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#1 Mark Serafin

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Posted 12 February 2007 - 12:33 PM

So, yesterday we played Java Sea, and of course some rules questionscame up. I already posted these questions to the yahoo group, but I'm always interested in getting plenty of opinions (until I find one I like!):1. Spotter aircraft. Ships spotting aircraft up fire down onerange band on the gunnery chart. At what point do these ceasehaving an effect? I had Japanese heavy cruisers claiming thisbenefit while shooting at destroyers in the 6000 yard range band. Iwould think that at some point the guy at the director station wouldhave a better shot through direct observation rather than listeningto the airplane spotter. And yet the rules say nothing about it.Did I miss something?2. Torpedoes. Java Sea canbe described (from the ABDA point ofview) as "running barefoot through the Long Lance." Whilst tryingto do this we came up with something that is an effective tactic bythe rules but completely ignores reality. To whit, the Alliedcruiser line was +/- 50cm from a line of Japanese DDs, who were ofcourse launching torpedoes. They did not reach the targets in theirfirst turn of movement. What we figured out is that, by the rules,if the Allied cruisers had turned into the torpedoes and movedcloser to their launch point than 45cm, there would have been nochance for a hit. The torps would be looking for targets in the 45-90 cm range band, so if the cruisers closed to less than 45cm, therewould have been no chance. Essentially they would have been ableto 'leap over' the torpedoes. In the end we didn't do it because wethought it impossibly cheesy, but by the rules it would haveworked. Again, did I miss something in the rules (other than theadvanced torp rules, which we aren't using yet, this being oursecond game).3. Long Lance don't seem to hit with muchmore power than regular21" torpedoes, despite having a warhead about 50% larger. There area few points in the IJN torpedo effect chart that are different thanothers, but the differences aren't nearly as big as one gets byusing torpex-headed fish. Any ideas/explanations as to why? Notthat the LL needs to be any more of a pain...Thanks for any help!

#2 Dave Franklin

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Posted 12 February 2007 - 05:52 PM

I haven't looked on Yahoo to see what replies you've already received there, but here is my take:1. As written, there is no minimum range, as a ship that normally would not benefit (i.e. is already on the lowest row, the range being under 6000 yards) could still benefit to offset an "up 1 row" mod.2. Your observation is correct. I would suggest when one side is determining if their torpedoes have a chance to hit, you have the target side look away or leave the room (yes, this takes more time). Then if a target player has the savvy to guess right and move inside the torpedoes, you have two choices: a) tip your cap to him, or b) resolve it as a possible hit.3. I admit to examining the IJN torpedo damage table myself, and being surprised there wasn't more of a difference between it and the other navy's.

#3 Lonnie Gill

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Posted 16 February 2007 - 09:55 PM

"Running barefoot through the Long lances" - evocative, but not a pretty sight! Now that the PC is up and running again, here's my response to some good questions. 1. Certainly, there is a point of diminishing returns where aerial spotting does not convey any real advantage over director spotting. The GUNFIRE CRT shows that to be at 6,000 yds. When you're in the 9,000 yd range band (6,100 - 9,000 yds) Air Spot still enables you to shift down one row; but once you reach 6,000 yds or less, you are at the bottom of the table and can't derive any additional advantage. Further, you'll note that most capital ship batteries - which had the most sophisticated fire control and longer base optical rangefinders - do not derive any benefit when they're in the 9,000 yd range band as the "to hit" probability is the same as the lower 6,000 yd row. Thus, the minimum benefit limit for air spotting is built into the CRT.2. Good comments on torpedo resolution. The basic system streamlines and simplifies a complex simultaneous movement situation by measuring torpedo and target location only at one point in the Game Turn, i.e. after movement. In most situations, this works fairly well and saves a lot of playing time - and helps offset that it's much easier to intercept a miniature in a game at attenuated "scale ranges" than it is to hit a target at actual scale ranges on a big ocean. But, this simple approach doesn't deal adequately with the "step over the range band" circumstance you describe. There are two ways to deal with this special situation: a) You can pro-rate movement that Game Turn, as described in Optional Rule Section 1.4.9 on page 5-1, or b) you can consider it an interception if the course of the target vessel crosses the torpedo spread's LoF at any point in the Game Turn while moving into the torpedo spread's "previous" range band. Both approaches require more time to resolve. Depending on the intensity and sophistication of your simulation, you can decide on method b) which is a bit quicker or method a) which is slower, and requires precise fidelity while moving, but more accurate. I think you will find the basic system provides a reasonable simulation for all other conditions.3. Several comments on the IJN's Long Lance torpedo. First, the Type 93's warhead at 1080 pounds was bigger, but not 50% bigger as often related, than the warhead of the USN Mark 15 (825 pounds) or the RN's Mark IX (810 pounds) for example. Thus, there's a difference, but not as pronounced as often thought. With a simulation system utilizing a limited number of Hull Boxes, small changes can have a pronounced effect. Hence, I took a fairly conservative approach to reflecting the effect of the Type 93's larger warhead. The end result corresponds with historical experience in the Solomons, etc. One hit will probably badly damage, but not sink a cruiser, while a second is highly likely to be more than enough. One hit will probably cause major damage to a CV or BC and significant damage to a larger BA or BB. I admit that I was "on the cusp" of increasing the effect in several parts of the table and that others may want more distinction. There's not enough historical evidence to determine this conclusively. No Allied BA or BB, for example, was hit by a Long Lance; but the USS North Carolina took significant damage from a smaller warhead submarine torpedo hit in the Solomons. Second, Torpex, with 50% more explosive power, gave the 800+ pound American and British torpedo warhead a great deal more effect than their standard warheads and more power than the Long Lance as well. Among the various navies, there was a considerable variation in warhead weight and explosive power per pound. In the interest of streamlining play, I broke this spectrum down into several categories: smaller 18" and aerial, the typical 21", Long Lance and finally the late war Torpex warhead. If this is an area you and your group would like to simulate in more detail, you can alter the CRT. I would be interested in your proposed changes.

#4 gregoryk

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Posted 17 February 2007 - 08:43 AM

lonnie wrote:

"Running barefoot through the Long lances" - evocative, but not a pretty sight! Now that the PC is up and running again, here's my response to some good questions. 3. Several comments on the IJN's Long Lance torpedo. First, the Type 93's warhead at 1080 pounds was bigger, but not 50% bigger as often related, than the warhead of the USN Mark 15 (825 pounds) or the RN's Mark IX (810 pounds) for example. Thus, there's a difference, but not as pronounced as often thought. With a simulation system utilizing a limited number of Hull Boxes, small changes can have a pronounced effect. Hence, I took a fairly conservative approach to reflecting the effect of the Type 93's larger warhead. The end result corresponds with historical experience in the Solomons, etc. One hit will probably badly damage, but not sink a cruiser, while a second is highly likely to be more than enough. One hit will probably cause major damage to a CV or BC and significant damage to a larger BA or BB. I admit that I was "on the cusp" of increasing the effect in several parts of the table and that others may want more distinction. There's not enough historical evidence to determine this conclusively. No Allied BA or BB, for example, was hit by a Long Lance; but the USS North Carolina took significant damage from a smaller warhead submarine torpedo hit in the Solomons. Second, Torpex, with 50% more explosive power, gave the 800+ pound American and British torpedo warhead a great deal more effect than their standard warheads and more power than the Long Lance as well. Among the various navies, there was a considerable variation in warhead weight and explosive power per pound. In the interest of streamlining play, I broke this spectrum down into several categories: smaller 18" and aerial, the typical 21", Long Lance and finally the late war Torpex warhead. If this is an area you and your group would like to simulate in more detail, you can alter the CRT. I would be interested in your proposed changes.

Lonnie's explanation coincides with much of the in-depth research I have read. The Type 93's advantages were:[ol][li]reliability — when it hit something, it detonated[/li][li]range — most of its long length was propellant[/li][li]warhead size — though it was not so much larger than other navies' torpedoes[/li][/ol]It ran straight and true, fast and far, and blew up on contact. American torpedoes would have had much greater success in the early war years if they could only have done the same.Gregory

#5 Mark Serafin

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Posted 21 February 2007 - 04:20 PM

1. Certainly, there is a point of diminishing returns where aerial spotting does not convey any real advantage over director spotting. The GUNFIRE CRT shows that to be at 6,000 yds. When you're in the 9,000 yd range band (6,100 - 9,000 yds) Air Spot still enables you to shift down one row; but once you reach 6,000 yds or less, you are at the bottom of the table and can't derive any additional advantage. Further, you'll note that most capital ship batteries - which had the most sophisticated fire control and longer base optical rangefinders - do not derive any benefit when they're in the 9,000 yd range band as the "to hit" probability is the same as the lower 6,000 yd row. Thus, the minimum benefit limit for air spotting is built into the CRT

Ah, but for heavy cruisers the cut-off is only 6,000 yards when shooting at another cruiser. When shooting at DDs, the 8" is up one band to 9,000, then back down to 6,000 because of the spotting aircraft. I would think the aircraft spotting would be least effective against fast-moving DDs, particularly when they get in close (and the 8" probably have trouble tracking them as targets). I suppose this falls into the 'no rules can cover everything' area, but it seems to give spotting aircraft way too much effect, more than I've ever read about.

#6 Cpt M

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Posted 24 February 2007 - 01:47 PM

semonyenko wrote:

Ah, but for heavy cruisers the cut-off is only 6,000 yards when shooting at another cruiser. When shooting at DDs, the 8" is up one band to 9,000, then back down to 6,000 because of the spotting aircraft. I would think the aircraft spotting would be least effective against fast-moving DDs, particularly when they get in close (and the 8" probably have trouble tracking them as targets). I suppose this falls into the 'no rules can cover everything' area, but it seems to give spotting aircraft way too much effect, more than I've ever read about.

The presence of an aerial spotter when used when firing on a DD corrects the fall of shot and, in essence, corrects any ranging errors. The impact is to nullify the DDs target size advantage. BTW, this effect applies at all ranges, so in your example (firing at 6000yds), it would be correct for the solution to remain on the 6000yd line. (BTW, the above is based on USN doctrine for the use of aerial spotters. The USN, like others, spent an extraordinary amount of time and money on developing aerial spotting during the '20s and '30s).Regarding the ability of an 8" battery to track a DD at close range: The training rate of the slowest main battery of this period was around 2 degrees per second (this applies to even the Yamato's 18" triple turret). Given the turn length, a turret with a 2 degree rate of train could sweep a full 360 degrees, which, at a range of 6000 yds, means sweeping a circle with a circumference of over 37000yds. A DD, moving at 40kts will cover only 4000yds. And given that many of the later turret designs had training rates of 4 to 6 degrees per second, and all were linked to state-of-the-art fire control systems (which were designed to track aircraft as well as ships), I think we can dismiss this long standing gaming myth.What does have impact is the size of the target relative to the impact area of the larger guns and their rate of fire. The area covered by the straddle of the larger shells is significantly larger than that of smaller shells (6' and below). Any reduction in lethality is due to the smaller footprint of the target (the average DD) and the lower number of potential shells striking (due to the lower rate of fire). In reality, the difference between the various calibers should be on sliding scale, but that would be impractical for gaming purposes.

#7 simanton

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Posted 13 March 2013 - 06:26 PM

Whoa! Is this THE Mark Serafin, ex Seapower player of Glen Ellyn, IL?




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