18 replies to this topic

[Jim O'Neil]

I Note that Naval Guns used on larger or smaller ships than the firing ship, get a modification. In concept this seems fine, but I considerd USS SAN FRANCISCO firing on HIEI at very close range... those 8" shells did a lot of damage, penetrating the 8" Belt into the engines and steering compartments and causing serious fires. It seems that the effect should just be modified by armor thickness, not ship size. The 8" gun is penetrating "Bd" armor at 3,000 yards/meters and cutting the effect in half because it is a BC seems odd.I would further confuse this by pointing out that the Japanese called these ships (The KONGO Class) Battleships... which would totally elimnate any damage...

[Cpt M]

The desgnator (BC, BA, CA, etc) is a rating of the ships resistance to damage and takes into account the armor level, construction and size of the ship. In the case you mention, the San Francisco would still be able to penetrate and cause full damage, including those you mentioned (and more, including a magazine explosion). Since the hull boxes are not linear (a BB hull box does not represent the same thing as a CA or DD hull box), a mechanism is needed to bring the hits inflicted by a 8" gun into the same plane as, say the hits inflicted by a 16" gun (or 5" gun). And this is what's happening in the Equivalent Hits table.While the IJN may have referred to the Kongos as BBs, their scale of armor and resistance to damage is more realistically at the level of BCs. You may have noticed that the Brooklyns, considered CLs by the USN, are given a rating of CA; their 6" guns rates them as CLs but their construction and armor were definitely along the lines of a CA. Conversely, the Salt Lake City is better rated a CL due to her light armor and construction even though she carries 8" guns and is considered a CA by the USN.

[Jim O'Neil]

I noted this... and The WICHITA and BALTIMORE Classes should be rated as BD or BC as their 6 inch class A belts and 2" plus decks are hardly CA level protection. But I suppose we should expect to have to make some of our own modifications.

[Cpt M]

Keep in mind the designation is not just the armor; it also incorporates the strength of the hull and its resistance to damage. While the Wichita and Baltimores do have a heavier belt and deck (which just qualifies within the bottom limit of BD-B* (and definitely not BC) if one looks purely at armor), this is incorporated on a treaty restricted cruiser hull. As such the level and strength of construction hardly approaches that utilized for a capital ship. Keep in mind that both of these designs are essentially extentions of the Brooklyn class CLs. The weight savings realized with the switch from 5 triple 6" turrets to 3 triple 8" turrets was primarily applied towards protection but the hull structure retained the same strength (same frames, scantlings, etc.) of the Brooklyns. The Brooklyns, Wichita, Baltimores, and Clevelands all suffered in varying degrees from the structural weakness that plagued many of the treaty restricted designs (which is just about all the CAs and CLs that served in WWII). It wasn't until designers were freed of the treaty requirements that truly balanced and sound designs were realized, such as the Des Moines class (with a considerable increase in displacement). (Source: U.S. Cruisers, Norman Friedman)Additionally, if the Wichita and Baltimore are rerated as BD-B*, then their hull boxes would need to be recalculated as the basis for the hull boxes for each category are not linear.

[Jim O'Neil]

I noted the hull boxes being non-linear, but will have to wait to get an explanation on how they are computed.I am unsure of how we are confused... the WICHITA was the 'last' of the treaty limited CAs... Even then her full load displacement had grown to 13,700 tons by 1943. The design was given some room to grow...The BALTIMOREs were never Treaty Cruisers... their 13,600 ton 'standard' weight immediately says this... they served for many years after WW2 and I have never heard of them being described as weakly constructed. In fact, even the BROOKLYNs were very well built by cruiser standards. The BALTIMORES had some 200 tons of structural reinforcement over the basic BROOKLYN type design. 6.4 inch Class A armored belts and 7 inch barbettes (WICHITA) is well past heavy Cruiser standards...even ZARA couldn't compare. The 2.25 inch decks seem just under your armor limits, but the design was quite advanced and offered a good immunity zone versus any other cruiser. The BALTIMOREs have 6.7 inch belts and 2.5 inch decks ... The CLEVELANDS were definitely overloaded, and most were significantly weight reduced after the war... few stayed on after about 1955. Note that it was the BROOKLYNs, not the CLEVELANDs that were provided to other nations Navies.

[Jim O'Neil]

To add to my last post... the difference between BC and BD is not very clear... the armor values overlap and the speed differential is odd in an armor description... but I believe is attempting to refer to construction (I must assume) being somewhat lighter... HMS DREADNOUGHT was not as well sub-divided as later "super' Dreadnoughts, so we can assume a lesser level of underwater protection with BD, vice BC... I am not sure, but that is the only thing that makes sense... given that, some very heavily armored Heavy Cruisers probably deserve the BD designation.They don't have the same level of underwater protection as a battleship of WW2, but I suspect they compar well with DREADNOUGHT and her ilk.

[DAVID THORNLEY]

Coastal wrote:

The desgnator (BC, BA, CA, etc) is a rating of the ships resistance to damage and takes into account the armor level, construction and size of the ship. In the case you mention, the San Francisco would still be able to penetrate and cause full damage, including those you mentioned (and more, including a magazine explosion). Since the hull boxes are not linear (a BB hull box does not represent the same thing as a CA or DD hull box), a mechanism is needed to bring the hits inflicted by a 8" gun into the same plane as, say the hits inflicted by a 16" gun (or 5" gun). And this is what's happening in the Equivalent Hits table.

Except that, in GQIII, San Francisco appears to be unable to cause the historical damage.The US 8" gun has a maximum penetration of BD, and Hiei is BC. This means that it is not possible to inflict serious structural damage on the target with one hit, since all the good results are protected by armor.This was not a problem with GQI/II, in which the 8" gun had a very short range band at which it could penetrate BC armor.

[Jim O'Neil]

Point taken... and the US 8" could penetarte 10 inches of plate at low obliquity and short range...But the charts are not adjusted for national characteristics, excepting those for spotting.... all guns of the same caliber seem to be identical.

[Cpt M]

Based on the tables as printed (and a reading of the rules), the San Francisco's 8" battery will not cause full hull damage (point for point) but will cause a 1/2 point for each hit (non-penetrating Hull hits score 1/2 points). Additionally, it can cause Critical Hits, one of which is a Rudder failure (which does not require penetration); which nicely replicates the damage Hiei suffered. (BTW, Rudder damage can only be caused by Critical Hit; something unchanged from GQ1/2.) Given enough hits, its entirely possible for an 8" CA to sink a Kongo class.

[Jim O'Neil]

Respectfully disagree... HIEI took a couple of penetrations into her engine compartments and was able to muster only some 14 knots after a bit ... and that fell off to about 8 knots later IIRC.

[Cpt M]

Yes, and with the lost of sufficient hull points (which can be inflicted by the SF), and the reduction in speed, Hiei will then limp its way out of battle at a very reduced speed. All the points you raised are covered in the damage model as written. Just as you described.

[Cpt M]

The loss of 1/2 hull points in its own right is not insignificant and, given the accumulation of such hits, would model the results you noted.

[DAVID THORNLEY]

Except that this wasn't an accumulation of hits. It was two 8" shell hits. GQ1/2 models that well, by giving an 8" gun a very small rangeband to penetrate BC armor. GQ3 doesn't.In fact, Hiei was vulnerable to penetrating hits from USN 8" guns when very close, but not nearly as vulnerable farther out. In the game, there is no such differentiation.Nor have I seen any reason for why the charts were published as they are. They don't agree with the historical fact that a USN 8" gun could punch through Hiei's armor at very close range, and I don't see that the game results are in good agreement with the historical.Specifically, I have seen no reason why the bottom penetration of the USN 8" gun is BD rather than BC.If there was some good reason why the chart was made this way in the first place, I'd like to know of it. "It's not as bad as you thought it was" isn't a good reason.

[Jim O'Neil]

Thornley makes some good points... I thought, that perhaps it's the Armor rating of the KONGO's that is what is wrong. They had WW1 armor which was not altered on the belt, although the deck armor was increased significantly, boilers altered, AA guns improved and lots of internal adjusting. But this does not seem wholly true. They did not have great underwater protection by WW2 standards, despite the upgrades, as KONGO was lost to one submarine torpedo and the others seem to have had some problems controlling flooding. The problem seems to be with the penetration tables. The US 8 Inch gun could pentrate BC armor, see below. BD is 6-8 inches and BC is 7-9The KONGO's have 9 to 5 inch belts and 9 inch turret fronts.The US 8" gun is capable of penetratiing 10" of armor at 10,800 yards; the older 8" in the early cruisers (Pre-CA -37) would penetarte the same amount at 9,000 yards.From: http://www.navweaps....-55_mk12-15.htm

[Jim O'Neil]

Another excellent site with very good Armor penetration values is:http://www.geocities.com/kop_mic/I know some people are a bit reluctant to take computer generated numbers, but in this case, I think them quite accurate. Nathan Okun is a Terminal Effects Engineer for the Navy. He has access to a large library of data and has tailored 'Facehard' (his program) to reproduce known behavoir at known ranges and inclination. The interpalations between known data are very consistant with expected results. He is an exacting perfectionist, and the program is updated a couple times a year with improved formula's to provide what many of us would find insignificant detail improvements.The program itself is available off of the Combined Fleet site Jon Parshall runs.

[Lonnie Gill]

I've responded to the issue of being able to damage BA - BC targets with smaller batteries in the "What's the use of secondary batteries" discussion. The armor penetration issue being discussed here is a bit thornier. First, I've read a number of accounts of the San Francisco vs Hiei which are inconclusive as to whether the US 8" shells actually penetrated the Japanese main armor. Several of the Forum replies suggest that conclusive evidence is available. I'd look forward to reading the sources and settling this long standing question.Second, I took a conservative position on armor penetration. I consulted all the sources I could find when preparing the CRTs, including Mr. Okun's stellar work. Certainly, his work in this field is far, far beyond my limited understanding. His data does suggest the US 8" could penetrate; other data is contradictory. As the Historian for the US Tank Destroyer Association, I had occasion to research the sources for WW II tank armor penetration extensively. I found a set of published US Ordnance Department tables and graphs based on tests and penetration formula extrapolations which indicated that US 3" gun could penetrate the German Panther at 1200 - 1500 yards. Empirical tests performed in France in July 1944 clearly showed that to be far, far too optimistic. The point of all this is that I have since taken the position that when the information is not conclusive, it's better to be conservative. Further, I used a 30° from perpendicular model for the penetration data on the CRTs to account for the many factors which affect the actual angle of impact for a hit.Thus, I stopped with BD penetration for the 8" gun. The BD armor classification was developed primarily for the WW I era to reflect the early dreadnoughts. This classification (6" - 8") does indeed overlap the BC classification (7" - 9"), so there's room for further consideration on this point. Got conclusive data? Share it and we'll be able to reach a consensus on this. One of the prime tenets of General Quarters is a good basic system that you can evolve to incorporate your own ideas and new data as it becomes available.Meanwhile, you can accept my conservative position, or consider the 8" able to penetrate BC armor as well at minimum range - less that 6000 yards.

[Steven Gilchrist]

Using the GQ3, WW2 rules, it IS possible for the 8"guns of the US CAs involved in the First Guadalcanal naval brawl, to penetrate the armorer of the Japanese BCs. If you use the optional rule letting weapons penetrate one class higher when "crossing the T", then the USA 8" Guns can penetrate BC Armor hull at close range. Perhaps this really did happen and is when the IJN Hiei took some hull damage. It solves the problem of 8" guns being able to damage BCs. Of course, the part of the battle closing-in on a BC with 14" Guns will be very ... exciting (!) :laugh:

[Jim O'Neil]

I believe in the actual battle, the SAN FRANCISCO sailed broadside to HIEI at something less than 3000 yards and fired into her side. There is no question that the US 8" will penetrate at that range, and by a comfortable margin. The problems arise when angle of fall and angle off the broadside increase, as this alters the angle of strike and armor resistance starts to go up ever more rapidly after about 25º off of a perpendicular hit.GQ 3 has to include many variables with an assumed value, as computing it all for each shot or salvo would make it a mathematics game.Jim

[Cpt M]

^{A late update to this topic: With Amendment 1 the CRTs were changed to include a 3000 yds range band (the lowest range band on the original CRTs was 6000 yds) which allows 8" guns to penetrate BC armor.}