WI Japan Tried a Blockship at Pearl Harbor ?

robdab2

Banned
Hannibal. Ceasar,

Thanks for the "heads up".

... but I know that members have little to no patience when a thread becomes redundant and one side begins parroting back arguments to the other. - Yeah, I've read some of the endless early "debates" with bard32. I wasn't aware that I had done so and will try to guard against doing so in the future. I can only attempt to refute concerns, one by one, as they are posted by my readers.

After reading through the posts, I have to agree with the majority on here, that this TL is ASB. - This kind of a response is exactly what I find so frustrating here. By presenting no sourced and detailed points of dis-agreement with my scenario, you allow me no opportunity to research and present any kind of a counter-arguement. There is no way for debate, discussion or learning, thru the exchange of ideas, to proceed on between us.

Two short posts ago FlyingDutchman presented a sourced list of items wrt my scenario that he disagreed with. I was able to respond fairly quickly with a source and further explanation of my scenario, in an attempt to convince him of the feasibility of that proposal. Maybe I'll succeed, maybe I won't but at least FlyingDutchman and I can have a civilized discussion about my AH.

Other than this message, how can I possibly respond further to you on this topic since you've given me no explanation at all of your negative pov ?

Just an easy and fast to type "ASB" label.

Isn't the purpose of posting/reading at a place titled "Aternative History Discussion Board" to actually discuss alternative histories ?
 

robdab2

Banned
Hannibal. Ceasar,

Thanks for the "heads up".

... but I know that members have little to no patience when a thread becomes redundant and one side begins parroting back arguments to the other. - Yeah, I've read some of the endless early "debates" with bard32. I wasn't aware that I had done so and will try to guard against doing so in the future. I can only attempt to refute concerns, one by one, as they are posted by my readers.

After reading through the posts, I have to agree with the majority on here, that this TL is ASB. - This kind of a response is exactly what I find so frustrating here. By presenting no sourced and detailed points of dis-agreement with my scenario, you allow me no opportunity to research and present any kind of a counter-arguement. There is no way for debate, discussion or learning, thru the exchange of ideas, to proceed on between us.

Two short posts ago FlyingDutchman presented a sourced list of items wrt my scenario that he disagreed with. I was able to respond fairly quickly with a source and further explanation of my scenario, in an attempt to convince him of the feasibility of that proposal. Maybe I'll succeed, maybe I won't but at least FlyingDutchman and I can have a civilized discussion about my AH.

Other than this message, how can I possibly respond further to you on this topic since you've given me no explanation at all of your negative pov ?

Just an easy and fast to type "ASB" label.

Isn't the purpose of posting/reading at a place titled "Aternative History Discussion Board" to actually discuss alternative histories ?
 

robdab2

Banned
Exploding Warships ...

... not raising an alarm seems to be a recurring criticism of my AH scenario so I'd like to draw everyone's attention to the historical example of the USS West Virginia (moored just a 1/2 a mile from USS California) at Pearl Harbor on Dec.7'41.

Prange records on page #506 of his book "At Dawn We Slept" that, "On West Virginia, Ensign Roland S. Brooks saw what he thought to be an internal explosion on California and ordered 'Away Fire and Rescue Party'. Actually the flame and smoke came from a burning hanger on Ford Island". Which was itself about a single mile away from West Virginia.

And this while Japanese planes plainly marked with 'red meatballs' flew by overhead/beside, dropping bombs/torpedoes and straffing. Three good clues if ever there were any.

It would seem common enough for accidents to affect USN vessels that an 'Away Fire and Rescue Party' order was already a part of their standard drill ?

Even if noticed by anyone inside PH, then some 9-11 miles away, would the sight of a flash from the USS Ward's position automatically have been cause for an attack warning to flash around Oahu ? Historically there was no on-shore reaction to her 12 cannon shots or to the 14 depthcharges that were used. Or would the watcher have wasted time investigating/confirming and giving another 'Fire and Rescue Party Away' order, instead ? If hit by one or two minisub torpedoes Ward might have burned and sent up a huge cloud of smoke or, she might not have caught fire at all.

I've already posted an account of Captain Outerbridge's (of USS Ward) lack of alarm at the sounds of combat coming from PH an hour after his just having sunk a Japanese minisub, so this second example just supports the idea that no US defenders were at all expecting a war to start that morning.

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My apologies for the duplicate postings #41 and #42. I don't know how I did that and so don't know how to "fix it" ?
 
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... and they still failed to sink the blockships across the channel when the current turned them parallel to the channel. - Have you not answered your own question here ? My blockship proposal initially includes the installation of extra anchors on Tatuta Maru so that she can be securely anchored in the correct blocking position rather than being left to swing at the mercy of wind, current or tide.
You're still not getting my point.
The Brits had and have practically eons of experience with fireships, blockships and other ancient techniques to annoy their enemies. Extra anchors or not, the chance of success is too small with a single large ship while you run the risk of compromising the entire attack on Pearl.


AFAIK Pearl Harbor, which is NOT the outlet of any major river, has only a 1-2 knot tidal current flowing in or out of it (depending on the tide's flow direction at any given time of day) with slacktide times having no current at all. And no, I haven't looked up the tide direction info for Dec.7'41 except to note that the usual tide rise and fall range for Oahu is/was only 1'.
Neither is Dunkirk AFAIK. As I wrote in my first post, Dunkirk is a midget port compared to both ports on Pearl. There is however some tide at Dunkirk, probably more than 30 cm.

I did a quick google search and found a nice account of the two Dunkirk multiple blockship
events at http://books.google.ca/books?id=UqE...g=GiffQnuwALPR5e6jUVTakCam0O0&hl=en#PPA119,M1
The first thing that I noticed was that the blockships employed there were tiny, at less than 2,000 tons as compared to Tatuta Maru's 17,000 tons.

My source for this is Walter Lord's "The miracle of Dunkirk" (yes, original title) - Sorry but I don't own that one. Will try to find a copy when I visit my reference library over the weekend though. Thanks for posting your source since that practise seems to be a rarity here.
I found mine for 5 euro's; books overhere are very expensive, even mainstream books cost at least 15 euro, so I found it a bargain.

Your source does seem better.

But I also think it'll be easier to have 5/6 blockships to block a single exit, then to have 1 blockship to block 1 exit. So even though the Brits had room for error, they still bungled and as mentioned above, the British aren't exactly novices at blockships and the likes.
They also had more manoeuvrable destroyers to aid in putting the blockships exactly right, while your (huge) ship doesn't have any tugs or anything like it.

So I doubt any planner would suffice with a single blockship; you'd need several to even stand a reasonable chance of (partly) blocking the channel.- A good point but look at the dredged widths and depths of that channel and then at the length of the Tatuta Maru. As long as she sinks even somewhat sideways across that channel there is only room for US destroyers and smaller to inch past her and even that, very carefully and slowly. Which is why my proposal suggested that any IJN minisub still carrying it's torpedoes after USS Ward was ambushed should follow the Tatuta Maru up the PH entrance channel. There to take up another ambush position near the TM so as top be able to spear any USN warship attempting to slowly creep past her blocking position in that channel. Why use up your own scare merchant ships if you can "persuade" the USN to contribute some of it's warships for that task ?
No, your blockship needs to sink perfectly sideways and even then you leave enough room for torpedoboats, ASW trawlers and even DD's to pass, as you mentioned yourself.

Your remark about leaving subs behind as a sort of suicidesquad shows way too much hindsight. Why not improvise a mini-sub base in that blockship while you're at it?
What are your sources to prove the Japanese were 100% aware of the American lack of security?

Also mini-subs, just like the Italian pigs, are extremely vulnerable and I doubt their usefullness in a channel whose water is murky after all the explosions/fires etc. If the Japanese sink a blockship, the Americans will asume there will also be a crew running amok somewhere.
A few handgrenades in the water after periscopes and strange waves have been spotted will probably suffice to destroy the minisubs, they won't even need depthcharges.


She was salvaged (years) later, despite (not) being 'incinerated' by flaming fuel after already being hit by 2 bombs and having a lousy watertight integrity. - And what is your point ? We already know that Japan cannot win a long duration war against the US mainland's strategic production capabilities. Either she somehow forces the US to the ceasefire table quickly or the A-bomb will finish her, eventually, as per history.
My point was that despite being threatened by flaming fuel, California wasn't lost and neither would any decent sized warship.

You're also assuming that if the Japanese manage to hit a single oilfarm, they'll succeed in releasing every last drop of oil in all the tanks in that oilfarm.
Doesn't each oilfarm consist of several oiltanks which have earthen walls around them? If so, you can hit and destroy a tank, but as long as it doesn't start to burn, you'll even be able to rescue a part of that oil.
Also if you manage to torch one tank, you'll have no guarantee the other (burst) tanks will also burn.
 

Markus

Banned
What are your sources to prove the Japanese were 100% aware of the American lack of security?

My point was that despite being threatened by flaming fuel, California wasn't lost and neither would any decent sized warship.

1. The Japanese actually overestimated the Americans, they thought they might loose as many as three carriers.

2. California was sort-of sunk so fast, because all watertight doors had been opened for an inspection.
 
1. The Japanese actually overestimated the Americans, they thought they might loose as many as three carriers.
exactly!
Who could have known the low readiness and all other things?
If hindsight is used, then the Japanese could have tried to land airplanes at the airbases (like they did much later with suicide squads) to destroy planes. The low readiness coupled with the planes parked together, could have meant that an SAS-style attack would be extremely successfull.

2. California was sort-of sunk so fast, because all watertight doors had been opened for an inspection.
Mentioned in my first post:
having a lousy watertight integrity
 

robdab2

Banned
Blockship continues ...

FlyingDutchman, in replu to your post #44,

You're still not getting my point(s). - Oh, I "get" them alright, I just don't agree with most of them.

The Brits had and have practically eons of experience with fireships, blockships and other ancient techniques to annoy their enemies.- As I've already posted, I don't own a copy of your source so you'll have to tell us what it says about why/how the Brits screwed up their blockships at Dunkirk. I can't read your mind to get the facts.

Extra anchors or not, the chance of success is too small with a single large ship while you run the risk of compromising the entire attack on Pearl. - In your (so far unsubstanciated) opinion.

Let me point out that my scenario is limited in the number of Japanese blockships sent by the HISTORICAL fact that the US had embargoed Japanese merchant shipping in its territorial waters for some time PRIOR to the Pearl Harbor attacks. The US government in Washington DID historically give the Tatuta Maru permission to pass thru Honolulu on Dec.9'41 while on its way from Yokahama to San Francisco so, my scenario uses just ONE blockship (surprise, surprise), the 17,000 ton Tatuta Maru, advanced by just two days.

Sure, I'd like to include more blockships BUT if an American search plane saw 2,3,4,5 or 6 Japanese ships traveling towards Oahu when it expected to see ONLY the Tatuta Maru on course and schedule, an alarm would have been raised.

Your source does seem better. - Since I don't have access to yours, I'll just take your word for it.

Mine indicates that a magnetic mine sank one of the three Brit blockships outside of Dunkirk harbor, that another of the blockships tried a last minute change of position to replace the one sunk by the mine, that there was a strong current running (doesn't say from where or why) and that there was artillery shelling of the harbor going on, at the same time. Did I mention that it was AT NIGHT also ? I'm told that its harder to plot a ship's position accurately, in the dark, with shell flashes all around but never having been in that position myself, I don't know that to be fact or fiction. But, I have my suspicions. LOL.

My scenario would certainly include shelling of the Tatuta Maru by the 2x3" examination battery but otherwise it's:
1.) in daylight
2.) has no strong currents
3.) has no minefields magnetic nor otherwise (although if USS Ward doesn't get torpedoed by an IJN minisub then things will get really ugly, really fast for the Tatuta Maru.)

So even though the Brits had room for error, they still bungled and as mentioned above, the British aren't exactly novices at blockships and the likes. - Other than the source that I provided, I have no idea as to how/why they screwed it up, twice. Maybe too much long term interest in "rum, sodomy and the lash" ?? Or too many defective lima beans ?
Since you raised the point, what does your Lord source have to say on the matter ?

No, your blockship needs to sink perfectly sideways and even then you leave enough room for torpedoboats, ASW trawlers and even DD's to pass, as you mentioned yourself. - And just why would the Kido Butai, with 6 carriers worth of warplanes, 2 battleships, 2 heavy cruisers, some 9 destroyers and 30 IJN submarines in support, really care at all about 6 PTs (less if oiler Ramapo gets hit since three of the 6 PTs were already loaded on her decks or the wharf beside her for transit to the Philipines), some ASW trawlers (sorry but did the US have any of those inside PH on Dec.7'41 ?) and a few US destroyers that might get past the remaining Japanese minisubs ? With the first US DD being torpedoed, I'd doubt that any more would risk the squeeze past the Tatuta Maru. And all of that murky water that you mentioned would be good for hiding lurking IJN minisubs from the watching eyes of US PBYs circling overhead.

Promotion boards don't look kindly upon loosing first commands while taking stupid risks.

Your remark about leaving subs behind as a sort of suicidesquad shows way too much hindsight. - How so ? Historically one of the IJN's 'mothership' submarines was scehduled to pick-up the minisub crewmen so no "suicidesquad" mission was included in my scenario either. Once their torpedoes were exhausted each Japanese minisub would be free to leave the PH ship channel for a crew pick-up at the historical location. Hopefully 2-3 days later ...

What are your sources to prove the Japanese were 100% aware of the American lack of security? - I wouldn't say 100% lack but Prange's "ADWS" details much of it. A google search for Yoshikawa will provide more info on his pre-war intell gathering efforts.

Also mini-subs, just like the Italian pigs, are extremely vulnerable and I doubt their usefullness in a channel whose water is murky after all the explosions/fires etc. - IIRC the Italian "pigs" were just a manned torpedo (with controls) straddled by two divers ? The IJN minisubs were a good deal larger and actually were a dry pressurized interior minisub, fitted with a periscope to rise above all of that dirty, murky harbor water. Again, I have no doubt that a google search prior to entering a discussion might prove educational.

A few handgrenades in the water after periscopes and strange waves have been spotted will probably suffice to destroy the minisubs, - Sigh ... have you read absolutely nothing about the history of the day ?

My point was that despite being threatened by flaming fuel, California wasn't lost and neither would any decent sized warship. - My point is that had you read a book on the subject you would know that the flaming oil NEVER REACHED the USS California. A combination of wind shift and prop wash was used to keep the oil away WITHOUT it reaching the battleship. BUT she was ordered abandoned because of the THREAT that the flaming oil presented, well BEFORE it even reached her. Her Captain realized the very real threat, even if you do not.

You're also assuming that if the Japanese manage to hit a single oilfarm, they'll succeed in releasing every last drop of oil in all the tanks in that oilfarm. - Well I believe that I've mentiioned that there were 4 seperate oil tankfarms but yes, having witnessed the total destruction by fire of 8 out of 8 large, modern, bermed, foam system protected oil tanks in Vladivostock, that is exactly what I am saying. Yet another google search will reveal many internet photo sequences of progressively spreading oil tank fires. They are the devil's own spawn to extinguish, even today, let alone 66 years ago, with the Japanese still trying to bomb/straffe you at the same time.

... as long as it doesn't start to burn ... - Is the critical potion of your arguement. I seem to remember seeing LOTS of historical PH photos showing "flaming fuel on the water" views. If it can be lit on the water, why would it not burn on land when the Japanese would be trying to set it afire ?

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in reply to your posting #46,

...the Japanese could have tried to land airplanes at the airbases (like they did much later with suicide squads) to destroy planes. The low readiness coupled with the planes parked together, could have meant that an SAS-style attack would be extremely successfull. - True enough except that would have been a suicide attack when none were officially ordered so early in the Pacific War. I suppose that one could argue that sympathetic Oahu residents of Japanese ancestry (40% of the population there) might have been persuaded to hide any survivors but realistically, how would any such have gotten back to Japan after the hornet's nest at PH was "poked" ?

The Japanese did historically have 12 G3M2 Nell bombers that had been converted to civilian airliner status pre-war and had the range needed to carry 10 or so "commandoes" (possibly JSNLF paratroopers) on a one-way flight from Kwajalein (Roi) to Oahu but over ocean navigation, at night, would have been life threatening. And historically, Enterprise's air search radar might have picked them up in the darkness, while still about an hour SW of Oahu. Not that the Japanese could have known that, without hindsight.

Its already been proposed (by me) just recently on another board.
 
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Let me point out that my scenario is limited in the number of Japanese blockships sent by the HISTORICAL fact that the US had embargoed Japanese merchant shipping in its territorial waters for some time PRIOR to the Pearl Harbor attacks. The US government in Washington DID historically give the Tatuta Maru permission to pass thru Honolulu on Dec.9'41 while on its way from Yokahama to San Francisco so, my scenario uses just ONE blockship (surprise, surprise), the 17,000 ton Tatuta Maru, advanced by just two days.

I read the entire thread fridaymorning-ish before replying the first time, so I am aware that there's only one ship to be sent. My reasoning was that you need several, so the operation isn't possible.

Mine indicates that a magnetic mine sank one of the three Brit blockships outside of Dunkirk harbor, that another of the blockships tried a last minute change of position to replace the one sunk by the mine, that there was a strong current running (doesn't say from where or why) and that there was artillery shelling of the harbor going on, at the same time. Did I mention that it was AT NIGHT also ? I'm told that its harder to plot a ship's position accurately, in the dark, with shell flashes all around but never having been in that position myself, I don't know that to be fact or fiction. But, I have my suspicions. LOL.
As I said the first time, it was tried twice.
The first time was at night (under undirected artilleryshelling), the second around dawn, but don't have Walter Lord's book here. BTW it's a thin (280 around pages) book which mainly describes the British side. I haven't compared it with other books, but it could possibly be partial.
The exact how and why of the failures is very briefly described, except that it's apperently more difficult as mere landlubbers as me can understand.

It seems to me you're downplaying the difficulties the Japanese would have a bit, or at the very least the planned difficulties they could concieve.
I'd think that the whole attack is already unconventional and difficult enough as it is. The Japanese at least had the succeeded British example at Toranto for the strike part, but most attempts with blockships in WWII were complicated at the very least.

It could help if you could provide some more examples of successfull blockships in enemy ports.
There aren't that many I know of, most of them British.
WWI; Zeebrugge, first attempt failed, second successfull.
http://www.legionmagazine.com/en/index.php/2006/03/valour-in-the-navy/
WWII; not exactly to block a port, but an explosive blockship to destroy a lock. here; http://en.wikipedia.org/wiki/St._Nazaire_Raid

Both time it took enormous casualties and lots of naval and land support. This isn't something attempted by a single ship and a few men.

BTW, where did that Japanese ship come from? Did it come straight from Japan, so it could have loaded a military crew, cement, explosives etc? If it came from a neutral port or the USA this would be dangerous. You'd risk comprimizing your whole strike.
 

robdab2

Banned
FlyingDutchman,

My reasoning was that you need several, so the operation isn't possible. - Several blockships would have guaranteed that the operation would have raised an alarm. On ALL three previous HISTORICAL Japanese repatriation ship visits to Honolulu, each Japanese cargo-liner had been met and "buzzed" by a US PBY at 400 miles out of Oahu and again at 200 miles out. ALL THREE TIMES PREVIOUS. The Yanks weren't idiots, and neither would be my Japanese. Just one blockship. Although I thought about giving her some minelaying capability but decided that there was too much explosion risk due to the 2x3" gunfire issue. Plus, Japanese mines in the PH ship channel would prevent safe minisub operaton there.

The exact how and why of the failures is very briefly described, except that it's apperently more difficult as mere landlubbers as me can understand. - Another look at my source says that a gap at the bank of 100-120 feet was left open but that this was "shoal water" due to sloping banks. So was the British blockship mission at Dunkirk really a failure ? Yeah, a coastal freighter might slip in or out at high tide but no German heavy cruiser would be able to use the Port of Dunkirk.

It seems to me you're downplaying the difficulties the Japanese would have a bit, or at the very least the planned difficulties they could concieve.- When I study the historical hurdles that they DID overcome, in the very short times that they had to do so, I am convinced that they would "rise to any occassion."

Both time it took enormous casualties and lots of naval and land support. This isn't something attempted by a single ship and a few men. - Sure it is. Surprise is a HUGE force multiplier. And technically, my scenario largely plays out in PEACETIME with no shooting expected until it actually happens.

It could help if you could provide some more examples of successfull blockships in enemy ports. - Hey mon, it's not up to me to do your research for you ! A google.com search for "Japanese" and "blockship" turns up Japanese blockship examples back to the Russo-Japanese war and up to 1945, with lots in between. A long and cherished blockship tradition from a nation of seafaring traders and fishermen.

BTW, where did that Japanese ship come from? Did it come straight from Japan, so it could have loaded a military crew, cement, explosives etc? - my last post to you contained my, "The US government in Washington DID historically give the Tatuta Maru permission to pass thru Honolulu on Dec.9'41 while on its way from Yokahama to San Francisco so, my scenario uses just ONE blockship (surprise, surprise), the 17,000 ton Tatuta Maru, advanced by just two days."

Yokahama was/is a major Japanese port.
 
FlyingDutchman,

My reasoning was that you need several, so the operation isn't possible. - Several blockships would have guaranteed that the operation would have raised an alarm. On ALL three previous HISTORICAL Japanese repatriation ship visits to Honolulu, each Japanese cargo-liner had been met and "buzzed" by a US PBY at 400 miles out of Oahu and again at 200 miles out. ALL THREE TIMES PREVIOUS. The Yanks weren't idiots, and neither would be my Japanese. Just one blockship.

Just one blockship means a very small chance of success. So the operation won't go ahead. At least that's my opinion.

The exact how and why of the failures is very briefly described, except that it's apperently more difficult as mere landlubbers as me can understand. - Another look at my source says that a gap at the bank of 100-120 feet was left open but that this was "shoal water" due to sloping banks. So was the British blockship mission at Dunkirk really a failure ? Yeah, a coastal freighter might slip in or out at high tide but no German heavy cruiser would be able to use the Port of Dunkirk.
For the gazillionth time: dunkirk is a very small port!!!!!!!!!
The Germans control the entire French-Atlantic/Channel coast. Why would they use a miniature port? Just because the British used it to escape from teh continent? No, the Germans would use Brest, Bordeaux, Cherbourg etc etc which they did historically!

It seems to me you're downplaying the difficulties the Japanese would have a bit, or at the very least the planned difficulties they could concieve.- When I study the historical hurdles that they DID overcome, in the very short times that they had to do so, I am convinced that they would "rise to any occassion."
Both time it took enormous casualties and lots of naval and land support. This isn't something attempted by a single ship and a few men. - Sure it is. Surprise is a HUGE force multiplier. And technically, my scenario largely plays out in PEACETIME with no shooting expected until it actually happens.
Sure, but suprise or no suprise, if all blockships attempts untill then are done with extensive naval and land support (as mentioned earlier) why would the Japanese suddenly attempt to do it without such support?


Hey mon, it's not up to me to do your research for you ! A google.com search for "Japanese" and "blockship" turns up Japanese blockship examples back to the Russo-Japanese war and up to 1945, with lots in between. A long and cherished blockship tradition from a nation of seafaring traders and fishermen.
What???
This is your idea, so you have to try to prove your point, which you can do by showing historical examples. I was just trying to help you there... :rolleyes:
BTW, where did that Japanese ship come from? Did it come straight from Japan, so it could have loaded a military crew, cement, explosives etc? - my last post to you contained my, "The US government in Washington DID historically give the Tatuta Maru permission to pass thru Honolulu on Dec.9'41 while on its way from Yokahama to San Francisco so, my scenario uses just ONE blockship (surprise, surprise), the 17,000 ton Tatuta Maru, advanced by just two days."

Yokahama was/is a major Japanese port.
Just mentioning Yokohama would have sufficed. That means the Japanese will be able to load Tatuta Maru with whatever they want; cement, mines, explosives etc.

Conclusion;
You'll only have one attempt, so I'd solely look at the first attempt at other blockship operations.
1. Zeebrugge WWI failed first time
2. Dunkirk WWII failed first time
3. St.-Nazaire WWII, no true blockship but something looking like it, succeeded.

That leaves 1 success out of 3 times. But your operation might be under just as heavy opposition as any of the above mentioned, the Japanese just can't count on complete American suprise and no adequate manning of defenses etc.
You're even dropping the land and naval support part, so any Japanese staffofficer will logically think your chances will be even lower than 1 in 3.

You're still risking the entire strike for a slim chance of success.
What if the Americans board your ship and see the preperations for the scuttling? If your blockship really is as unconspicuous as you want it to be, it'll have to be completely unprepared, so no military crew or charges set untill the last moment for example. Your cargo can't be much, as the Americans will notice a low freeboard without even having to come aboard. Anything looking out of the ordinary for an empty ship sent to collect civilians would have to be avoided.
 
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robdab2

Banned
FlyingDutchman,

So the operation won't go ahead. At least that's my opinion. - To which you are surely entitled, just as I am entitled to disagree with your opinion.

The Germans control the entire French-Atlantic/Channel coast. Why would they use a miniature port? - Don't know, don't care. I'm here to discuss a hypothetical Japanese blockship at Oahu. You are the one that keeps on about Dunkirk, not me. One question for you though ... if Dunkirk was so unimportant a port then why did the British make not just one, but rather two seperate attempts to block it up ?

... if all blockships attempts untill then are done with extensive naval and land support (as mentioned earlier) why would the Japanese suddenly attempt to do it without such support? - Ah, because it was intended to be a surprise.

And if the entire Pearl Harbor raid by the KB (6 carriers, 2 battleships, two heavy cruisers, a light cruiser, 9 destroyers and a whole bunch of tankers) with nearly 30 submarines and 5 minisubs aiding isn't "extensive naval support" then how would you define that term ?

In fact as far as land support goes, you do make a valid point in that I had always intended for such a blockship effort to be a part of an AH Japanese invasion of Hawaii but wanted to discuss the scenario in isolation so that the blockship plan didn't get ignored amid the howls of anti-invasion protests. i'll get to that, later.

This is your idea, so you have to try to prove your point, which you can do by showing historical examples. - To a point I suppose but the concept falls short, ie Taranto serves an example for the air attack on Pearl Harbor and there was an air dropped WW1 torpedo attack that serves as an example for Taranto but what serves as an example for that WW1 air dropped torpedo attack ? Every method of warfare has it's own FIRST USE. Perhaps my blockship at PH would have been just such a first, unsupported by ground troops effort ? Or not.

Or do you suppose that the A-bomb attacks on Japan could NOT have happened because no one had ever dropped an A-bomb on an enemy previously ? That was a first wasn't it ?

I was just trying to help you there... - With this kind of help, who needs enemies ?

Just mentioning Yokohama would have sufficed. - Which I did three, no make that four, times now.

... so I'd solely look at the first attempt at other blockship operations. - Perhaps it might be more useful to look at Japanese blockship efforts in the Pacific and related regions rather than at the attempts of other nations, on other continents ? An apples to apples comparison rather than an apples to oranges effort.

the Japanese just can't count on complete American suprise and no adequate manning of defenses etc. - And why not ? Three previous Japanese repartriation ship trips thru Honolulu (including the first by the Tatuta Maru herself) had gone off in an identical fashion and with no undue American interference. The Japanese spy Yoshikawa was roaming Oahu freely and had indicated no greater signs of US alertness than existed when the first three cargo-liners passed thru. What possible reason do you have for your suggestion that the US would be any more alert on the fourth voyage ? Other than hindight or knowledge of my scenario proposal that is ?

You're still risking the entire strike for a slim chance of success. - I think that it had a large chance of success. No more risk than Yamamoto took by ordering 5 minisubs to sneak into Pearl Harbor itself. At least two of those were spotted and one was actually sunk so that SHOULD have alerted the US defenders, but somehow, did not. My scenario poses no greater threat that the historical Japanese efforts.

What if the Americans board your ship and see the preperations for the scuttling? - Did you not read my scenario at all ? USS Ward will be (hopefully) torpedoed as she slows to send an inspection team/pilot to board the Tatuta Maru. If the Ward IS sunk, there will be no US inspection team. If the Ward is NOT sunk, there will be no inspection team either, just lots of gunfire and US destroyer torpedoes. You just don't get the concepts of a gateguard, a sea exclusion zone and naval combat do you ?

Anything looking out of the ordinary for an empty ship sent to collect civilians would have to be avoided.- No shit, Sherlock ?

In actual fact if you knew anything at all about repatriation ship voyages you would know that the US authorities on Oahu would have already been sent (as they were for the first three voyages), a complete list of US citizen passengers being returned from Japan to the United States. Once in San Francisco a number of Japanese citizens would be picked up for the return trip to Japan.

While USS Ward was slowly approaching Tatuta Maru, she would expect to see several "passengers", both male and female, lining that ship's railings. So some appropriately dressed (and made-up) Japanese crew "volunteers" would be required to support the deception until the minisub torpedoes arrived.

Historically NO repatriation ship's cargo, other than food supplies and the passenger's belongings were approved for transport into/thru US waters.
 
Calm down. Telling people what they want to hear instead of what one thinks it's true isn't helping them. It works the other way around.
The only naval support the Tatuta Maru would have are the minisubs and, perhaps, the aircraft. The destroyers, BBs, subs and so on are too far away escorting the carriers to do anything for the Tatuta Maru.
First times happens, and usually shows the errors in the theory. Aerial bombing of cities against enemy oposition is one of the best examples of that.
OTOH, for the crew of the Tatuta Maru that would be a suicide mission. Are they suppposed to evacuate or their only option is to become POWs (or be shooted on sight by furious American soldiers)
And is the Tatuta Maru supposed to be carrying American citizens? That can avoid that land battery from shooting at her, meaning she'll have an easier time getting in the correct position to block the harbor
 

robdab2

Banned
juanm182, in response to your posting #52,

Telling people what they want to hear instead of what one thinks it's true isn't helping them. - Agreed that constructive criticism is useful since attracting some of that was the reason for my posting the thread in the first place. But, I'd expect a response that accurately reflects the scenario, from someone who devoted some amount of thought to it.

The destroyers, BBs, subs and so on are too far away escorting the carriers to do anything for the Tatuta Maru.- And what would you propose that they do to help her in any case ? Without revealing the entire surprise that is ? Certainly some 1st wave KB warplanes could aid by straffing the open topped US 2x3" examination gun battery (as I've already proposed) but the timing for that is critical.

Just as historically they were too far away to aid the 5 Japanese minisubs either. Yet those minisubs were still ordered to sneak into PH. Why do you attempt to hold my scenario to a higher standard than the Japanese historically followed ?

OTOH, for the crew of the Tatuta Maru that would be a suicide mission. Are they suppposed to evacuate or their only option is to become POWs (or be shooted on sight by furious American soldiers) - I ask you in return, what measures for crew escape did the Japanese historically plan for their PH attackers ?

The minisub crews were to rendevous with a "mothersub" IF they somehow got back out of PH, alive. What would you estimate the chances of that being ? Considering that only one minisub crewman of the ten survived the attack and that one only because his minisub NEVER ENTERED PH due to a compass problem. He didn't get anywhere near the rendevous island.

How were any KB pilots shotdown over Oahu to return to Japan ? Answer - they weren't. They were to die honourably for their Emperor (several did do suicide dives) while resisting capture.

Once again, I suggest that you are holding up "my" scenario's Japanese attackers to higher standards than the Japanese used, historically.

And is the Tatuta Maru supposed to be carrying American citizens ? - Historically she was carrying several (soon to be very disappointed) US citizens when she turned around in mid-Pacific at midnight on Dec.6-7'41. The Japanese civilian crew was previously armed with some 20 handguns just in case any US passengers tried to rush the ship's radio room.

If you had READ my just previous response then you would know that my scenario proposes that several Japanese military crewMEN would be dressed and "made-up" appropriately to look like male and female civilian passengers, from a distance. Being that many Hawaiian nisei were returning from advanced education in Japan at this time, such deception should have worked, at least until USS Ward was torpedoed.

That can avoid that land battery from shooting at her, meaning she'll have an easier time getting in the correct position to block the harbor. - Ah, no, not at all. Once the US gunners finally connect a sinking Ward with the 17,000 ton Japanese cargo-liner rushing up the PH entrance channel, there is going to be 2x3" US coastal artillery gunfire, passengers be damned.

The only question is just how long it will take the US gunners to realize that "something is just not right" with the Ward ? Peacetime ship explosions and fires did occassionaly happen by accident, afterall. I've already posted the reaction of the USS West Virginia to what she thought was an accidental fire on the USS California, even while KB warplaes were in the air above both of them.

The combination of a smoking/sinking WARD and a cargo-liner rushing the channel would indeed be hard to ignore forever. I'd expect some hesitation ("Maybe that innocent liner is rushing away from a torpedo attack that hit Ward by accident instead ?", comes to mind) but eventually, US gunfire.

Yet too small a calibre to be quickly effective. 3" vs a submarine, a PT or even a 1,500 ton destroyer might be ok but against a 17,000 ton high speed monster inbound ? Not so much. IMO.
 
And if the entire Pearl Harbor raid by the KB (6 carriers, 2 battleships, two heavy cruisers, a light cruiser, 9 destroyers and a whole bunch of tankers) with nearly 30 submarines and 5 minisubs aiding isn't "extensive naval support" then how would you define that term ?
The destroyers, BBs, subs and so on are too far away escorting the carriers to do anything for the Tatuta Maru.- And what would you propose that they do to help her in any case ? Without revealing the entire surprise that is ? Certainly some 1st wave KB warplanes could aid by straffing the open topped US 2x3" examination gun battery (as I've already proposed) but the timing for that is critical.

Just as historically they were too far away to aid the 5 Japanese minisubs either. Yet those minisubs were still ordered to sneak into PH. Why do you attempt to hold my scenario to a higher standard than the Japanese historically followed ?
:rolleyes:
Once again, I suggest that you are holding up "my" scenario's Japanese attackers to higher standards than the Japanese used, historically.
I'm not holding up the scenario. I inquired if you though about the flaws such a plan has (any plan will have some kind of flaw). Question, did the minisubs crews knew before entering Pearl that they wouldn't be getting out of there alive? Or did they though they still had a chance of seeing their families ever again? Beliving they have a chance to live might make a difference. Your crew knows that their best possible scenario is to remain pow for the duration of the war. They might do it anyways, but it worth analizing.
That can avoid that land battery from shooting at her, meaning she'll have an easier time getting in the correct position to block the harbor. - Ah, no, not at all. Once the US gunners finally connect a sinking Ward with the 17,000 ton Japanese cargo-liner rushing up the PH entrance channel, there is going to be 2x3" US coastal artillery gunfire, passengers be damned.

The only question is just how long it will take the US gunners to realize that "something is just not right" with the Ward ?
Would they connect the sinking Ward with the cargo liner? Probably. But the cargo liner might precisely claim they're running away from hostile subs. The gun crew won't open fire on American citizens in peacetime without consulting their superiors.Their superiors then won't be able to ignore the prescence of hostile subs in PH and might even order a warnign shot across the bow. But will they kill their fellow countrymen? That hesitation (and the japanese radio operator/captain acting as a panicked man) might give the IJN enough time to either strafe the battery or for the cargo liner to position herself to do whatever they need to do to block the harbor, if at all possible (with I have no idea as, I said before, I'm not a naval expert) How much time is it between the sinking of the Ward (if sucessfull) and the Tatuta Maru getting into position to block the harbor?
 

robdab2

Banned
juanm182,

Question, did the minisubs crews knew before entering Pearl that they wouldn't be getting out of there alive? - Yes. there are post-war interviews with both the surviving minisub crewman and his overall unit commander (who not very bravely stayed on board the mothersub) where both discussed their views that the crews would be unlikely to survive. The surviving crewman relates that the 10 crew, when talking among themselves vowed to stay aboard to ensure that the demolition charges would really wreck their minisubs, so that the Americans would get no good intel.

Nail and hair clippings were collected from each crewman, for return to their families, prior to minisub seperation from each mothersub. They didn't expect to return, alive.

The gun crew won't open fire on American citizens in peacetime without consulting their superiors. - Maybe but Kimmel had issued orders wrt possible blockship attempts. The Americans were well aware that blocking the entrance was a possibility and so would not have held fire for long as they noticed the Tatuta Maru increasing her speed towards them. Escape from a submarine attack was possible in several other directions than up the PH entrance channel, afterall.

How much time is it between the sinking of the Ward (if sucessfull) and the Tatuta Maru getting into position to block the harbor? - Its hard to know for sure how long Ward would take to sink (certainly faster if hit by two torpedoes rather than just one) but after she was hit (with most guns and torpedoes then likely out of action) I'd guess that Tatuta Maru would need about 30-45 minutes to accelerate to top speed, get to and up the channel (somewhere between 4.5 and 6.5 nmiles at 20 knots), slow down and finally, drop anchors.

While being pounded by 2x3" gunfire.

A standby US DD was always positioned at the top of the PH entrance channel (just off of Hospital Point) with orders to come to the assistance of the gateguard DD on 1 hours notice but I think her to be too far out of position in this scenario. She might reach Tatuta Maru once that liner was already anchored and settling but this would be far too late to prevent that blockship from accomplishing it's mission.

The Japanese secret weapon here was the 5 minisubs that were NOT known to the US military. The USN would not expect IJN full sized submarines to be able to operate secretly in the shallower waters near the PH entrance channel and so USS Ward, locked into her patrol square, would have no idea that she was being stalked by 5. The gateguard US DD was normally expected to stop any blockship with her guns and torpedoes but the minisubs allowed her to be neutralized, without warning. Historically, the Japanese chose not to use them in that way but my scenario proposes, what if ...
 
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robdab2

Banned
A Correction to my Correction ...

I have just heard back from the Honolulu Harbor people who informed me the on Dec.7'41 that port was indeed only dredged to 27' as I first reported here.

A plan to dredge to 38' was proposed in 1938, hence the harbor map that I saw a couple of weeks ago, but due to budget constraints, that work was not begun until mid-1942. My correction needs to be corrected.

27' not 38' in Honolulu Harbor.

So, no fuel for a thirsty Enterprise or Lexington could be had from that source had PH's fuel storage tanks been destroyed by the Japanese.
 

robdab2

Banned
For any so interested in a Pearl Harbor blockship, I visited the College Park, Maryland Archives last week and discovered that my previous information wrt the US CAC examination batteries at Pearl Harbor was incorrect for Dec.7'41.

I had previously thought that a 2x3" battery and a 2x6" battery, both at Fort Kamehameha had shared that duty but I have just discovered that they were only assigned that task AFTER Dec.7'41, not before that date.

Prior to and during Dec.7'41 the CAC battery charged with covering the entrance channel into Pearl Harbor was in fact located on the Sand Island Military Reserve, at Honolulu Harbor, some 5 miles to the east. Located there were 4x155mm guns on circular poured concrete "panama mounts", a 60" serchlight (and generator) mounted on a 60' tall steel strut tower and 4x3" pedestal mounted AA guns. The gunnners for all 8 were billeted about 200 yds from their artillery although none were actually sitting behind their sights first thing that morning. The AA gunners were not trained in anti-shipping fire so that task would have fallen to the 4x155mm gunners while they were protected from air attack by the 4x3" AA gunners.

My Tatuta Maru blockship would have received 4x155mm fire to her stern as she charged up the PH entrance channel. Considerably worse than the 2x3" (but much closer) fire that I had expected her to withstand. Thankfully the range would be increasing by the minute.

I am currently investigating the Japanese use of "smoke candles" or floats in screening their beach invasion landings in the hope that my Tatuta Maru might drop several off of her stern in order to create her own short term smokescreen on the water's surface ?

please see http://www.lonesentry.com/articles/jp-use-smoke/index.html for two that might work.
 
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Okay lets assume that

*The US doesn’t get suspicious when the Tatuta Maru arrives 2 days early.
*The US either doesn’t search the Tatuta Maru or does and no one notices something suspicious.
*And the minsubs instead of being scattered by currents, successfully converge on USS Ward.
*And the minisubs succeed in sinking USS Ward.
*And USS Ward sinks too fast to get off a radio warning.
*And no one notices or cares that USS Ward has broken up and sunk.
*And no one at Pearl Harbor notices or cares that the Tatuta Maru is steaming full tilt into the channel and then turning sideways.
*And the Tatuta Maru sinks swiftly in exactly the right spot.

Then:
*The US carriers are still outside Pearl, so Nagumo still doesn’t launch the third wave of planes.
*All but the largest US ships can still freely exit the channel.
* US Navy divers have their 20,000 hours logged under water with zero visibility increased by a small amount.
*The channel is cleared long before the damaged battleships are ready to be moved to repair facilities.
 
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robdab2

Banned
Fiver,

If you'd re-read the entire thread you'd see that most of your assumed points have already been answered.Wrt the "then" items:

*The US carriers are still outside Pearl, - and desperately short of fuel so Nagumo still doesn’t launch the third wave of planes.- Why not ? He can keep 50 Kates loaded with torpedoes and some Zeros in reserve while still launching 200+ 3rd wave warplanes at Oahu targets
*All but the largest US ships can still freely exit the channel.- With probably 4 (totally unknown to the US) minisubs lurking in the entrance channel, in support of a now sunken Tatuta Maru blockship, this would be very risky for the first two or three US warships that tried it. Also remember the 5 IJN mothersubmarines that lay in wait in Mamala Bay for just such one-by-one or single file exits.
* US Navy divers have their 20,000 hours logged under water with zero visibility increased by a small amount. Since you seem to disagree just what clearance time estimates (and sources for) do you offer wrt to the Tatuta Maru block ? IIRC there were only 18 trained/qualified US hardhat divers stationed on Oahu on Dec.7'41 and all of them were ordered by Kimmel to begin rescuing survivors trapped inside of sunken US warships. Its going to be a few days before TM clearance diving work can even begin.
*The channel is cleared long before the damaged battleships are ready to be moved to repair facilities. Reading the entire thread will remind you that I propose the destruction by burning of the US reserve fuel suply and the bombardment of the trapped US battleships by IJN battleship bombardment. The drydocks too. I'll be more than just a few days/weeks before any US warships inside of PH are going to move anywhere.
 
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