Japanese submarines and aircraft

[ChezDaJez]

I suspect those boats were loud.

Also, the crews on the nuclear boats probably would have glowed in the dark.

Quite right. I loved tracking those boats! Sonobuoy detection ranges were measured in miles not yards. They also had a very unique signature compared to other boats which made classifying them a piece of cake. A single glance at a lofargram and you could determine his operating mode immediately. Woe be it to the crew that lost contact of one of these guys! An yes, they were so loud I didn't often bother to listen to their sound patterns. It hurt too much!

Something on the order of 40-50% of Soviet crewmembers who served on these boats developed some form of radiation sickness while on patrol. Many had long-term effects including birth defects in their offspring, leukemias and multitudes of other cancers. More and more open source literature is becoming available on the effects from serving in these boats.

Chez

[herwin]

ORIGINAL: el cid again

ORIGINAL: m10bob

ORIGINAL: herwin

I suspect those boats were loud.

Also, the crews on the nuclear boats probably would have glowed in the dark.

And that early on, nobody knew the deadly effects of radiation poisoning. Note the use of American troops openly deployed in blast areas stateside!
Oft noted are the many stars who died from cancer after filming the John Wayne film in which he portrayed Ghenghis Khan?

Not just stars - everyone present.

I have my doubts. Of course, my mother did fallout analysis for the Manhattan Project.

[herwin]

ORIGINAL: el cid again

ORIGINAL: herwin

ORIGINAL: Dili

I think all open sea recon is overpowered - in other hand radio intelligence is underpowered. This has diverse resons one of them is the aircraft availability Vs frequency of operations, crew fatigue etc, then for float planes there is also the recover times (for CS and AVs) , sea state, and gasoline. Anyone knows how many missions a Glen could make from a submarine, and if they had an engine replacement?

The open sea recon is vastly overpowered. A VP squadron was not good for 360 degree coverage except at very short range. More like 100 degree coverage.

The SIGINT model is definitely underpowered, although I've found I can track the KB through Japanese rear areas with some reliability as long as I use the MST algorithm.

What is the MST algorithm?

A maneuvering ship tracking algorithm. It's unlike a Kalman filter in that it's non-linear. A guy at Caltech showed it could be chaotic.

[herwin]

ORIGINAL: ChezDaJez

I suspect those boats were loud.

Also, the crews on the nuclear boats probably would have glowed in the dark.

Quite right. I loved tracking those boats! Sonobuoy detection ranges were measured in miles not yards. They also had a very unique signature compared to other boats which made classifying them a piece of cake. A single glance at a lofargram and you could determine his operating mode immediately. Woe be it to the crew that lost contact of one of these guys! An yes, they were so loud I didn't often bother to listen to their sound patterns. It hurt too much!

Something on the order of 40-50% of Soviet crewmembers who served on these boats developed some form of radiation sickness while on patrol. Many had long-term effects including birth defects in their offspring, leukemias and multitudes of other cancers. More and more open source literature is becoming available on the effects from serving in these boats.

Chez

I doubt the Japanese would have been much better.

I worked on the AN/BSY-2 SCS, and later did systems engineering for the Virginia class boats.

[JWE]

ORIGINAL: herwin

ORIGINAL: ChezDaJez

I suspect those boats were loud.

Also, the crews on the nuclear boats probably would have glowed in the dark.

Quite right. I loved tracking those boats! Sonobuoy detection ranges were measured in miles not yards. They also had a very unique signature compared to other boats which made classifying them a piece of cake. A single glance at a lofargram and you could determine his operating mode immediately. Woe be it to the crew that lost contact of one of these guys! An yes, they were so loud I didn't often bother to listen to their sound patterns. It hurt too much!

Something on the order of 40-50% of Soviet crewmembers who served on these boats developed some form of radiation sickness while on patrol. Many had long-term effects including birth defects in their offspring, leukemias and multitudes of other cancers. More and more open source literature is becoming available on the effects from serving in these boats.

Chez

I doubt the Japanese would have been much better.

I worked on the AN/BSY-2 SCS, and later did systems engineering for the Virginia class boats.

I see you worked on the Virginia class boats; you must then know Bill Christie (William P. Christie, Capt. USN (Ret)). He is my friend and mentor. He lives just 7 miles down the road, in Mission Viejo. He and Jeannie are frequent dinner guests at Casa Juan, so if there is anything you want to say, I’ll be pleased to relay it.

I also note you worked on the AN/BSY-2 SCS. This is so fun!! Once upon a time, I worked for Harris, Corp., Melbourne, FL, and developed the driver array circuitry and software for the SPY-1 system. My Program Manager, Clyde Coombs, took the concept to V. Adm. Purcell and we went to Stanford and worked with Dr. Jack Pribram to turn it into the BQQ-05. Gerry Randolph (who doesn’t know Gerry if you are a prime) took the shell to Eaton and the rest, as they say ..

This is exciting, you knowing Bill and Gerry (Clyde and Chuck Purcell have both passed). I will be in Arlington next week on a related matter, and I will likely have a cold Irish with Gerry. I would be pleased to pass on anything you want to relay.

JWE

[el cid again]

ORIGINAL: Dili

Further, every algorithm explained (or otherwise figured out) tends to have multiple inputs. I bet you are wrong - weather is factored in directly or indirectly - by one - or both - of these mechanisms.

I was talking generaly not in game terms. How many planes needed to search at 10 hexes not factoring weather?

As for sustainability - dynamic situations are not entirely sustained - big search planes with long ranges have relief pilots - units often have up to 50% extra aircrew and on search missions they often do not fly all the planes at one time.

Well for the 100% to have any meaning it should mean an extraordinary not sustainable mission profiles.

A gigantic WWII task force - with hundreds of shps - should not be missable by anything - except possibly a submarine periscope search in adverse conditions. On the other hand, a minor patrol vessel - alone - or a submarine on the surface - should not be quite hard to detect. A submerged submarine even harder - but not impossible if you are directly overhead in some conditions. Everything else is in between. My impression the game is pretty good at this. Why do you think it treats everything as 100%?

[el cid again]

ORIGINAL: Nikademus

ORIGINAL: el cid again

Au contraire, mon ami, the US was too bigoted to believe in Japanese submarine technology in 1945/6.

I'm sure there was bias. I don't need Friedman to confirm that. I only need Blair's forward in Vol one of Hitler's Uboat war. I did say that elements of Japanese sub design were viewed with interest. The I-400 concept as a whole in WWII however was not practical and they would have been hideously vulneable to Allied ASW.

We came to believe in "strike from the sea" being submarine based after the Soviets obtained atomic weapons much sooner than the "decades at least" expectation set by Gen Groves. And the design concept more or less made it all the way to hardware - except the jets were replaced by winged pilotless cruise missiles.

If your referring vaguely to US submarine design postwar, it was not based on I-400.

Yes I am. Take a look at it (in US Submarines Since 1945). I do not think any honest observer aware of I-400 would miss the connection. Submarine with tubular hanger for three aircraft. What makes you think it isn't related?

[el cid again]

ORIGINAL: Terminus

Wonder how long the Sen Toku's took to submerge? The Surcouf took over 15 minutes...

Much better than you would expect. I don't remember exactly - but it was remarkable for such a boat.
Nevertheless, it was a dog by the standards of an attack boat, it would be a great sonar target (active or passive), and the charge it would be vulnerable to US ASW is a solid one. It was intended to evade detection - and could do that better than any other aircraft carrier. IT also could strike from great distances (compared to guns or torpedoes). In that sense it was viable as a concept. But unless care was taken in target selection and routing, it must fail.

[el cid again]

It may be some or other books or even teachers are saying submarine reactors use low enrichment levels of uranium - but in all cases - US - Soviet - British - French - Chinese - they use very highly enriched uranium - and always did. It may once have been a secret - I remember when even words like "electronic warfare" were classified Secret - but it isn't any more.

[el cid again]

ORIGINAL: ChezDaJez

I suspect those boats were loud.

Also, the crews on the nuclear boats probably would have glowed in the dark.

Quite right. I loved tracking those boats! Sonobuoy detection ranges were measured in miles not yards. They also had a very unique signature compared to other boats which made classifying them a piece of cake. A single glance at a lofargram and you could determine his operating mode immediately. Woe be it to the crew that lost contact of one of these guys! An yes, they were so loud I didn't often bother to listen to their sound patterns. It hurt too much!

Something on the order of 40-50% of Soviet crewmembers who served on these boats developed some form of radiation sickness while on patrol. Many had long-term effects including birth defects in their offspring, leukemias and multitudes of other cancers. More and more open source literature is becoming available on the effects from serving in these boats.

Chez

A visit to Soviet military retirement homes / hospitals is depressing when you visit these crew- many of whom are probably now dead. It was very tragic. Once or twice some of them died to prevent accidents from causing much worse disasters - involving us. This is not the only thing of its sort - the Soviets also had a horrible accident with a waste disposal site - and the area was not safe to linger in for decades. The entire maintenance crew was killed from radiation - although not before they piled 30 meters of dirt on top of the mess with bulldozers.

[el cid again]

ORIGINAL: herwin

ORIGINAL: el cid again

ORIGINAL: m10bob




And that early on, nobody knew the deadly effects of radiation poisoning. Note the use of American troops openly deployed in blast areas stateside!
Oft noted are the many stars who died from cancer after filming the John Wayne film in which he portrayed Ghenghis Khan?

Not just stars - everyone present.

I have my doubts. Of course, my mother did fallout analysis for the Manhattan Project.

There is an article in my files about a town that was "expendable" - a US town poisoned by fallout. And we had an indicen in the Pacific that messed up crew on a Japanese ship pretty bad - but the test was much bigger than planned.

[el cid again]

ORIGINAL: herwin

ORIGINAL: el cid again

ORIGINAL: herwin




The open sea recon is vastly overpowered. A VP squadron was not good for 360 degree coverage except at very short range. More like 100 degree coverage.

The SIGINT model is definitely underpowered, although I've found I can track the KB through Japanese rear areas with some reliability as long as I use the MST algorithm.

What is the MST algorithm?

A maneuvering ship tracking algorithm. It's unlike a Kalman filter in that it's non-linear. A guy at Caltech showed it could be chaotic.

So how can you track KB using it in the game?

[el cid again]

ORIGINAL: herwin

ORIGINAL: ChezDaJez

I suspect those boats were loud.

Also, the crews on the nuclear boats probably would have glowed in the dark.

Quite right. I loved tracking those boats! Sonobuoy detection ranges were measured in miles not yards. They also had a very unique signature compared to other boats which made classifying them a piece of cake. A single glance at a lofargram and you could determine his operating mode immediately. Woe be it to the crew that lost contact of one of these guys! An yes, they were so loud I didn't often bother to listen to their sound patterns. It hurt too much!

Something on the order of 40-50% of Soviet crewmembers who served on these boats developed some form of radiation sickness while on patrol. Many had long-term effects including birth defects in their offspring, leukemias and multitudes of other cancers. More and more open source literature is becoming available on the effects from serving in these boats.

Chez

I doubt the Japanese would have been much better.

I worked on the AN/BSY-2 SCS, and later did systems engineering for the Virginia class boats.

This is a fair guess. I got to look at four different Japanese SSN designs (One based on I-400, two based on C type, and one KD type hulls) - and the standards were significantly less than ours were (in the first generation). They took exactly the same time to build their first SSN as we did ours - and it was remarkably similar in many technical respects - except the reactor technology was very different. But their standards were quite a bit better than the HEN in terms of shielding. Still - I would not want to sail on one if I was young enough to worry about fertility.

[herwin]

ORIGINAL: el cid again

ORIGINAL: herwin

ORIGINAL: el cid again




What is the MST algorithm?

A maneuvering ship tracking algorithm. It's unlike a Kalman filter in that it's non-linear. A guy at Caltech showed it could be chaotic.

So how can you track KB using it in the game?

I apply it by hand to the SIGINT and Ops reports. Bohdi's utility is useful in this because you can display the tracks over a period of time. It's not obvious when you look at a single game turn, but those TF markers line up over time. The KB is loud and easy to spot--all you have to do is extrapolate over the gaps, taking account of likely/potential maneuvering. I have worked on a number of systems that did just that. I've thought about writing my own version of MST and doing this automatically.

The hard part of the problem is not track maintenance--you can use a Kalman particle filter for that--it's associating detections with active tracks. That's where the chaos comes in, and where enemy tactics can be a problem. For game purposes, you can probably take a Bayesian approach, eventually based on human expertise. I'm headed in that direction (slowly) in my research into how bats track moving objects.

[ChezDaJez]

It may be some or other books or even teachers are saying submarine reactors use low enrichment levels of uranium - but in all cases - US - Soviet - British - French - Chinese - they use very highly enriched uranium - and always did. It may once have been a secret - I remember when even words like "electronic warfare" were classified Secret - but it isn't any more.

I won't comment on what modern US submarine nuclear reactor fuel is enriched to. But you are wrong about the Russian subs. The Oscar class uses U-235 enriched to about 45%. That is the highest level of any Russian PWR submarine reactor. You may be confusing that with the liquid metal-cooled Alfa or some Russian icebreakers that use 40-45% enriched U-235 (Arktika class icebreakers) or the Sevmorput which uses 90% enriched U-235.

By comparison, nuclear power generation plants throughout the world typically use U-235 that has only been enriched to about 3-4% (at least the ones for "peaceful puposes"). And France reported in 2006 that they were dropping their enrichment levels for naval vessels to 6-7% enriched U-235.

Chez

[m10bob]

Regarding the radiation dangers of fallout early on:

http://www.straightdope.com/classics/a2_016.html

And this, just examples of the ignorance of the times..(It is easy to lay fault with all the evidence in, but at the time, it was not "in".):

http://www.netti.fi/~makako/mind/radiatio.htm

[m10bob]

An interesting read regarding the potential of the I-400's..:

http://www.militaryhistoryonline.com/ww ... ersub.aspx

[DuckofTindalos]

The author of that article suffers from the same infatuation with huge weapons that the Axis had during the war.

The planned attack on the Panama Canal was a PIPE DREAM; the Sen Toku's would have to spend three quarters of an hour on the surface of the water to launch their aircraft, in hostile waters, presumably in daylight (or at most, at dawn), in hostile waters, hoping and praying not to be spotted by enemy air patrols. You think their 10*25mm guns would have been ANY sort of meaningful defence against a concerted air attack? I can assure you, they wouldn't; the Germans tried making flak submarines without success, and they had flak guns that actually WORKED.

The Sen Tokus were white elephants, a dead-end technology. They were an illogical continuation of the midget submarine carriers of the earlier war, with the added "advantage" that their "midgets" (the Seirans) could be more easily intercepted and destroyed.

They were huge wastes of resources and militarily irrelevant. Too bad about the Seirans, though. They were pretty much the only worthwile thing to come out of the Sen Toku program; good aircraft.

[Nikademus]

ORIGINAL: el cid again

[Yes I am. Take a look at it (in US Submarines Since 1945). I do not think any honest observer aware of I-400 would miss the connection. Submarine with tubular hanger for three aircraft. What makes you think it isn't related?

The fact that post-war US subs did not use the same hull structure. I-400's size and ability to hanger several aircraft does not give her inspiration status for the future carrying of ballistic missiles. Rather, she was the end product of a long line of aircraft carrying subs that Japan felt was needed for her pre-war battlefleet.

[el cid again]

ORIGINAL: ChezDaJez

It may be some or other books or even teachers are saying submarine reactors use low enrichment levels of uranium - but in all cases - US - Soviet - British - French - Chinese - they use very highly enriched uranium - and always did. It may once have been a secret - I remember when even words like "electronic warfare" were classified Secret - but it isn't any more.

I won't comment on what modern US submarine nuclear reactor fuel is enriched to. But you are wrong about the Russian subs. The Oscar class uses U-235 enriched to about 45%. That is the highest level of any Russian PWR submarine reactor. You may be confusing that with the liquid metal-cooled Alfa or some Russian icebreakers that use 40-45% enriched U-235 (Arktika class icebreakers) or the Sevmorput which uses 90% enriched U-235.

By comparison, nuclear power generation plants throughout the world typically use U-235 that has only been enriched to about 3-4% (at least the ones for "peaceful puposes"). And France reported in 2006 that they were dropping their enrichment levels for naval vessels to 6-7% enriched U-235.

Chez

The problem is power density. Lower enrichment levels do not permit sufficient power density for a sufficiently compact installation - and submarines are not (usually) that big. The other method - tried by Japan and France - and possibly UK in a wartime study - was to use heavy water. This is more expensive than uranium fuel - and supply in quanitity is always a big issue. Only Japan (pre war) and Canada (post war) solved it on a large scale. This is a different way to get power density - and also lower pressures - but it is actually more expensive.