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Post by abclark on Dec 30, 2018 15:24:28 GMT -6
Continuing the discussion going on in the Pre-Release Discussion thread without further cluttering it: 1) Did Japanese guns train to very high elevation or was it just an ammo modification? 2) Is there another thread for this? Japanese cruiser and battleship gun do not have a higher elevation than any other comparable contemporaries and generally have poor train rates, which is partly why they are practically useless as AA weapons. Giving battleship caliber gun superior train rate and extremely high angle fire is a far more complex issue that I don’t think 25% more weight adequately captures. (Notably the issue with reloading from a high angle, and firing the gun at a very high angle) To be fair if the team decides to let any gun dp with a 25% weight increase I will not have an issue with it,(provided high caliber gun is ineffective as they would be) just don’t think it will be something worth the effort to implement(as is my thought with san-shiki). But yes in any case if this disscusssion goes on it might be a good idea to take it to a different thread. I have to take exception to IJN cruisers not having high elevation limits. All their heavy cruisers of the Takao class and later had a maximum elevation of 55 degrees (most of the Takaos could elevate to 70 degrees, but it could damage the mounts). That’s 14 degrees higher than the USN standard, 18 degrees higher than the Admiral Hipper class, and only really equaled by the RN, with either 50 or 70 degree elevation limits. Their 6” armed cruisers weren’t particularly better than average, but they still could elevate to 55 degrees. I agree that they had poor train rates, especially compared with a true DP mounting like the US 6”/47 mount on the Worcester class, which had a pretty spectacular 25 degrees per second. But at long range, the only possibly practical range for 8” AA fire, rate of train would be less important. Rate of elevation and loading angle (which would affect effective rate of fire) would be much more important. I also agree that a 25% weight increase isn’t enough for large caliber guns. The two gun turrets of the Worcester class weigh considerably more than the triple turrets of the Cleveland class. Perhaps a gradually increasing weight multiplier to go along with increased caliber would be a better route. As far as gameplay goes, I can see large caliber (probably 6”-8”), automatic loading DP guns being effective late in the game. They could seriously increase the distance at which aircraft could be engaged, which is a big deal against fast aircraft which normally reduce the amount of ordnance that can be thrown at them due to lower exposure time. |
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Post by axe99 on Dec 30, 2018 18:22:26 GMT -6
I'm not sure why it waited until now to pop into my head, but iirc the most common use of large-calibre AA was by the RN, and was used using 'barrage fire' - they developed specific barrage-fire radars to support that kind of thing. The ships didn't need super-high elevation, as the barrage was usually either in the distance and/or over surrounding ships. It's, as ever, from hazy memory, but I think the largest calibre used may have been Nelson's main armament using Operation Pedestal, although I'd like to look that up and be sure before anyone placed too much weight on it (that said, there's no question the Japanese used their BB main batteries for similar roles). This was a way around the slow elevation and train rates (which, as noted, made the larger calibre weapons ineffective for following a target) and the barrages were generally a 'one shot' proposition.
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Post by abclark on Dec 30, 2018 19:15:32 GMT -6
To add a little data to the discussion, I calculated the train rate required to track an aircraft orbiting at 5000 yards at 300 mph. That would only require ~1.7 degrees per second. That’s even one of the worst possible shots that could be required of such a gun, since most aircraft are going to be flying at something other than a 90 degree angle to the ship.
Of course, that doesn’t help with the other issues like low rates of fire at high angles (and in general).
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Post by rob06waves2018 on Dec 30, 2018 19:22:38 GMT -6
In my tactical opinion, elevation past a certain point is no use. Up to, say, 60 degrees is useful as one can engage targets closer and higher. However, any greater elevation and you're just firing at something that got too close and one cannot track the target effectively at low altitudes. In effect, the AA battery has failed.
By the same token, it was possible to engage an aircraft at low elevation a long distance away. However, a more powerful gun would be required to reach this distance.
In conclusion, I think all guns should be able to be DP but in separate research for <6" and >5". The smaller calibres would depend on higher elevation to become DP but the higher calibres would depend on a range of factors (radar, range, ammunition etc.).
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AiryW
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Post by AiryW on Dec 30, 2018 21:26:02 GMT -6
In my tactical opinion, elevation past a certain point is no use. Up to, say, 60 degrees is useful as one can engage targets closer and higher. However, any greater elevation and you're just firing at something that got too close and one cannot track the target effectively at low altitudes. In effect, the AA battery has failed. Surely there is a point at shooting at dive bombers when they are in the dive. At the very least it makes it more difficult for the pilot to aim. |
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Post by oldpop2000 on Dec 30, 2018 21:47:00 GMT -6
In my tactical opinion, elevation past a certain point is no use. Up to, say, 60 degrees is useful as one can engage targets closer and higher. However, any greater elevation and you're just firing at something that got too close and one cannot track the target effectively at low altitudes. In effect, the AA battery has failed. Surely there is a point at shooting at dive bombers when they are in the dive. At the very least it makes it more difficult for the pilot to aim. See a later post for accurate information |
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Post by mycophobia on Dec 30, 2018 23:39:14 GMT -6
Thanks for the correction with regard to Takao class, I presumed the aa refit some of them underwent was mostly for additional light mounts and director/radar, didn’t not knew they were capable of such high elevation as well.
I agree that elevation/train rate are not necessarily crucial for engaging in long range fire , but I do note that in practice, without radar and prox fuse, the performance of these long range AA fire is atrocious. (Some Japanese report claim they are highly effective, but I almost think that’s because they mistaken type-3 shell’s inciendairy trail for downed plane, the numbers given by japanese are often grossly exaggerated)
With proper fire guidance/prox fuse it is probably feasible for cruiser caliber guns to serve as long range aa artillery, but volume of fire is still likely more important. Correct me if I am wrong but I don’t believe 50s radar fire control allow for the degree of precision required to engage aerial target from a distance significantly further than the range of 5-6in dp guns. As caliber increase, the number of shot a battery can get off before the plane is close enough to be in the dead zone of the aa reduces. Thus I feel the usefulness of these high caliber dp gun decrease sharply, to the point that battleship caliber ones are basically useless.
My original point is mostly focused on questioning the practicality of battleship caliber AA but I think the focus now is more on the cruiser level dp of about 8in. In that case I feel that definately can be viable within game’s technology frame, but will require specific accomodation in ship design which may not render it effective(but I do think can be a reasonable inclusion for the game for sure)
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Post by corsair on Dec 31, 2018 0:26:38 GMT -6
Surely there is a point at shooting at dive bombers when they are in the dive. At the very least it makes it more difficult for the pilot to aim. In the Pacific War, the early dive bomber attacks were made at 60 degrees with a release at about 1500 feet depending on how brave the pilot was. Later in the war, it was found that the glide bomb, at 30 degrees was the safest. The best air defense is to attack the dive bombers from other ships, in a cross fire. The best defense was guns of around 40 mm or 20 mm, 5 inch would be ok at firing at aircraft just starting their dives. The best defense is fighter support. As I recall, at least earlier in the war, the Japanese dove at an angle of about 55° whereas USN dive bombers dove at angles closer to 70°. As to glide bombing, that was easier for pilots to do than dive bombing, but at the cost of lower accuracy. |
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Post by aeson on Dec 31, 2018 1:41:53 GMT -6
Surely there is a point at shooting at dive bombers when they are in the dive. At the very least it makes it more difficult for the pilot to aim. Starting with no initial vertical velocity, neglecting air resistance, and assuming an unpowered vertical fall, it only takes about thirty seconds to drop 15,000 feet. Alternatively, it takes about 40 seconds to travel 15,000 feet at 250 miles per hour. As a ballpark figure, then, you have no more than about 30-40 seconds from when a dive bomber pushes over to when it releases its bomb to set the fuse, load the gun, elevate the gun from its maximum loading angle to whatever angle you need it to be at to engage a dive bomber diving on your ship, and fire. If you don't have proximity fuses, an automatic fuse setter which receives range information directly from whatever rangefinders you're using with the minimum operator input possible, or a system like the British programmed barrage, a relatively heavy gun like an 8" simply isn't going to be able to engage a dive bomber diving on the ship carrying the 8" gun, and even with that kind of stuff you'd be lucky to get off more than one or two shells with most of the 8" guns used on historical heavy cruisers, at least until you get into fully-automatic any-elevation loaders with automatic fuse setters and proximity-fused shells. Even the more typical interbellum and WWII-era heavy AA guns had issues engaging aircraft once they got in close.
If you want to harass dive bombers diving on your ship once they've already pushed over, light and medium AA guns are what you're looking for. Heavy AA guns are for engaging aircraft at relatively long ranges, where the typically-lower elevation, training, and fire rates of the heavier guns don't matter so much.
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Post by oldpop2000 on Dec 31, 2018 10:05:07 GMT -6
In the Pacific War, the early dive bomber attacks were made at 60 degrees with a release at about 1500 feet depending on how brave the pilot was. Later in the war, it was found that the glide bomb, at 30 degrees was the safest. The best air defense is to attack the dive bombers from other ships, in a cross fire. The best defense was guns of around 40 mm or 20 mm, 5 inch would be ok at firing at aircraft just starting their dives. The best defense is fighter support. As I recall, at least earlier in the war, the Japanese dove at an angle of about 55° whereas USN dive bombers dove at angles closer to 70°. As to glide bombing, that was easier for pilots to do than dive bombing, but at the cost of lower accuracy. I went to my SBD manual and did some research. A dive bombing attack was made from the vertical or 90 degrees. The diving angle chart in the manual shows this with a nose angle of -5 degrees, there are two curves, one based on flaps down and one with flaps up. The idea was to approach the target with it being on the left side of the nose and it was initiated when the target disappeared from under the wing. There was no rudder control used once the dive started. The pilot was then push the nose over using the stick. After 10 seconds, the pilot would pull back on the stick to change the dive angle to between 60 and 70 degrees. My dad always told me that they always pulled back to 60 degrees, to reduce the stress on the SBD and ensure that the bomb cleared the prop. The 60 or 70 degree angle was the release angle only. My apologies for any previous mistakes, I just did not have time to review my manuals and get it correct. I will remember to take the extra time. World War 2 Official Naval Training Film on Dive Bombing - www.youtube.com/watch?v=lOz_i_2USkYeugeneleeslover.com/USNAVY/CHAPTER-23-E.html |
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Post by jwsmith26 on Dec 31, 2018 10:42:27 GMT -6
Surely there is a point at shooting at dive bombers when they are in the dive. At the very least it makes it more difficult for the pilot to aim. In the Pacific War, the early dive bomber attacks were made at 60 degrees with a release at about 1500 feet depending on how brave the pilot was. Later in the war, it was found that the glide bomb, at 30 degrees was the safest. The best air defense is to attack the dive bombers from other ships, in a cross fire. The best defense was guns of around 40 mm or 20 mm, 5 inch would be ok at firing at aircraft just starting their dives. The best defense is fighter support. The Japanese navy seemed to put little faith in AA protection. They separated their ships to allow room for individual maneuver and made little effort to provide additional AA support to their carriers in the form of escorting ships. They certainly put up fighters, but without effective utilization of radar, no CIC type fighter control system and little ability to even communicate with their fighters in the air, it certainly appears that they put most of their faith in radical maneuver to avoid air attack. While that compares very poorly to their opponents in WW2, it was actually the reality for most of the period covered by the game for every nation, not just the Japanese. Without radar to provide sufficient warning of incoming strikes, a combat air patrol was pretty ineffective and would have been so from 1917 through the late 1930s. During that time span the British pretty much gave up on the idea of protecting their carriers with fighters, instead building fighters that were not intended to mix it up with incoming bombers but rather were designed for long range missions over open ocean with the intent of protecting their torpedo bombers (they didn't really build dive bombers between the wars). That is why they generally were equipped with a second seat for a gunner/navigator. Their fighters were built to be a stable platform for the rear gunners who were to add their firepower to the bomber formations, while the 2nd seat also provided the ability to more safely navigate over open ocean. Of course that was the British view. The Americans and Japanese took a different view of fighters. But even in the Japanese navy there was a period in the early to mid 30s, when bombers briefly became faster than fighters, when they came to the conclusion that fighters could not effectively protect a carrier and considered abandoning carrier fighters altogether. The fighter pilots eventually prevailed when the heavy Japanese naval bomber losses to enemy fighters over China convinced them of the value of fighter escorts. I apologize for straying from the subject of AA guns, but I want to point out that the game does not just cover the 6 year span of WW2. We should guard against assuming those technologies developed during that brief period were the norm during the much longer period that the game covers. We have no wars to tell us what naval air combat might have looked like during the period between the world wars, but one thing we can be sure of is that it would have been very different than what occurred in WW2. |
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Post by oldpop2000 on Dec 31, 2018 11:04:06 GMT -6
In the Pacific War, the early dive bomber attacks were made at 60 degrees with a release at about 1500 feet depending on how brave the pilot was. Later in the war, it was found that the glide bomb, at 30 degrees was the safest. The best air defense is to attack the dive bombers from other ships, in a cross fire. The best defense was guns of around 40 mm or 20 mm, 5 inch would be ok at firing at aircraft just starting their dives. The best defense is fighter support. The Japanese navy seemed to put little faith in AA protection. They separated their ships to allow room for individual maneuver and made little effort to provide additional AA support to their carriers in the form of escorting ships. They certainly put up fighters, but without effective utilization of radar, no CIC type fighter control system and little ability to even communicate with their fighters in the air, it certainly appears that they put most of their faith in radical maneuver to avoid air attack. While that compares very poorly to their opponents in WW2, it was actually the reality for most of the period covered by the game for every nation, not just the Japanese. Without radar to provide sufficient warning of incoming strikes, a combat air patrol was pretty ineffective and would have been so from 1917 through the late 1930s. During that time span the British pretty much gave up on the idea of protecting their carriers with fighters, instead building fighters that were not intended to mix it up with incoming bombers but rather were designed for long range missions over open ocean with the intent of protecting their torpedo bombers (they didn't really build dive bombers between the wars). That is why they generally were equipped with a second seat for a gunner/navigator. Their fighters were built to be a stable platform for the rear gunners who were to add their firepower to the bomber formations, while the 2nd seat also provided the ability to more safely navigate over open ocean. Of course that was the British view. The Americans and Japanese took a different view of fighters. But even in the Japanese navy there was a period in the early to mid 30s, when bombers briefly became faster than fighters, when they came to the conclusion that fighters could not effectively protect a carrier and considered abandoning carrier fighters altogether. The fighter pilots eventually prevailed when the heavy Japanese naval bomber losses to enemy fighters over China convinced them of the value of fighter escorts. I apologize for straying from the subject of AA guns, but I want to point out that the game does not just cover the 6 year span of WW2. We should guard against assuming those technologies developed during that brief period were the norm during the much longer period that the game covers. We have no wars to tell us what naval air combat might have looked like during the period between the world wars, but one thing we can be sure of is that it would have been very different than what occurred in WW2. I quite agree with your last paragraph. I have been concerned about this. Wars, as most know, do tend to accelerate technological advancement. While the old saying is true" You won with what you brung, a long war can provide the need and time to accelerate advancements in technology not to mention the funding which is not available in peacetime. This is very true of the interwar period, because it was the war that brought the nations of the world out of the depression. I believe that it would have taken far more time without it. In this instance, necessity if the mother of invention and it is very true of wars and technology. |
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Post by corsair on Dec 31, 2018 13:06:34 GMT -6
As I recall, at least earlier in the war, the Japanese dove at an angle of about 55° whereas USN dive bombers dove at angles closer to 70°. As to glide bombing, that was easier for pilots to do than dive bombing, but at the cost of lower accuracy. I went to my SBD manual and did some research. A dive bombing attack was made from the vertical or 90 degrees. The diving angle chart in the manual shows this with a nose angle of -5 degrees, there are two curves, one based on flaps down and one with flaps up. The idea was to approach the target with it being on the left side of the nose and it was initiated when the target disappeared from under the wing. There was no rudder control used once the dive started. The pilot was then push the nose over using the stick. After 10 seconds, the pilot would pull back on the stick to change the dive angle to between 60 and 70 degrees. My dad always told me that they always pulled back to 60 degrees, to reduce the stress on the SBD and ensure that the bomb cleared the prop. The 60 or 70 degree angle was the release angle only. My apologies for any previous mistakes, I just did not have time to review my manuals and get it correct. I will remember to take the extra time. World War 2 Official Naval Training Film on Dive Bombing - www.youtube.com/watch?v=lOz_i_2USkYeugeneleeslover.com/USNAVY/CHAPTER-23-E.html
Thanks for the additional info! At what point in the dive were the dive flaps extended? I presume it was relatively early in the process. Regardless of the exact process, I think it safe to say that being a dive bomber pilot was not for the faint of heart. (It must have been interesting for the rear seat gunner as well.)
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AiryW
Full Member
Posts: 183
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Post by AiryW on Dec 31, 2018 13:17:42 GMT -6
Surely there is a point at shooting at dive bombers when they are in the dive. At the very least it makes it more difficult for the pilot to aim. Starting with no initial vertical velocity, neglecting air resistance, and assuming an unpowered vertical fall, it only takes about thirty seconds to drop 15,000 feet. Alternatively, it takes about 40 seconds to travel 15,000 feet at 250 miles per hour. As a ballpark figure, then, you have no more than about 30-40 seconds from when a dive bomber pushes over to when it releases its bomb to set the fuse, load the gun, elevate the gun from its maximum loading angle to whatever angle you need it to be at to engage a dive bomber diving on your ship, and fire. If you don't have proximity fuses, an automatic fuse setter which receives range information directly from whatever rangefinders you're using with the minimum operator input possible, or a system like the British programmed barrage, a relatively heavy gun like an 8" simply isn't going to be able to engage a dive bomber diving on the ship carrying the 8" gun, and even with that kind of stuff you'd be lucky to get off more than one or two shells with most of the 8" guns used on historical heavy cruisers, at least until you get into fully-automatic any-elevation loaders with automatic fuse setters and proximity-fused shells. Even the more typical interbellum and WWII-era heavy AA guns had issues engaging aircraft once they got in close. If you want to harass dive bombers diving on your ship once they've already pushed over, light and medium AA guns are what you're looking for. Heavy AA guns are for engaging aircraft at relatively long ranges, where the typically-lower elevation, training, and fire rates of the heavier guns don't matter so much.
You seem to be responding to a different post then the one that you quoted. Please be more careful in the future. I apologize for straying from the subject of AA guns, but I want to point out that the game does not just cover the 6 year span of WW2. We should guard against assuming those technologies developed during that brief period were the norm during the much longer period that the game covers. We have no wars to tell us what naval air combat might have looked like during the period between the world wars, but one thing we can be sure of is that it would have been very different than what occurred in WW2. That is what is so engaging about RTW IMHO. There isn't a "right approach" because the vagaries of technology and the uncertainty of the time of a conflict mean it's such a more interesting problem to think about the right approach. I tried out the Homeworld games the other day and they are quite good games but they fall into the classic RTS problem of there being "correct" progressions which you can know before you even start a game. There would never be a situation like in my current run through of RTW where wars and technologies lead me to skip past two generations of dreadnought and end up building a compromise design the likes of which I had never built before. And RTW 2 seems to offer the chance for this to an even greater extent since there are now so many more dimensions of possible variation. |
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Post by oldpop2000 on Dec 31, 2018 13:37:30 GMT -6
I went to my SBD manual and did some research. A dive bombing attack was made from the vertical or 90 degrees. The diving angle chart in the manual shows this with a nose angle of -5 degrees, there are two curves, one based on flaps down and one with flaps up. The idea was to approach the target with it being on the left side of the nose and it was initiated when the target disappeared from under the wing. There was no rudder control used once the dive started. The pilot was then push the nose over using the stick. After 10 seconds, the pilot would pull back on the stick to change the dive angle to between 60 and 70 degrees. My dad always told me that they always pulled back to 60 degrees, to reduce the stress on the SBD and ensure that the bomb cleared the prop. The 60 or 70 degree angle was the release angle only. My apologies for any previous mistakes, I just did not have time to review my manuals and get it correct. I will remember to take the extra time. World War 2 Official Naval Training Film on Dive Bombing - www.youtube.com/watch?v=lOz_i_2USkYeugeneleeslover.com/USNAVY/CHAPTER-23-E.html
Thanks for the additional info! At what point in the dive were the dive flaps extended? I presume it was relatively early in the process. Regardless of the exact process, I think it safe to say that being a dive bomber pilot was not for the faint of heart. (It must have been interesting for the rear seat gunner as well.)
The check-off list shows that A. fuel was set to main tank B. Mixture to auto rich C. Supercharger to low blower D. Propeller to max cruising which was about 1900-2200 rpm E. Cowl Flap closed F. Carburetor air to direct G. Oil cooler scoop closed H. trim tabs check I. Diving Flaps open but not in excess of 210 Knots J. Max RPM was 3100 K. Max indicated air speed was 425 mph or 370 Knots. The rear gunner would push the guns into the cavity to the rear and the doors would auto close. Turn his seat around, close his canopy. His job was to read off the altitude and speed to the pilot. One of my Dad's injuries was received coming off of a dive on a transport in Rabaul, luckily the bottom underneath his seat was armored and deflected the shell that hit the plane, unfortunately the armor plate back side splintered and send shrapnel into his legs. They were never able to get that out. |
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1) Did Japanese guns train to very high elevation or was it just an ammo modification?
