B5N2 Kate production?
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findmeifyoucan
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RE: B5N2 Kate production?
More questions on this subject. What is actually happening when you press the upgrade tab and the expansion tab? What are you upgrading and what are you expanding to with regard to production for the Japanese and how expensive is it to do this?
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treespider
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RE: B5N2 Kate production?
Page 235
Here's a link to:
Treespider's Grand Campaign of DBB
"It is not the critic who counts, .... The credit belongs to the man who is actually in the arena..." T. Roosevelt, Paris, 1910
Treespider's Grand Campaign of DBB
"It is not the critic who counts, .... The credit belongs to the man who is actually in the arena..." T. Roosevelt, Paris, 1910
RE: B5N2 Kate production?
ORIGINAL: Chickenboy
Understood and agreed about the inferiority of USN air-dropped torpedoes, particularly in early-mid war.ORIGINAL: Puhis
ORIGINAL: Chickenboy
I can't imagine that, even if they were capable of 400mph at emergency war power, that Jills would have ever operated in such a manner. In that sense, there's just a lot of superfluous engine power and potential speed in the attack phase that is meaningless IRL.
Japanese type 91 torpedo was much better than US airborne torpedo. Later type 91 models were strengthened so that max drop speed was 350 kts (about 400 mph).
http://www.combinedfleet.com/torps.htm
When was this 'later' type 91 in widespread distribution and service? Was it in widespread service prior to the Battle of the Phillipine Sea? If not, what were its predecessor's engagement envelope parameters?
ETA: looked it up on the site. Most interesting. I wonder if these maximum speeds for drop were realistically determined on combat drops. As PP have indicated, a very large number of torpedoes failed to track or otherwise engage targets at their 'rated' attack speed. This suggests that these torpedoes, when combined with the delivery system (Jills) at high speeds were not WAD. Why?
Could it be that the IJN Bureau of Ordinance equivalent may have been exaggerating their parameters for engagement? Could metallurgic or other flaws have worked their way into the production system to offset theoretical structural gains with the later modifications?
I wonder if the IJN Bureau of Ordinance asked itself the same soul-searching questions that the USN did (albeit VERY late)? Would such questioning of authority and 'the system' been tolerated within the heirarchy of the mid-late war IJN?
Obviosly maximum drop speed was not optimal drop speed. I've read somewhere very high speed drops decreased hitting odds, so usually slower drop speed was used.
I think kate pilots used speed of about 200 kts (230 mph) when they hit Yorktown during battle of Midway. At that time the maximum drop speed of type 91 torpedo was 260 kts.
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Braedonnal
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RE: B5N2 Kate production?
ORIGINAL: Puhis
Japanese type 91 torpedo was much better than US airborne torpedo. Later type 91 models were strengthened so that max drop speed was 350 kts (about 400 mph).
http://www.combinedfleet.com/torps.htm
Late war the US Mark 13 was capable of drops from 2400 ft at 410kts so I wouldn't say Japanese airborne torpedoes were much better at that point. Early war, there was no contest with the Mark 13 being limited to 110kts at 50ft!
If a country can't save itself through the volunteer service of its own free people, then I say: Let the damned thing go down the drain!
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Chickenboy
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RE: B5N2 Kate production?
I must say that I was rather unaware that IJN and USN torpedoes were designed (later war) with such altitude and speed allowances. Learn something new every day....that's why this forum rocks. [&o]
RE: B5N2 Kate production?
[font=calibri]Hi there, you wanted to know the source of my information for the Nakajima B6N2 ‘Jill’. Well, first of all I must explain that I’ve never actually seen this aircraft ‘in the flesh’, unlike several from the WWII Pacific theatre where I’ve actually had the chance to evaluate from the cockpit (and also logged several hours in a Val & also an Avenger + a couple in a Corsair). [/font]
[font=calibri]My main source of information concerning performance & deployment must be David Brown’s ‘Carrier Fighters 1939-1945’, published by MacDonald & Jane’s of London (my edition is dated 1975). It is part of the MacDonald Illustrated War Studies, and the name is a bit of a misnomener as it goes into quite great detail concerning the technical specifications and performance of the ‘opposition’ (including Axis as well as Allies) to Allied carrier fighters, as well as in-depth examinations of all the aircraft involved, their armament, aircrew training and preparation, defensive & offensive tactics, development & doctrine etc. He has this to say about the B6N2 Jill :[/font]
[font=calibri]‘The B6N2 Jill was unquestionably the most lethal aircraft in the Japanese carriers’ 1944 air groups but although many broke through the Task Force 58 CAP on 19th June 1944, the aircrew were insufficiently trained to take full advantage of their attacking opportunities’.[/i][/font]
[font=calibri]At the Marianas Turkey Shoot he notes that it was being used by Car Div One (Zuikaku, Shokaku and Taiho) but there were still some B5N Kate’s present as not all the aircrews had been able to work up on the newer unforgiving[/i] (his italics) plane, they were part of Air Group 601. In Car Div Three only Zuiho was able to operate the heavy Jill, so Chitose and Chiyoda (now converted to CVL’s) were still stuck with the older obsolete Kate. It also seems that at least one carrier in Car Div Two operated the Jill during the battle. He also writes that the Jill was capable of 327 mph in level flight fully laden (although he doesn’t say at what altitude this was supposed to take place, however see below)[/font]
[font=calibri]For the battle itself, he gives some account of the Jill’s performance & tactics. In the first Japanese carrier strike, (c.64 aircraft, which appears to have come from Car Div Three), the main formation began to orbit at around 75 miles for a final pep-talk (and to give the Hellcat’s time to vector out to them) whilst the seven Jill’s present immediately broke away from the main group (at c.18,000 feet) and began their long, fast diving attack towards the US carrier core. The Jill’s were intercepted at 45 miles by the Hellcats who were unable to catch them despite doing around 350 mph, which shows that the Jill’s were already in excess of this speed. In the end only one Jill was shot down before the Hellcats were left far behind. However the remaining six had mis-identified their targets and were heading at top speed for TG 58.7, namely the AA-screening battleships, 20 miles away from the carrier groups.[/font]
[font=calibri]The last-ditch low level CAP (VF10 from Enterprise) got at least one Jill + a A6M2 fighter-bomber just before the AA barrage, but it was reported that about twenty EA’s made attacks, including the five remaining Jill’s. However although all the Jill’s dropped fish, none of them were seen to run true (which was probably due to the fact that they were flying far above safe dropping speed) and AA subsequently shot down two more, the remaining three Jill’s apparently escaping. [/font]
[font=calibri]The second Japanese strike was almost certainly Car Div One’s, and comprised of about 111 aircraft that again performed a final ‘pep talk’ orbit at around 90 miles to which the US eavesdropped & vectored out their CAP early. In the end the second strike was intercepted at between fifty five and thirty miles to the carriers and decimated by the Hellcats. Because the Japanese strike split into two main streams, one of which divided again, accounts are more confused than dealing with the first strike but it seems that all the Japanese bodies of aircraft were intercepted by the Hellcats and torn to shreds. However at least twenty Japanese aircraft managed to get through both the Hellcat umbrella and also the AA barrage, and Brown notes that a few Jill’s had again out-dived and thrown off the Hellcats as these came in first, very low and very fast. Far too fast it seems, as one was unable to pull out in time and crashed into Indiana’s armoured belt (there is some discussion as to whether this was an early suicide attack, but on the balance of evidence it seems as though this was an inexperienced pilot going far too fast and simply flew into what he was trying to torpedo). From reports it again seems as though although several fast-flying wave-skimming Jill’s were spotted dropping torpedo’s, none ran true. Enterprise and Princeton were both near-missed by torpedo’s, but spotters are adamant that these were dropped from the more slow-flying Kates.[/font]
[font=calibri]Finally there was another strike involving Jill’s later on, possibly from Car Div Two (c.47 planes, including at least seven Jill’s) flew to an erroneous position, then turned to look for TF58 & were detected by Hornet’s radar at ninety nine miles and then Yorktown & Hornet’s CAP made the interceptions at around forty miles, again shooting down a few fighter-bombers but were once more unable to catch the faster-flying Jill’s in their shallow dives. Several Jill’s were spotted attacking TG 58.4 but again with no success, probably because they were going far too fast, although Brown notes that at least one Jill, travelling far too quickly to attack or even pull up in time, hit the water barely 30 yards from the Essex.[/font]
[font=calibri] [/font]
[font=calibri]My second source for the Jill’s performance comes from the flight tests of captured Japanese aircraft by pilots of the Technical Air Intelligence Centre in Anacostia, between 1946-48, which were subsequently published (I think the editor or senior evaluator may have been a chap called Sickart or Siggart, can’t remember which & it doesn’t say on my (incomplete now) copy.[/font]
[font=calibri]Nakajima claimed that the B6N2 could do 297 mph fully-loaded at sea-level and 327 mph again fully loaded in level flight at 15,100 feet, whilst the Anacostia pilots claimed that they could only get it to do 299 mph fully loaded and in level flight at 16,100 feet. However, in an appendix (which could have been down to this chap Sickart) and foot-notes, it is reported that the US pilots tried to re-produce what the Japanese pilots did in their shallow dive-attacks against a couple of Hellcats and Corsairs – because of the Jill’s great weight whilst fully loaded, it could leave the Hellcats behind with ease (not so the Corsairs, they could just about keep up) and it was possible to reproduce the dive speeds approaching 400 mph as reported by US observers and spotters during the carrier battles of June ’44. (my italics). However, it is also somewhat cynically noted that the chances of a successful torpedo attack at these speeds were virtually nil, notwithstanding the high possibility of (given the Jill’s heavy weight) even being able to pull out in time – as observed in the Marianas battle (and reported by Brown, who doubtless was drawing on contemporary sources and observations from US servicemen who took part in the battle), several Jill’s no doubt piloted by semi-trained pilots were genuinely unable to level out. Proof of both the poor standard of training and also the tactics used by IJN – IMO the Japanese had a genuinely very good plane there, but never used it properly or had decent pilots to fly it.[/font]
[font=calibri]I don't know what torpedo the Jill (& Kate) pilots were using, I have heard of the type 91 & it was consistently far better than the US equivalent. However I can only re-state what I read above, basically saying that hardly any of the Jill-dropped fish ran true. Kate ones seem to have done, but then they were dropped at a slower & safer speed[/font]
[font=calibri]My main source of information concerning performance & deployment must be David Brown’s ‘Carrier Fighters 1939-1945’, published by MacDonald & Jane’s of London (my edition is dated 1975). It is part of the MacDonald Illustrated War Studies, and the name is a bit of a misnomener as it goes into quite great detail concerning the technical specifications and performance of the ‘opposition’ (including Axis as well as Allies) to Allied carrier fighters, as well as in-depth examinations of all the aircraft involved, their armament, aircrew training and preparation, defensive & offensive tactics, development & doctrine etc. He has this to say about the B6N2 Jill :[/font]
[font=calibri]‘The B6N2 Jill was unquestionably the most lethal aircraft in the Japanese carriers’ 1944 air groups but although many broke through the Task Force 58 CAP on 19th June 1944, the aircrew were insufficiently trained to take full advantage of their attacking opportunities’.[/i][/font]
[font=calibri]At the Marianas Turkey Shoot he notes that it was being used by Car Div One (Zuikaku, Shokaku and Taiho) but there were still some B5N Kate’s present as not all the aircrews had been able to work up on the newer unforgiving[/i] (his italics) plane, they were part of Air Group 601. In Car Div Three only Zuiho was able to operate the heavy Jill, so Chitose and Chiyoda (now converted to CVL’s) were still stuck with the older obsolete Kate. It also seems that at least one carrier in Car Div Two operated the Jill during the battle. He also writes that the Jill was capable of 327 mph in level flight fully laden (although he doesn’t say at what altitude this was supposed to take place, however see below)[/font]
[font=calibri]For the battle itself, he gives some account of the Jill’s performance & tactics. In the first Japanese carrier strike, (c.64 aircraft, which appears to have come from Car Div Three), the main formation began to orbit at around 75 miles for a final pep-talk (and to give the Hellcat’s time to vector out to them) whilst the seven Jill’s present immediately broke away from the main group (at c.18,000 feet) and began their long, fast diving attack towards the US carrier core. The Jill’s were intercepted at 45 miles by the Hellcats who were unable to catch them despite doing around 350 mph, which shows that the Jill’s were already in excess of this speed. In the end only one Jill was shot down before the Hellcats were left far behind. However the remaining six had mis-identified their targets and were heading at top speed for TG 58.7, namely the AA-screening battleships, 20 miles away from the carrier groups.[/font]
[font=calibri]The last-ditch low level CAP (VF10 from Enterprise) got at least one Jill + a A6M2 fighter-bomber just before the AA barrage, but it was reported that about twenty EA’s made attacks, including the five remaining Jill’s. However although all the Jill’s dropped fish, none of them were seen to run true (which was probably due to the fact that they were flying far above safe dropping speed) and AA subsequently shot down two more, the remaining three Jill’s apparently escaping. [/font]
[font=calibri]The second Japanese strike was almost certainly Car Div One’s, and comprised of about 111 aircraft that again performed a final ‘pep talk’ orbit at around 90 miles to which the US eavesdropped & vectored out their CAP early. In the end the second strike was intercepted at between fifty five and thirty miles to the carriers and decimated by the Hellcats. Because the Japanese strike split into two main streams, one of which divided again, accounts are more confused than dealing with the first strike but it seems that all the Japanese bodies of aircraft were intercepted by the Hellcats and torn to shreds. However at least twenty Japanese aircraft managed to get through both the Hellcat umbrella and also the AA barrage, and Brown notes that a few Jill’s had again out-dived and thrown off the Hellcats as these came in first, very low and very fast. Far too fast it seems, as one was unable to pull out in time and crashed into Indiana’s armoured belt (there is some discussion as to whether this was an early suicide attack, but on the balance of evidence it seems as though this was an inexperienced pilot going far too fast and simply flew into what he was trying to torpedo). From reports it again seems as though although several fast-flying wave-skimming Jill’s were spotted dropping torpedo’s, none ran true. Enterprise and Princeton were both near-missed by torpedo’s, but spotters are adamant that these were dropped from the more slow-flying Kates.[/font]
[font=calibri]Finally there was another strike involving Jill’s later on, possibly from Car Div Two (c.47 planes, including at least seven Jill’s) flew to an erroneous position, then turned to look for TF58 & were detected by Hornet’s radar at ninety nine miles and then Yorktown & Hornet’s CAP made the interceptions at around forty miles, again shooting down a few fighter-bombers but were once more unable to catch the faster-flying Jill’s in their shallow dives. Several Jill’s were spotted attacking TG 58.4 but again with no success, probably because they were going far too fast, although Brown notes that at least one Jill, travelling far too quickly to attack or even pull up in time, hit the water barely 30 yards from the Essex.[/font]
[font=calibri] [/font]
[font=calibri]My second source for the Jill’s performance comes from the flight tests of captured Japanese aircraft by pilots of the Technical Air Intelligence Centre in Anacostia, between 1946-48, which were subsequently published (I think the editor or senior evaluator may have been a chap called Sickart or Siggart, can’t remember which & it doesn’t say on my (incomplete now) copy.[/font]
[font=calibri]Nakajima claimed that the B6N2 could do 297 mph fully-loaded at sea-level and 327 mph again fully loaded in level flight at 15,100 feet, whilst the Anacostia pilots claimed that they could only get it to do 299 mph fully loaded and in level flight at 16,100 feet. However, in an appendix (which could have been down to this chap Sickart) and foot-notes, it is reported that the US pilots tried to re-produce what the Japanese pilots did in their shallow dive-attacks against a couple of Hellcats and Corsairs – because of the Jill’s great weight whilst fully loaded, it could leave the Hellcats behind with ease (not so the Corsairs, they could just about keep up) and it was possible to reproduce the dive speeds approaching 400 mph as reported by US observers and spotters during the carrier battles of June ’44. (my italics). However, it is also somewhat cynically noted that the chances of a successful torpedo attack at these speeds were virtually nil, notwithstanding the high possibility of (given the Jill’s heavy weight) even being able to pull out in time – as observed in the Marianas battle (and reported by Brown, who doubtless was drawing on contemporary sources and observations from US servicemen who took part in the battle), several Jill’s no doubt piloted by semi-trained pilots were genuinely unable to level out. Proof of both the poor standard of training and also the tactics used by IJN – IMO the Japanese had a genuinely very good plane there, but never used it properly or had decent pilots to fly it.[/font]
[font=calibri]I don't know what torpedo the Jill (& Kate) pilots were using, I have heard of the type 91 & it was consistently far better than the US equivalent. However I can only re-state what I read above, basically saying that hardly any of the Jill-dropped fish ran true. Kate ones seem to have done, but then they were dropped at a slower & safer speed[/font]
RE: B5N2 Kate production?
xj900uk---
Thank you so very much for sharing this information with us. I am sure that it gives all of us JFB's pause to think.
Caliban
Thank you so very much for sharing this information with us. I am sure that it gives all of us JFB's pause to think.
Caliban
RE: B5N2 Kate production?
Thank God for the invention of the proximity round [;)]
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Chickenboy
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RE: B5N2 Kate production?
xj900uk,
Thanks for sharing. Not exactly primary research you've provided, but interesting.
I particularly note the observation that he shares about travelling 'far above safe dropping speed' being the rationale for the torpedo failure. Yet the references from Combined Fleet that you've provided indicate that the 350mph-range drops should be within the operational envelope of the advanced IJN aerial torpedoes. Furthermore, why would the IJN naval aviators be engaging enemy ships at such ridiculously low levels? Combined Fleet's data indicates that these torpedoes can be dropped from about 2000 ft.!
Something's not adding up.
I'm not necessarily buying the conclusion of the writer that inexperienced crews were the source of the problem. Who says? Maybe the Jill was just too heavy to be operating at such speeds so close to the water. Maybe doctrine was insufficiently flexible to allow the Jills to slow down and engage at more realistic speeds (ala the Kates). Maybe the torpedoes weren't all they were cracked up to be and the advertised envelope for engagement (350mph and 2000ft drops) was hokum.
Anyways, thanks for digging this up.
Thanks for sharing. Not exactly primary research you've provided, but interesting.
I particularly note the observation that he shares about travelling 'far above safe dropping speed' being the rationale for the torpedo failure. Yet the references from Combined Fleet that you've provided indicate that the 350mph-range drops should be within the operational envelope of the advanced IJN aerial torpedoes. Furthermore, why would the IJN naval aviators be engaging enemy ships at such ridiculously low levels? Combined Fleet's data indicates that these torpedoes can be dropped from about 2000 ft.!
Something's not adding up.
I'm not necessarily buying the conclusion of the writer that inexperienced crews were the source of the problem. Who says? Maybe the Jill was just too heavy to be operating at such speeds so close to the water. Maybe doctrine was insufficiently flexible to allow the Jills to slow down and engage at more realistic speeds (ala the Kates). Maybe the torpedoes weren't all they were cracked up to be and the advertised envelope for engagement (350mph and 2000ft drops) was hokum.
Anyways, thanks for digging this up.
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Braedonnal
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RE: B5N2 Kate production?
It is possible that they were still using the older torpedoes too. It takes some time from research and development to testing to mass production and shipping them out to the fleet.
In 'Kaigan: strategy, tactics and technology in the Imperial Japanese Navy' it shows attack altitudes of 10-160ft in their training and lists that the Type 91 could be dropped at 100m but the next 12 pages I couldn't read online presumably with other torpedo model data (lousy free book preview). Looks like another book I need to buy.[:D] Best I could find at the moment.
In 'Kaigan: strategy, tactics and technology in the Imperial Japanese Navy' it shows attack altitudes of 10-160ft in their training and lists that the Type 91 could be dropped at 100m but the next 12 pages I couldn't read online presumably with other torpedo model data (lousy free book preview). Looks like another book I need to buy.[:D] Best I could find at the moment.
If a country can't save itself through the volunteer service of its own free people, then I say: Let the damned thing go down the drain!
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Mike Scholl
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RE: B5N2 Kate production?
ORIGINAL: Chickenboy
I particularly note the observation that he shares about travelling 'far above safe dropping speed' being the rationale for the torpedo failure. Yet the references from Combined Fleet that you've provided indicate that the 350mph-range drops should be within the operational envelope of the advanced IJN aerial torpedoes. Furthermore, why would the IJN naval aviators be engaging enemy ships at such ridiculously low levels? Combined Fleet's data indicates that these torpedoes can be dropped from about 2000 ft.!
Something's not adding up. Note that the claims were that it could be safely "dropped" at 350 mph from 2,000 feet. Basically claims that it wouldn't break-up on impact under those conditions..., but not that it could hit anything. Remember, Yamato was supposedly unsinkable, magnetic exploders were supposed to work, staunch fighting spirit was supposed to beat firepower..., lots of things that were supposed to happen didn't.
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Chickenboy
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RE: B5N2 Kate production?
Yeah, but Mike, we don't know what happened to those Jill torpedoes from the Phillipine Sea engagement. It wasn't as though forensic military BurOrd teams scavenged sunk warheads from the 20,000 foot depths. We don't know (or at least I haven't heard any evidence) supporting a torpedo misguide versus breakup.
The two terms may overlap. What happens when guidance fins get knocked off of the torpedo or bent upon contact with the water at high speeds? Is that a 'torpedo break up' or 'misguide'? Either one is an ineffective weapon system, regardless of the classification. It would be nice to know what really happened to those warshots, but not sure we ever will.
The two terms may overlap. What happens when guidance fins get knocked off of the torpedo or bent upon contact with the water at high speeds? Is that a 'torpedo break up' or 'misguide'? Either one is an ineffective weapon system, regardless of the classification. It would be nice to know what really happened to those warshots, but not sure we ever will.
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Mike Scholl
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RE: B5N2 Kate production?
ORIGINAL: Chickenboy
Yeah, but Mike, we don't know what happened to those Jill torpedoes from the Phillipine Sea engagement. It wasn't as though forensic military BurOrd teams scavenged sunk warheads from the 20,000 foot depths. We don't know (or at least I haven't heard any evidence) supporting a torpedo misguide versus breakup.
Well, we don't know why..., but we do know they didn't hit anything. Which at the least, fails to support the theory that they were effective when dropped at high speed from high (for torpedo A/C) altitudes...
RE: B5N2 Kate production?
ORIGINAL: Braedonnal
It is possible that they were still using the older torpedoes too. It takes some time from research and development to testing to mass production and shipping them out to the fleet.
In 'Kaigan: strategy, tactics and technology in the Imperial Japanese Navy' it shows attack altitudes of 10-160ft in their training and lists that the Type 91 could be dropped at 100m but the next 12 pages I couldn't read online presumably with other torpedo model data (lousy free book preview). Looks like another book I need to buy.[:D] Best I could find at the moment.
What page are you quoting from? I have a copy.
In late-1941, the Japanese Navy discovered they only had 10-30% of the airborne torpedo and 20mm ammunition stocks they needed to fight a war (following their doctrine!), so they immediately began expansion of their production capacity.
Harry Erwin
"For a number to make sense in the game, someone has to calibrate it and program code. There are too many significant numbers that behave non-linearly to expect that. It's just a game. Enjoy it." herwin@btinternet.com
"For a number to make sense in the game, someone has to calibrate it and program code. There are too many significant numbers that behave non-linearly to expect that. It's just a game. Enjoy it." herwin@btinternet.com
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Chickenboy
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RE: B5N2 Kate production?
Agreed.ORIGINAL: Mike Scholl
ORIGINAL: Chickenboy
Yeah, but Mike, we don't know what happened to those Jill torpedoes from the Phillipine Sea engagement. It wasn't as though forensic military BurOrd teams scavenged sunk warheads from the 20,000 foot depths. We don't know (or at least I haven't heard any evidence) supporting a torpedo misguide versus breakup.
Well, we don't know why..., but we do know they didn't hit anything. Which at the least, fails to support the theory that they were effective when dropped at high speed from high (for torpedo A/C) altitudes...
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Braedonnal
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RE: B5N2 Kate production?
ORIGINAL: herwin
What page are you quoting from? I have a copy.
In late-1941, the Japanese Navy discovered they only had 10-30% of the airborne torpedo and 20mm ammunition stocks they needed to fight a war (following their doctrine!), so they immediately began expansion of their production capacity.
Page 327 at the bottom, talks about in 1931 they developed the Type 91 which was capable (at that time) of 100kts at 100m. Presumably this was much improved by 1941. Page 344-345 talks about the tactics of aerial torpedo attack with diagrams showing attacks from 16-160ft.
If a country can't save itself through the volunteer service of its own free people, then I say: Let the damned thing go down the drain!
RE: B5N2 Kate production?
ORIGINAL: Braedonnal
ORIGINAL: herwin
What page are you quoting from? I have a copy.
In late-1941, the Japanese Navy discovered they only had 10-30% of the airborne torpedo and 20mm ammunition stocks they needed to fight a war (following their doctrine!), so they immediately began expansion of their production capacity.
Page 327 at the bottom, talks about in 1931 they developed the Type 91 which was capable (at that time) of 100kts at 100m. Presumably this was much improved by 1941. Page 344-345 talks about the tactics of aerial torpedo attack with diagrams showing attacks from 16-160ft.
1937: 120 knots/200 m.
1935: accuracy against moving targets of 70-80%
This was then lost during the operations in China and had to be regained by furious training during 1940-41. The Type 91 was modified during 1940-41 to support launches in shallow water.
Harry Erwin
"For a number to make sense in the game, someone has to calibrate it and program code. There are too many significant numbers that behave non-linearly to expect that. It's just a game. Enjoy it." herwin@btinternet.com
"For a number to make sense in the game, someone has to calibrate it and program code. There are too many significant numbers that behave non-linearly to expect that. It's just a game. Enjoy it." herwin@btinternet.com
RE: B5N2 Kate production?
The drop parameters of IJN aerial torpedoes are addressed in a website devoted to the attacks on Force Z. The important point made there is that although the IJN BuOrd said one could drop their torpedoes accurately flying at 3000 kts from outside the orbit of Jupiter the flyers in their Nells and Bettys found that the lower and the slower one went the greater the accuracy. Twenty meters altitude or so was found to be about the optimum.
Those units were charged with an extremely important mission (stopping Force Z from interfering with the Malaya Invasion) and trained intensively to carry out that mission with torpedoes prior to the outbreak of war. They had the luxury of carrying out their training in a "scientific manner". It's probably worth noting that that mission was carried out successfully and that in fact the attack on Force Z was in reality the only "good day" those bombers had during the entire war.
Those units were charged with an extremely important mission (stopping Force Z from interfering with the Malaya Invasion) and trained intensively to carry out that mission with torpedoes prior to the outbreak of war. They had the luxury of carrying out their training in a "scientific manner". It's probably worth noting that that mission was carried out successfully and that in fact the attack on Force Z was in reality the only "good day" those bombers had during the entire war.
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Mike Scholl
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RE: B5N2 Kate production?
ORIGINAL: spence
The drop parameters of IJN aerial torpedoes are addressed in a website devoted to the attacks on Force Z. The important point made there is that although the IJN BuOrd said one could drop their torpedoes accurately flying at 3000 kts from outside the orbit of Jupiter the flyers in their Nells and Bettys found that the lower and the slower one went the greater the accuracy. Twenty meters altitude or so was found to be about the optimum.
Those units were charged with an extremely important mission (stopping Force Z from interfering with the Malaya Invasion) and trained intensively to carry out that mission with torpedoes prior to the outbreak of war. They had the luxury of carrying out their training in a "scientific manner". It's probably worth noting that that mission was carried out successfully and that in fact the attack on Force Z was in reality the only "good day" those bombers had during the entire war.
AGREE ABSOLUTELY! Too many players look at "design specs" rather than "real world operation". [8|]
RE: B5N2 Kate production?
Thanks for the above feedback. Am also wondering re the general inexperience of the Japanese flight crews piloting the Jills - we do have fairly good evidence that several were going so fast they were simply unable to slow up in time and crashed into the water (or into the indiana). Also you have to consider the actual process of dropping the torpedo - it needs decent calm water, no waves/splashes etc. A novice pilot could be panicked into dropping the fish the moment he gets into range regardless of what the water is like beneath him and no bothering to check if it's 'dirty'
I can remember a few years back a talk by one of the Swordfish aircrew who went after the Bismark. It was fascinating, and also provided a valuable insight into the process of dropping a live 'fish'. So much so that myself and a few mates went and put one into a TBF Avenger and went and dropped one live into an old flooded quarry in Leicestershire, and following that success tried it in the open ocean off the Scily Isles - it went haywire and off course - proves that the ocean drops aren't as easy as you believe). Anyway, he said that approaching the Bismark, the seas were very rough and they were worried their fish wouldn't run true. So this bloke (think he was the navigator) was leaning out of the big cockpit with his head over the side, waiting for a calm patch/trough of water at which point he tapped his pilot on the head telling him to drop the fish, which is what happened. He then waited for it to break the surface with bubbles and to their delight and joy they got a 'runner' (BTW it hopelessly missed the Bismark)
I can remember a few years back a talk by one of the Swordfish aircrew who went after the Bismark. It was fascinating, and also provided a valuable insight into the process of dropping a live 'fish'. So much so that myself and a few mates went and put one into a TBF Avenger and went and dropped one live into an old flooded quarry in Leicestershire, and following that success tried it in the open ocean off the Scily Isles - it went haywire and off course - proves that the ocean drops aren't as easy as you believe). Anyway, he said that approaching the Bismark, the seas were very rough and they were worried their fish wouldn't run true. So this bloke (think he was the navigator) was leaning out of the big cockpit with his head over the side, waiting for a calm patch/trough of water at which point he tapped his pilot on the head telling him to drop the fish, which is what happened. He then waited for it to break the surface with bubbles and to their delight and joy they got a 'runner' (BTW it hopelessly missed the Bismark)