I've run into it repeatedly. However referencing your diagram shows clearly that owncourse is entirely irrelevant to AoB.

All of these answers have been really helpful and that explanation by rockin robbins made it clearer than it has ever been to me. I just want to know few more things. Do you need to send the bearing individually of range or is the bearing automatic? Also when using radar or hydrophone to send information to tdc, does it update the tdc dials or is it just inputing the info without any kind of acknowledgement? When I click send range from hydrophone to TDC, i can never tell that it has actually done it. Of course, if there is already an explanation as clear as the one in this thread about it, please point me in the right direction, the overall theory behind all the variables effects on targeting is interesting and helpful.

For Mallet (in particular) The following is much simpler to learn as a newbie, then you can explore the PK/AOB/sonar/radar complexity AFTER you are more familiar with the simulation:

With regards to using the TDC in all its complexity, (especially with the PK usage), I find that complexity for the sake of necessity in a game can be fun, however, even Dick O'Kane used a much less complicated modified constant bearing method of torpedo fire control that was much simpler and can be closely emulated in game. In fact Rockin Robbins himself has a video demo showing its simplicity. See here!

Utilizing this constant bearing method, you don't ever need to turn on the PK, let alone worry about intermittent AOB/range readings. In fact all you need to start is initial course and speed so you can plot an end around if necessary to position yourself right off that course. Of course a few intermittent observations are necessary to verity that the target is indeed continuing along that course with/without a zigzag. Work your way into an approx. 90 degree intercept point at your preferred range. I generally use 600, but sometimes as necessity dictates will increase the distance. I will not set up less than 600 due to torpedo arming distance.

With that in mind, and the approx. intercept point determined, you can preset the TDC with speed first, then preset what the predetermined AOB will be AT that intercept point. I use 10 degrees lead AOB for 8 knots or less, 15 degrees lead AOB for 9 to 12 knots, and 20 degrees lead AOB for any speed over 12 knots.

Then at this same time, I preset the scope/TBT to the same lead angle (10,15, or 20 degrees), basically looking straight down the same heading as the AOB lead angle. Keep in mind, the sub itself will be pointed at close to 90 degrees to the target track. After the normal double clicks on the TDC, you can determine that your setup is almost perpendicular to the target AND you can do a quick check on the attack map screen to see that the torpedo is set up to fire at the approx 90 degree intercept gyro angle you have set into the TDC.

Usually, I have the TDC already pre-setup WAY in advance of reaching the intercept point. This allows me to quickly make a simple one parameter change and re-double click if something necessitates a change. Keep in mind that you have to have the fore/aft torpedo selected that you are plotting to fire along with the scope/TBT lined up along the same lead angle. The latter two items can really mess with your mind when you re-double click and you have moved them since the last time you double clicked. Again this can be confirmed with the left side TDC ship image displays and a quick glance at the attack map screen.

All you have to do now is place yourself at the predetermined intercept point and wait for the target to cross the Periscope/TDC wire. In effect the target has placed itself on the pre-determined artificial target point without you having to make all sorts of bearing/range/AOB observation inputs to the TDC/PK referred to in the earlier post(s) above. I use this technique in almost all my intercepts because I figure if Dick O'Kane used this method it's good enough for me. Correct me if I'm wrong, but if you add up all the sunk tonnage he was responsible for (Wahoo AND Tang), he was probably the leading sub ace in WWII.


Some notes:

I try to ensure that the target will indeed be at or slightly outside the predetermined TDC range setting (especially at higher target speeds). The reason for this is at such close range and higher target speeds the TDC lead angle will cause a bow shot to actually cross in front of the target instead of intercepting the bow. This intercept range is adjusted preferably by a small judicious forward/reverse ship movement, but can be done on the TDC, (necessitating double-click rechecking of the solution of course).

Just because you have set up a solution waiting for the target to cross the wire does not mean you have to abandon the shot if you have managed to be a little late raising the scope all the way up. In that case, keep your calm, move the scope a little ahead of the target bow, double click the TDC and fire when he crosses the wire at that new point. This quick snap shot re-setup did not change any TDC settings except the periscope bearing it was fired on, so it usually works and for sure the target is probably slightly further from the pre-determined range referred to in the earlier note above.

This constant bearing technique is much more adaptable to quick snap-shot solutions when you are in the midst of a group of ships than the PK/AOB observations earlier discussed.

You can also use this constant bearing method at sub headings different than a 90 degree tangent, which is helpful in mult-ship convoy intercepts. You just point the sub at your chosen intercept angle and then set the AOB to (10, 15, or 20 degrees) lead from that and align the scope/TBT to that same lead angle. This allows you to shoot at a further target as it crosses the wire using a slower torpedo speed setting, then quickly resetting the TDC range to an inside target and firing torpedoes at a faster speed setting resulting in near simultaneous detonations. (This assumes all the convoy ships are on the same course and speed)

Remember the object of the game/simulation is to sink tonnage in as realistic (but not necessarily as complicated) a manner as possible, depending on your enjoyment factor of course.

Gary Lensman, I just tried that method and succeeded right away, quite amazing how fast that was. I have had some success in the past using the regular TDC system, range, AOB, Speed, and all that. However I just sometimes fail for a reason that I really cant find. The ocean was pretty wavy but my speed calculation and AOB was correct, but the bearing/ range just wasnt putting the artificial target over the actual target. I couldnt use the stadimeter as the waves obstructed my view so I used sonar instead. Perhaps my range and bearing was off somehow. I think I am getting better but my attempts at normal TDC usage are 40/60 success to failure.

In my experience any torpedo solution in seas resulting from winds over 12 meters/sec is likely to fail and even 10 meters/sec can be iffy. This is regardless of the solution accuracy. Seems the torpedo(s) don't like to cope with the rough water. I've had shots lined up as described above at 600 yards, the ship just crawling along at 5 knots and still no hit (not even duds). I have made it a note to self not to waste torpedo(s) if the wind is 12 knots or greater and unless I'm just desperate to use my last torpedo so I can head to the barn, I won't bother unless the wind is 9 meters/sec or less.

edit> The random weather model in this game is so screwed that I've seen times when a 15 meter/sec storm lasted for game weeks across most of the pacific, going from east to west north of the equator against the prevailing winds no less, much like the great Red spot on Jupiter LOL. Usually in those cases if I have not made a contact and the wind is stuck on 15 meters/sec (not 14 or less), I will just semi-rage quit and restart from the last save. Even then it might take several restarts until a restart results in a weather taper down. It's just so frustrating the amount of detail devoted to the game/simulation and then have to deal with totally illogical weather patterns that span half the Pacific or more in effect resulting in once in a 1000 year earth storms constantly. Yes I'm running a weather mod patch for TMO but all it seems to do is make the bad weather seas more realistic. It doesn't seem to do a darn thing about maxed out wind duration.

Don't quit in a rage, try the Ctrl-N cheat to immediately change the weather!!

Did not know that one... Thanks

Seriously, though, to me, the weather model in this game is the only thing seriously flawed enough to ruin the gameplay. I'm hoping that's one of the things addressed in Webster/Rockin Robbins new mod.

You know, that one wasn't even on the radar. But now it is!

Yes, people have asked "if the US submarine TDC was so all-fired sophisticated compared to the German one, why didn't they sink a lot more ships!"

Complexity results in errors. Sometimes complexity results in unquantifiable errors that can't be mitigated. The real Achilles Heel of the stadimeter measurement of range/bearing (yes, in the game, both are always sent together to the TDC when you press send) is that it absolutely depends on correct identification of the target. Most targets in the real war were identified WRONGLY. That will result in an error that can't be predicted or quanified. The secondary problem of the stadimeter is the difficulty of judging exactly where the tip of the mast is, or exactly where in that thick line is the waterline. A one-click error can be a significant number of yards. When combined, these two error sources are a barrel of laughs.

The Germans, and us if we use a constant bearing technique like the Dick O'Kane method, didn't give a rat's patootie about identifying a target except maybe for bragging purposes in the bar between cruises. Range didn't matter much to them because their targeting method only cared about the angle between target track and submarine course and the speed of the target. Get those two somewhere close, close the range to 600 meters and the target goes down.

Simplicity is the simplest way to eliminate error. Every step you can eliminate. Every calculation, every measurement you do not need to make adds to the accuracy of your shooting.

Can i ask why range doesn't factor in the Dick o'kane method? Kind of confuses me how you could pick any range and the torpedo wouldn't just turn way left to catch a target 10000 yards away versus 1000.

When your gyro angle is near zero (angles less than 20 degrees were called "straight shooting" by American manuals) then the lead angle does not change for a target traveling at the same speed on the same course regardless of range. That really sounds opaque and is hard to understand. Try this:

http://i196.photobucket.com/albums/a...psxu8lgs8h.gif

Now you can see that all you need to know is the shoot bearing. Sight down that bearing and when juicy parts of the target present themselves you pull the trigger. Each shot is aimed as a specific spot on the target. It doesn't matter what the range to the target is--you will hit your spot if the target speed and your angle to the track are correct. And that, gentlemen, is what made German U-boats and a select few American sub skippers including Dick O'Kane, so deadly. Simplify! Then simplify more.

Target identification? Who needs it! Stadimeter? What in blue blazes is that doing on my boat? Toss 'em out and lets sink some targets!

edit> RR beat me to it, LOL His small video is a great "perfect" situation example and gets the point across quite elegantly, however, in the real world the torpedo wakes of the first couple of torpedo(s) will most likely be seen traversing in front of the closest targets (unless of course you are using wakeless electric torpedos, gotta love those). That's one of the reasons I prefer the angular standoff shot... less chance of the wake being observed by the closer ships.

Just to clarify, in his (RR's) Dick O'Kane video he accomplishes the straight shot (zero gyro angle) by backing the TDC range setting down against the minimum range stop point.

Yes, where multiple ships are concerned you must make several deals with the devil to shoot several. The further away from 90 degrees from the track you get, the smaller chance for a hit and the less error tolerant the solution becomes. Furthermore, if you shoot from ahead of the track the ships are more apt to see the oncoming torpedoes and only need to turn a fraction of a right angle to turn into the oncoming torpedoes and make them miss.

Of course you can sit 90 degrees to the track and use Mark 18s--too slow and THAT reduces your chance of hits while keeping them from seeing the wake.

Dick O'Kane, and I agree totally, said that we get darned close, target ONE target at a time and put her on the bottom. Again, simplifying the process gives maximum success. Return and target another. Repeat until the escorts split for home because they have no merchies to herd.

Yes I've seen fancy videos of multiple ship targeting and they look cool. But in practice you'll come up empty more than bag two or three. One premature explosion with six torpedoes in the water targeting three ships and all three ships go crazy and you waste a great portion of Uncle Sam's money.

Dick O'Kane said that when you have to schlepp back 6000 miles for a torpedo refill you aim every shot and keep it simple. Limit the fancy stuff!:D:D:D

The actual weather graphic effects especially TMO's are quite OK, it's the weather duration timing that's the real problem, both directions, meaning it stays wind flat 0 way to long also, just as bad as pegged out 15 for game weeks.

Don't know if its possible but there needs to be a way of the weather generator algorithm or internal lookup charts to minimize the super long time maxing out. Doesn't matter if a maxed out effect suddenly turns the other way. That's somewhat realistic at the onset/trailing time of storms, but the only time a sub might have the possibility of the long term weather effects in game would be IF it was traveling in the same direction as the prevailing winds to/from it's base. I wouldn't even advocate for that in game either because it is the most boring part of the game traversing to/from the home base, no need to pester the gamer with a storm following him back from Japan to Midway

Generally, if I setup a multi-target solution, it will only be against 2 targets and of course to keep it simple they will be along the same line of sight using an angular vs perpendicular sub line-up and 10-15 AOB/Periscope lead from there, then almost always go deep and wait for the others to pass and perform an end around for a repeat on remainders.

If they are in line, I'll use slow setting torpedo(s) for the first ship, followed by fast setting torpedo(s) for the trailing second ship

If they are side by side, I'll use the fast setting torpedo for both targets as they cross the wire.

This is the part of the game simulation that I particularly enjoy, shooting, escort avoidance, and scooting, instead of immersing myself in all the stadimeter/AOB complications discussed earlier.

Morton/O'Kane did this for efficiency reasons, I do it for immersion enjoyment. LOL

What I enjoy is setting up my TDC by radar information half an hour before I maneuver the boat into position and shoot! The work is already done. All I do is verify and shoot. It really helps to keep the workload down and the situational awareness up.

That being said, I've been working on understanding the wrinkles of the stadimeter/conventional American submarine attack. I don't think it's been taught right yet and I want to make a video as clear and easy to understand as my Dick O'Kane, John P Cromwell and vector analysis videos. I want people not to just be robots, plugging in numbers for unknown reasons, but having a reason and a verification and a backup plan for everything.

I don't do it much, so I'm getting enough experience that I won't be an idiot about it.

After doing a little bit of mathematical mulling over the 90 degree Dick O'Kane attack, I figured out an equation that can be used to calculate the attack angle required.

Y = lead angle in degrees
X = target speed in knots
Z = torpedo speed in knots

Y = arctan(X/Z) * 57.3

Before you go and run away because this has trigonometry in it, the arctan operation does the same thing that we do when we connect our torp & target speed vectors tip to tail and measure the angle with a protractor. Arctan (or inverse tangent, they're two names for the exact same thing) spits out the angle measure (in radians, hence the multiplication by 57.3) of the angle that is opposite from leg X, and adjacent to leg Z.

Of course, using this equation without a calculator or trig sheet would be quite impractical, but I'd imagine that submariners back in the day had access to trig sheets.

In any case, this equation isn't terribly useful unless you are greater than about 2,500 yards from the target, where getting hits requires closing down on uncertainty as much as possible. For a closer in attack, RR's rules of thumb (10 degrees for slower than 15 kts, 20 degrees for greater than 15 kts) more then well enough do the job.

Tried this. using TMO/RSRDC. No Joy.

All I got was the "Yes, Sir, Sweeping" audio

Is there a particular MOD where this Ctrl-N has been redefined?

I believe you need to be on an outside view (bridge/deck gun/external camera) for it to work. That's been my experience, anyway.

Correct, sorry for leaving that out of my first reply. But, be careful, because if your visibility clears up, so does your targets!

Cool, I have a save right now a couple of game days back not deleted yet that has 15 meter/sec winds. I had managed to take out a Nippon Maru (10,000 ton) baby, (3 torps fired point blank 600 yards constant bearing approach, all 3 hit, one was a dud...) Took a while to go down, with an escort in the area, which I was deathly afraid was Bungo Pete (TMO/RSRDC) You're saying I gotta risk hell and high water just to use the Ctrl-N combo... Wow: LOL

I've since then advanced on purpose without waiting because 0100 I got an Ultra dispatch re:IJN heavies out of Truk headed to Tokyo and reaching a certain position in 3 days time, and I'm east near Bungo Suido. I would not use it in that situation since I consider that cheating myself out of the challenge of getting back over in position even in high seas and hoping for a little better weather somewhere along the way... it paid off, I'm gonna make it on time and the weather dropped to 9 meters/sec... doable for me if I can manage to be in front of them figuring them to be fast movers.