Stumbled across this thread just now and thought it might merit a bump after RFB 1.52

After four patrols in early 1943 I have come to develop my own attack technique by trial and error. Maybe it is of interest here (being a constant bearing technique at 50-60 degrees)

One of the best ways to prevent duds is by having the torpedoes hit the target at an angle around 60-70 degrees, so the Dick 'O Kane technique results in a lot of duds for me with the perfect 90 degree shots.

the biggest problem with getting a perfect solution at removed angles is that your boat moves during the setup. thus, a perfect solution at 1500 yards on a bearing of 330 will have turned into an unaccurate shot by the time the target gets there (as observed in the original dick 'o kane video I believe, when the boat drifted a bit after cutting the engines) keeping in mind that realistic gameplay calls for continued propulsion to maintain depth, this becomes undesirable

To solve this problem, you can aim the boat so that the angle on the bow will be 60 degrees starboard at your zero bearing. At a target speed around 10 knots, this results in a shot at several degrees starboard angle off your bow, which is still good enough for me. The greatest advantage being that your solution will stay accurate even if you get the range wrong by several hundred yards by slowly creeping up on the target's course line after inputting the solution

still with me?

It's basically still the same constant bearing setup, for a shot at zero bearing (with the torpedo making a tiny turn to starboard) while the entire boat is not on a nice 90 degrees to the target but rather a dud-preventing 60 degrees to the target.

Personally, I find this an excellent way to get some tonnage in the log, even with the early war duds.

If this is all one big unclear mess, I'll provide some screenies :)

Works perfectly for me. If you use the vector analysis from the video, which you can do in-game right on the chart, you can calculate the correct lead angle for any angle to the track. Then you can throw the TDC overboard (saves weight for more food!) and go to town!

It does mean that you have to know the torpedo's speed, but that's a minor difficulty compared to the flexibility you get.

ooohhh just watched the vid (nice one btw, liked the taskswitching and drunken sailor bits :p )
the vector analysis is a new one for me, i'll give it a try on my next contact

but what i was trying to say is this: if you set up the shot on a bearing of 349 at point A, for an aob of 34

it won't be aob 34 on bearing 349 at point B, 1000 yards ahead of point A. right?

argh all this algebra makes my head hurt. i'll play the game and draw some lines, then i'll probably end up coming back here and saying something like 'excuse my utter stupidity'

meanwhile my above mentioned targeting at 0 bearing on 60 degree shots is very satisfying though :)

edit: erm although the vector analysis would suggest that the angles will stay exactly the same while the range decreases, as they all converge at the same point of BOOM

oh *insert random profanity*

You are obviously correct
i made a very silly mistake: the dot on the map where the target course intersects with the 349 mark on the bearing ring DOES change as you creep closer to the course...
but so does your distance to the target and thus, the angles stay the same, whether you are at 2000 or 500 yards out.
as such, range never even enters into the equasing, except for drawing the plot and putting a random number into the tdc to set the bearing

in fact, shooting at zero bearing means the torpedo has to make a tighter turn at closer ranges (because the turn starts after the torpedo goes underway, leaving less room to properly make the turn) so if anything, it is the zero bearing shot which will get less accurate as you drift closer

firing by vectored lead angle is a gem! I always just took a wild guess, being satisfied with anything between 350 and 10. But now I noticed my attackplot showing a perfect straight line for the torpedo, along the the zero bearing line. torpedo gyro angle is exactly 0 at any range.

if you can forgive a poor fool for opening his mouth, I'll just move on and sink some ships.
After this load of nonsense my addition to this topic can be summed up with:
'60 degrees is also nice'

Actually, think of it this way. What is AoB? It is nothing but your bearing from the target. So unless you are on a collision course the AoB will change as time goes by. That's why we use the position keeper. It keeps the bearing and AoB updated all the time. You can see this really clearly in the Dick O'Kane attack. When he's a long way away, he's looking maybe 10º from his bow to see you. That's an AoB of 10º. But just before he gets creamed by the torpedo he's looking almost perfectly abeam to see you 90º from the bow, an AoB of 90º. See how easy it is when you change your point of view?

So why doesn't the vector analysis show this? You're going to need a drink. Maybe several drinks.... The vector analysis is done from the point of view of the torpedo, not your sub. The angles all stay the same for the torpedo from the moment you fire to the moment of BOOM. That's because it is supposed to be on a collision course!:up:

before i wander off to look for that drink...

http://img396.imageshack.us/img396/2860/angleskn6.jpg
http://img396.imageshack.us/img396/a...pg/1/w1024.png

i imagined a target with course 60 speed 12, the vector in the top right corner shows me that for a 46 knot torpede, the lead angle is exactly 12 degrees

so i made a plot at around 1100 yards, moved forward a bit and made a plot at 700 yards. what i tried to show is that the point where the target is when you launch the shot varies between both plots, which is why i thought that drifting away would make the solution inaccurate. (which is why i always shoot at a zero bearing plot, resulting in a 12 degree gyro angle for the fish)

but doing the plots in the below screenshot, i found that the angles stay exactly the same. obviously, because the target is closer to the impact point when you launch at closer range, but the torpedo has to travel less far as well,

http://img89.imageshack.us/img89/1885/angles2ub6.jpg
http://img89.imageshack.us/img89/ang...pg/1/w1024.png

so yes the colision stays the same, regardless of range. my mistake
(i think we're both saying the same here, but i wanted to show what i learned just now)

edit: yes we are saying the same. '4600 yards against 1200 yards' amounts to the same as '46 yards against 12 yards', so the vectors (point of view from the torpedo) never change indeed

im gonna get that drink now and use that vector thing for real

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

Aaronblood is laughing at us. Numbers are like cotton candy to him. I think he BREATHES numbers in his sleep. At will, he can make me look like the idiot I am. I'm just a communicator, not a numbers guy. I can eventually make sense out of them, but numbers are aaronblood's native language.:up:

This is based on the principle of similar triangles. It says that a triangle with the same interior angles will grow/shrink in proportion. This is true for any triangle.

http://education.yahoo.com/homework_...266-5-pr-q.gif

You can see that the triangles QRP and UVP are similar. It doesn't matter if the target is at Q or U, if it is travelling along the line to R or V, the torpedo will connect. The target could be anywhere along the line QP (or beyond Q) and the torpedo in this picture will connect as long as the torpedo is launched at P toward R. Note that the targets at Q and U are traveling at the same speed and same direction.

Also note that this picture doesn't describe what the sub itself is doing (in terms of speed or direction). This picture just describes the torpedo and target tracks.

well, quite :know:

Starbird, I believe that's what would be called a classically elegant illustration.:up:

Edit..Crap, When I posted this, I didn't realize there were two more pages of this thread I had not read yet!:o

There have been pros and cons for this method stated here. One of the pros I did not hear mentioned is that with this technique, the range you fire from would be increased (over the O'Kane method) and therefore, the ability to be detected by the enemy will be slightly decreased or possibly delayed.

The "O'Kane" method is by far my favorite and as long as the following criteria are met, it's damn near impossible to miss: (1) You have accurately calculated (not estimated) speed (2) The target holds that speed and course.......

As for the above criteria, I find that if I achieve both, I can hit exactly where I aim from very long ranges, but it is very important to nail the speed to within a 1/4 knot. Some will say that's getting picky, but if you are firing from 3500 yds, that type of accuracy in speed is needed and will make the difference between a hit or miss.

Now as for number 2 of the criteria, I have many a time been in perfect position on a DD from about 3500 yards using the "O'kane" setup and painstakingly calculated the speed, only to be detected about the time I'm ready to fire. Therefore, I'm very interested to try this new tecnique on those DD's to see if it aids this circumstance by the ability to fire sooner and a little further away. I'm awaiting the formula and/or the video!

Yes Blackbob, your guess is right. I don't remember for sure, but I remember the measurements being in knots only up until a certain patch (I beleive 1.4), so patch up to fix that issue.

That could be it, or it could be your scale. Not sure, but if you are not zoomed in close, then your scales may be in miles. Certainly if you measure over 10,000 yards, the readout on the ruler or divider will switch to miles, but you'd have to be measuring over 5 miles for that to be the case. The increments will then be in 0.1 of a mile.

How do you input speeds of less than 1 knot? The readout is only graduated in whole knots unless there is a mod I'm missing.

Urge

I have just finished a several hours session practicing O'Kane's and Cromwell's techniques from watching Rick's movies. And i have to say they work like a charm every single time. Vector analysis is really fun doing during the game, i also noticed that certain values never change during these calculations however i also double check by drawing an analysis on the same course of the target. Just abit further away of its non-existence course (since it will be dead by then hopefully :))

On this attack, i launched four fish, all of them hit DEAD ON where the wire was when launched. Nothing beats that.

Speed calcs:
http://www.chimigag.co.il/Images/speedcalc.PNG

Attack plan:
http://www.chimigag.co.il/Images/attackplan.PNG


I have run into several misses when a veteran crew aboard destroyers noticed the fishes tail but in 99% i've had a successful hit in an unprecedent precision.

Thanks alot for sharing this information, these 2 techniques are now by far my most favorite for easy tonnage and without going through the hazardous PK and stadimeter readings.

Update: I tried this method last night with great success. Just as I was saying above, I ran into a task force of two DDs. I was able to take out the lead and due to the increased closure rate, by the time he saw the fish it was too late. Also, due to the capability to fire from a longer range, I managed to remain undetected. Of course, the second one turned my direction and I managed to put him under with a down the throat shot. It worked just as I had hoped.

This leaves me to ponder:hmm: , and therefore, a question....Will this method work with any angle calculated other than 45 degrees ? It seems it should, and I'd like to try from say, 25 degrees. In my scenario above, this (may) would enable the ability to fire on the second target shortly after the first. That would avoid the sometimes risky "down the throat" shot. I'll try it later and report my findings.

Yes it will work, as long as your gyro angles are still zero.

Grrr!
 

What the hell am I doing up at 3:45 a.m. reading about the Cromwell attack? I think it is time to see a shrink...after I watch the video tutorial first thing in the morning after I get up.:dead:

Did not work
 

I set up a Cromwell attack. The ship was approaching from my port side -- the target's starboard side. I set up at a 45 degree angle, and checked it with the bearing tool to make sure my zero bearing was at a 45 degree to the target's track. I checked the speed of the target over a 3 minute interval. I set the scope at 10 degrees and turned off the PK. I sent the range to the TDC. As the target passed the cross-hairs, I fired 4 shots along its length. The torpedoes were set for 20 feet, within the target's depth. I set the AOB at 35 degrees starboard. All of the shots missed. I must have had the speed wrong? Any other ideas? I was set up for so long that I consumed three of RR's Mai Tai's, but I will save victory slice of cheescake for a later date.

Did you watch your fish with the external camera? They might have passed under the ship if you used contact influence (the torpedos had a defect where they ran deeper than they were set for). I generically set my torpedos for 13-14 ft for just about every merchant since I rarely identify a ship( I like to shoot from far away) and I find that I have a low % of torps that pass under.

Urge