Subject: SMML VOL 2996 Date: Fri, 18 Nov 2005 22:10:09 +1100 The Ship Modelling Mailing List (SMML) is proudly sponsored by SANDLE http//sandlehobbies.com For infomation on how to Post to SMML and Unsubscribe from SMML http//smmlonline.com/aboutsmml/rules.html ---------------------------------------------------------------------------- MODELLERS INDEX 1 Japanese warships 2 just checking in 3 Re Yorktown and Force Z AAA Armament 4 Re Reply, thrust & counter thrust - This is informative fun 5 effectiveness of US WW2 AA weapons system 5" gun ---------------------------------------------------------------------------- MODELLERS ---------------------------------------------------------------------------- 1) From CokerRE@aol.com Subject Japanese warships For those who are interested in Japanese warships I highly recommend this site of detailed animations http//w2322.nsk.ne.jp/qm.masaki/index.html PC Coker ---------------------------------------------------------------------------- 2) From Donsrcships@wmconnect.com Subject just checking in Just wanted to take a moment to hi to all of you and hope everybody will have a grate weaken next week and don't eat to much.;-) OK what I have done I have taken a Lindbergh DD and change it over to a sumner class. DD 724, Had some scratch building but I was able to use a lot of the small parts from the kit. It will be RC when I am ready to set it up. DON ---------------------------------------------------------------------------- 3) From "Mark Shannon" Subject Re Yorktown and Force Z AAA Armament The point that a lot of the discussion is hinting at, but not making, is the inadequacy of hitting power in the close-in AAA armament in the sips discussed. Once the attacking aircraft have penetrated the distance that a barrage defense was effective at, the close in weapons of all of the navies in 1940-42 were not heavy enough to do what was needed, except for the 2-lber shell of the pom-pom and the single 40 mm Bofors mounted among the ships discussed. Experience through WWII showed that the 37mm-47mm range was the optimum for one-hit disruptive damage, with the existing state of loading and directing gear of the time. The early WWII close in defense of 0.50 caliber machine guns, without explosive rounds, or 20-25 mm cannon with light explosive rounds, was capable of shooting down the attacking aircraft, but typically not until torpedoes or bombs had been released. These lighter weapons required precise hits that killed or incapacitated essential aircrew, set off the plane's load in a 'miracle hit', or did immediate damage to the engine. Such hits only grew in probability as the range shrank, and the Japanese (and the Italians, who taught the Germans) released torpedoes outside of that range (1600 yards). These also could not reach high enough to damage the dive bombers in their vulnerable, stabilized attack mode. At the time of the Prince of Wales and Repulse sinking, and at Midway, the 40 mm Bofors type armament was just beginning to be seen in any numbers. The single mount on the PoW's fantail was considered a great improvement over anything else available. What the record show is that the German 37 mm single and quad mounts, and the Bofors in its variety of installations, could knock the attacker off its line -- even if it was a Lancaster bomber, as at the Moehne Dam. Even if the hit was not fatal to the attacking aircraft, the disruption of the attack, and the amount of damage a single hit could do, made the attack less accurate and may have required a plane to eventually jettison its load to survive. Later, when the Kamikaze attacks did come, the 20 mm was nicknamed 'the doorknocker,' because their firing just let the crew in down below action stations know the attackers were coming in. It was the 40 mm that was needed to knock the planes out of the sky, rather than do eventually fatal damage to them. The British had the right idea with the 2-lber pom-pom shell (40 mm), but the weapon was not designed for the longer ranges. A well-working octuple pom-pom could make even a staffel of Ju-87 Stukas think twice about pressing home an attack. But, it could not reach out to where the torpedoes were being dropped, certainly not by the Japanese bombers. It also could not reach the altitude of the level bombers. Until the later, predicting radar control came into its own, in later 1943, the heavy AA of 4.1-5.5" size range could not follow targets and reloaded too slowly for the direct-fire hosing needed to take on low-level attacks close in. The number of 20 mm mounts on the two ships was relatively low, by the standards of what was seen later to be needed, the 2-lber was facing an attack that it was not designed for, and the one 40 mm Bofors on the PoW was the only effective weapon for the type of attack delivered. Without fighter air cover, which needed to be there when the first Japanese planes were spotted and stay until the last Japanese sortie of the day, the Prince of Wales and the Repulse were doomed from the size of the attack by the type of armament they had -- even if the PoW had not suffered a devastating loss of power from shock damage of the first torpedo hit(s). As it was, the Japanese attack was not as accurate as legend puts it. Certainly not as accurate as Nagumo's carriers showed they were capable of. The two battleships received something like 10-12 torpedo hits in total, split as a maximum of five on Repulse and seven on Prince of Wales, according to my references, and of those, two or three of Repulse's hits, and 4 of the Prince of Wales's were delivered to sitting targets that were no longer able to defend themselves. This out of something near 45-50 attacking torpedo bombers. The level bombers were even less accurate, as might have been expected from this type of attack in all cases during the war. It was good, but not exemplary showing, though more than adequate in achieving its goal. Mark Shannon ---------------------------------------------------------------------------- 4) From "GRAHAM BOAK" Subject Re Reply, thrust & counter thrust - This is informative fun >> To Graham Boak, Sir you are correct about the aircover, incorrect, as there was none available, and what there was was thinly stretched, and inadequate. << What was in Malaya/Singapore was indeed inadequate by definition of the results obtained, though not really thinly stretched as much as tied to operating from few bases with poor integration. However, in the specific case of Force Z, there were Buffalo fighters based well within range that could have been covering the warships had the Naval Command bothered to keep the RAF informed. Even a few fighters on CAP would have broken up the initial attacks, and earlier warning would have resulted in other fighters arriving sooner, rather than immediately after the ships had sunk (as they did). Although I do not count myself among the Buffalo's admirers, it would have been sufficient to the need. Whether this would have significantly changed the overall shape of the campaign is, of course, quite another matter. It would, however, have reduced the number of blows to the morale of the defending forces. ---------------------------------------------------------------------------- 5) From "Reid, John (AFIT)" Subject effectiveness of US WW2 AA weapons system 5" gun I refuse to use AAA for WW2-era....show me an AAM prior to Project Bumblebee. Why was the US 5”/38 great? Was it the gun as such? Nope, ballistically far outperformed (as a gun) by many other contemporary pieces. But the characteristic smoke-ring after discharge is very pretty. Was it the mounting? For the twin, maybe – it had excellent rate-of-change of train and elevation, unlike (say) UK 5.25” which could neither train nor elevate fast enough to cope with contemporary aircraft (other than perhaps the FAA’s own, but that’s another recently beaten thread). Same appears to apply to Japanese 5” twin turrets e.g. on destroyers, hence continued use of 5”/40 open mount, better for AA. For the US 5” single gunhouses, also maybe – but the open central-pivot type mounts were nothing special. Was it the control system? For my money, yes – Mk37 clearly superior to anything else afloat in its ability to predict where to put the shell in 3D. Even so close, but by itself not close enough. (see Friedman on mid-war thoughts to replace 5” secondaries on BBs with 40mm). More reliable than most comparable systems too, due to better production engineering a director that is down for repairs does not help you much. See HMS Delhi and RN Battle (1943) Class for vote of confidence.... Was it the proximity-fused shell? Definitely increasing the kill-probability radius from 5” to about 10 feet, of course this drastically changes the SSPK. By 1944, there was at last a really effective long-range killer, not merely a deterrent. Good timing to make it work. Was it the training? Look at a Fletcher or the like, between the funnels apart from the torpedo tubes the funny-looking gadget is a 5” loader practice machine. How many other navies had anything similar so that the really important part of the weapons system, the part in blue uniforms, could be really battle ready before battle? Was it the sheer quantity (and logistic ease of having one gun to cover jobs performed in the RN by 4 different ones)? Certainly didn’t hurt. Being able to build enough simple small radars to be blown up as fuses was an industrial masterpiece. Was it any of these factors alone? No – the whole of the weapons system was much greater than the sum of the parts. John Reid Rome ---------------------------------------------------------------------------- Check out the SMML site for the List Rules, Reviews, Articles, Backissues, Member's models & Reference Pictures at http//smmlonline.com ---------------------------------------------------------------------------- End of Volume