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MajorBooBoo

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Posts posted by MajorBooBoo

  1. I have already posted how they work. repeated here for your reading pleasure.

    "Sound ranging used a straight line base of six very accurately surveyed microphones connected by line to a pen recorder in a CP. This recorded the relative times of arrival at each microphone of the sound of guns firing, which enabled a line to be plotted from each microphone to give a ‘cats-cradle’, resolving this gave the HB location. The record could also show the type of gun. Forward deployed advanced posts ordered the CP to switch on the pen recorder when they heard guns firing. The British equipment was capable of locating guns to range of about 6 miles and an accuracy of about 100 yards. However, these were not sensitive enough for mortars, but improved significantly in 1944 with the arrival of the ‘four pen’ recorder that connected to a line of four microphones (typically 400 to 1000 yards apart) although 8.1-cm mortars remained a problem. Sound ranging could also range CB fire onto a HB using a ‘comparator’, a mechanical device for solving first order differential equations."

    This from

    http://members.tripod.com/~nigelef/index.htm

    Are you more interested in the physics/electronics side then? Theres many issues with ambients/drift/non-repeatability/tuning, etc. I could expand on that. I am responding to what I percieve to be genuine interest and not hostility dripping in your post Brian. I think the voice of calm and reason has come into this thread and his name is Brian. Knowing how things "work" is fine, knowing how they cant work requires somemore than reading.

  2. i bet that I am one of the few people here that has worked on tube based (shudder) electronics. I have also worked with very old data recording technology. I have worked in vibrationally challenging environments. I am very familiar with spectrum analysis.

    Does that make me a WWII era electronics genius and expert on counter battery radar? No. I never said as much. But any post where someone has some information attracts the detractors. It was a very interesting discussion till the last page or so. This is a trend that appears on this board alot.

    I am still hoping that JasonC decides to come back to this therad. Say what you like about him, he is knowledgable and can express himself in a correct technical manner.

    JonS posted:

    "In that paper it is made clear that the RA developed the ability to pick out the distinctive frequencies for different calibres. In effect this meant that they were unhindered by the ambient sound-scape. This was in 1917-18."

    I think he (Jon) was the one from the IS2 thread that jumped on the momentum problem and got it right so I will give him some respect. But I believe that he is assuming something in his last sentence. If it is an fact true and not an assumption, perhaps he can say so.

    Someone else said that the transducers can be directional. This would mean that they would have to be pointed within an angle at the unknown battery.

    Andreas, the thread existed with me in it before you came in with your grandads stories. You could lighten up.

    Finally Bastables, whats your input again? I know that anything that I say to you will not generate a civil attitude since every post I have ever read with you in it sounds like some teenager from Nebraska with a testosterone imbalance. Bet you are a fun drinking partner.

  3. Originally posted by Andreas:

    MBB

    Question - have you ever seen a map of how these posts were placed, or do you indeed know any more than what you are saying here, which is just surmising for all I can tell?

    Well, it is a good thing to see you know all anyway, and I am sure that there is no need to debate this any further, since you pronounced on it. I salute your infinte wisdom, and bow to your knowledge. You are obviously very smart.

    img10.gif

    I believe there are sub-grog catagories.

    Here they are;

    1. Educated Grogs holding degrees. Will even discuss the science behind it all.

    2. Testy Grogs, almost cranky, grogs holding grudges. Humorless and best avoided.

    3. Groggy Grogs. Insominiacs mostly. They make alot of tpying errors.

    4. Grovelling Grogs who, for some unfathomable reason, like to be teachers pets and tattletales mostly.

    None of the above have anything that can be described as a real life, let alone much sex. Modders cant be put into catagories because the people that have studied them lose their minds and quit.

    If anyone has worked with some of the old data recorders, they would know that vibration would have a serious effect on the needle movement not the transducer(microphone).

    heres a mind experiment:

    If multiple batteries, lets say 3 times 105mm german howitzers (4 guns each) that are all located in different areas and thus, different ranges from the sound equipment, all open fire at the same time, what would the recordings be? Are they useful?

    discuss amongst yourselves.

    [ February 10, 2002, 03:58 PM: Message edited by: MajorBooBoo ]

  4. Originally posted by flamingknives:

    I can't quite see something the size of a tank engine getting pushed out through 8-10 mm plate - more likely the welds fail and the plates fall apart.

    I even think the scenario I proposed as a back peddle is also preposterous. Like someone telling me something they read in a Sgt Rock comic book.

    I can explain the turret stuff he posted earlier because it has to do with rotational dynamics/internal explosions and not a strait linear brute force tale like the engine thing.

  5. Originally posted by Andreas:

    </font><blockquote>quote:</font><hr />Originally posted by MajorBooBoo:

    These techniques probably were only good during periods of calm. During a raging battle, the floor of noise from so many weapons firing would be like a jamming device.

    Err, not necessarily. At least not with the German army observation detachments (Beobachtungsabteilungen). If you check out where the LPs/OPs were actually placed, you'll see that they were out of the line, in a rear area. Small-arms fire and tank engine noise would not really be that much of an issue.</font>
  6. "Sound ranging used a straight line base of six very accurately surveyed microphones connected by line to a pen recorder in a CP. This recorded the relative times of arrival at each microphone of the sound of guns firing, which enabled a line to be plotted from each microphone to give a ‘cats-cradle’, resolving this gave the HB location. The record could also show the type of gun. Forward deployed advanced posts ordered the CP to switch on the pen recorder when they heard guns firing. The British equipment was capable of locating guns to range of about 6 miles and an accuracy of about 100 yards. However, these were not sensitive enough for mortars, but improved significantly in 1944 with the arrival of the ‘four pen’ recorder that connected to a line of four microphones (typically 400 to 1000 yards apart) although 8.1-cm mortars remained a problem. Sound ranging could also range CB fire onto a HB using a ‘comparator’, a mechanical device for solving first order differential equations."

    This from

    http://members.tripod.com/~nigelef/index.htm

    These techniques probably were only good during periods of calm. During a raging battle, the floor of noise from so many weapons firing would be like a jamming device.

  7. The shell has a scalar KE (kinetic Energy) of 1/2mv^2 coming in and 1/2mv^2 going back where it came from. Its energy is conserved (theoretically), since you are hypothesising no velocity loss. Wheres this extra energy coming from thats moving tanks and such?

    Jason did a pretty good job of explaining himself, better than his first post here. He is hedging on the real issues about how the shell could possibly wedge in the engine (it might, if moving SLOWLY) and how its going to also then keep moving and pick up another mass (back armor) and all three are going out the back. No way! The engine/shell combo cant rebound back into the tank, they all gotta get out! If I was backed into a corner like he is, I would postulate that the engine/shell combo didnt go out the back but rather rode up the slope of the rear armor (the panther has that rakish look in the back) crashing through the thinner upper deck and landed on the ground.

    JonS is correct because there isnt the case of conservation of momentum when one of the two elastic objects doesnt move. Its a trick question in physics. Ive seen it on tests and thought I would try my luck with it here. He should have just said so but insists on moving the tank!

    For every complex problem there is a solution that is simple, neat, and wrong.

    H. L. Mencken

  8. Originally posted by JonS:

    ...Um, no. In your example momentum is not conserved, it is reversed.

    After the colision the vehicle must move away from the now reflected round with twice the initial momentum of the round in order for total momentum to be conserved.

    If we take the initial momentum of the shell as being 1, we get

    1 + 0 = -1 + x

    I leave to you to work out the value for x ...

    Everyone agree with this?
  9. I'll bump this with a little more info:

    The 122mm AP shell would have to:

    1. Defeat the front hull armor

    2. Move through all bulkheads/etc

    3. Strike the engine block

    4. Become a non-elastic collision at this point and start transferring all energy/momentum to said engine block

    5. Break engine block off its mounts and disengage all exhaust fittings/DRIVESHAFT (!)hoses/lines connecting it to the tank

    6. Move this mass towards the rear armor

    7. This moving mass needs to strike the welded on rear armor and knock it off with its mass*velocity

    The most ridiculous thing is the engine being accelerated in such as short distance to knock off the rear armor plate (basically one piece, I believe, that is 30-40mm thick?????) and jumping through!!!!

    Almost as preposterous is the AP round "burying" itself in the engine block. Anyone that has worked on engines know that there is alot of hollow inside an engine. It is not made of armor and mostly cast iron/aluminum heads. I have fired rifles through engine blocks for christs sake!

    Theres many stories of tanks being perforated all the way front to rear and this is the most unbelievable thing I have read. The superpershing firing on a jagdpanzer comes to mind in addition to the point blank panther vs shermans story I posted before.

  10. Originally posted by JasonC:

    Major BB found it difficult to believe that a 122mm AP knocked the engine out the back of a Panther. If the armor is defeated, then the result is perfectly understandable. Large AP rounds have enourmous ENERGIES, and all of their ENERGY and MOMENTUM has to go somewhere.

    When the armor defeats the round, most of IT is transfered to the tank in its entirety, or carried off by the round itself in ricochet. Notice, however, that a *direct* ricochet (straight back, as if that could happen) would impart *double* the shell momentum to the tank as a whole. Because the armor must accelerate the round off on its new vector, with a net new momentum vector of zero for tank and round taken together.

    (To use a Jasonistic mannerism..um,no)

    Most of IT? IT being what Jason? Energy or Momentum.

    Momentum is conserved in this world.

    The Principle of Conservation of Linear Momentum

    During any interaction in which no external forces act, the total linear momentum is conserved.

    Mass times Velocity. You described a perfectly elastic collision. That is, a ricochet that resulted in the round bouncing directly back from where it came. You never mentioned the tank moving in response , so its change in momentum is????

    Before the collision:

    (Mass of shell) times (velocity)= Value1

    (Mass of Tank) times (Velocity, which is zero)= zero

    After collision:

    (Mass of Shell) times its (Velocity)= -Value1

    (Mass of Tank) times its (Velocity)= zero

    So we see that momentum is conserved in this case (as it should be).

    Expressed in terms of masses and velocities this is equivalent to:

    m1v'1 + m1v1 = m2v'2 + m2v2

    where the primed (') symbols refer to the quantities after collision, and the unprimed symbols refer to the quantities before collision. Obviously one side of the equation is zero.

    Momentum or Energy? Figure it out Jason. How did double the momentum enter into your post? Then I will respond to the rest of your post which also has holes in it. No pun intended.

    http://www.usafa.af.mil/dfp/cockpit-phys/kw2th1a.htm

    Heres a website that has an error(s) in it (I believe), anyone agree?

    [ February 09, 2002, 05:49 PM: Message edited by: MajorBooBoo ]

  11. The other advantage to higher velocity is cover penetration.

    If someone is firing a smg at you and you can get some cover, even a small tree to lay down behind, you have an advantage. The combo of the tree and your helmet giving a degree of protection.

    I have fired AK ammo at different objects and materials. Not sure how it exactly compares to kurz ammo but its impressive. Alot better than most pistol ammo I have fired. At 25 meters it went through two pieces of carbon steel about 1/8" thick. It really punched sideways through the second but did go through. It was copper jacketed ammo.

    Nowadays, form a military standpoint, SMGs are history. Body armor and Kevlar helmets making them nearly useless to carry.

  12. The hard part about destroying a company strongpoint, or any infantry position, is that it usually is in a line. By that, its roughly parrallel to the guns layout. The problem with these rockets is the variation in range they exhibit.

    A strongpoint means dug-in/entrenched/bunkered troops. You need almost direct hits to be effective. So it may be possible to saturate an area with rocket fire (which is outside the CM scope just as is carpet bombing), but it is incredibly wasteful. A really good infantry strongpoint includes Mantraps. This is a reinforced bunker that has no firing slits towards the front. It is usually connected to the infantry fighting positions by shallow trenches that allow the infantry to crawl to them during heavy bombardments. They are usually proof from most indirect fire except direct hits from heavy arty (122 and above perhaps). Hence the name Mantraps. The germans went in for reverse slope defense when they could. The angle on the reverse slope preventing observation of and targeting of fieldworks. the angle helps defeat arty shells because they cant seek out ground as well. mortars are as good as ever.

    Rockets are also pretty useless for helping assaults. Proper assaults come in under protective fires from arty and mortars. The key being to let up only when your troops close (and sometimes take a few blue-onblue casualties). Most nations discovered this sooner (midwar-1918 WWI) or later (Sometime in WWII, sometimes relearned).

    Rockets, to me, are akin to airstrikes and should share the heavy payload effect of airstrikes. Big bangs, big craters, big terror.

  13. I find that hard to believe. The engine was driven out the back? The back armor being welded to the tank at the time? An armor piercing shell would just punch through an engine block, not get the whole thing moving.

    More than likely (if it happened at all.. SCALE MODELOR?), woould be that an internal catastrophic explosion from the panthers own stored ammunition could detonate sympathetically and rip the tank apart.

    I have read accounts of Panther AP (at point blank range) completely penetrating a Sherman's front/engine/rear and then bouncing off the front armor of the Sherman behind it. It didnt take any souveniers along for the ride!

    [ February 09, 2002, 11:50 AM: Message edited by: MajorBooBoo ]

  14. Originally posted by Vanir Ausf B:

    Before you guys get too much further into this, you may want to read the following thread:

    MP-44 vs SMG discrepancies

    .

    "Almost any bullet is going fast enough to wound or kill. In fact, sometimes high-speed bullets (like from rifles) can go fast enough that they pass right through a person and do (a little) less damage than slower bullets."

    This is from that other thread. I would agree with the first part but completetly disagree with the second. HV bullets create a shockwave that is devastating to any but the smallest body part hit (the forearms and lower leg/no bone strikes). The shape/size of the shockwave is like a small football area inside the victem. The displacement of internal organs and compression of spinal bone/nerve will drop a human (and large animals).

    I also believe that police use SMG and pistol ammo(and shotguns), in addition to the other reason stated above, because they dont want bullets careening everywhere in a populated area. police should shoot to kill and preferably have the bullet lodge in the target perp.

  15. Originally posted by apex:

    </font><blockquote>quote:</font><hr />The major discovery being that HE isnt important but fragmentation is (if you want to shoot down a plane). They optimized the autocannons for planes and perhaps 88 shells this way

    Wrong. German 20mm cannons used a variety of ammunition, among them were the "Minengeschoss", mine shell, very thin-walled shells with little fragmentation effect but excellent pressure effect that caused major damage to aircraft structure on hits. Used from the Battle of Britain to the end of the war.

    apex</font>

  16. Cocking ones ear for mortars is really part of non-combat missions (otherwise the sound would get lost in all the battle noise of a combat mission). A vet can get so good that he can discern if the *cough* of a mortar is directed towards him or not. I observed 81mm firing and at close range theres almost a ringing to it. Depends on the charge they use too.

  17. Originally posted by MajorBooBoo:

    These discussions about tests make me wonder if the following would be a way of "booting" up WWII firepower. By booting up, I mean bringing it up through the ages.

    Could testing be done first with just rifle armed troops? This would allow a base that other layers of forepower can be built on? Once the rifle models out well (meets a certain design specification for effectiveness, etc), layer on different small arms and then finally MGs of different types? Sort of a Law of Partial Pressures approach. It is difficult to say if MGs are modeled well if there is the prescence of other weapon types in the same test.

    These tests, of course, require many runs to be of any use and would take alot of time.

    I am reposting this again. I also agree that Jason C does have some validity and reject the notion that CM is not a sum of its parts. That isnt in the spirit of the discussion and is an insult to intelligence.

    MGs should be realistic when used alone or in concert with other weapons. Many times, MGs in the game get cut offand are isolated. Would I need to get troops over there to get proper modeling?

  18. Originally posted by Big Time Software:

    Maple,

    Good info there! Looks like one of the fear factors was that the troops could hear them launch, but until they landed they would have no idea where they were destined for. That is quite different from both artillery and mortars.

    Steve

    I dont think thats quite right. It IS the case for mortars, you CAN hear them fire (if they arent behind a hill or very far away or the wind is wrong) but you DONT hear them approach. That's what is said to make them so hated.

    I think the rocket example given where the sound wasnt heard was the phenomena of a shell/rocket coming right at you. The sound being behind it. If arty or especially rockets fire over you or to your sides, you get the distinctive screeming/whistling/etc. This again is not the case for mortars.

    So if a spotting round is lucky enough to get you dead nuts, it doesnt matter what fired it. In this case, the near hit was in front of the troops and the blast was possibly blocked by the rocket case!

    I have read other accounts of the casings being splayed open. It further demonstrates that the rocket weight was not shrapnel producing metal.

  19. Originally posted by karch:

    </font><blockquote>quote:</font><hr />Originally posted by Puff the Magic Dragon:

    BTW, Steve - I wonder why a blind fired barrage (doesn't matter which artillery) comes down with greater disperse. This seems to be completly unrealistic. To cause this effect, each barrel needs a slightly different target zone, but what I have seen in the army, a target order is always given for the whole battery*. So, the 'blind barrage' would come in with the same disperse as a 'LOS barrage'. Instead a bigger disperse, it goes to the wrong place. Indictee, what can you say for your defense? ;)

    *(exept they prepare a 'target marker', of course)

    Because you would ASK for greater dispersion. If you can't see where you are firing and you want a better chance of hitting something "somewhere over there". Getting higher dispersion would give you a better chance of hitting SOMETHING rather than a nice tight pattern hitting squat. I figured this was accurate and correct. But not being a 33 year old WWII artillery vet, I really don't know. It just seems right to me. I'd probably ask for higher dispersion if I couldn't see where anything was landing.[/QB]</font>
  20. I will try to find some data on the speed of superquick fuzes in WWII. A point to remember is that a mortar is moving much slowly than a Gun or Howitzer round and therefore any propagation delay associated with striking/detonating is less. Also, the nose is the fuze and if buried, then it doesnt really matter as much as a angled shell burying itself. I have seen the effects of 81mm mortar rounds on the ground and it is typically a web shape and a very small pocket. It was on dry earth though.

    Interesting stuff all around. I agree that pre-game bombardments might be a good place for nebelwerfers. Firing, limbering, moving to a new place, unlimbering, reloading and firing again is outside the scope of the game.

    By the way, if the goal of a nebelwerfer was to destroy a house, it wouldnt want to be any feet away! blast force falls off with distance.

    Mortars attached at Bn or Rg level are just so much closer than Corp level rockets in the CM scope of things.

  21. Originally posted by Simon Fox:

    Interestingly this point seems to have paralells in British operational research of the time. As has been alluded to in this thread a number of factors contribute to the effectiveness of a particular shell/rocket/round type in addition to merely the weight of explosive including explosive type, fusing, metallurgy of the casing, etc, etc.
  22. Originally posted by redwolf:

    That is correct. However, while the Nebelwerfers had the disadvantage of needing more supply resources for a given effect of a barrage, they have a real advantage over real guns. That is that the firing system is much easier to move and/or to keep alife and available in an environment of total enemy air superiority and/or frequent hasty retreats. Also, at least the Americans had means to locate enemy batteries for counterfire. While primitive and inexact, they had all the ammo they wanted to saturate an area around the suspected location. Overall, I think the Germans were better off with the Nebelwerfers at the West Front, especially since they met inexperienced or otherwise careless troops frequently, at least in Normandy.

    Everyone had a means to detect them. They gave off plumes of smoke and fire.

    I read that Nebeltruppen sometimes took casualties similar to frontline troops. They really broadcast what they were doing and any plane in the area could vector in on the plumes and search the immediate area especially the roads.

    Tube artillery would be better off to stay put or to lay back and use longer ranges to stay alive. Nebeltruppen couldnt do that.

    I am not sure why you think they had all the ammo the wanted to saturate an area. I cant follow that.

    spotting rounds for this form of arty are thumb sketchy at best. Since the rockets have such a variation in range and perpendicular, who's to say a ranging rocket is a good indicator? If it is near target and actually a specimin of being on the outside of its envelope, will the rest of the barrage to centered off target? I would guess accuracy would depend on range and would further guess that long range could have been firing at zip codes..

  23. Originally posted by Spook:

    </font><blockquote>quote:</font><hr />Originally posted by MajorBooBoo:

    Nebelwerfers should be very expensive and rare in the game. Like airpower.

    NW's should certainly be tempered by a rarity system, of course. But concerning certain periods and campaigns, rarity is still a relative value. By example of Normandy, NW's made up a significant portion of German corps-level artillery; at least seven battalions' worth, IIRC.</font>
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