robdab
06-18-2008, 09:16 PM
Things seem to be slowing down on the other threads that I enjoy so I'd thought that I'd try yet another "what if" scenario ? With your permission I'd like to ...
1.) ... leave aside the entire "Japanese strategic doctrine would never have allowed that" discussion/debate and just assume that somehow/someway, it was so ordered. Maybe Emperor Hirohito had a dream ...
2.) Likewise, I'd like to sidestep the entire "the IJN didn't have the logistics base to support a move by the Combined Fleet to Oahu" discussion/debate. I know and accept that already but would like to have a bombardment discussion and so have assumed that the fuel/supplies/ammo would be provided, somehow/somewhere, like manna from heaven. Aren't AHs just grand at sidestepping the details ...
Actually, my pet theory is that Japan might have used many of the high speed modern tankers idled by the American led oil embargo against her, to re-fuel the Combined Fleet as it headed east. Historically they did so convert, to underway re-fueling status, some of those tankers otherwise anchored in the Inland Sea. In effect, creating more last minute and poorly trained fleet oilers, in great secrecy. Since they did it historically, I don't think it too much of a "mental stretch" to assume that 3.) they could have so converted more in the time that they had available. With the a similar degree of success and secrecy.
So, the Combined Fleet, less the two battlecruisers historically sent south in support of the Southern Operation, crosses the Pacific behind the Kido Butai, having also left it's usual radio operators back in Japan to transmit fake messages from there.
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Pre-mission scouting on Oahu by Yoshikawa would have revealed that the map found at http://militarymaps.org.ua/maps/osprey/fort_008/map9.djvu is far too optomistic for Dec.'41. (You'll need the Djvu viewer which is available for free download at djvu.com to see that map)
First, you'll have to erase all of the black firing arcs because those batteries were built after Dec.7'41. Next go the browns for a similar reason. Finally the purple #6 arc gets converted to a 360 degree circle to more properly show its real 16" firing arc on Dec.7'41. The existing purple arc shows it's casemated firing arc after it was fortified circa late 1942.
Not nearly so impressive a defensive map of US 8" and larger firepower now, is it ?
I note that it does not show any of the 4x4x8" railway gun batteries then on Oahu because they each took at least two days to get into firing position on their pre-built strengthened sidings and were NOT so emplaced on Dec.7'41.
Also missing are eight US Army 240mm semi-mobile howitzers, for a similar reason. Two days to deploy onto pre-poured circular cement bases and they were all "in the barn" on the mornming of Dec.7'41. Their crews were not trained/equipped for anti-shipping fire in any case. Their mission was anti-invasion beach defense, firing to the pre-registered waterline only.
The map does not show the short 360 degree firing arcs of the the 155mm towed howitzers either since the US troops did not customarily leave them out on their "panama mount" concrete bases, untended, when they returned to their barracks for the weekend.
The US Army on Hawaii was equipped with many more smaller artillery pieces also but I have ignored these as being too small to pose a treat to an IJN armoured battleship. They too were parked in their armories buildings for the weekend and their crews were trained for ground combat support, not anti-shipping fire.
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Having viewed the US coastal artillery defences and their range arcs, please now go to http://militarymaps.org.ua/maps/osprey/062_pearl_harbor/map03.djvu to view the potential IJN bombardment targets on Oahu. This map also shows the historical air attacks which would be much modified in the event of expected IJN Combined Fleet battleship (and heavy cruiser) participation.
Potential targets missing from that map are Fort Shafter which is located just south of the "NAS" of the "Pearl Harbor NAS" label, the John Rogers International Airport located just to the right of the "d" in the Hickam Field" label and the oil tankfarms located at the "E" below the "Pearl Harbor NAS" label. Several more including the Aliamanu Crater Ammunition Depot, the Luailuai radio transmission towers and Fort Ruger located inside Diamond Head Crater could also be added to the targeting list. There is NO shortage of American tarets to blow up on Dec.7'41.
------------------------------------------------------------------------
Have I overlooked anything ? Are you interested ? Let me know.
1.) ... leave aside the entire "Japanese strategic doctrine would never have allowed that" discussion/debate and just assume that somehow/someway, it was so ordered. Maybe Emperor Hirohito had a dream ...
2.) Likewise, I'd like to sidestep the entire "the IJN didn't have the logistics base to support a move by the Combined Fleet to Oahu" discussion/debate. I know and accept that already but would like to have a bombardment discussion and so have assumed that the fuel/supplies/ammo would be provided, somehow/somewhere, like manna from heaven. Aren't AHs just grand at sidestepping the details ...
Actually, my pet theory is that Japan might have used many of the high speed modern tankers idled by the American led oil embargo against her, to re-fuel the Combined Fleet as it headed east. Historically they did so convert, to underway re-fueling status, some of those tankers otherwise anchored in the Inland Sea. In effect, creating more last minute and poorly trained fleet oilers, in great secrecy. Since they did it historically, I don't think it too much of a "mental stretch" to assume that 3.) they could have so converted more in the time that they had available. With the a similar degree of success and secrecy.
So, the Combined Fleet, less the two battlecruisers historically sent south in support of the Southern Operation, crosses the Pacific behind the Kido Butai, having also left it's usual radio operators back in Japan to transmit fake messages from there.
--------------------------------------------------------------------------------
Pre-mission scouting on Oahu by Yoshikawa would have revealed that the map found at http://militarymaps.org.ua/maps/osprey/fort_008/map9.djvu is far too optomistic for Dec.'41. (You'll need the Djvu viewer which is available for free download at djvu.com to see that map)
First, you'll have to erase all of the black firing arcs because those batteries were built after Dec.7'41. Next go the browns for a similar reason. Finally the purple #6 arc gets converted to a 360 degree circle to more properly show its real 16" firing arc on Dec.7'41. The existing purple arc shows it's casemated firing arc after it was fortified circa late 1942.
Not nearly so impressive a defensive map of US 8" and larger firepower now, is it ?
I note that it does not show any of the 4x4x8" railway gun batteries then on Oahu because they each took at least two days to get into firing position on their pre-built strengthened sidings and were NOT so emplaced on Dec.7'41.
Also missing are eight US Army 240mm semi-mobile howitzers, for a similar reason. Two days to deploy onto pre-poured circular cement bases and they were all "in the barn" on the mornming of Dec.7'41. Their crews were not trained/equipped for anti-shipping fire in any case. Their mission was anti-invasion beach defense, firing to the pre-registered waterline only.
The map does not show the short 360 degree firing arcs of the the 155mm towed howitzers either since the US troops did not customarily leave them out on their "panama mount" concrete bases, untended, when they returned to their barracks for the weekend.
The US Army on Hawaii was equipped with many more smaller artillery pieces also but I have ignored these as being too small to pose a treat to an IJN armoured battleship. They too were parked in their armories buildings for the weekend and their crews were trained for ground combat support, not anti-shipping fire.
-----------------------------------------------------------------
Having viewed the US coastal artillery defences and their range arcs, please now go to http://militarymaps.org.ua/maps/osprey/062_pearl_harbor/map03.djvu to view the potential IJN bombardment targets on Oahu. This map also shows the historical air attacks which would be much modified in the event of expected IJN Combined Fleet battleship (and heavy cruiser) participation.
Potential targets missing from that map are Fort Shafter which is located just south of the "NAS" of the "Pearl Harbor NAS" label, the John Rogers International Airport located just to the right of the "d" in the Hickam Field" label and the oil tankfarms located at the "E" below the "Pearl Harbor NAS" label. Several more including the Aliamanu Crater Ammunition Depot, the Luailuai radio transmission towers and Fort Ruger located inside Diamond Head Crater could also be added to the targeting list. There is NO shortage of American tarets to blow up on Dec.7'41.
------------------------------------------------------------------------
Have I overlooked anything ? Are you interested ? Let me know.