Amizaur

The crew of the Panther shooting at the wind mill could meaure the approximate range to target simply from a map. They would have range set about right for the first shot, and correct with next shots. They could also use some kind of rangefinder device. Probably there was no rush with the shooting, they could take their time preparing for it, carefully measuring or estimating the range ect.

Any shell trajectory watched along it's path on a high zoom setting will look like a seriously curved one, when in fact it's descending at mere 1.5deg or so. It's just effect of zoom I think. It looks like that in any game, and probably in real life too - watching trough the sight it seems that the shell is dropping at the target from above at a "high angle".

You are absolutely right, but I didn't mean to do a "proper" testing, just to check if my observations were true or false. Even short dedicated test has shown that I was wrong and that unbuttoned spotting is "about the same" for PzIV and T-34, this is all wanted to know .

I have repeated several times the same test with 10 lanes of T-34/76 vs some German tank, and always the T-34 were on average spotting worse than let's say PzIV. To draw definite conclusions I would have to repeat those tests making sure the crews were of equal quality and all else being equal too. P.S. Seems I was wrong. I tested this again using PzIVs, T-34/85 and T-34/76. Seems that unbuttoned spotting is more or les equal for both sides at 1000m. All regulars. (Possibly T-34/76 was a little worse unbuttoned that T-34/85 and PzIV, but it could be just a glitch. Or maybe it's effect of 4 man crew ?) While buttoned, the PzIV had some advantage over T-34/85, the T-34/76 from 1942 Early was outclassed completly - it had problems to detect any Germans at all at 1000m buttoned. Spotting while buttoned was done head-on. Would be interesting to set tanks side by side at 1000m and see if there is any difference (no gunsight used for spotting). When I noticed a difference in testing, Russian side had to be buttoned or the crew quality was different. P.S. Spotting to the side while buttoned is MUCH better for Germans (PzIV) than for Russians (T-34) - at 1000m range. I think it's ok considering better quality of German armored glass in commander's cupola vision slots and poor quality of Russian observation periscopes.

Maybe we get "commander's eye" view and "gunsight" view levels in some future version of the engine ? That would make setting hull-down and full parade much more easy and safe, and also checking the gunner's field of view possible.

I guess the game assumes some gunner ranging error at then start and then it's reduced every next shot, and soon (3rd shot?) it's reduced simply to zero. Such modelling works very well IMO at ranges of about 1000m, but from above test it would seem that it's not enough to modell long range gunnery. To correct that, it could be changed in a way that at longer ranges it would have to take more shots to reduce ranging error to zero, for example 5 shots for 2000m ect. Or - IMO a better and more realistic way to modell it - the ranging error could be exponentially reduced by some % every shot (randomised a bit up or down) but never really reach zero. This way at long ranges even small 5-10% range error remaining after initial 2-3 shots would still count and ranging error would have to be reduced in further few shots to achieve actual direct hits. On the other hand at a range of 1000m such small error (like 5%) would be not important and direct hits (although no precise hits in center of mass) would be possible from 2-3 shot. Sounds realistic. The whole issue needs more testing and a serie of at least 100 shots would be needed to draw any conclusions. Two words of advice for Kauz and other testers: - make several lanes on your testing range (T-34/85 and a target) OR restart the scenario for each single test (I found it most convenient for me to restart the test scenario from a saved game, with everything set up and ready for specyfic test - targets spotted, orders given). DO NOT set one shooter and several targets when testing first-shot accuracy and ranging efficiency. It's because the shooting tank "remembers" the range setting used in the last shooting and it's starts shooting at the next (close by) target with correct range and full accuracy. How to note and interpret the results ? Several methods are possible, each one holding little different information. You could note number of shots to get first hit in each single test - the information that is most interesting for you - but as the spread of shells at 2000m is considerable, tank can miss even with range-error reduced to zero. Better would be to make a table and note hit/miss or the first 5 or 10 shots, and then after collecting 100 results, from this table you can get much more info - average numbers of shots to hit, accuracy of the 1st, 2nd, 3rd, 4th ect shot, and from that we can deduct how the ranging error is reduced - it's after some number of shots when the accuracy reaches it's max and it's constans afterwards. P.S. ---> Kunz - the gunsight of a T-34/85 was in most ways technically not worse in any way from PzIV sight or early Panther sight. It has similar field of view, had similar (but more simply realised) moving scales for aiming, had all the lateral mils scales needed for range estimation. The sight graticule had everything a Tiger sight graticule had, although it was drawn different. Rangefinding using T-34/85 gunsight: If we talk about older Russian sight, they were not a simple cross too - had all needed lateral scales that could be used for range estimation too, if trained for, only placed less conveniently so not as quick to use: T-34/76 sight or early T-34/85 gunsight look: T-26 era gunsight: The difference would be in quality of glass and manufacturing. The picture would be not as clear and not as bright as in German sights - but on a bright day in an open field it wouldn't make much difference (if at all) when targeting tanks in the open. Some say the picture could be not clear at the edges of FOV, only center of FOV being clear. Maybe in early war, 1942-1943 tanks. After all, Russians bought in 1930's a whole Zeiss factory equipment and licences, so they could make optical devices not worse than Germans did 5-10 years before. And beside improvements of anti-reflection layers, I believe there were no breaktroughs in optical designs in those years. Pre-war Russian optics were of good quality, it dropped considerably at the beginning of the war (mass production, relocation of factories) but improved again later, just as quality of everything else. Not German level, but good enough. It's hard to imagine for me HOW POOR would have to be quality of gunsight to seriously affect fire accuracy at ranges of 1000-1500m. The few pieces of old Russian optical devices (binoculars, gunsights) I looked trough were just normal - I could get sharp view and observe things at any range. There were no magical "fog" effect that would prevent me from seeing sharp at 2000m. The only limitation on long ranges was the small magnification of the sight, but it was exactly same for most German sights - 2.5x magnification in PzIV was even less than 4x magnification in T-34/85. I have a Russian war-time mass produced artillery sight and the picture is as good and clear as in any mass produced optical device - like binoculars or telescopes you can buy today. So definitely good enough. I know some German sights had somewhat more clear and sharp view (like in an expensive binocular/telescope), but this is really advantageous only on extreme ranges and in poor light conditions. On a clear day on average tank-duel ranges - no practical difference IMO. I hane not seen any easily noticeable difference. I have no perfect eyesight (slight astigmatism), maybe a person with eagle-eyesight would notice a difference on long ranges, don't know. If someone have such a "poor" Russian war-time gunsight or binoculars have looked trough such "poor" gunsight, please share your experience. As for popular beliefs that better German optics should mean better spotting at ranges in game like 1000-1500m - people, come on, use some common sense ! Spotting was made mainly by commander eyes, either using binoculars (longer ranges) or by using naked eye. Other crewmembers (if free from other duties) could spot too - also with naked eyes. Spotting a target by a gunner using it's gunsight was rather uncommon, as he had very narrow field of view. If the German gunner scanned for targets using gunsight it was because he had no other way to spot (or see). Anyway - commander's binoculars were much better at spotting long range targets that gunner's sight. If naked eye was used - German naked eye is in no way better than Russian naked eye ! So if both tanks had a separate commander performing naked eye spotting, we can assume both were spotting equally good. It's just a personal ability to have good eyesight and ability to spot things. This ability could only further depend on combat experience (so CM creqw quality, equally for both sides). If more (unbuttoned) crewmembers were spotting, the probability of target detection could be higher (or time to detection shorter), especially at short range (more pairs of eyes looking in different directions). If a commander's binoculars were used, again - do we really believe that average German military binoculars were so much better than average Russian military binoculars that it affected target spotting ability at ranges of 1000-2000m ? I would say that in a clear bright day the difference would be very small when detecting tanks at distyances of 500-2000m (detecting a camuflaged AT gun from distance is another thing). From extremally long ranges some German commanders could use scissors-type artillery binocular sigh, with great magnification and stereoscopic view, that's a tool for spotting, but that would be practical only at really long ranges, at average ranges scanning using binoculars would be faster and more efficient. (the most important advantage of scissors-type binoculars was that it allowed commander to remain protected while scanning, in situations when enemy snipers were a threat). So I find it strange, that in my shooting tests unbuttoned T-34s have hard time spotting German tanks at all in an open field from 1000m (!), when Germans (PzIV) are spotting them much more easily. Are Russian binoculars so bad in the game ? In an open field anyone can easily spot a tank from 1000m, no binoculars needed ! (only for identification). Those Russians probably all have medical eyes/sight problems... What WAS worse in Russian optical devices: - much worse quality of "armored glass" for vision slots - it was often dark, coloured and gave no clear view. - Russian observation periscopes like PT-1 were very primitive devices, I heard of them being made from two polished metal plates as a mirrors. The view quality was said to be limited. It was rather to be used at close and medium ranges while staying protected (no magnification, wide FOV, rotating 360deg), for long range spotting the quality of view would be much worse than unbuttoned naked eye. It definitely was not as good as German true periscope devices with glass mirrors.

Yes I tried RO and RO2 years ago . I even made a mod for RO1 tank realism. But RO2 was a poor at simulating tanks. Abandoned it. Steel Fury was excellent, but no multiplayer. Now I enjoy War of Thunder tanks, they feel well when driving, I wish CM tanks behaved this way. The gunnery is not advanced yet, whole tank part is still beta, but it may be interesting multiplayer "almost sim".

Fantastic video you are a tallented director What is the mod for that T-34 sounds with loud tracks effect ? P.S. This video shows at 1.20 and 2.15 that currently in CMRT reaction time of tanks (time between noticing a target and shooting) looks and feels quite unrealistic. Shooting just after the tank has stopped looks and feels quite unrealistic too. There should be some minimum time after the tank has stopped, before it can fire - time for stabilising the whole tank, to stop rocking on it's suspension after braking and then for the gunner to elevate/depress the gun which in every tank was done with hand cranking and wasn't very fast. Also when a tank is reversing, there should be a 1-2s pause before it can move forward again - changing the gears is not instant. Same for changing from forward to reverse. Here the Tiger reverses and in split of second moves forward again. It's not so important for realism from tactical point of view - but it would look much more natural and create a better feel of immersion and "feel of realism" too. In above video in 0.50 tank maneuvers (reverse, forward) so fast that it looks not natural.

Tested. I tested penetration effects and observed the above watching about 200 penetrations. The crewmen that is to be killed is randomly chosed, mainly from occupants of the hit part (hull or turret). I'll try to show some statistics later, but for now - this is what i just observed, without through analysis. P.S. It is random for hull, for sure. I didn't bother to determine if it's the same for turret, I'm assuming it is.

I would add one more thing needed to be modelled, to achieve realistic behaviour of tanks - realistic delays for passing orders and info between crewmembers. And also realistic delays for crewmembers proceeding those orders. It could be abstracted as random delays between target spotting by the TC (or other crewmember) and resulting reaction of the tank (it's movement, usage of weapons).

It's not modelled. When a shell hits the front hull of the T-34, it's random if the driver or the machinegunner are killed. It doesn't depend on where the shell hit. It could hit in MG and kill the driver, it could hit the driver's hatch and kill the MG-er.

Exact result for 71.68deg (73deg minus 1.32deg for shell descent angle) is: 34.2mm for APBC formula. Here you have a properly calculated range of 0 to 85deg using above formula and proper F and G values for each angle. Input values: D=76mm, T=25mm, Quality 100%. For APBC Angle Result 0 24,81 5 24,77 10 24,89 15 25,25 20 25,88 25 26,82 30 28,08 35 29,61 40 31,29 45 32,87 50 33,86 54 33,73 55 28,24 59 27,18 60 26,30 65 26,66 70 31,25 75 44,48 80 82,13 85 214,97 There is some range (50 to 60deg for APBC) where the T actually decreases, when angle increases. I do not believe that increasing the angle could give les protection everythibg else being equal so it is probably some error between 50 and 60deg... For APCBC and APC Angle Result 0,0 24,7 5,0 24,6 10,0 24,7 15,0 25,1 20,0 25,8 25,0 26,9 30,0 28,5 35,0 30,7 40,0 33,7 45,0 37,7 50,0 43,0 55,0 48,4 60,0 58,6 65,0 71,8 70,0 84,9 75,0 111,4 80,0 145,7 85,0 189,8 A graph for the AP & APCBC formula gives nice curve, with ends of the angle ranges almost connected (small inconsistence at 55deg). APBC formula (red one) is not so nice, there is inconsistency visible and a region where increasing the angle reduces the effective protection.

Kauz: I took a look into The Source The values of F and G coefficients are valid only for given range of angles like 55 to 60deg. So it's pointless to plot results from 0deg to 90deg for this function using fixed F and G. You should combine your 0-90deg plot from parts using corrent F and G coefficients for each given range of angles. Only then it can be determined if the formula gives credible results or is it bogus.

costard - there is no additional layer of detail the game has to "track" to be able do track&damage calculations. The knowledge of the "tank internal organs" is needed ONLY when a vehicle is penetrated, which happens very rarely in "game" terms - once in thousands of frames on average. Only then game has to calculate the shell track and check against some table of boxes and spheres - if the shell has hit any of them. If there is no penetration, this is not needed, not called and does not slow down the game at all. It may only increase game RAM memory usage by some additional, small amount (those rarely-used tables has to be kept somwhere). So adding this "additional layer" does not slow the game at all in all game frames where no penetrations happened on the battlefield. It's not a philosophy, it's coding. Knowing how code works helps to understand which things are CPU-heavy and slow down the game, and which are not.

Adding to discussion - the final angle of trajectory for a 76mm APBC shell fired from ZIS-5 gun at range of 1500m is minus 22 mils so about minus 1,32 deg (data from Russian ballistic tables).

Calculations of that kind - tracking the trajectory of the shell inside a tank and determining what module has been hit - are not especially CPU-consuming, and what is much more important - they are not calculated 50 times per second in every game frame, but are triggered rarely - only when some AP shell penetrates some armored vehicle. Only then a calculation taking 0.01s is needed. The main problem here is not CPU power, but the fact that new collision-handling code would have to be written and tested, and a database of internal parts (engine, ammo, crewmembers, gearbox, fuel tanks) would have to be created, each one having several parameters (position in tank, size, shape, ect). For each tank. It's lot of work. The current code is quite universal - it can handle any tank - when adding new one, you only put there a number of crewmembers, list of modules that can be damaged, maybe a coefficient or two (for tank size or something like that) and that's all. With a shell tracking, adding new tanks would require more work - creating a database of positions of all internal modules.

I read accounts where gunner or some other crewmember was so concentraded and pumped with adrenaline that he didn't NOTICE a penetration that wounded other crewmebers - and continued to perform his duty, but I suppose it was not a "major" penetration (like someone called it). I also read accounts where after penetration everybody or part of the crew were so shocked that they FORGET they are in tank and fighting, that there is enemy outside that continues shooting - only they wanted to escape, checked if they are ok or if their teammates are ok, and only after some time (several seconds) they were able to either evacuate from tank or get back to their stations and continue fighting, someone had to rally them and get them back to work. Yes, gunner can "forget to shot". Suddenly all hell breaks lose and the survival is most important thing, the only thing. Remember the Panther aiming at the Pershing in Cologne, with shell in the barrel ? The gunner had his foot on the firing pedak, and only waited for the American tank to stop. But Americans fired on the move, penetrated the Panther and Germans never shot. IIR the gunner survived to tell this, or maybe some other crewmember. And we are not talking about situations where the gun is already aimed and shell loaded. OK, I believe in good percent of cases the gunner of penetrated tank WOULD still fire the shell, if he survived. But there is lot of other combinations - gun is aimed but the shell is only being loaded, the penetration occurs that causes loader to drop and shell and check if he is ok and if tank is not burning. The shell is loaded but the gun is not aimed yet, and the gunner momentarili loses his consciousness from the penetration effects, even for 2 seconds. It would take time for him to recover and remind what he was doing, and possibly first to check if he is ok and if tank is not burning, ask the commander what to do ect. In CMx2 often one tank has the advantage of the first shot and penetrates other tank who didn't see the attacker - and only then the penetrated one spots (instantly) the shooter, quickly rotates turret and engages the shooter before he manages to reload and fire second time. And this way the ambushed tank often wins -with a bit of luck destroying the ambusher with first shell, before ambusher reloades for second shot. Do we really think that after major penetration of the crew compartment (flash, bang, shrapnel and sparks flying everywhere, overpresure, flame, smoke) the crew is able to quickly locate the shooting tank, rotate the turret, load the shell and aim precisely in time as quick as fully operational crew ? Everyone (commander, gunner, loader) are ok and not shocked and operate like cyborgs without any moment for recovering, understanding what happened and if it's still safe inside ? How they communicate with possibly broken eardrums and eyes blinded for few seconds by the flash of the penetration ? I can tell from reading many, many tanker diares (all I could find, and still looking for more) that in 80-90% of cases the first thought of the surviving crewmembers of penetrated tank was "...I live! should I escape?!?" "Is the tank burning yet and exploding in 5 seconds ??? I do not want to burn alive!" Second thought could be about his state (am I ok?) and state of his mates, if they are ok - maybe they need help. Sometimes - a reflexion about a decapitated friend laying on the floor and blood everywhere. Only then they would think about if the tank is ok and maybe they should return to their duties. Sometimes there is no thinking at all - there is the hit, and then people just suddenly find themselves outside of the tank, looking at the smoldering tank and not remembering how did they get out from it ! And suddenly notice those burns or this severed leg or lack or an arm... There is 10% cases where people acted differently (even didn't notice, or noticed but heroicly continued the fight) but the big majority would act about that like I described. So I really think that a penetrated tank crew (some or most of them, randomly) should get a random 0-5s or 0-10s time of "inability" that would froze their actions (commander does not spot, gunner not aims, loader not loads ect). Only after that time they would recover and continue shooting. The probability of the "shock", it's strength (length), how many crewmembers are affected, could be based on some factors like energy of the penetration, energy of the burster charge (if it went off), and especially on number of killed and wounded crewmebers - and of course highly randomised then. Stronger the penetration, greater chance for stunning the crew, and also I think that if for example 2 crewmembers were killed (maybe in a gore way) and 1 wounded there should be greater chance for strong "shock" effect than if there were no serious casualties.

Opening shots of AAA firing into buildings show much higher shell spread than seen in CMRT. AA flaks would be more effective against infantry and even against tanks if they didn't hit with all the shells in a single point.

I'm sorry but I'm just doing massive amount of tank penetration/damage/destroying tests and I see the damage done by the killing shell. One moment the tank is 100% operational and undamaged, second moment (after penetration) the tank is "destroyed" and has various amounts of damage to tracks, engine, optics or something else. So the game UI definitely shows the damage done by the killing shell. If it doesnt' show all, this should be corrected. The cases where there is no damage and tank is destroyed are of course rare, but they happen too. There are also cases where there is almost everything damaged on tank (engine, tracks, optics, main gun, weapon controls ect) and it is still NOT destroyed, so the "destroyed" state seem not connected with systems damage state. I wonder what else in tank can be damaged, that is not displayed, but decides about destroying. That steel frame that mounts everything ?

I've seen a shot hitting the ground near the barrel without a reason (nothing disturbed the firing tank). So in your case it _could be_ just a coincidence. At 1000m after 1-3 initial missed shots (range estimation), for nearly any gun every next shot are all on target. It's ok, the technical accuracy of almost any gun permits that, and the range is set correctly now. But even in such situation (3th or 4th shot to the same target) SOMETIMES the shell my miss - my test tank was putting round after round accurately on test target and suddenly next shot went into the ground 100m ahead of the muzzle. **** happens ;-) and this is simulated too ;-).

"Where I'm saying you're in error is the assertion that the fuze for German AP shell routinely detonates a 0.5-1m inside the fighting compartment. As the quotes show, at longer ranges, at least, even a partial penetration into the fighting compartment was sufficient to trigger the fuze and wreak havoc on the struck tank and crew. " Now I understand . The 0.5-1m was just an rough estimate how far a fast-flying shell could go inside of tank before the fuse works - of course this distance would be different with different terminal velocities, in many cases a slow shell could detonate just centimeters after entering the crew compartment. The actuall distance is not really importans as long, as it's not more than width of the tank . I only wanted to say that there had to be some minimum reation time after the fuse was triggered, needed for the spring to relax and for the firing pin to move and strike the cap. There were instances of German shells detonating INSIDE the internal over-the-track fuel tanks of T-34 tanks, with catastrophic results. Shell came trough over-the-track armor, got inside the partially-empty fuel tank and detonated inside. If the shell had average or large burst charge, it usually exploded the fuel fumes blowing up the fuel tank and destroying the whole tank... On the other hand, if a 75mm PzGr with only 17g of HE detonated inside a full fuel tank, it would set the tank on fire but the fluid would actually help absorbing some of the blast and shrapnel. A description of a VERY interesting test here: http://tankarchives.blogspot.com/2013/07/gas-tanks-fires-and-explosions.html edit: the "working times" for firing pin assemblies in firearms seem to be in order of 2-20ms. M-16 assault rifle firing pin works in about 5ms, a good fine-tuned firing pin assembly can be less than 2ms. Let's calculate how far a shell could fly in that time. Fastest 1000m/s shell can only move 1m per 1ms . If we assumed that speed of Pzgr39 firing pin was similar to some quick rifle firing pins (so in order of 2ms), then a fast shell that has penetrated some light armor and slowed down to let's say 400-600m/s could cover 0.8-1.2m in 2ms time of 2ms. If the shell after penetration slowed down to only 100m/s then it could go only 20cm in 2ms time. So barely penetrating shells could easily detonate just after entering the tank interior, fastest one could cover about 1.5m inside, before detonating.

I have identical observations and also feels it's not right. The number of casualties after front hull penetrations is low, the number of wounded crewmembers - ridiculously low. Higher energy guns like 88L71 or 122mm AP produce average number of casualties and have high chance for vehicle knock-out, lower-energy shells like 75L48 very often don't cause casualties at all, and often need many (2,3,5,7) penetrations to destroy a tank. One of things that needs improvement is also lack of any "shock" state for crew of penetraded vehicle. As Hpt. Lisse wrote - very often after penetration of enemy tank, it quickly returns fire just like nothing happened. Only if the penetration causes a "panic" state for the enemy crew, they do not react effectively, but panic state after penetration is not happening often. In other cases the fact that vehicle was just penetraded and some crewmembers killed/wounded, damage done, don't slow down crew reaction time and effectivenes. A high chance for crew to be "shocked" for few seconds after penetration (not responding for a moment, untill they recover) would be a good addition, IMO. I'm currently in the process of testing the casuality rate in various combinations of guns and target tanks, I have lots of interesting observations, but don't have enough data yet for various vehicles to write a raport. I'll post it here when it's finished. But I can already say, that many combinations of shell vs tank produce much lower casuality rate than both common sense and historical data would suggest. The tank in CMx2 seem to be divided into hull and turret sections, each one has it's crew and list of damage-able systems assigned to it. When shell penetrates then casualities and damage are randomly-chosed mainly from the hit part (hull or turret) and there is some chance for casualities and damage from the other part. For example, if the hull is penetrated, then there is a chance for killing some crewmembers from hull battlestations and damaging some hull systems - but who gets killed and what get's damaged is random, it's not based on "where the shell hit". If the shell hits the driver's hatch and goes trough his seat, there is still random chance that either driver or hull machinegunner would get killed. Same for damage - random - shell may pass under the turret or trough the front part, and damage the engine. If the shell hit from the side, right under the turret, trough the lower bodies of turret crew, it usually won't hurt the commander, loader and gunner and instead it will kill the driver or MG-radio-man (or both). There is also a chance (but much smaller) than someone from the other part of the tank (turret) gets killed, and that some turret system get's damaged. The tracks - although assigned to the hull - may get lightly damaged (and usually gets damaged) during almost any penetration. Same for optics. Wounded crewmembers seem to be chosen from the whole crew, not based on where the shell hit (hull or turret). But there is VERY low average number of wounded, several times lower than number of casualties. Sometimes the shell can cause ammo or fuel to detonate, penetration causes a great explosion and everyone is dead (but not much tanks systems are damaged) . How much crewmembers become casualities is random, but it's somehow depends on the energy of the shell remaining after penetration and maybe shell calibre. High energy guns like 122mm AP or 88L71 penetrating thin side armor of tanks cause on average high number of casualties, lower energy guns (like 75L48) cause low or very low number of casualties. High energy guns that penetrate strong frontal armor also may result in low numer of casualties - seems than the remaining shell energy was low and the game calculated low chance for someone being killed/wounded. Chances for vehicle becoming "destroyed" by a penetration and chances for catastrophic ammo explosion also seem depend on same factors as above (remaining energy of the shell that penetrated?). 122mm AP hitting PzIV side hull cause guaranteed vehicle kill and high chances for explosion. 75L48 in same situation cause low chances for both. If the penetrations sets the tank on fire, the (surviving) crew obviously gets off instantly. In the other case they can choose to stay in the (destroyed) tank for random amount of seconds (from 1 second to something like 20 sec), especially if they are not panicked. The tank is listed as destroyed and they do not fight, they do nothing, but stay inside. I wonder what makes this tank so "destroyed" if all the tank systems are operational and it's crew is not panicked .

Thanks for the very interesting article. Again the effectivenes of PzGr39 fuse is mentioned. I'm not sure about what incorrect info you said. If it was about the phrase "high explosive filler with a delay fuze" in the article, then the phrase is most likely incorrect. I'm not sure what kind of fuse the 7.5 cm K.Gr.rot Pz had, but all the PzGr39 type shells had mechanical "decceleration-lack of decceleration" fuse, and NOT a "time delay fuse". I need to mention that the 7.5 cm K.Gr.rot Pz had a very larhe HE burst charge, 80g of HE. Charge of this size - seem from the article - has disastrous effects. Later 75mm Pzgr39 had much smaller charge of 19g and were less deadly, although the charge still increased their effectivenes. 88mm PzGr39 shells had much larger burst charge, comparable to the one of 7.5 cm K.Gr.rot Pz. Time delay method was probably worse, because it was hard to set one single delay time that would be correct in all situations. When the shell was penetrating with great excess of penetration power and retained most of it's initial speed inside of the vehicle, too long delay would cause it to detonate too late, when it gone trough the other side. On the other hand, a short delay time would not work in cases when shell barely penetrated, the penetration process was long and the shell "almost stopped" during the process. It would most likely detonate during the penetration of armor, then. Fine tunning this delay time to work well in most cases, was something than not all nations managed to achieve during the war. Some types of time fuses tended to go off too early, destroing the shell when it was still penetrating, some other may have detonate too late, when the shell gone completly trough the tank (especially in cases of tank side armor penetrations - when high shell speed was retained).

In German shells it was not fixed delay fuse, but instead a "gone through" detector. It was armed at launch, then triggered by sequence of great decceleration followed by lack of decceleration during penetration of armor. As soon as the shell penetrated and entered the interior of the vehicle, the spring in the fuse was released and the charge detonated. Not sure how far it could fly behind the armor in the time the spring moved, but probably it was in order of half a meter to one meter, depending on shell speed. The minimal thickness of armored plate that would trigger the fuse was about 20mm (or little more). The fuse was said to be very effective and reliable. On the other hand, it was a mechanical solution that could malfunction (especially if mass produced with poor materials by slave workers) and it tended to fail after penetration of highly sloped armor - the enormous side acceleration experienced by the shell caused some moving parts inside the fuse to get stuck/jammed and the fuse didn't work. Other nations fuses used a simple fixed time-delay IIRC. Not always timed correctly, sometimes they tended to detonate during penetration of the plate.

The 17 pounder gun was also excellent tank killer, even though it's shells lacked the burst charge. High percentage of German tanks penetrations, especially from the side, resulted in instant explosion of the hit tanks. The kinetic energy of the penetration was usually enough, because the shell usually penetrated with great excess of energy and entered the tank interior at high velocity. Of course adding a burst charge would make it even more lethal, especially in cases where it barely penetrated. 75L70 had little less energy than 17pdr, but the shells had a small bursting charge praised for it's effectiveness. 88L71 had both greater velocity, greater energy and quite big burst charge. Penetrations by this gun had to be awfully lethal... Same for Russian D-10T 100mm gun - high velocity, big kinetic energy and a burst charge. The 122mm D-25T gun had average velocity, but greatest kinetic energy, and a huge shell with big HE burster.