MajorBooBoo

I can verify this! If you have two mikes (x1,y1) and (x2,y2) and a time=distance difference dr12 then you have three equations r1^2 = (x-x1)^2 + (y-y1)^2 r2^2 = (x-x2)^2 + (y-y2)^2 r2 = r1 + dr12 for the FOUR unknowns x,y,r1,r2 Regards, Thomm</font>

Since redwolf is probably working and wont be home for hours, I would like to dare anyone to solve the extra credit problem posted. He has already expressed a desire not to do it so I thought I would throw it up for grabs. Just post what you think the answer is, not how you got it. winner gets to play me in CMBO. take speed of sound to be 343 M/sec for the sake of the problem.

Are you saying that CB is beyond CMs scope? I think that it could be part of the game. Not something that is directly controlled by the player (or maybe it could be part of setup) but something that would effect the players use of arty. heres some cases: Player in CMxx decides to order a barrage of one shell each on a TRP. In this case, he is minimizing the "sound exposure" because there is no need for ranging shots and the guns only fire once each. Player in CMxx calls for a non-stop shelacking by his off-board arty. He isnt firing on a TRP. he is using an inexperienced FO too. Perhaps the arty gets interrupted mid-barrage and is unavailable for a few turns also.

I apologize. Could you post just the math then? Or expand on this below..I would probably take a different mathematical approach but am curious as to how you are finding these "relative" lengths. It may or may not be the trivial problem you think it is (or if I am wrong, I apologize again). I hope the math of a triangle with one known side length and the relative lengths of the other two is trivial enough that it doesn't have to be demonstrated. No I'm not dogding, but I would have to be home to make a drawing. [ February 12, 2002, 07:49 PM: Message edited by: MajorBooBoo ]

redwolf Given the following.... How can the speed of sound be used to determine where a gun is that made that sound? An ideal example will be used to demonstrate. Two sound/time observers are positioned at two seperate points on a map. They know exactly where they are from ideal survey. They have perfectly synchronized time equipment. A gun that they cannot observe at all, fires in the distance. The sound travels from the source outward till it "strikes" one of our ideal observers. He then records to the microsecond when the event occurred to him. The sound then travels outward still till it attains a radius that reaches the other observer. He then records the exact micosecond it struck him. The differential time can then be obtained by comparing the recorded time events. The mathematics behind this is to solve for the two "circles". Simplistically, there are points that could have made circles that fit the time differential. How many solutions are there? In this ideal case, there are two solutions. Since the sound reached one observer before the other, then the two solutions are to the side of the first sound recorded. One solution is a mirror of the other. That is, it can be flipped ove, if you will, and put on the map so that it would overlap the other solution. Since one solution is in friendly territory, it is not the guns location. Explain the math behind the time differential. how is it used and what are the equations. Extra credit: Solve this.. The two mikes are 1000 meters apart. The sound reached the one on the left first. The sound was reached at the second one 1.18 seconds later. The resolution is +/- 0.01 second. Whats the area (error) the battery can be in? (Take the battery to be a point source) assume perfect knowledge of mikes location. neglect all other error sources. Good luck.. this post will self destruct in 10 seconds.... [ February 12, 2002, 04:55 PM: Message edited by: MajorBooBoo ]

That would be fine then. There seems to be an influx of other people now, thanks. Good day.

1) Do not show the impact of unobserved rounds to the player. That is a strong gameplay twist, basically that would only be worthwhile if you had terrain fow-of-way as well. I like this also. Perhaps a "noise" marker could eminate from the general area. Like seismic circles pulsing or something like that. not giving away the exact locations but just the direction. In regards to ambients/background noise, I am also fully prepared to answer any questions regarding this.

The thread started out as an inquiry into the effectiveness of the 15cm variety of nebelwerfer. The payload being small and the fragmentation effect also small. Weapons were compared/preffered to it. The thread took a couple turns and the current discussion seemed to get sidetracked on if I could describe how sound ranging functions. I provided, what I believe, to be a very good outline of the physical principles behind the technology in a question and answer form. I could also take a stab at the actual electronics/recorders/etc. Other people probably have good info on how the technology was employed in the field as far as layout of the orgs, special tactics, counter tactics, etc. I could also do the math part but why dont you take a shot at it?

Nebelwerfers, it seems, were not THAT susceptible to CB. They did not have a distinctive "explosive" report or ringing frequency (from a hard barrel that just shot out a heavy shell) on firing. The main CB method, I would presume, would be to see the trails of smoke they producd on firing (or motor flames as they streaked skyward at night). This could be observed from different angles and the range worked out. In fog or at night behind hilly terrain they could be a menace. The website I reffed mentions CB against them to be a jobbed out task handled by the counter-arty or counter-mortar depending on the situation. In my experience, that means neither one could really do it right! [ February 12, 2002, 12:08 PM: Message edited by: MajorBooBoo ]

Wurgranate 42 rocket - The German 21cm ( 8.27in ) Wurfgranate 42 was a spin-stabilized HE rocket which resembled an artillery shell in shape. The forward part held a filling of 10.16kg ( 22.41bs ) of Amatol, while in the rear section carried the rocket motor, seven thick sticks of smokeless powder with an electrical igniter. This was exhauted through 22 canted vents in the base to spin and propel the rocket. The nose was covered by a ballistic cap which concealed an impact fuse. The launcher was the 21cm Nebelwerfer 42, a cluster of five barrels mounted on the same two-wheeled, split trail carriage as the 15cm Nebelwerfer. The rockets were fired by depressing a plunger from a safe distance away. Is the 21cm a nose throwing HE weapon or a ass-dragging HE bomb? Anyone know the layouts of the larger weapons? Do you have a source for your info Brian?

err, so? You say I am contributing then. Thank you. I am NOT going to try and respond to the other parts of your post. Theres nothing in it really. You want me to respond in kind, bring some kind of brew-ha about and just spiral down. You will then alert BTS's to what you have "discovered". I dont want to be part of the demonstrative world of Mr Dorosh. I respectfully decline. To everyone: I think this thread started out OK (although Steve and Jason werent the most civil either) and lots of good info was being discussed/presented. People who later came in brought the 'tude of the "So you think you know everything, HUH?" mindset. Sorry, four years of high school was enough for me, I dont need any more of that. I made an observation that people use some very curt/abrupt introductions. They arent very polite. Thats all. I tried to interject some self-effecing humor and maybe it fell flat. A thousand pardons. I told Andreas to lighten up. And he did. Good for him. Hes a better person than some others here.

Bagration "When this buildup was completed in the Soviet offensive zone the Russians had amassed over 1.2 million troops, against Army Group Center's total strength of 700,000. The total Soviet strength ready to participate in the attack, including reserve forces held back from the front, was nearly 2.5 million. 4,000 tanks, 24,400 cannon, and 5,300 aircraft gave the Soviets upward of 10:1 odds at the designated assault points. Even when German intelligence began to detect the scope of the buildup, OKH remained convinced that the main effort would remain in the south. This was wishful thinking on the part of the Germans for this was the one place where they could amass considerable combat power to meet any threat." http://www.warfarehq.com/After%20Action%20Reports/TOAW%20AAR/bagration_berlin_aar.htm I would say that the swing wasn't AGAINST the guy with better tanks but WITH the guy with MORE tanks. Tigers and Panthers were not the majority tanks considering the Tiger/Panther/MkIV/StuGs/Etc fleet. Up till Early 1944, pzIII still were part of that fleet also. The germans had maybe a few hundred panther and a similar (maybe less) amount of tiger I on the WHOLE eastern front (total) at the end of May 44. About 2/3 operational to boot. PIv strength was about double the panther strength. They got swamped and stomped.

I think this thread, despite its shortcomings, is interesting. Interesting, because its just typical of the exchanges around here. Maybe Steve can comment on that. I believe the same elements always come into technical threads and stirs up the crap. Heres a very good read and I wonder if people can see themselves. http://www.vandruff.com/art_converse.html#a I dont mind a little verbal fisticuffs if someone is putting out (contributing material/info/experience to a thread), but Bastables is an example of a pure Detractor. even with Steves post, he continues to just try to prod me and others against me. All because he fancies himself ironic evidently. Anyway, Someone tried to put me on the spot and I came through. My explanation of the principles behind CB was from just reflecting on the science behind the situation. Brian, who tried to intimidate me (please), is now quiet. I will acknowledge that Andreas does seem to be knowledgable and was man enough to recognize what I posted was a good effort. I wasnt sure if JonS meant any sarcasm about my cut-n-share post. Its from that reffed website of course.

Since Brian cant form an intelligent clear question we will have to move on.</font>

[ February 12, 2002, 12:29 AM: Message edited by: MajorBooBoo ]

http://rt66.com/~korteng/SmallArms/mghvrus2.htm Good source of general info since alot of it is WWII

err, thanks

Counter-Bombardment Locating HBs and mortars was not enough, as WW1 had shown a CB organisation was required. From early in the war each Corps HQRA had a CB staff some 30 strong including seven officers. The doctrine was to handle CB at corps level, devolving to division level in mobile operations. The corps CB staff could provide CB staff to two forward divisions. However, mortars were a major menace (as were nebelwerfers when they appeared) and being short range their deployment was very different to guns. This led to the creation of separate counter-mortar (CM) staffs, usually at brigade HQs, in NW Europe and Italy, often with an infantry officer as the CMO. Nebelwerfers didn’t fit neatly into either CB or CM and one or other would take responsibility by local agreement. As the AGRAs evolved they had an increasingly important role with their own CB staff and in the final stages of the war took responsibility for the CB targets in major formation fire plans. CB policy could be either active or passive. Active meant attacking HB when they were located. Passive meant not attacking them until an appropriate time. In practice it was seldom this simple. HB could be destroyed or neutralised. It was recognised that destruction was best achieved by using destruction procedures with a single gun engaging a single gun, towed guns being notoriously difficult to destroy. Neutralisation was in fact a misnomer; the method of attack was short bursts of fire at irregular intervals, typically using a ratio of initially two but later 5 - 10 guns against one. The objective was to cause casualties and damage to achieve a degree of neutralisation. Predicted fire was seldom really effective for CB, even when 'sweep and search' procedures were used to increase the size of the area shelled. As in WW1, air observation was the best solution and AOPs were extensively used for observed CB fire although they often relied on seeing guns firing, and it needed luck to get the aircraft into position when HB fired only a few rounds at a time. Sound ranging could also range guns onto located batteries using the comparator. CB fire used a special type of on-call fire plan - the 'Bombard'. The CB staff prepared HB Lists and issued them to batteries, which produced data to engage them, excluding corrections for non-standard conditions, which were produced when the HB was engaged. The ‘bombard’ procedure, could be on-call or scheduled during a fire plan or invoked any time against a troublesome HB, used the HB List. However, in July 1944 neutralisation was generally abandoned for CB fire, not least because the British had defeated the German artillery. Air observed one-on-one-destruction shoots became normal. The bombard procedure was for the CB staff to order a mix of batteries or troops to engage a listed HB using predicted fire. Aim points were distributed depending on the information available about the HB, including aiming ‘gun-on-gun’ if their co-ordinates were known. Short bursts of fire at irregular intervals were applied. In Italy, German guns were often concealed in caves and bunkers so neutralisation was ineffective. This led to the use of AOP observed destruction shoots. The problem was that these took a long time, perhaps only one per sortie, this in turn led to the Festa system where an AOP engaged several protected guns simultaneously during each sortie. The most used guns for counter-mortar fire were 7.2-inch howitzers firing air burst. 3.7-inch HAA were also often used. Upper register fire using air-burst was generally preferred for the former. These guns were usually ‘At Priority Call' to the CM officer to ensure a quick response before the mortars moved. The only problem was that the 8.1-cm mortars usually deployed well forward and this could present an own troops safety problem when using heavy and medium guns, particularly with upper register fire. The CB staff were provided with dedicated radio communications and were not just concerned with locating HB and attacking them. They were also an intelligence agency responsible for CB Intelligence. They used various specialist techniques to deduce information about the enemy order of battle and impending activities from the deployment and firing patterns of their guns and mortars. These included the Shelling Plot, Hostile Battery History Sheet, Gun Density Trace, and Shelling Connectivity and Activity Trace. http://members.tripod.com/~nigelef/maindoc.htm#Survey,%20Meteorology%20and%20Calibration

From a pure physics standpoint the following could matter: 1. Elevation of "listening" equipment, all at the same perhaps. Hopefully with some elevation advantage over the guns. 2. As far forward as possible (there could be noise issues from the battlefield) because of range limitations. The enemy could just pull back and defeat you otherwise. 3. Distances between equipment has been posted before 4. Analysis of terrain that could cause echoes and other noise problems. 5. The forward guy (who initiates the turn on of equipment) has to be far enough in front of the electronic transducers so that the reaction time between his being alerted and relaying the turn on is actuated before the sound hits the transducers. These just came to mind but there could be alot of other issues.

I have read of panther turret sides opening up/falling off on occasion. If you have ever stood next to a panther, and seen how large it is and vulnerable to the sides, perhaps it would not be your choice of tank. I can believe that an AP would penetrate through and perhaps knock off the back plate of the hull (But not take the engine along!). the reason being that the welds are to strengthen outside attack. That overlapping german welding interlock does not help an inside attack. Also gravity might help drop that plate like a ramp! But I havent seen a pic like this of a panther. To get back to the main point of this thread, The IS2s (to me) should be used in combo with terrific arty/rocket/sturmovic and assault guns to crash a selected area of the german line. The HE rounds being spent taking out bunkers and other stubborn points of resistance. After the main breakthrough, these tanks could help hold the breakthroughs flanks with the AP they carry to stop german armor counterattacks. I wouldnt use them as offensive weapons against german armor.The rates of fire and inabilty to unload and switch ammo type (they probably cleared the barrel by firing) makes them ponderous.

"Some marks out of 10 for the principles." Sorry, not accepting marks anymore. Me wanty the Eurobucks please.. I probably know more about the technology (the electronics, recorders, etc and the foibles of such) than the color shade of the uniforms worn by All the Worlds CB. I would defer that expertise to others. I can dig up some info about the RA if you like and you could post about the Heer. Sound fair (no pun intended)? [ February 11, 2002, 11:21 AM: Message edited by: MajorBooBoo ]

As promised I will expand on my understanding of this technology. Since only a vague question could be posed, I will instead ask my own questions and answer them. As any intelligent person would, I will start with the principles. Explain the physical principle behind "sound ranging"? The physical principle used is the constant speed of sound under meteorlogical conditions. If these conditions are known (temp, pressure, etc), then the speed of sound is known. How is the speed of sound useful in sound ranging? A sound event, such as a gun firing, eminates like a constantly increasing circle (when viewed from above in a X-Y coordinate system) where the radius is increasing at a constant rate. That rate is the speed of sound. How can that be used to determine where a gun is that made that sound? An ideal example will be used to demonstrate. Two sound/time observers are positioned at two seperate points on a map. They know exactly where they are from ideal survey. They have perfectly synchronized time equipment. A gun that they cannot observe at all, fires in the distance. The sound travels from the source outward till it "strikes" one of our ideal observers. He then records to the microsecond when the event occurred to him. The sound then travels outward still till it attains a radius that reaches the other observer. He then records the exact micosecond it struck him. The differential time can then be obtained by comparing the recorded time events. The mathematics behind this is to solve for the two "circles". Simplistically, there are points that could have made circles that fit the time differential. How many solutions are there? In this ideal case, there are two solutions. Since the sound reached one observer before the other, then the two solutions are to the side of the first sound recorded. One solution is a mirror of the other. That is, it can be flipped ove, if you will, and put on the map so that it would overlap the other solution. Since one solution is in friendly territory, it is not the guns location. What if the sound reaches both observers at the same time ideally? Huh? HUH? What do you have to say about THAT? In this case, the range might not be determined, but the direction is. Both observers could be on the wave front as it passes over them at the same time (meaning they are both equidistant from the source). A line that is then drawn between them, equidistant to both of them along all its length, will intersect the enemy gun somewhere. The further the gun is away (in real life) the more error introduced. Not a desired layout and the observers are placed so as to benefit from a time differential. In this special case, how could the range be determined? The time of the flash of the firing gun would need to be seen and recorded. Since the speed of light is relatively instantaneous, it can be compared with either of the sound arrivals and the range determined. This is another gun location method though.

Since Brian cant form an intelligent clear question we will have to move on. I dont know that much about WWI and leave that to Mr Dorosh and friends. I do believe the british were among the best of the nations in electronics during WWII. Radar in particular stands out. From what I have read, the RA had developed counter mortar sound ranging , late in teh war, and that is why it was brought into this thread. Earlier, Steve had mentioned something about 81mm being not so loud or such. Then look what happened, all the queens subjects come piling in and show their manners. All kidding aside. I will post a short description of the basic principles (sound speed and all) behind this and the generalized system level workings. If more detail or debate ensues, oh so the more fun. Good night.

Its like talking to a brick wall. I repeat. How things can be explained really depends on your education, experience and your technical background. Someone that asks me "how tings woik" is perhaps unaware of different levels of technical/physical principles. You mentioned you read a book (congrats by the way), what other education, experience, intercourse have you had with this subject? Do I have to make a list of questions and you can choose the one that you think is the correct one? I mean cmon, I have to do all the work? (PS How were they mounted? Why they were put on Bren Gun Tripods, of course...)

I hate to break your bubble but the microphones dont record diddly. You are revealing yourself to be technically incorrect in even asking the question you are trying to impress upon everyone that you (and the others you have selected in your royal "we") know so well!!!!! I am not kidding. microphones are transducers that create signals. Sorry pally. I cant explain things that you are likely to misunderstand since you cant ask the question right! I beg your pardon but you are biting off more than you can chew. How things work can be explained at many levels. Where you at? Lets see if you, no cheating now, can ask a clear question that I will answer. Its still early where you are so dont rush.