusername doesn't believe is historically accurate. Let me put on my professor's cap and go to work here.

There are three methods of shooting torpedoes, according to the Submarine Torpedo Fire Control Manual (http://hnsa.org/doc/attack/index.htm), which I invite you to read to verify what I say.

The first method, and the one cleverusername refers to as "historically accurate" is the check bearing method. In the check bearing method, the captain makes the announcement "shooting will by the check bearing method" or some shorthand with the words "check bearing method" in them. This is a quick up and down of the scope to get a bearing, range and down scope. This method emphasized minimal, less than 30 second scope exposures to take a snapshot that could be plotted. They developed course, speed and bearing by multiple observations and checked the actual periscope bearing method (thus the name "check bearing method") against that of the TDC with PK on. When they were happy with the solution, they took one last observation to update bearing and range and shot with spreads set with the spread dial.

The second method is the continuous bearing method. In the continuous bearing method, the periscope is left up and constant bearings are continuously fed to the TDC to keep the TDC continuously updated with real bearing and range during the shooting of the torpedoes. As long as your speed and course are accurate, this is a very accurate way to shoot. You do expose your scope for a long time though. In certain situations it is very useful.

The third method and that referred to by Dick O'Kane in his book is the constant bearing method. There are many variations of the constant bearing method, but what they have in common is that the TDC is set for a solution and the periscope is aimed for that bearing. When the aiming point crosses the bearing you shoot, knowing the torpedo is going right where you aim.

Think of it this way. If you're shooting cute birdies out of the sky with your shotgun, there are two basic ways to get the job done. One is to sweep the shotgun across the sky with the bird until you're satisfied with the lead angle and shoot any time you want. This is the analog of the check bearing and continuous bearing methods. The second way is to anticipate a position in the sky the bird must cross, aim your gun there without moving it and squeeze off the murderous shot at the correct moment. This is the analog to the constant bearing method because your gun is aimed at a constant place in the sky. Kapeesh?

Dick O'Kane would start his attack the way we do. He'd work with the PK and tweak the inputs until his TDC was following the target perfectly. But to shoot, he'd sight ahead of the target, send a new bearing and crank the TDC bearing input backwards (more details available from Nisgeis or aaronblood) to stop the updating. We can do the same thing by clicking off the PK. Then he would wait for the target to pass by the crosshair, shooting as the part of the ship he wanted was on the line. He could do this quickly enough, sighting again ahead, waiting and shooting again to shoot his stern, MOT (middle of target), bow spread. He shot in that order to give him the maximum divergence in his spread. That made the attack more difficult to avoid if the torpedoes were spotted. Check out a John P Cromwell attack in broad daylight with a perfect longitudinal spread and you can see how easy it is to avoid a spread with no divergence.

We made it very clear when we published the Dick O'Kane method that we had no proof that Dick O'Kane ever used that exact methodology in his attacks. We did know he liked to use the constant bearing method and shoot as juicy parts of the target "crossed the wire." With the goal in mind of making a deadly attack method that eliminated every possible detail, while remaining awesomely lethal, what we named the Dick O'Kane attack is an adaptation of Wahoo's Fast-90 U-boat method, but using the capability of the American TDC, which automatically calculates the lead angle and allows you to set up the attack before you even see your target.

The real Dick O'Kane and the three of us who developed the Dick O'Kane attack had different things in mind. Dick O'Kane didn't care how difficult it was. He had a highly trained crew to back him up and could do several things at once. His attack would be very difficult for a beginner to execute.

My goal was to encourage the new player who had never tried manual targeting to give it a try, with the assurance that he would be a certified killer right off the bat. Frankly, it worked much better than I planned with many experienced players using the method often. At no time have we ever claimed that Dick O'Kane used this exact procedure. He did use very similar constant bearing methods, though, and they did use the American TDC in imaginative and very unconventional ways. The constant bearing section of the Torpedo Fire Control Manual has Dick O'Kane's virtual fingerprints all over it!

OK, enough defending. How are you going to do the max divergent spread with the Dick O'Kane method. It's really not too difficult. You will have to give up an infinitessimal amount of accuracy, because we're not going to have time to update the AoB during the shooting. We'll be perfectly accurate on the second shot, OK?

Let's say our normal shoot bearing is on the 10º bearing and our ship is about ten degrees long. So we'll set up our speed. Then we'll set up the AoB for that 10º shot--90-10=80º starboard or port, depending on which side he's coming for. Our first shot will be intentionally five or seven degrees before the perfect bearing. Point there and wait for the ship.......when that fat stack on the stern is in the crosshairs, shoot!

Now aim the scope just in front of the ship and hit the send bearing/range button. When the MOT is on the crosshairs, shoot! No time to dawdle here.

Again leapfrog to ahead of the target and press the send range/bearing button. When the bow crosses the line shoot as the mast crosses the line.

You've just shot the stern, MOT, bow spread, Dick O'Kane style! Your AoB settings were slightly off, but not enough to make you miss. You have 3 hits on order, American Express overnight delivery. Splice the mainbrace!

[Orion2012]

One question RR, when you said they "crank the bearing input backwards" do you literally mean they, physically jammed it up, or did I misunderstand?

Nice explanation though, very well said Professor Robbins.

[45_South]

Let's say our normal shoot bearing is on the 10º bearing and our ship is about ten degrees long. So we'll set up our speed. Then we'll set up the AoB for that 10º shot--90-10=80º starboard or port, depending on which side he's coming for. Our first shot will be intentionally five or seven degrees before the perfect bearing. Point there and wait for the ship.......when that fat stack on the stern is in the crosshairs, shoot!

Now aim the scope just in front of the ship and hit the send bearing/range button. When the MOT is on the crosshairs, shoot! No time to dawdle here.

Again leapfrog to ahead of the target and press the send range/bearing button. When the bow crosses the line shoot as the mast crosses the line.


Thanks mate! I will try this method and see how it goes. To be honest I was getting a little frustrated with manual targeting and went back to auto for a single mission to 'start again and build some skills' but it was like shooting ducks in a sideshow alley.

The last sub sim I played was 688 Attack Sub and things have obviously changed a bit since then and I think I got bogged down in all the mods (latest RFB etc) available with this sim and lost the plot on learning the basics.

Also, thanks for the link to the Fire Control Manual and I really appreciate your time and effort in such a lengthy and detailed reply. Hats off to you Sir :up:

[Very Jerry]

While we are talking about the various tutorials and videos that help us landlovers understand the tactcs faster and more clearly, I personally want to thank Rockin Robbins, W Sobe and others for all their efforts. I would still be using auto targeting without them.

[Rockin Robbins]

And that, folks, is why I keep it simple. I credit manual targeting as the reason I still play the game. After awhile auto targeting is like shooting fish in a barrel, but manual targeting is just darn intimidating.

By eliminating every possible step, while rejecting shortcuts that sacrifice accuracy I've frustrated those better shooters who, for instance, know how to execute a perfect constant bearing attack without being on a right angle or a 45º angle to the track. But I've opened the door for people who thought manual targeting was black magic or Einsteinian mathematical wizardry with attacks that:
Don't require calculators, charts or any outside materials like plotting paper, protractors, is-was banjos or ouija boards. Those things are all good, but not for the methods I teach. I use only in-game tools and simple rules of thumb that are easy to remember, but still methodologically accurate.
Are reduced to a recipe that anyone can accomplish just by following the steps. You have a great chance of sinking your prey on the very first attempt. Just by reading the instructions you know that you can do this. Confidence is crucial when you're learning something new.
Are precise and precisely explained. There are no made-up undefined terms. If I say "longitudinal spread" you can be sure that if you look it up in the Torpedo Fire Control Manual, you'll see what it is and its definition.
Are for the purpose of producing skippers who are better than I am. Some instructional posts are heavy on the bragging and light on instruction. I want YOU to brag when you're done putting awesome amounts of Japanese shipping on the bottom.Well, apparently there's no way to double-space the entries in that list.:nope: I keep some of the links to my stuff in my siggy. I also extensively use WernerSobe's [REL] Video Tutorals: TDC + PK advanced (http://www.subsim.com/radioroom/showthread.php?t=118923) thread. I just kind of adopted it after WernerSobe was lost at sea. Also, look up tale's Multi-ship targeting videos. They're very good.

You might also search for John P Cromwell Technique, which Nisgeis and I cooked up. It's pretty interesting and has Nisgeis' method of vector analysis so that you can calculate a constant bearing shot from any angle to the track with a perfect zero gyro shot. It's more advanced than I would normally put in an instructional video, but just using it once reveals that the apparent complexity is just a cruel hoax. You can do it in seconds, and in-game too! No outside references unless you need a torpedo speed chart.

In order to run, you must first learn to walk. And it's great if while you're only walking you can do some interesting things, like blow up enemy shipping. Just please make an agreement with me. After you learn to run, don't make fun of the people who are still walking. Don't make fun of simpler methods as "unhistorical" or "shortcuts." There are plenty of runners who still use the Dick O'Kane and John P Cromwell techniques to their profit. And some of those walkers, like I'm goin' down, will be passing you in skills in a month or two!

My goal is to build a submarine fleet so good that I'm not qualified to be a skipper in it.

[I'm goin' down]

Having just got my head and boat around manual targeting with a moderate degree of success, I was on top of the world (or, should I say above the surface) until I read this thread. Hell, I am just an amateur compared to you battle hardened subsim computer nuts. It is back to the books for me, and you have just wrecked my Thanksgiving holiday as I will be unable to sleep for the next month trying to understand and implement what I have read in this thread. And I was just about ready to tackle Warner Sobe's sonar only tutorial, thinking I was ready for the elite ranks ....

Whoever said, "The inmates are loose and running the asylum" probably got their start here. The infantry is looking better every day....

[Rockin Robbins]

Whoever said, "The inmates are loose and running the asylum" probably got their start here. The infantry is looking better every day....

:rotfl:The way I look at it, if you're still learning, you're not dead yet. My goal is to be not dead yet for quite a long time to come. You're doing great and your posts show you understand what you've learned. You're not just parroting, you're reasoning. That's the mark of success.:up:

[I'm goin' down]

Now he's calling me a parrot! I have to squawk about that one.http://www.subsim.com/radioroom/images/icons/icon10.gif

[Fish40]

I actually got my first kill the other day useing the DO method! RR great tutorial by the way:up: I got a radar contact at 10nm. I slowed to 1/3 speed and began my first plot. Three minutes later I took another reading and plotted. After determining his course, I got in position 90 degrees to his track and set up the TDC as per the tutorial.

The one thing I have a problem with is getting an acurate speed, which is essential with this method. Since the Radar screen dosn't have range rings, it's hard to determine exact distance between the two plot points, so therefor measuring the distance between the two points will yeild an inaccurate figure. I actually find it a challange to aquire a visual, get an ID, and measure the time it takes for the target to cross the 0 bearing line to determine speed.

Anyway, after I did all that, (target was a Hog Islander by the way) I sat and waited for the target to cross my 10 degree bearing line. I fired three shots: One at the forward crane, one under the stack, and the last at the aft crane. All three shots impacted, but my speed must have been off a hair because the shots hit further aft of their intended AP. She went down about 20 minutes later after slowly flooding:yep:

It seems to me, once you have an accurate speed, the rest is sinfully easy!

[I'm goin' down]

The turkey awaits the hatchet, but I could not resist RR's invitation. A fleet without RR at the tip of the spear is like a kid playing with submarines in the bath tub. Unfortunately for the tike, he is now out of baking soda, so the fleet is doomed to sail around aimlessly until the war's end or until dinner is ready. Solution: give him airhog helicopters and tell him hs days as a submariner are finished.

(My crew has spent the morning painting Betty Grable in her bathing suit on the torpedos with a note on the nose cones saying, "Ain't life a blast!)

[pythos]

Wow, that is a variation of the method I have adopted lately, with great success. Plot a course 90 degrees to the targets path, use the TBT on the bridge to get the targets course data get the solution into the TDC with PK on, while moving at full or flank till aprox 3000 yards from the target's course. Then submerge, and go to silent speed, and wait for the target to be called out at 45 to 30 degrees by the hydrophone operator, with a visual check every 5 minutes. At my speed of 1 knot, and the target's usually being 11, the firing point is normally achieved at around 1200 to 1000 yards. When ready to fire I open all the tubes who's torpedo's have had all the deph, pistol and speed setting set. Pop the scope up for final observations, and then turn off the PK. My scope then continues to send bearing info to the tdc. I line up the part of the ship I want to put a fish at, and fire. For large ship I fire at the stern foraward with three fish. For medium, one fish just behind the stack, and one under the stack. For small targets one fish at the stack. Lower the scope and wait.

Mind you, because I play as a captain with a full crew (meaning I have a torpedo plotting team) I have auto tdc selected in gameplay options. So the TDC getting bearing info with the PK off may not be accurate, not sure. I tried manual and found me as captain doing the stuff the plotters would be doing...and sucking at it:) I wish that there was an options page for auto TDC that would allow you to choose the features you want enabled, such as being able to determine bearing, and range, and have the plotters figure out the speed, and angle on bow along with other items. I figure the plotters could get the angle on bow by determing the target's course in relation to mine, cause I know I can't figure it out with scope observations. Also I would like to disable the triangle with auto TDC on.

But that being said, the method I use seems to work well, unless the target changes course, or sees the steamers headed for them.

[tater]

I've been testing a new escort out, and so I've been trying to get DCed.

As a result, I am watching in external. I've found that I can eyeball using the sub marker on the surface, and hit ~50% of the time at 2-3000 yards just shooting from the hip with no data at all, lol.

[Rockin Robbins]

Sounds like fun tater!:up: I guess you can tell I am a strange mixture of a person who appreciates realism but is always ready to play with the gaming aspects once in awhile.

I don't have any problems leaving my career, loading up a scenario and my subnuclear cuties (I know, not released yet. I've been lazy). Then I play with how close a 30 knot cutie has to come to the target before it will turn to follow. Really you have to come pretty close or it blasts on by.

But that idea sounds like a lot of fun. Are you just going zero gyro and aiming with the arrow on the marker?

[Admiral Von Gerlach]

Remarkable work here. Much to study. And ys the US skippers did indeed use the tools they were given in very creative ways...and got results too. thanks for these excellent postings and all the info for a shellback to study.

[Fish40]

Ckalk up another one with the DO method:up: I recieved a radar contact at 10nm, bearing 75 degrees. I turned towards the contact and reduced speed. I took a bearing and estimated range and made my first plot. Started the stopwatch for 3 min. took second bearing and estimated range. I determined that the target course was NW.

I plotted a course 90 degrees to the target track, and prepared the torpedoes and TDC. Monitoring the radar screen, the range began to close until the "ship spotted" alert rang out. Training the TBT at the announced bearing, I saw the outline of a ship in the darkness. He's getting close now.

I swung my bow around just ahead of him, and timed him as he crossed the 0 bearing line of my TBT. It took him 21 seconds. At this point I fear he may see me, so I go to PD. I up the Obs. Scope (useing the color filters mod; I use the yellow one. ) and ID him as a Medium Modern Comp. Freighter. I have a list that I hand wrote of all the ship lengths. Useing the simple formula to find speed, I determined him to be going 10k.

At this point everything is set: TDC, torpedo speed and depth, target speed and AOB. Nothing left to do but open the outer doors and wait for the ship to cross my scope. Two Mk 14's speed off and impact 30 seconds later:rock: About a half hour after that, down he went. I'm truely beginning to love this targeting method:yep:

[Nisgeis]

One question RR, when you said they "crank the bearing input backwards" do you literally mean they, physically jammed it up, or did I misunderstand?

Nice explanation though, very well said Professor Robbins.
The input crank is one of the eight at the bottom of the TDC. The crank can be used to set the bearing in the same way that a winder on a clock can set the time forward or backwards. When the TDC is running and the bearing of the target is being advanced by the computer, the operator will manually crank the bearing crank in the opposite direction, keeping the bearing on the TDC contant.

An analogy would be trying to keep a clock at a fixed time, whilst it is running, by winding the spindle that allows you to set the time backwards. This is one of the 'skilled' parts of being a TDC operator. Anyone who has ever used a lathe or milling machine will know the skill and dexterity you need to feed in at a contant rate so as to give a uniform finish.

The difference between using the crank to keep the bearing matching the aim point and turining the PK off, is that everything is updated. As your ship and the target ship are still closing each other down, or possibly moving apart, if you are in a bad position, the problem is changing. With the TDC running and the bearing being held everything, e.g. the range, AoB, torpedo run length, gyro angle order etcetera are updated with the new problem.

[Nisgeis]

The one thing I have a problem with is getting an acurate speed, which is essential with this method. Since the Radar screen dosn't have range rings, it's hard to determine exact distance between the two plot points, so therefor measuring the distance between the two points will yeild an inaccurate figure.

I take it you are running with map contacts off? You could try using my radar range mod, it's in metres, so you'd have to convert it, but it is quite accurate for manual plotting.

[Nisgeis]

Right, just had a quick check of the functional diagram for the TDC to check my facts. There is a very subtle, but very important difference between the real TDC and the in game TDC.

The real TDC has the bearing input crank connected via an adder to the target course (relative tagret course is what the TDC refers to it as, but it's the same as AoB). The in game TDC does not. What this means is that when you adjust the bearing, the target course (AoB) also alters to match. We know from the other explanations about how to get the AoB by drawing it on the map, that the AoB is the angle between the target track and the bearing to your sub. If you can imagine the target moving up and down the target track (like its on a rail) then as the bearing changes, so does the AoB by the exact same amount.

For example, if a target is deads ahead of you at a bearing of 000, steaming a course relative to you of 090, then when the target was at a bearing of 315, the AoB was 45 and when the target will be at a bearing of 045, the AoB will be 135. So that's the maths behind it, the relationship between the AoB and the bearing is a simple addition/subtraction.

The target course is also connected to the range counter by an integrator, so changes in the target's range and course, due to its own movement are taken into account.

What does this mean? It means that with a real TDC, when you hold the bearing you are keeping the course the same and this means that the solution you have is always valid for the point where your scope's aiming wire intersects with the target's course (regardless of where the target is. The target's speed is fed into the gyro angle solver, so the torpedoes will be sent on their way to intersect with the target as long as your speed estimate is correct. You are effectively making the TDC simulate a constant bearing reducing range problem for the aiming point. You are basically on a collision course for your aiming point and the target moves accross the aiming point.

This is all quite confusing and is hard to visualise without a diagram, but the basic principle is that the stern has a different relative course than the bow, when seperately viewed. In game, as the TDC does not change the AoB with a change of bearing, then winding the bearing back will not work accurately, as you'll get a different course. This should only generate a small error however. It's easier to try to visualise this if you imagine an infinitely long target.

Sorry if none of this made any sense.

[I'm goin' down]

After a lesson from RR, I came accross a merchant in the Mallacca Straight near Singapore. I overran it in pitch darkness, and had to chase it through the night after it spotted my boat, in order to salavage a firing position. I finally was able to set up for an eyeballed broadside at around a thousand yards. The merchant was cloisng from my starboard--its port, at 22 degrees, so things were moving right along. When it hit 10 degrees in the crosshairs, I started unloading torpedoes-six of them- in the rapid sequence, firing as follows: 1. at the bow, 2. at the aft mast, 3. at the command tower, 4. at a point about half way betweein the command tower and the stern mast, 5. at the stern mast, and 6. at the stern. I set the range on the stadimeter before letting them loose, as instructed. Six for six, with torpedoes iimpacting in sequence from aft to sterm. There was such noise caused by the the impacts that my three toy poodles went racing through front doggy door in a state of hysteria, intending to find and sink their chops into the trespasser who foolishly dared invade their space and make such a racket. I closed the door behind them, and watched contentedly as my prey slid under the waves. My crew voted unanamously that I should quit while I am on top. I doesn't get better than this.

[Rockin Robbins]

Nisgeis, that was a GREAT explanation why the real TDC was better than the game TDC at constant bearing shots. In short, with the ability to crank the bearing input backwards (there are clutches inside the TDC that allow this to happen so everything isn't "hard wired" together with gears. Think about it, you couldn't crank in the bearing to begin with if that weren't true:rotfl:) they had a real-time AoB update with the change in TDC bearing similar to that modeled for the U-Boat TDC in SH3 and 4.

The real submarine had no need to be at 90º or 45º to the track. We only do it in the game because it allows us to use simple rules of thumb to input the AoB. Dick O'Kane the person didn't have to do that.

For SH5 I think they need to ship a new computer peripheral: a little USB crank that you can use to make inputs into the TDC, and which coincidentally, you could use to crank backwards to perform the REAL Dick O'Kane maneuver.

Now, to change the subject, I'm goin' down, by the power vested in me by WernerSobe, Nisgeis, aaronblood, gutted, and the infinite might of man's imagination, I hereby dub you Knight, First Class, of the Dick O'Kane Manual Targeting Technique. May you use it well and wisely, always for the forces of right, good and and niceness. and never for the agents of evil and rottenness.

[I'm goin' down]

Knight is great. I wll ride a sea horse into battle. But right now, I am listening to sonar only tutorials and then I will return to decipher Nisgeis' masterful explanations.

[Rockin Robbins]

Is SUBSIM a great place or what?:up:

[I'm goin' down]

Trying to install Jammimadrid's mini chron and tools got my machine out of whack and I was up until 5:30 a.m. reloading the game, mods, etc. I have given up on the tools aspect and ancient 46 is reviewing my mods and the mini chron, so I may get them in sync this year. Meanwhile, my WEBSTER'sS deck gun, which I downloaded as part of package of his mods for 1.5, takes between 17 and 18 seconds to reload. rahter than 2 seconds as he indicates. I confirmed it on my FULL SIZE stop watch. And, my source of relief, the CaptainsGirls, GirlsInEveryPort, and Captain'sDeskPhotos mods do not show anyone, yet alone, women. Oh yea, that and a destroyer that has a sonar man who never sleeps, and is on my ass, makes this sim something, but I am not sure what.

[Fish40]

The one thing I have a problem with is getting an acurate speed, which is essential with this method. Since the Radar screen dosn't have range rings, it's hard to determine exact distance between the two plot points, so therefor measuring the distance between the two points will yeild an inaccurate figure.
I take it you are running with map contacts off? You could try using my radar range mod, it's in metres, so you'd have to convert it, but it is quite accurate for manual plotting.


I saw your mod Nisgeis, and it looks like it would definitely be useful. I do keep the map contacts off for a more realistic experience. I was wondering if your mod is compatable with the latest RFB:hmm:If is is, I'll be downloading pronto!:yep:

[I'm goin' down]

With map contents off, I do not have to worry abouit speed because I never find anything. How do you find a target?, besides by pure luck?

[I'm goin' down]

How do you find a target with map updates off besides by pure luck?:hmm:

[Fish40]

How do you find a target with map updates off besides by pure luck?:hmm:



Presently my current patrol is in 44', so I have Radar to find my targets. But besides that, if you patrol along known shipping routes you will hit paydirt eventually. Also pay attention to radio messages. There may be info of a convoy or taskforce. And of corse don't forget periodic hydrophone checks, especially if you don't have radar.

[jazzabilly]

according to the Submarine Torpedo Fire Control Manual (http://hnsa.org/doc/attack/index.htm), which I invite you to read to verify what I say.

Weeeeew~ Thanks for this. I will print this out and giver 'er a read.

[XLjedi]

I actually got my first kill the other day useing the DO method! RR great tutorial by the way:up: I got a radar contact at 10nm. I slowed to 1/3 speed and began my first plot. Three minutes later I took another reading and plotted. After determining his course, I got in position 90 degrees to his track and set up the TDC as per the tutorial.

The one thing I have a problem with is getting an acurate speed, which is essential with this method. Since the Radar screen dosn't have range rings, it's hard to determine exact distance between the two plot points, so therefor measuring the distance between the two points will yeild an inaccurate figure. I actually find it a challange to aquire a visual, get an ID, and measure the time it takes for the target to cross the 0 bearing line to determine speed.
.
.
.
It seems to me, once you have an accurate speed, the rest is sinfully easy!

Why are you trying to measure speed on the radar scope anyway?

In your first paragraph you mention that you have acquired the target at 10nm and you plot two points to determine true course (presumably on the navmap). Once you have the TC plotted you should be setting yourself up for a submerged attack on a 90° beam to the target TC.

As you make your submerged approach, the hydrophone operator will call out bearings to the target that you can plot on the TC line. If your TC plot is good, the distance between those points should be plenty accurate enough for a good speed calc.

[XLjedi]

Oh BTW,

My response to the original OP's question would be... In that instance O'Kane was using a lateral spread.

You can do that easily by locking your scope on the target midship and turning that degree offset dial. You'd wait for the middle of the target to reach the desired bearing and then dial: 2° fire, 0° fire, -2° fire

How do I know 2° is right? I just lock on the target midship and then look on the scope to see how many degrees I needed to offset to hit the various parts.

Now in fairness to O'Kane, this method that bears his name is no longer a good reflection of what you and I read in his book. If you want to see how I originally proposed mimicing Okane you can read my post here:
http://www.subsim.com/radioroom/showpost.php?p=627351&postcount=134

RR chose to simplify it. I choose to bash him over the head http://www.xl-logic.com/emoticon/fight.gifonce in awhile for dumbing it down to the point where the TDC isn't even used!

Also, I don't recall that Okane would necessarily line up on a 90° beam to the target. He took a standard 90° approach to the target bearing, but that's something different. There's more evidence in his books that suggests he (and Morton) preferred to fire after the target passed the 90° beam so the torpedos would 1) not impact at a right angle, and 2) the ship would have a harder time evading (never really studied this one, but I trust Morton knew what he was talking about).

[Rockin Robbins]

Nope, you're right. I can't see any evidence that O'Kane sought a right angle to the track. He might have had a preference for angles that were close, but I don't see any evidence for it.

I think you're right about him using the spread input to hit the bow and stern of the target in that instance. Please note that per the Submarine Torpedo Fire Control Manual, this would have been a computed spread of about 80%. He wouldn't have been just fiddling with the spread dial and hoping the setting was good. That would have earned him a good roasting by his friend, Admiral Lockwood, when he got home.

Hey! That's not fair! I use the TDC. It computes my lead angle and dries my oilskins when I come below in bad weather!:88)

[XLjedi]

Now I do take a lot of 90° shots... but in those cases I also set the torps for magnetic detonation and try to swim them under the keel. I just got tired listening to the things bouncing off the sides of ships (an all too frequent occurance for right-angle impacts).

[XLjedi]

Please note that per the Submarine Torpedo Fire Control Manual, this would have been a computed spread of about 80%. He wouldn't have been just fiddling with the spread dial and hoping the setting was good.

At what point did I say that he was, "just fiddling with the spread dial"? :doh:

I think he did exactly what he said he did in his book. He targetted midship, then looked at the rear stack, determined it was offset 2-3° and fired his spread accordingly.

[tater]

O'Kane says in Wahoo that Morton liked 120 degree approaches best.

[jbt308]

I see all these Florida boys posting and just had to pipe in!

Have to thank RR for his tutorial on radar-only DO technique shoots. To say that I was dumbstruck when it actually worked(my skill, not the teachings), is an understatement.

A ship came up on radar, so I hopped up to the bridge to take a look around. Pitch black, no moon, 15m/s winds, heavy fog and rain; just one hell of a storm. So I decided to try out the "no eyes on target" method you spoke of.

Tracked the mark down his path, waited till he was a heartbeat past 20' and loosed my last 3 fish. Blew him out of the water at approximately 4000 yds, I couldn't even see the explosions it was so dark!

Thanks again to all that post here and make the game more enjoyable! And maybe for the next Subsim get together in Texas, we can form a Florida caravan!

[I'm goin' down]

I was running ahead of a tanker to set up for a Dick O'Kane salvo, but was so far ahead of the SOB I brought my boat around for a Cromwell shot. Then the SOB changed course, so I abandoned Cromwell and set up for manual targeting per Hitman's tutorial. I put my last four torpedoes into her, had a beer, followed her for three hours, but she never sank! (It's not dinner until its in the pan!) I concluded the mission by running aground somewhere near Singapore and sinking.

[Munchausen]

I don't recall that Okane would necessarily line up on a 90° beam to the target. He took a standard 90° approach to the target bearing, but that's something different. There's more evidence in his books that suggests he (and Morton) preferred to fire after the target passed the 90° beam so the torpedos would 1) not impact at a right angle, and 2) the ship would have a harder time evading (never really studied this one, but I trust Morton knew what he was talking about).

O'Kane liked the night surface attack. Visually, a 90 AOB is one of the easiest to identify ... especially if the ship has side-by-side masts. A skipper could approach at 120 degrees (as Tater said) and, as long as the TDC was set for 90, send a final bearing when the target looked to have a 90 AOB ... then fire. He could then reposition on another target ... again waiting until seeing 90 degrees before sending a final bearing to the TDC.

[XLjedi]

Just to clarify, since a couple people now appear to have commented on my statement about the 90° target bearing standard approach; it has nothing to do with a 120° approach to the target true course.

It's just the standard approach an XO would take by putting the target bearing on a 90° beam moving (presumably) in the same relative direction (at this point AoB is an unknown). Then the captain would be informed... and then perhaps after an observation (or several) an AoB determination can be made and then maybe a 120° to TC would be the prefered approach angle for attack.

Okane mentions in Wahoo that as the XO he puts the boat on a standard 90° approach and then informs Morton of the situation. It's a method that's also documented as the standard approach in the torpedo fire control manual. It doesn't mean that you're on any particular approach angle to the target true course.

It looks like this:
http://www.xl-logic.com/mobo/tutorial_pics/Standard_90_Approach.png
The standard 90° approach for target M1 or M2 is 330° and we don't really know what the true course is yet for either one.

This is a first contact (and probably at considerable distance) approach. Granted I've exagerated the M2 contact here because in this case we wouldn't actually be closing (approaching) on the target. I should probably redraw it with an acute angle, but I don't feel like doing it again...

[XLjedi]

Visually, a 90 AOB is one of the easiest to identify ... especially if the ship has side-by-side masts. A skipper could approach at 120 degrees (as Tater said) and, as long as the TDC was set for 90, send a final bearing when the target looked to have a 90 AOB ... then fire. He could then reposition on another target ... again waiting until seeing 90 degrees before sending a final bearing to the TDC.

I have to say though...

I'm not sure why it never dawned on me to try this before! :doh:

...seems so obvious. :yep:

RR you all might want to consider looking into this one and dubbing it the "Morton" with all appropriate credit to Munchausen of course. ...or dare I say it, a true Fast-90 for fleetboats?

[Urge]

jbt308 wrote...
Have to thank RR for his tutorial on radar-only DO technique shoots.

Did I miss something? I must have been in the back of the room playing cribbage with the boys(I bet there are some really good cribbage players on this forum, too bad we couldn't have an online cribbage game just for subsimmers). I don't recall reading about a radar only tutorial from RR. There is a Radar approach video tutorial from tale, could this be the reference?

Urge

[tale]

jbt308 wrote...
Have to thank RR for his tutorial on radar-only DO technique shoots.
Did I miss something? I must have been in the back of the room playing cribbage with the boys(I bet there are some really good cribbage players on this forum, too bad we couldn't have an online cribbage game just for subsimmers). I don't recall reading about a radar only tutorial from RR. There is a Radar approach video tutorial from tale, could this be the reference?

Urge
No, he is not talking about my video, because it doesn't even touch the attack phase by far. I think he meant The Dick O'Kane Sonar Only (by God!!!) Video (http://www.subsim.com/radioroom/showpost.php?p=1025180&postcount=1) third in the list of RR links

[Rockin Robbins]

Visually, a 90 AOB is one of the easiest to identify ... especially if the ship has side-by-side masts. A skipper could approach at 120 degrees (as Tater said) and, as long as the TDC was set for 90, send a final bearing when the target looked to have a 90 AOB ... then fire. He could then reposition on another target ... again waiting until seeing 90 degrees before sending a final bearing to the TDC.
I have to say though...

I'm not sure why it never dawned on me to try this before! :doh:

...seems so obvious. :yep:

RR you all might want to consider looking into this one and dubbing it the "Morton" with all appropriate credit to Muchausen of course. ...or dare I say it, a true Fast-90 for fleetboats?
I think we have the seed of a new idea here. It could also take advantage of standard convoy behavior. You hit the first target, the convoy goes into St Vitus' dance, then settles back to the original course and speed. You wait for another target to present a 90º AoB, rinse and repeat. Often even with a convoy making 12 knots, the St Vitus dance period results in milling around essentially in place and you can reposition ahead for another shot if necessary.

This has a lot of potential and the "Morton Technique" name is a good idea. Munchausen, your name goes on it and aaronblood, as usual, your vision is 20-20. I don't want to muddy the central concept of the Fast-90 technique, which was the direct connection of the U-Boat periscope with the TDC, automatically recomputing AoB for changing bearing on the same target track. In reality fleet boats could do that too, according to Nisgeis, but it is not modeled in the game.

When my new power supply comes, hopefully Friday, this gets added to my already daunting list!

[tater]

The scattering of convoys is interesting in that it differs from Task forces where they constant-helm, but tend to hightail it away.

For the game, there is one difference between a TF, and a convoy.

The lead unit.

Have 20 warships lead by a single merchant... it's a Convoy.

Have 20 merchants led by a warship? Task Force.

Might have to do some testing on this.

[Munchausen]

O'Kane (or maybe it was Calvert ... the books are all back at the library now) missed a shot one night (during a surface attack) and surmised that it was because he'd gotten the speed wrong. This was his second or third target and, evidently, the convoy had either sped up or slowed down. He never mentioned target course. Ergo, I suspected he was eyeballing AOB.

Awhile back, somebody else at this forum mentioned how you could shoot a 90 degree AOB without actually having your sub pointed perpendicular to target track ... the comment kind'a went unnoticed. But, putting two and two together, I figured it would best explain how a skipper could take on multiple targets, at night and on the surface, and miss only if he got the speed wrong.

Unfortunately, night surface attacks are hard to do in SH4. I've read where gray-painted subs could sometimes get within 500 yards of a target without being detected. If there's a mod that simulates this, I'd like to know about it.

[tater]

Not all convoys scatter, I attacked one last night and the 1 damaged tanker, and the only un-hit merchant (4 ships with a MS and an XPC escorting) steamed on at 7 knots while the 2 I stopped, foundered.

[BillBam]

This has a lot of potential and the "Morton Technique" name is a good idea. Munchausen, your name goes on it and aaronblood, as usual, your vision is 20-20. I don't want to muddy the central concept of the Fast-90 technique, which was the direct connection of the U-Boat periscope with the TDC, automatically recomputing AoB for changing bearing on the same target track. In reality fleet boats could do that too, according to Nisgeis, but it is not modeled in the game.

When my new power supply comes, hopefully Friday, this gets added to my already daunting list!

Just wondering if this method was ever cataloged and had any videos created?

[I'm goin' down]

thought I would drop in and show off my newest sig. Waves to RR, Nisgeis, and all.:D

[Admiral8Q]

thought I would drop in and show off my newest sig. Waves to RR, Nisgeis, and all.:D
Very nice, but you should put the text part in italics:cool:

[Munchausen]

Just wondering if this method was ever cataloged and had any videos created?

I don't think so.

:cool: I've been using this method exclusively in SH3 ... after installing MaGui (it has a button on all applicable 2D screens to switch from manual to auto TDC). The method really works great for surface attacks ... especially after you've blown your O'Kane-type setup. Just put the TDC in manual mode, input target speed (you still must figure that one out yourself), set an AOB of 90 degrees, WAG an intercept course, lock your target, wait until it's in profile, press the button for auto, and fire a spread.

As long as you're in manual mode, the target's AOB will remain at 90 degrees. As long as you're locked (and in manual mode), the scope/UZO will maintain azimuth ... but the TDC bearing won't move. Switching to auto-TDC just before firing sets the TDC bearing to your target's current azimuth ... while leaving the AOB at 90 degrees.

:/\\k: In other words, you now have a proper firing solution. If your target's speed is correct, you can even unlock and delay firing so as to pick your sweet spots.

For Fleet boats, it's a bit more complicated. The TDC works differently.

[BillBam]

I don't think so.

:cool: I've been using this method exclusively in SH3 ... after installing MaGui (it has a button on all applicable 2D screens to switch from manual to auto TDC). The method really works great for surface attacks ... especially after you've blown your O'Kane-type setup. Just put the TDC in manual mode, input target speed (you still must figure that one out yourself), set an AOB of 90 degrees, WAG an intercept course, lock your target, wait until it's in profile, press the button for auto, and fire a spread.

As long as you're in manual mode, the target's AOB will remain at 90 degrees. As long as you're locked (and in manual mode), the scope/UZO will maintain azimuth ... but the TDC bearing won't move. Switching to auto-TDC just before firing sets the TDC bearing to your target's current azimuth ... while leaving the AOB at 90 degrees.

:/\\k: In other words, you now have a proper firing solution. If your target's speed is correct, you can even unlock and delay firing so as to pick your sweet spots.

For Fleet boats, it's a bit more complicated. The TDC works differently.

Unfortunately in SH4 you either have manual or auto, you cannot change once you start a patrol.

[Munchausen]

:-? I think the problem with Fleet boats was, when locked on a target in Manual mode, sending a bearing to the TDC also changed the AOB. If the AOB Mod freezes the target's AOB (until PK is activated), then the method might work.

[Liberatus]

Hello everyone.
Is it possible to effectively use Dick O'Kane method in an attack on the convoy from a long distance (2km or more)?

[Pisces]

Yes, but the further out the target is, and the shorter his length, the better you need to know his exact speed.

Take his length, and divide it by the range, i.e. 95 yards at 3000 yards is 31.7 yards per 1000 yards. 1 degree is 17.5 yards wide at a 1000 yards distance (same values apply if you use meters instead of yards), so the ship is 31.7 divided by 17.5 = 1.8 degrees wide. If the TDC aim is off by halve that angle (=0.9 degrees) then you risk missing the target if you aimed at it dead center.

So how do you know how accurate the speed must be? First you need to know how to convert speed to the lead angle.

The lead angle is based on the target speed, the speed of the torpedo, and the AOB of the target.

The formula is:

lead_angle= arcsin( Target_speed x sin(AOB) / Torpedo_speed )

(sometimes the arcsin button on a calculator is shown as "sin with superscript -1" or "inv sin" or "asin", or if you want to avoid that and allow yourself some inaccuracy simply multiply with 57.3 to get degrees. But this only works because lead angles are generally speaking quite small. You can't avoid the proper arcsin button on your calculator if the angle is more than 20 degrees)

Let's say for example, it has 90 degree AOB ( sin(90)=1 ), 10 knots speed and the torpedo moves with 31 knot:

lead_angle = arcsin( 10 X 1 / 31 ) = 18.8 degrees

(or 57.3 x 10 x1 /31= 18.5 degrees, ... and notice this simplification already cost you 0.3 degrees in accuracy)

The lead angle is roughly proportional to target speed. That means if target speed is actually 5% faster than 10 knots (so 10.5 knots), then the required lead angle is also about 5% more. (with our example: 19.8 degrees is required for 10.5 knots) Do you see the difference? 1 degree. If you thought it was doing 10 knots but in actuality it moved 10.5 knots, then the torpedo would pass behind the target. Because the stern is 0.9 degrees behind the center at that range. If it is further out, then the 0.9 degrees size would turn into a smaller value. And if the AOB is not 90 degrees, it's appearant size is even smaller. (times sin(AOB) )

You can easily get the speed wrong by 0.5 knots if you rely on the 3-minute plotting rule and use the 'crude' maptools (at those short track-lenghts). To get an accurate speed you need to average the distance over multiple 3-minute intervals.

As you might have noticed, a fast torpedo also help to reduce the lead angle, and limit the aiming error based on speed.

[Dogfish40]

Now, to change the subject, I'm goin' down, by the power vested in me by WernerSobe, Nisgeis, aaronblood, gutted, and the infinite might of man's imagination, I hereby dub you Knight, First Class, of the Dick O'Kane Manual Targeting Technique. May you use it well and wisely, always for the forces of right, good and and niceness. and never for the agents of evil and rottenness.

:har: That was good!!

Trying to install Jammimadrid's mini chron and tools got my machine out of whack and I was up until 5:30 a.m. reloading the game, mods, etc. I have given up on the tools aspect and ancient 46 is reviewing my mods and the mini chron, so I may get them in sync this year. Meanwhile, my WEBSTER'sS deck gun, which I downloaded as part of package of his mods for 1.5, takes between 17 and 18 seconds to reload. rahter than 2 seconds as he indicates. I confirmed it on my FULL SIZE stop watch. And, my source of relief, the CaptainsGirls, GirlsInEveryPort, and Captain'sDeskPhotos mods do not show anyone, yet alone, women. Oh yea, that and a destroyer that has a sonar man who never sleeps, and is on my ass, makes this sim something, but I am not sure what.

Yeah, I had a bit of a snafu with the 'mini chron' mod. The first time I loaded it I had to reinstall the game. The second time (because I forgot which mod had the problem) I got lucky and only had to take it out of the mods folder. I would love to have a smaller Chrono but I'm not going to chance the mod unless there's a certified fix.
This has been a very good read so far, I'm learning a lot.
Cheers and Happy Hunting:salute:
D40

[commandosolo2009]

Greetings all,
I am trying to get my head around manual targeting and am currently reading Dick O'kanes' Clear the Bridge (very good read too by the way).

I started out using "the Dick O'kane' method as tutorialized (don't know if that's a real word but I'm going with it) by Rockin Robbins. I understand this method and have had some success with it - set up at 90 degrees to target track, offset aiming device 10, fire as desired points cross crosshairs etc etc.

However, every attack I read about in Dick O'kanes' book goes something like this (after the initial setup) "Constant bearing - mark!"
"Set!"
"Fire!" and the first torpedo went for her big stack aft. The next fish went for her middle, and the third forward.

What I don't understand is if he is firing as the target moves across his periscope crosshair, how does he shoot aft to fwd? This implies that he in fact does not hold his scope on a pre-determined bearing to fire but rather tracks with the target from aft to fwd?

I must be missing something basic here... calling Rockin Robbins to the bridge!
p.s. I tried to find the original Dick O'kane thread to post this to but failed miserably there also :-?


Just a quick question, you refer to Richard O'kane? or Dick O'kane? cuz as far as I've learnt Rich is the USS Tang skipper, while Dick is a member on Subsim famous for the sonar tutorial and other work here. Maybe he's set salvo to Left side of the periscope? thats the most possible explanation, or maybe the camera was on the other side of the ship, that could be apparent visual error. Of course I maybe wrong..

[ETR3(SS)]

Just a quick question, you refer to Richard O'kane? or Dick O'kane? cuz as far as I've learnt Rich is the USS Tang skipper, while Dick is a member on Subsim famous for the sonar tutorial and other work here. Maybe he's set salvo to Left side of the periscope? thats the most possible explanation, or maybe the camera was on the other side of the ship, that could be apparent visual error. Of course I maybe wrong..Dick is a nickname for Richard, so they are the same man. Although the man is deceased and not aware of Subsim ever.

[Rockin Robbins]

When aaroblood, gutted and myself cobbled together the procedure we were inspired by Morton and O'Kane's mastery of the TDC and their inventive use of it in their attack strategies. But they left no precise set of instructions because they hadn't thought there would be a bunch of crazy people (us) using a fancy computer simulator to model World War II submarines.

After aaronblood and gutted drummed the principles of a U-Boat attack into my feeble brain, it was my job to adapt that to the unique qualities of the Silent Hunter 4 American TDC, which I did. We had discussions about what name to use and finally decided to name it after a famous US sub skipper of the war. Since Dick O'Kane's genius was the inspiration and historical justification for using a constant bearing technique with an American submarine, we named the method after him. We have never claimed that this is an imitation of any attack that Dick O'Kane ever made. It is only named in honor of him.

[Liberatus]

Pisces:

Could you describe will look like an attack on a ship from a distance of 3000 m, which moves at a speed of 10 knots and I'm set for the course at 90 degrees? Of course using the dick O'Kane method.Please. I'll be very grateful:yeah:. Sorry for my english

[Pisces]

Pisces:

Could you describe will look like an attack on a ship from a distance of 3000 m, which moves at a speed of 10 knots and I'm set for the course at 90 degrees? Of course using the dick O'Kane method.Please. I'll be very grateful:yeah:. Sorry for my englishI'm sorry, your message doesn't make much sense. From what I understand of it, it seems I already did just that. With an example ship of 95 yards length. If your ship happens to be 95 meters then it's the same.

[Rockin Robbins]

Another thing that bears explanation is the reason that Dick O'Kane chose the stern/MOT/bow order of his spread instead of just shooting bow/MOT/stern as the target crossed the wire.

When you shoot bow/MOT/stern as I show in the Dick O'Kane tutorials, all three torpedoes follow the same track to the target, following in each other's wakes. This is called a longitudinal spread. There's nothing wrong with that, and it works well.

Until the target sees the torpedoes! Then a course change may allow him to avoid one of the torpedoes. Since they all follow the same path, avoiding one is avoiding them all.

This becomes critically important when firing from ahead of the target, as in the John P Comwell method. The easy fix for the target is to turn into the torpedoes and let them pass harmlessly to port. Try it in smooth water in the daytime. They'll avoid just about every time! You'll see the target turn into the torpedoes if they are approaching from forward of the bow and turn away if they approach from aft of the bow.

BUT if you instead shoot stern/MOT/bow, you're going to have to do some extra work. But that order results in the most divergent of torpedo paths. No longer do they follow each other in a straight line, but each takes its own path to the target and when shot in this order, stern/MOT/bow, their paths are separated to the maximum extent possible.

That means that avoiding one torpedo does not avoid the other two. The solution is MUCH more tolerant to possible reaction on the part of the target and your odds of a hit are much higher.

Using any method in smooth water during daylight it is critical that you shoot from such a range that the target cannot avoid your shots if they see the torpedoes approaching. That means that 1000 yards is the maximum I would attempt in those conditions, and my ideal would be 500 to 700 yards, just long enough for the torpedoes to arm. At that distance the target can gawk at the torpedoes and do anything he wants. He's dead meat.

[commandosolo2009]

Dick is a nickname for Richard, so they are the same man. Although the man is deceased and not aware of Subsim ever.

My bad mate!!:salute:

[I'm goin' down]

:har: That was good!!

Yeah, I had a bit of a snafu with the 'mini chron' mod. The first time I loaded it I had to reinstall the game. The second time (because I forgot which mod had the problem) I got lucky and only had to take it out of the mods folder. I would love to have a smaller Chrono but I'm not going to chance the mod unless there's a certified fix.
This has been a very good read so far, I'm learning a lot.
Cheers and Happy Hunting:salute:
D40

Dogfish, I stumbled upon your post yesterday. The posts you refer to are from November 29, 2008! A mere 25+ months ago. No one can say you failed to read the thread.

[Pitts2112]

Hello, everyone! I'm new here and have been playing SH4 for a few weeks. I played SH1 about 13 years ago and now remember why I played it so much.

I'm just now reading O'Kane's "Wahoo" and he described his attack method, which he and Morton developed together, as giving the enemy ship almost nowhere to go regardless of his maneuvering after seeing the incoming torpedoes. In reference to RR's recent post, RR explained the reasons for O'Kane's order of the torpedo/target points perfectly. O'Kane worked from middle to stern to bow, in that order, on most of the attacks he described in the book.

What I haven't been able to figure out quite well is how he moved his aiming point. I'm guessing he set up the whole attack for the first torpedo and held this bearing until the middle of the ship crossed the periscope hair, then moved the periscope to some point ahead of the first one, reset it in the TDC, then waited for the stern to cross that line, then moved ahead again to a third bearing, reset it in the TDC, and waited for the bow to cross the hair then. As RR says, that will result in three very divergent tracks, which give the enemy skipper no options that will avoid all the shots. O'Kane described pulling this kind of attack, and having all three shots out of the tubes in about 20-30 seconds. That seems to be enough time to reset new bearings for each of the target points on the ship, but that's just a guess.

The other thing he mentioned is that Morton favored a 120 degree setup with the above procedure, and that seems to be the key in the "no avoiding options" factor on this method, but I haven't been able to picture in my mind exactly what he means by that. I'm guessing he means firing from 30 degrees abaft the midships point on the enemy target, but i'm not sure about that or how that would be better than a straight 90 degree setup.

And if I understand how this method uses the technology onboard, the TDC is still giving gyro angles to the torpedoes that factor in speed and angle on the bow of the target but, since the bearing is fixed, the PK is not updating the position of the ship. In effect, it's tricking the PK by saying that the target is at the shooting bearing before it's actually arrived there and just holding off on the shoot until it does arrive. True?

And, finally, I saw someone earlier in this post someone talk about calculating AoB or eyeballing it. O'Kane was an expert at eyeballing it (as has been mentioned in other threads here), and doing so would be a good back-check that the visual, plot, and TDC data are all matching before shooting, meaning all the data input so far has led to an accurate solution inside the boat that matches what the skipper is seeing on the surface. I've not read anywhere of a plotted AoB being used as credible attack data. I think they were always eyeballed by the attack officer.

The amount of info on here is terrific and as added an enourmous amount to my enjoyment of the game. Thanks to everyone here for that!

Just .02 worth from a noob.

[I'm goin' down]

Welcome aboard skipper. You will be well served here. Yours was a very thoughtful, well articulated post. I am looking forward to the responses.

[Nisgeis]

Welcome aboard Pitts! Well, as I understand it, O'Kane set up the shot and then fired when the juicy parts 'passed the wire' e.g. the aiming mark on the periscope, so that would suggest Bow, MOT, Stern as the firing order. I don't remember him setting up for a different firing order. Have you got a page number for him doing that? It's been a while since I read either of those books.


The other thing he mentioned is that Morton favored a 120 degree setup with the above procedure<SNIP>

120 degrees of what though? 120 degree torpedo track angle? That would be fired from behind yes.

And if I understand how this method uses the technology onboard, the TDC is still giving gyro angles to the torpedoes that factor in speed and angle on the bow of the target but, since the bearing is fixed, the PK is not updating the position of the ship. In effect, it's tricking the PK by saying that the target is at the shooting bearing before it's actually arrived there and just holding off on the shoot until it does arrive. True?

Right, imagine everything is entered for the current target and it's all checked out with subsequent observations and the PK is running. What you do is move the periscope forward of the target and then tell the TDC operator to 'match' bearing. The TDC operator then moves the target bearing forward to match your aiming point. What this does is to advance the theorhetical TDC target along the ship's track, to a point where it would actuallt be if it had suddenly leapt forward along its own track. This makes the TDC adjust the range and the AoB of thetheorhetical target to what it should be for the target at that point. Now the TDC operator has to very carefully turn the target ship bearing input crank backwards so that the relative target bearing shown on the TDC does not move.

That's the key part really. What the TDC operated in this way what it is doing is continuously calculating the gyro angle for a torpedo to hit the spot at which the target's track and the aiming bearing intercept (if that spot was moving at the target's speed). This point moves continuously forward along the target's track, but less fast than the target moves along it. As you are calculating the intercept point between your periscope bearing and the track, when the part of the ship you want to hit arrives there as well, then you just fire a torpedo and it will hit that part of the ship. As the TDC is still running, it takes care of the range changes. The AoB will stay the same and as the speed is all entered in, the angle solver will provide the correct amount of advance to hit a moving target.

[I'm goin' down]

also see posts 18-20, supra, by Nisgeis.

Nisgeis developed the radar fix mod this year. You might want to check it out after you have satisfied your curiosity with the O'Kane method.

[Pitts2112]

Thanks for the welcome, guys!

Nisgeis, you've caused me to go back into "Wahoo" and read for more detail. What I've discovered is that O'Kane did seem to have favored working stern to bow, though not always, and seldom did he shoot from bow to stern. This implies he was shifting his point of aim for each shot. And that makes sense, now that I think about it because if he worked from bow to stern, and simply held the bearing fixed for all shots, then the torpedoes would have all gone down the same track, giving no spread at all.

He does also make mention of the TDC operator "holding the bearing steady" which implies he was doing something to the TDC, maybe that it wouldn't do on it's own, or had shut off the PK. I don't know how the TDC operated well enough to truly understand that passage, though.

To whit:
Page 137, the attack in Wewak harbor, their first attack on a destroyer was stern, midships, bow, in that order. The next attack was the famous "down the throat" shot on another destroyer, so doesn't really apply (but, man, what balls those guys had!).

Page 148, they attacked two freighters, working both from aft forward to hit their masts (main first, foremast second).

Page 261, he again worked from stern forward on another freighter with two torpedoes.

Page 263, this must be the one that stuck out in my mind, because he distinctly worked back and forth, aiming for midships first, mainmast, then foremast, so starting in the middle, shifting point of aim aft, the shifting again the length of the ship to hit foward.

Page 157, a freighter and tanker, again working from aft forward with three torpedoes at stern, midships, and bow on the first target, the tanker. On the second tanker, he again worked aft forward with two torpedoes at midships and bow.

Those are all I looked up but are certainly not all the kills O'Kane and Morton made in Wahoo. Looking them up was actually pretty easy. All you have to do is scan the pages for the words "Anytime, Dick", as those were Morton's words to O'Kane, on every attack, that is was OK to shoot.

And now that I think about it, Morton always seemed to give O'Kane the green light to fire when O'Kane announced a 90 degree AoB, which means all the torpedoes would be chasing the ship slightly from behind. This is possibly how he acheived the 120 degree attack, which had the added benefit of not putting a 90 degree hit on the exploder so he got fewer duds (?).

I really wish these guys were still around to answer questions as to what they were really doing and why it worked so well. Fascinating stuff, this.

Cheers!

[Nisgeis]

Thanks for the welcome, guys!

Nisgeis, you've caused me to go back into "Wahoo" and read for more detail. What I've discovered is that O'Kane did seem to have favored working stern to bow, though not always, and seldom did he shoot from bow to stern. This implies he was shifting his point of aim for each shot. And that makes sense, now that I think about it because if he worked from bow to stern, and simply held the bearing fixed for all shots, then the torpedoes would have all gone down the same track, giving no spread at all.

Yeah you're right. I think it's been too long since I read it - perhaps time to read it again. To shoot multiple times he just selects a point ahead of his aiming point, places the scope wire there, matches the bearing on the TDC and then fires when the desired part of the ship touches the wire. It's a minimal amount of effort as the TDC does all the work for you.

He does also make mention of the TDC operator "holding the bearing steady" which implies he was doing something to the TDC, maybe that it wouldn't do on it's own, or had shut off the PK. I don't know how the TDC operated well enough to truly understand that passage, though.

The PK wouldn't have been shut off, as that's a prime piece of technology there. The key is holding the bearing steady, which means the TDC operator winding it back at the same rate that it advances to hold it steady at the same angle that the periscope was pointed at. Then you know your shot will hit the part the wire is touching (assuming your solution is correct).

[Rockin Robbins]

Yes, actually, as Nisgeis and I had quite a long conversation about quite awhile back, there is an optimal torpedo track angle for maximum error absorption of observational errors and which makes it less possible for the target to maneuver away. He shot me this graph and asked what it means.

http://i196.photobucket.com/albums/aa293/RockinRobbins13/Silent%20Hunter%204/screenshot77.jpg

It shows the optimal torpedo track angle for a fast Mark 14. You see that angle increases slightly with target speed, but nowhere is it close to 120º. The most it gets to is just over 110º.

Anyway, we were trying to figure out just what the crazy thing was trying to tell us. After all, we can't enter TTA into the TDC and do anything with it. So I reverse engineered the whole thing and after all the fancy math, curses and the smoke cleared, I was left with one simple rule of thumb that explained the entire graph.

Fire when the AoB is 90. Then the TDC automatically calculates the lead angle, which is (of course) larger as the target speed is faster, yielding the TTAs in the stupid incomprehensible graph!

The truth is, you don't have to even think about torpedo track angle. It is simply a product of firing at the correct time. Why couldn't the US military have explained it that way?:D

Note that the chart specifies a zero gyro angle. In practice, anything under 20º is considered straight fire and will have no consequences, so you don't need to worry too much about that. If you attack at 90º to the target track as in the Dick O'Kane method, you're close enough for horseshoes, hand grenades and thermonuclear devices. If you just like worrying the process to death, you could attack from 110º.

[commandosolo2009]

The periscope reticle has markings in degrees that show where the various components are located. So you can see that the bow, middle, and stern compartments are located at 3 degrees left, dead ahead, and 3 degrees right. Then you use the offset feature in the TDC to aim the torpedoes at those locations on the ship.

I don't believe the "Dick O'Kane" method posted on the Subsim forums is historically accurate. Dick O'Kane, trained as a wartime US submarine skipper, would have used all of the features of the TDC and position keeper as originally designed, instead of the shortcut method posted here.

He did! And in the entire book, the TDC he used was to generate a range and bearing, (ie to check the accuracy of input) since he had to water-lap and dunk the scope alot of times, in order to not risk being spotted. He extensively used it at Honshu (fourth chapter and patrol)

[Rockin Robbins]

There is no evidence that Dick O'Kane ever used the Subsim Dick O'Kane method exactly as taught. As a master of the TDC he would have been intimately familiar with constant bearing attacks and would have used them.

Because of differences in how the game TDC works and the actual TDC it is not possible for us to replicate Dick O'Kane's practice. And when those of us who applied constant bearing techniques to the game TDC and came up with the attack method did it, we knew that Dick O'Kane had nothing to do with the technique.

In order to make our techniques memorable we chose to name them after prominent US Submarine Captains: hence the Dick O'Kane Technique and the John P Cromwell Technique.

These attack methods are historically feasible, meaning they could have been performed with the instruments and knowledge of the time. They cannot be shown to be precisely applied by anyone during the course of the war.

So you can do a game Dick O'Kane attack in a real submarine but you cannot use Captain O'Kane's method in Silent Hunter 4. Our game TDC will not allow it.

[XLjedi]

He did! And in the entire book, the TDC he used was to generate a range and bearing, (ie to check the accuracy of input) since he had to water-lap and dunk the scope alot of times, in order to not risk being spotted. He extensively used it at Honshu (fourth chapter and patrol)

So what exactly is the issue? :06:

There was a page in O'Kane's book I was trying to mimic where he was overriding the position keeper and holding the bearing to target constant. I could find it if I have to (I know I've quoted the page number here before); but I'd have to check his book out again from the library. I don't think anyone is suggesting the guy didn't know how to use the TDC as it was intended.

Frankly, I was trying to intitiate a Fast-90 attack in a US fleetboat, but the PK/TDC doesn't allow for adjusting the AoB while panning the scope (aggravating). I noticed that O'Kane could do something with his TDC that I couldn't do in the game and that irritated me a little. ...did my best with what the PK/TDC allows in this game and this method sorta fell out of it. This game models a position keeper PK and TDC as if they are forever joined, whereas I think the full contraption in the fleetboat had both a PK and a TDC and they could somehow be operated seperately, but I don't know that for sure, I just suspect it was the case from what I read of O'Kane giving various commands.

I didn't really have any idea what to call the technique, except that Fast-90 seemed inappropriate because the TDC doesn't have the same whiz-wheel qualities of the U-boat TDC. RR came up with the idea to give the nod to O'Kane... seemed OK to me, and less heady than calling it the RR or AB technique. I mean I guess if I were to try to accurately classify it, I'd call it the "No TDC" method. You're basically disabling the TDC and pointing the nose of the sub where you want the torp to go. Not quite as fun as what you can do in the u-boat but it gets the job done.

Incidentally, I recall reading that the fleetboat PK/TDC seemed to be an adaptation of a battleship targeting computer. My take on the u-boat vs. fleetboat method of targetting is that it seems to be oriented to the types of attacks. The US fleetboat seems better equiped for single target tracking and stealthy ambush, complete obliteration of single target. While the u-boat seems better equipped for setting a generic course for lots of ships (convoys) and then popping up and unleashing hell on several targets quickly.

I like em both. :ping:

[XLjedi]

:hmmm: Ummm...

I would like to go on record once again to mention that when I first described and tried to mimic O'Kane's tactics. I did in fact use the TDC as I believe O'Kane did and it has always been somewhat a thorn in my side that it was dumbed down over time but kept the "O'Kane" monicker.

What people call the O'Kane method now is such a crude method it doesn't really do O'Kane justice. :nope:
http://www.subsim.com/radioroom/showpost.php?p=627351&postcount=134

...where I mentioned "develop a solution for a 20° bearing (70° AoB)" I was using the TDC to do it.


In his book, O'Kane did the same thing as I described in the above post... holding the aiming wire constant and firing as target points passed the wire. It was just one attack that he documented in his book, doesn't necessarily mean he always did it.

[CDR Resser]

If I may add something to the discussion about the 120 degree reference. After spending many years reading O'Kane's books, I finally found out what was meant by the 120 degree track in another of the books about both Morton and O'Kane, I believe by Tuohy. O'Kane himself mentions it only in passing in each of his books.
The 120 degree track refers to torpedoes being fired to approach the target ship aft of the beam, or 120 degrees off the bow. This aspect allowed a spread of torpedoes to cover almost any evasive maneuver that the target might make.
It was always rather difficult to imagine this before I was able to demonstrate it using the game.
Hope this helps, and I am not repeating anything already covered.

Respectfully Submitted;
CDR Resser

[TorpX]

:hmmm: Ummm...

I would like to go on record once again to mention that when I first described and tried to mimic O'Kane's tactics. I did in fact use the TDC as I believe O'Kane did and it has always been somewhat a thorn in my side that it was dumbed down over time but kept the "O'Kane" monicker.

What people call the O'Kane method now is such a crude method it doesn't really do O'Kane justice. :nope:
http://www.subsim.com/radioroom/showpost.php?p=627351&postcount=134

...where I mentioned "develop a solution for a 20° bearing (70° AoB)" I was using the TDC to do it.


In his book, O'Kane did the same thing as I described in the above post... holding the aiming wire constant and firing as target points passed the wire. It was just one attack that he documented in his book, doesn't necessarily mean he always did it.

I'm glad you posted this. It tends to be confusing when people see the "O'Kane method" and try to replicate exactly what was in the book. In the future it might be better to name techniques descripively rather than after historical figures, (i.e. The Perpendicular Attack method rather than The Jimmy Johnson Fleetboat Ace method). Many will see the most recent posts or the tutorials, but not read the hundreds of posts in the various threads.

[Thrair]

I need to try this type of shot at some point. Trouble is I've gotten very used to a method I use (mostly continuous bearing, but with some manual tweaking of the numbers), and am a little wary about shaking things up when I've a system that works very well for me.

On the other hand, learning new tricks will always be handy. Perhaps next time I go on a SH4 binge I'll try it out. Lately, I've been playing World of Tanks pretty heavily, and any time I play SH4 atm, it's to just hop in for a quick patrol. (heh, "quick patrol".... when do those ever happen? :P)

[Rockin Robbins]

Frankly, I was trying to intitiate a Fast-90 attack in a US fleetboat,

There you go, right there! And that was the conversation that resulted in what we teach as the Dick O'Kane Targeting Method. It is named in honor od Dick O'Kane but has NOTHING to do with the mechanics of how O'Kane the person shot torpedoes. There is perfect evidence that he did constant bearing shooting. I think Nisgeis has gone as far as we can to determine what the mechanics were. Lacking the ability to "very carefully turn the target ship bearing input crank backwards so that the relative target bearing shown on the TDC does not move." as Nisgeis explains, we have to find historically plausible but not historically used methods of achieving most of the same result.

We achieved the booms. We did not preserve the use of the position keeper to validate our solution. Since our initial aim was to use the US TDC to replicate the U-Boat fast-90 attack as much as possible, we didn't feel we needed to go any further.

Yes, the Dick O'Kane technique could be extended to include other angles of attack than submarine 90º to target track with the introduction of complexity. However Nisgeis covered that perfectly with his Vector Analysis Technique.

That's where my personal goal of making successful captains out of newbie captains came in and I eliminated all steps that did not directly contribute to the boom. Aaronblood is right that using my rules of thumb can obscure understanding of the general concepts behind torpedo targeting.

But I figured that your next step is to wrap your brain around normal US targeting techniques, and you would understand it then anyway. My goal was to produce reliable manual targeting booms as quickly as possible for a newer player.

Limited goals plus ruthlessly simplified procedure plus application equals success. It's simple addition!http://i196.photobucket.com/albums/aa293/RockinRobbins13/smileys/apple2.gif