Who Sank The Most Tonnage?

[Mark V]

Indeed, the routes from Asia to Japan bring raw materials and food to Japan are much shorter than those across the Atlantic thus significantly reducing the room that shipping had to hide in.

Not forgetting the plentitude of traffic choke-points:

- Strait of Malacca
- Formosa Strait
- Luzon Strait
- Strait of Korea
- approaches to Inland Sea

.... just to name few of them.

Mark V

[Caldric]

The point is even if there were choke points, which can be said about the Atlantic also. The Subs had to sail further and then remain on station at great distances. The Pacific and Atlantic were two different war zones.

To say the Germans were better because they lost 3/4 of its sub fleet is not a very good measuring stick. Success is in the fact that Japan had no ships left at the end of the war.

[ChristopherPerrien]

The German U-boats sunk more allied ship becuase their were more allied ships to sink. And yes I believ they sunk the Allied prewar-merchant fleet size a couple times by wars end , but at the end of the War the Alllied merchant Marine was much bigger than it started and the percentage of ships sunk to total Allied tonnage is much less than the 70% or so of Japanese merchant ships sunk by the US fleet.

I don't think we can really talk scale as to who was best , I tyhink the most accurate way would be to find an average based on tonnage sunk divided by total number of submarines.

As to losse the U-boats took a beating but the US submarine force, I think also lost more than half of its people too , obviously it was a hazardous job no matter what side you were on.

And lets not forget the British sub fleet which sunk alot of vessels in the
Mediterranean during the war.

I think the Japanese had the largest sub fleet, but they mismanaged it so bad both tactically and strategically it never had an effect.

[ChristopherPerrien]

The German U-boats sunk more allied ship becuase their were more allied ships to sink. And yes I believ they sunk the Allied prewar-merchant fleet size a couple times by wars end , but at the end of the War the Alllied merchant Marine was much bigger than it started and the percentage of ships sunk to total Allied tonnage is much less than the 70% or so of Japanese merchant ships sunk by the US fleet.

I don't think we can really talk scale as to who was best , I tyhink the most accurate way would be to find an average based on tonnage sunk divided by total number of submarines.

As to losses the U-boats took a beating but the US submarine force, I think also lost more than half of its peoples too , obviously it was a hazardous job no matter what side you were on.

And lets not forget the British sub fleet which sunk alot of vessels in the
Mediterranean during the war.

I think the Japanese had the largest sub fleet, but they mismanaged it so bad both tactically and strategically it never had an effect.

[Hop]

And yes I believ they sunk the Allied prewar-merchant fleet size a couple times by wars end ,

I think the British fleet was something over 15,000,000 tons at the begining of the war, excluding small ships of 1,600 tons or less.

[Darrin]

The German U-boats sunk more allied ship becuase their were more allied ships to sink. And yes I believ they sunk the Allied prewar-merchant fleet size a couple times by wars end , but at the end of the War the Alllied merchant Marine was much bigger than it started and the percentage of ships sunk to total Allied tonnage is much less than the 70% or so of Japanese merchant ships sunk by the US fleet.

By mid 41 the ger were sinking CW merchant ships at almost double the rate they could be replaced using constrction from both the US and CW. Of course that assumes the pacifc stays as quiet as a wisker which it didn't. I suspect it wasn't until mid 43 that the numbers game started to incrase to almost pre war levels. It was also about this time the CW could run convoys through the med again decresing the number of ships required to keep itself running.

Much of the fleet was taken up carring food and material around. Thier were also many ineff due to the wartime convoy sytems as well. It really wasn't until the end of 43 that a real invasion could take place. It might take 15 liberty ships or 150,000 tons of cargo to bring in 1 US inf divs even more for combat support units (TD arty etc), then supply and replace them each month in combat. The biggest part was placing the div after that supply dropped to a 300 tons a month. It's the replaments that might add up but again inf less so but arm more...

By the 1 sep 44 the allies had at least 50 div in france in the north and south including french units. At least 10 of these units were arm div which would require more tonnage period I would think just as the ger pz divs did. That probably means a total of 10 mil tons and 1000 liberty ships-voyages. That seems like an awful lot esp considering that this all happened during LESS than a 3 month window. A window most ships would be unable to make a return journy to the US to make a second run. This was somewhat helped by the fact the allies could bring in supplies units etc from closer a field in the med and england. Alowing some ships to make at least 2 trips.

Even as it was thier was no extra room in 44 they needed all the spare ships they had in mid 44 for the invasion.

[Tiornu]

ChristopherPerrien, how did you come to the conclusion that the Japanese had the largest sub fleet?

[Darrin]

The German U-boats sunk more allied ship becuase their were more allied ships to sink.

I think the Japanese had the largest sub fleet, but they mismanaged it so bad both tactically and strategically it never had an effect.

The largest merchant fleets at the begining of the war by far were the US and Cw. Both of these forces were conc very heavily in the atlantic making it target rich for the ger subs.

It was hard for the japs subs to find any of the allied merchant shiping in the pacific as it hugged the west coast primarly and was quite out of range of thier ships. The eastern part of the pacific is very port and island poor. The jap would have had a hard time even developing a susful anti merchant ship phiolsophy if they wanted.

On the other hand ther were a huge number of island and port in the western pacifc area. The allies just had to hold on to or size one to operate ther subs from. The jap merchant fleet was small but it was still the third largest in the world and was conc from the NEI to its home waters making finding it reality easily. Esp with sup number of coast watchers, recon aircraft, and decoding etc...

[Tiornu]

"It was hard for the japs subs to find any of the allied merchant shiping in the pacific as it hugged the west coast primarly and was quite out of range of thier ships."
This needs some correction. The Japanese had numerous classes with cruising ranges of 14,000nm or more, several with 20,000nm or more. I-Boats did more than shell and bomb the US West Coast; they also attacked shipping there, but not with any resolve.
There's also the matter of the extended LoC in the Pacific, reaching to Pearl Harbor and west from there. The Japanese had plenty of merchant targets to pursue if they'd wanted.

[ChristopherPerrien]

ChristopherPerrien, how did you come to the conclusion that the Japanese had the largest sub fleet?

I think they did at the start( i.e.pre-war) in 1941. More than the US, not sure about Germany who started a little earlier, in the Battle of the Atlantic with 57 U-boats.

I can find the numbers for 1940-41 at the moment. Maybe you can

[DrG]

According to this article ( http://www.ahoy.tk-jk.net/Underwater/30 ... neFle.html; I think it's very interesting, except for the part about Italy, because the author had little or no info about it):

Japan started the war with 63 operational Boats, 48 I Class, or large Submarines, and 15 of the smaller RO Class, and they had another 29 Boats under construction, but not yet completed.

In all, 126 Submarines were built during the war, and 56 remained at the surrender. Most were inoperable through lack of maintenance or damage sustained at sea. 127* Japanese Submarines ( excluding Midgets ) were lost in the Pacific War- 70 to Ships, 19 to enemy Submarines, 18 to Aircraft, and the balance to miscellaneous causes.

[Mark V]

I can find the numbers for 1940-41 at the moment. Maybe you can

Italy and USSR both had larger submarine fleet in 1940 than any of the earlierly mentioned naval powers.

Mark V

[cuski]

The point is even if there were choke points, which can be said about the Atlantic also. The Subs had to sail further and then remain on station at great distances. The Pacific and Atlantic were two different war zones.

To say the Germans were better because they lost 3/4 of its sub fleet is not a very good measuring stick. Success is in the fact that Japan had no ships left at the end of the war.

The Japanese purpose-built escorts in 1941 were deemed ill-provided for escort-duties. They only carried 18 depth charges, and had absolutely no underwater detection systems until autumn 1942 when they fitted hydrophones (at a time when 2100 british ships were already equipped with asdic/sonar).

"The Imperial Navy lacked any ahead-throwing weapon system and its depth charges were wholly inadequate in terms of weight of explosive and rate of sinking. The Imperial Navy had no influence mines or any form of airborne anti-submarine weapon other than the bomb. Moreover, it was not until autumn 1944 that Japanese escorts were equipped with the Type 13 search radar, and Japanese escorts were equipped with only one radio transmitter that had to work on both high and low frequencies despite the fact that escorts were often required to wok on both simultaneously." ("The Second World War in The Far East", H. P. Willmott, p. 77)

In December 1941, the Japanese Navy had only 49 tankers of 587,000 tons. By way of comparison, in 1939 Britain had 425 tankers of 2,997,000 and the US had 389 tankers of 2,836,000 tons. (same book, p. 76)

Not under any circumstance, the fact that the Japanese had no ships left at the end is a good measuring stick, IMO.

[ChristopherPerrien]

I will correct a few of my earlier errors, the Japanese had more subs than the US had in the pacific at the start of the war. 63 to 51, the Us had a total of 111 boats. Like I said the Germans had 57 to start probably many more by 1941.

US submariners took 28% casualties whereas German U -boats took more than 60%

I forgot, granted they are hardly worth mentioning, about the USSR and Italy subs fleets, as they did much less than even the Japanese with their subs.

Not under any circumstance, the fact that the Japanese had no ships left at the end is a good measuring stick, IMO.

Why? Sinking stuff till there is nothing left to sink seems like a fair measure of a submarine force's effectiveness. "In Mush we Trust!"

[Caldric]

Not under any circumstance, the fact that the Japanese had no ships left at the end is a good measuring stick, IMO.

I would suggest you read on Adm. Donitz then, for he said it was the exact measurement for a successful submarine warfare campaign. I wish I had the quote, but he stated the US succeeded where Germany failed.