bothersome,
i like the 70/20, you have brought up a great point, this type of shooting can be done at any angle, i only did 8010 because i have been shooting this way for more than 5 years, and i know it like i know my backyard.

im working on the 70/20 for you, i will get an answer for you tonight, and also a tool that you will need to figure out torpedo intercept angles,
like the torpedo data i uploaded.
its called intercalc, made by david sandberg, its a great torpedo intercept calculator, real easy to use, youll see.
thanks for sticking with the concept, even if its not 8010, the great thing is, your thinking your own version, and thats cool.

Quoted yet again for emphasis.
Please please please please please answer the above question.

Seriously, greyrider, you are clueless, the answer is NOT 10. It can be ANY AOB that closes range. ANY. The AOB is independent of the bearing.

I did NOT say that the submarine was going to intercept the target at 90 degrees. You realize that you can intercept a target at some angle other than 90, right? You cannot be that clueless.

I'm beginning to think this guy actually believes that intercepts are by definition at 90 degrees.

His answer to my scenario proves without a doubt he doesn't understand the geometry at all.

No, the target can close, and the bearing stay the same, it's a matter of hat SPEED he is making and what AOB.

Your ENTIRE premise is based on the SHADOW of the target path on an infinite background. You are looking at an APPARENT motion, but not the ACTUAL motion.So the ship can be JUST closing, for example, say 1 degree of a parallel heading, and be moving just a fraction above the sub's 3 knots. It is STILL closing.

Look again at the diagram nisgeis posted and sergei just quoted. That tells you all you need to know.

In my example above, I made an error for calculating the AOB on the target.

Using the game and plotting lines and angles on the map, it is 17 degrees angle on the bow for:

80 degree bearing.
3 knot sub speed.
10 knot target speed.

But while I have it up. Let me give some other figures.

80 degree bearing, 4 knot sub speed, 10 knot target speed = 23 degree AOB.

80 degree bearing, 4 knot sub speed, 8 knot target speed = 30 degree AOB.

80 degree bearing, 2 knot sub speed, 8 knot target speed = 14 degree AOB.

80 degree bearing, 2 knot sub speed, 11 knot target speed = 10 degree AOB.

80 degree bearing, 3 knot sub speed, 11 knot target speed = 16 degree AOB.

As we see from a few samples from above, and I *think* this is what greyrider is trying to get at, is that when you have a target reported to you by your sonar man, that a target is going *medium* speed, then it becomes very useful information on building a window for AOB. This is a window small enough that shouldn't throw off the timing for the torpedoes to make a successful hit. This is with the 80 degree bearing approach. But as you decrease the bearing approach like in a 70 degree approach, then the window widens and opens more room for error. But on an 80 degree, it may be tolerable to shoot from the hip if you don't want to mess with the AOB setting on the TC. However, it still would be easier to set the AOB to 12 degrees and the speed to 9.5 (middle of the road for medium speed targets) and shoot from the TC. When the range is close enough, you can't hardly miss, provided they don't have escorts.

New people trying to shoot from an American sub need to be aware that as you rotate the target bearing (periscope) and send in or set a new bearing on the TC, it does not update the AOB. This causes many a missed shot. This is why shooting from the hip became popular here. If you didn't take the time to set up the PK to simulate the target position, you were constantly fighting that TC.

The German U-Boat TC is way better and simpler. When you turn the periscope, the bearing setting changes too as you turn the periscope. And, the AOB setting is geared with it to change at the same rate. So as your target is changing on your bearing, the TC is adjusted automatically to the correct AOB as you go. When the speed is set correctly, you can't miss (well you can, see one of my previous posts). Which means, the only time you have to change the AOB is if the target changes it's physical course, or you change yours. Speed is the same if you're moving or not.

Except he thinks that ALL AOBs are 10 if the bearing is 80 as far as I can tell, when in fact all are possible (half if you add "closing" as a given).

Everyone questioning him has asked the same question, how do you know the AOB is 10, when you have no idea what the intercept angle is. He seems to assume as given that his sub will cross the target at 90 degrees—if that was true, all USN torps would have failed every hit, since they'd all intercept the target at 90 degrees, lol.

Yeah, I understand you're going after a very specific statement of his.

It was my understanding that because the torpedoes had a firing pin problem hitting at 90 degrees like you said. I also understand that the best depth for most damage is right under the keel. This way, the power of the punch has to go through the ship. And as such, don't most hulls have an angle down to the keel. And that most ships had stronger sides than bottoms (even though that would seem to be backwards for best design)? So if the ships have angled hulls to the keel, then shooting at keel + 2 feet should yield nice results. Or does even SH4 model such things?

I usually do the magnetic setting unless forced to (bad weather, excessively long shots, very early war, bad luck).

Bothersome,
8010 as presented here is a "method" of calculating target's speed. It is not a firing method. If I rely on a logical estimate of speed based on the fact that the sonar man reports a "medium speed" and that the target is a merchant which in games term usually means somewhere between 9 and 12 Kts, than what's the use? I can live with a rule of thumb that states for most merchants reported at medium speed a rough speed is 10.5 kts. Please go through the original post to understand how the "method" was initially presented. Many people recognize that there is a potential in the use of "collision courses" but not as implemented here.

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A rule of thumb is an entirely different issue. Saying "we'll assume her AOB 10 be 10, then calculate what the speed would be for that AOB" is one thing---assuming that you'd get a better estimate than just the average of the "medium" speed range.

He keeps presenting the AOB as certainly 10, since he knows (how?) that the collision is at 90 degrees, and knows the bearing.

He's not saying it's a ballpark figure, he's saying the AOB is actually 10.

Start digging your grave buddy. ;) I was allready on it. I was testing the past few days, almost finished. Some how I can't get the later hydrophone improvements to get enabled. And some weirdness with the detection range is going on. You detect when it reaches 34km, but after that it can extend away for 40km before loosing it. Weird. But unpredictability in this mission is something you can count on!

[EDIT] I mean, it's still the same type of contact, on a constant course for most of the time, but you won't get the same course and speed at each attempt.

Here it is. It's JSGME ready. Just like yours it's a Subschool mission (SS10, US only). You'll have to do with the WCA hydro, but stock SH4 still gives you plenty of detection range.

The probability of a certain target course isn't evenly spread out. There is a higher probability to get a target course around 45 or 135 degrees, because of how the random waypoints work. (more points lie in front an behind the center of a waypoint area, compared to courses tangent to the edge of the waypoint area) But that certainly isn't a reason to expect it to be just 45 or 135. It can be made with more even probability, but the waypoint patern is allready complex enough.

http://ricojansen.nl/downloads/RNDap..._Subschool.rar

Mission description:

There's your answer, tater. He has no idea what an angle on the bow is! All this time he's been talking standard US Navy terms and inserting his own meaningless private meaning into it. He sees the 80 degree bearing, he assumes the 90 degree intersect and calculates the AoB from that.

But he has not calculated AoB at all, just the other angle in the triangle that describes the two positions plus the assumed right angle intersection of courses. His entire house of cards is built upon ignorance of his basic terms. Conclusions built upon false premises are fallacious. 8010 falls.

The other fallacy here is the sonar man's calling out the speed. In reality no such thing was possible. Neither was the declaration that the target was closing or going away. The only way to obtain that information was active sonar.

In World War II there were no speed curves, there was no doppler data (which relies on having a recording of the target without doppler shift). We proceed here as if this were a nuclear submarine with a passive sonar capability that can often tell you the name of the target, pull up a complete speed/rpm curve and do a sophisticated motion analysis of the data. That was science fiction then. I don't even think they had conceived of the idea for it to be fiction. They would have laughed at the notion of identification of individual ships by sound signature.

The entire 8010 system is built around gaming the system. In my book that's an invalid procedure. It's nothing short of cheating. And even at all that it tells you little except that you have established a collision course with the target, a useful but not sufficient piece of data for sinking your opponent. It is no technique for putting a torpedo into the side of a target. It is only a way to get close enough to do so IF and only if it is in a narrow 20º cone of the 360º possible for acquired contacts. It rejects 94.44% of contacts (assuming random courses of sub and target) as unworthy of action. That alone is dereliction of duty and would result in a real sub commander losing his command. Just think, 340º of a possible 360º rejected as not engagable! That's worthy of court martial and 20 years hard labor busting rocks.

Ruhe mentions the sonarman giving them the turns on the contact and having that match the speed they had worked up (or guessed). In both cases I think the contact was a sub, though.

I am almost certain that in the '40s they had already "envisioned" everything that was incorporated in the later decades in varius devices and procedures regarding Combat Information. The scientific concepts were known, their use and uselfuness in a combat situation aknowledged. The element that was missinig was "computing power". After the "diode" was invented, after WW2, high speed computing devices start to pop up and ... well you know what happened from thereon.


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