One of the main reasons given for Japan taking the road to war is Oil. Now knowing this full well why didn't the USN submarines go after the Japanesse tanker fleet from the outset.
In December 1941 the Japanesse tanker fleet had some 575,464 worth of tonnage, which increased year on year, and it was not till April 1945 that it went below the December 41 level.
Surely a concentrated effort against Japanesse oil tankers would have brought huge beneficial results by the end of 1943 at the latest. For some reason the USN put tankers fourth on there list of targets for their submarines-Why?
Tis isn't in anyway meant to detract from the heroic service given by the US subs in the Pacific, but a question in trying to understand how such an opportunity was missed.
Andy H
USA's missed opportunity?
-
ChristopherPerrien
- Member
- Posts: 7051
- Joined: 26 Dec 2002, 01:58
- Location: Mississippi
Could you list the all of the targeting priorities list, and any extra info connected with that list. There are all kinds of issues involved in a targeting priority list.Surely a concentrated effort against Japanesse oil tankers would have brought huge beneficial results by the end of 1943 at the latest. For some reason the USN put tankers fourth on there list of targets for their submarines-Why?
-
ChristopherPerrien
- Member
- Posts: 7051
- Joined: 26 Dec 2002, 01:58
- Location: Mississippi
Exactly Andy.
It is impossible to judge if this is an error in "strategic" priorities with just this statement. I gather the author(s) you are looking at are trying to prove some personal theory by not publishing the rest or maybe they don't realize the what or the why a target priority list is set up. Second guessing seems to be favorite "past-time" of some authors. Actually I have noticed even good authors sometimes insert these kind of" matter of fact", "blurbs" in otherwise good work. You don't really notice them unless you go back with a critical eye and notice this kind of stuff. Editors miss them becasuse they know less than the authors. Hell I have evn seen John Keegan insert some stupid "blurbs" in his work. Wish I could rembers enough to give you a page example. Perhaps when I re-read some book I got a will start a topic on " When good historians say dumb things".
Given the nature of the Japanese shipping tactics, i.e. no convoys , American subs most the the time operated on a simpler set of rules: sink
what they found on sight, as long as it was worth a torpedo, if not use gunfire, without getting themselves destroyed in either case. So American submariners very rarely would have to make a decision as to what to sink first.
Tankers could well have been forth for several reasons. As you said
aircraft carriers would be a higher priority, I think so would "Troop Transports", even a supply or ammo ship would be more immediately damaging to the Japanese war effort. So there are the first three? I see no problem with tankers forth on that list if that is what it is.
We really can't tell without knowing more about the tactical and strategic aspects of this list. And it seems the authors did this on purpose or out of
ignorance or error. Perhaps they just transposed a listing borrowed from the bombing campaign against Germany that had "OIL" as a forth on the strategic target list?????!!!!!!!!
Regards,
Chris
It is impossible to judge if this is an error in "strategic" priorities with just this statement. I gather the author(s) you are looking at are trying to prove some personal theory by not publishing the rest or maybe they don't realize the what or the why a target priority list is set up. Second guessing seems to be favorite "past-time" of some authors. Actually I have noticed even good authors sometimes insert these kind of" matter of fact", "blurbs" in otherwise good work. You don't really notice them unless you go back with a critical eye and notice this kind of stuff. Editors miss them becasuse they know less than the authors. Hell I have evn seen John Keegan insert some stupid "blurbs" in his work. Wish I could rembers enough to give you a page example. Perhaps when I re-read some book I got a will start a topic on " When good historians say dumb things".
Given the nature of the Japanese shipping tactics, i.e. no convoys , American subs most the the time operated on a simpler set of rules: sink
what they found on sight, as long as it was worth a torpedo, if not use gunfire, without getting themselves destroyed in either case. So American submariners very rarely would have to make a decision as to what to sink first.
Tankers could well have been forth for several reasons. As you said
aircraft carriers would be a higher priority, I think so would "Troop Transports", even a supply or ammo ship would be more immediately damaging to the Japanese war effort. So there are the first three? I see no problem with tankers forth on that list if that is what it is.
We really can't tell without knowing more about the tactical and strategic aspects of this list. And it seems the authors did this on purpose or out of
ignorance or error. Perhaps they just transposed a listing borrowed from the bombing campaign against Germany that had "OIL" as a forth on the strategic target list?????!!!!!!!!
Regards,
Chris
As of June 24, 1943 target priority list was:
1. Aircraft Carriers
2. Battleships
3. Auxiliary Carriers
4. Oil Tanker
5. any Man-of-War larger than a destroyer
6. Transport
7. Freighter
8. Destroyer
As you can see, the first three are much more important than an oil tanker. However, an American submarine could be expected to mostly encounter the bottom three ( 6 - 8 ).
You must also remember, the torpedo problem was not finally solved until the end of 43-beginning of 44. Even though US Submariners worked out ways around this problem, it still led to many missed shots.
Another factor was that there were too few submarines to fully blockade Japan. Submarines could not maintain constant patrols in all the areas necessary to cut Japan's shipping down to size. I believe this was still a problem until late 1943-early 1944.
As the Japanese did not fully institute a convoy system until 1943. They relied mostly on single ship sailings(although in 1942 small convoys were begun). So it was mostly due to luck and chance that an oiler, or any ship for that matter, crossed paths with a submarine.
Lets not forget that Japan was also building ships too. She really ramped up production of and conversion to tankers. Tanker tonnage began to drop in 1944, but new construction/conversion was able to make up the difference and even increase tanker tonnage.
1. Aircraft Carriers
2. Battleships
3. Auxiliary Carriers
4. Oil Tanker
5. any Man-of-War larger than a destroyer
6. Transport
7. Freighter
8. Destroyer
As you can see, the first three are much more important than an oil tanker. However, an American submarine could be expected to mostly encounter the bottom three ( 6 - 8 ).
You must also remember, the torpedo problem was not finally solved until the end of 43-beginning of 44. Even though US Submariners worked out ways around this problem, it still led to many missed shots.
Another factor was that there were too few submarines to fully blockade Japan. Submarines could not maintain constant patrols in all the areas necessary to cut Japan's shipping down to size. I believe this was still a problem until late 1943-early 1944.
As the Japanese did not fully institute a convoy system until 1943. They relied mostly on single ship sailings(although in 1942 small convoys were begun). So it was mostly due to luck and chance that an oiler, or any ship for that matter, crossed paths with a submarine.
Lets not forget that Japan was also building ships too. She really ramped up production of and conversion to tankers. Tanker tonnage began to drop in 1944, but new construction/conversion was able to make up the difference and even increase tanker tonnage.
Last edited by Takao on 26 Oct 2003, 19:48, edited 1 time in total.
Hi Chris
I agree that most authors have some agenda, but this info comes from the West Point Military Series by General Thomas E Greiss and that this particular deals with the Pacific war.
Hi Takao
Thanks for providing the list.
I'm not surprised to see A/C's as the main target, though I would have thought that Battleships (Given that there star was on the wain, bar for the prestige of sinking one) wouldn't be such a priority.
BTW Does anyone know how many capital ships the US Sub force sank in WW?
Though the Japanesse had no particular convoy system the whereabouts of the main oil facilities was well known to the USN, so it wouldn't have been that hard to monitor these places and task assets accordingly.
Hi Tiornu
I agree that the strategy worked, but if they had pushed the Tankers higher up the list, the strategy may well have been proven earlier, given that the IJN couldn't sail due to sparse fuel reserves.
Andy H
I agree that most authors have some agenda, but this info comes from the West Point Military Series by General Thomas E Greiss and that this particular deals with the Pacific war.
Hi Takao
Thanks for providing the list.
I'm not surprised to see A/C's as the main target, though I would have thought that Battleships (Given that there star was on the wain, bar for the prestige of sinking one) wouldn't be such a priority.
BTW Does anyone know how many capital ships the US Sub force sank in WW?
Though the Japanesse had no particular convoy system the whereabouts of the main oil facilities was well known to the USN, so it wouldn't have been that hard to monitor these places and task assets accordingly.
Hi Tiornu
I agree that the strategy worked, but if they had pushed the Tankers higher up the list, the strategy may well have been proven earlier, given that the IJN couldn't sail due to sparse fuel reserves.
Andy H
substuff
I don't think it made any difference where the tankers were prioritised vis-a-vis carriers. I'm fairly certain no submarine commander ever said, "I have this tanker here I can attack, or I can wait and hope a carrier happens along. Aaaah...I'll let the tanker go." And there were no situations that I know of in which a submarine had simultaneous opportunities to hit a carrier and a tanker.
If I am wrong, and there were a couple such situations, even then I'd say the priorities were correct. The loss of a single carrier was much more telling than the loss of a single tanker.
Only one Japanese battleship was sunk by an American sub: Kongo, late in the war. Japanese carriers sunk by subs include Taiho, Shokaku, Shinyo, Taiyo, Unyo, Chuyo, Unryu, and of course Shinano.
If I am wrong, and there were a couple such situations, even then I'd say the priorities were correct. The loss of a single carrier was much more telling than the loss of a single tanker.
Only one Japanese battleship was sunk by an American sub: Kongo, late in the war. Japanese carriers sunk by subs include Taiho, Shokaku, Shinyo, Taiyo, Unyo, Chuyo, Unryu, and of course Shinano.
sub
Hmm. The significance of the tanker fleet to the IJN was that the tankers allowed movement to the IJN. The significance of warships to the IJN was that the IJN did not exist apart from them. Which would be more useless, a paralyzed body or no body at all? Hard to answer that.
It may all be moot anyway. If you look at the above list of capital ships, you may note that only one of the losses took place prior to June 1944 (Chuyo Dec 1943). So a change of priorities would not likely have effected a crisis by the end of 1943. There were a few other sub attacks prior to the successes in the list, but not enough to worry about.
The change that was needed was in the US torpedo design, plus a tweaking of the submarine CO corps for increased aggressiveness.
It may all be moot anyway. If you look at the above list of capital ships, you may note that only one of the losses took place prior to June 1944 (Chuyo Dec 1943). So a change of priorities would not likely have effected a crisis by the end of 1943. There were a few other sub attacks prior to the successes in the list, but not enough to worry about.
The change that was needed was in the US torpedo design, plus a tweaking of the submarine CO corps for increased aggressiveness.
No offense Andy, But a General writing a paper on submarine warfare makes about as much sense as an Admiral writing one on infantry tactics.
Each one may know the basic premise and grasp obvious concepts, However, these points are but the tip of the iceberg.
At the start of the war, in 1941, the Japanese Navy had enough oil reserves to fight for two years. So even shutting the spigot off then, the war would continue until the beginning of 1944. Now, given that US submarine arm did not start becoming effective until 1943(in terms of monthly tonnage sunk), this gave Japan a little more breathing room, but not much.
Not only that, but if The US had clustered it submarines at given ports, this probably would have forced the Japanese to come to grips with the problem much sooner than 1943. For example, if we take the obvious conclusion: stationing US subs off Japan's major oil ports. Can we not make the same simple conclusion that the Japanese will in turn start stationing more destroyers, ASW ships, and aircraft around these given ports. Thereby negating what we were trying to achieve in the first place. The submarine's major benefits are stealth and surprise. By placing them in or near a given port, they are restricted to a small and shallow area of sea. This negates stealth, by confining to a shallow area, the sub easier to spot by aircraft and cannot dive deep to evade an ASW vessel. By restricting the sub to given ports, surprise is negated and the enemy knows where the submarine will generally be located. The submarines were much better off using the strategies and tactics they did. By prowling the known shipping lanes where they were free to manuever and striking at ships they crossed pathes with. That way, they were freed from becoming easy targets for Japan's ASW forces.
Now, being that Japan is an island nation, she must survive by importing most of her raw materials. Now, if the war was to be won, all materials coming into Japan must be eliminated, not just oil. In 1940, Japan was importing some 22 million tons of raw materials. By 1943, this had dropped to 16.5 miilion tons and by 1945 Japan imported only 2.5 million tons. This is what the submarineshad to do; stop all ships, not just oil tankers, but all ships. Thereby strangling Japan, unfortunately the numbers of submarines to do the job just was not there until 1943-44.
I think we all agree the the priority list was for multiple contacts, and not just single targets. I think the General has failed to grasp this concept.
The only situation that I can remember where it came down to a carrier or a tanker, was the USS Barb vs. IJN Unyo & Azusa. The Barb, under Commander Eugene Fluckey, came upon a five ship convoy. Fluckey ID'd the tanker first, and while making his approach ID'd the carrier Unyo.
Fluckey adjusted his course so as to achieve an overlap of the two targets. The Barb fired her 6 forward tubes at the two and was in the process of a hard turn to fire the 4 stern tubes when an escort forced her deep. 3 torpedoes hit the Unyo and two hit the oiler, both sank.
If anyone wants some good book on US Submarine warfare, I reccomend
"United States Submarine Operations In World War II", by Theodore Roscoe (also published in paperback by the title "Pigboats"
"Silent Victory" by Clay Blair Jr.
Each one may know the basic premise and grasp obvious concepts, However, these points are but the tip of the iceberg.
At the start of the war, in 1941, the Japanese Navy had enough oil reserves to fight for two years. So even shutting the spigot off then, the war would continue until the beginning of 1944. Now, given that US submarine arm did not start becoming effective until 1943(in terms of monthly tonnage sunk), this gave Japan a little more breathing room, but not much.
Not only that, but if The US had clustered it submarines at given ports, this probably would have forced the Japanese to come to grips with the problem much sooner than 1943. For example, if we take the obvious conclusion: stationing US subs off Japan's major oil ports. Can we not make the same simple conclusion that the Japanese will in turn start stationing more destroyers, ASW ships, and aircraft around these given ports. Thereby negating what we were trying to achieve in the first place. The submarine's major benefits are stealth and surprise. By placing them in or near a given port, they are restricted to a small and shallow area of sea. This negates stealth, by confining to a shallow area, the sub easier to spot by aircraft and cannot dive deep to evade an ASW vessel. By restricting the sub to given ports, surprise is negated and the enemy knows where the submarine will generally be located. The submarines were much better off using the strategies and tactics they did. By prowling the known shipping lanes where they were free to manuever and striking at ships they crossed pathes with. That way, they were freed from becoming easy targets for Japan's ASW forces.
Now, being that Japan is an island nation, she must survive by importing most of her raw materials. Now, if the war was to be won, all materials coming into Japan must be eliminated, not just oil. In 1940, Japan was importing some 22 million tons of raw materials. By 1943, this had dropped to 16.5 miilion tons and by 1945 Japan imported only 2.5 million tons. This is what the submarineshad to do; stop all ships, not just oil tankers, but all ships. Thereby strangling Japan, unfortunately the numbers of submarines to do the job just was not there until 1943-44.
I think we all agree the the priority list was for multiple contacts, and not just single targets. I think the General has failed to grasp this concept.
The only situation that I can remember where it came down to a carrier or a tanker, was the USS Barb vs. IJN Unyo & Azusa. The Barb, under Commander Eugene Fluckey, came upon a five ship convoy. Fluckey ID'd the tanker first, and while making his approach ID'd the carrier Unyo.
Fluckey adjusted his course so as to achieve an overlap of the two targets. The Barb fired her 6 forward tubes at the two and was in the process of a hard turn to fire the 4 stern tubes when an escort forced her deep. 3 torpedoes hit the Unyo and two hit the oiler, both sank.
If anyone wants some good book on US Submarine warfare, I reccomend
"United States Submarine Operations In World War II", by Theodore Roscoe (also published in paperback by the title "Pigboats"
"Silent Victory" by Clay Blair Jr.
Hi TakaoNo offense Andy, But a General writing a paper on submarine warfare makes about as much sense as an Admiral writing one on infantry tactics.
Each one may know the basic premise and grasp obvious concepts, However, these points are but the tip of the iceberg.
Certainly no offense taken on my part. What I should have mentioned that this guy is also a Professor and Head of the History Departmet at West Point, and looking at the acknowledgements he did also have some naval input.
I take your point about having 2yrs reserves in hand but there's knowing you have 2yrs reserves in hand and more coming, or having 2yrs reserves and know that nothing is coming because you have no means of transporting it.
Regarding as I proposed, lying subs off oil terminals etc, I again think you make some valid points, but Japanesse ASW assets were woeful and they had hardly any infrastructure to enlarge this area of technical warfare. Also the allies would know what the likely "convoy" routes would be and could attack at any point along it. This would force more IJN escorts away from other duties and also use up valuable fuel oil etc.
Andy H
-
Simon Gunson
- Member
- Posts: 784
- Joined: 23 Mar 2004, 01:25
- Location: Wellington, New Zealand
USA's missed opportunity?
Dear Andy
In a sense they did concentrate on tankers, because from 1943 the US subs in the South China Sea started using German wolfpack tactics.
Until they had the numbers on station they could not straddle the shipping lanes. By using wolfpacks on shipping lanes they pretty quickly did deny oil shipments by late 44.
Remember too that the US far east sub fleet did not reach it's Freemantle base until mid 1942.
If you read "Japanese Aircraft of the Pacific War" 1970 - reprint 1988, by Rene J Francillon ISBN 0-87021-313X you will find at the back reference to the Ohtori or phoenix transport plane. The Japanese were pushed into flying oil by late in the war. It was so inefficient that 80% of the oil cargo on each flight was used on the flight itself !
The odd thing for me is why the Japanese did not use Zepplin L.37 which was provided to Japan as First World War reparations in August 1920 for hauling oil ?
In a sense they did concentrate on tankers, because from 1943 the US subs in the South China Sea started using German wolfpack tactics.
Until they had the numbers on station they could not straddle the shipping lanes. By using wolfpacks on shipping lanes they pretty quickly did deny oil shipments by late 44.
Remember too that the US far east sub fleet did not reach it's Freemantle base until mid 1942.
If you read "Japanese Aircraft of the Pacific War" 1970 - reprint 1988, by Rene J Francillon ISBN 0-87021-313X you will find at the back reference to the Ohtori or phoenix transport plane. The Japanese were pushed into flying oil by late in the war. It was so inefficient that 80% of the oil cargo on each flight was used on the flight itself !
The odd thing for me is why the Japanese did not use Zepplin L.37 which was provided to Japan as First World War reparations in August 1920 for hauling oil ?
-
Delta Tank
- Member
- Posts: 2513
- Joined: 16 Aug 2004, 02:51
- Location: Pennsylvania
I believe that the target priority list changed from time to time during the war. If I remember correctly in Admiral Lockwood's book "Sink Them All" or something like that. He stated that the priority at one time was destroyers and at another time it was oil tankers. I will have to find the book in my library.
I think that there were two submarine commands in World War II in the Pacific area. One was at Pearl Harbor under Lockwood and the other was at Freemantle (?) Australia. They may of had different priority target lists.
Mike
It has been 20 years since I read this book.
I think that there were two submarine commands in World War II in the Pacific area. One was at Pearl Harbor under Lockwood and the other was at Freemantle (?) Australia. They may of had different priority target lists.
Mike
It has been 20 years since I read this book.
-
Delta Tank
- Member
- Posts: 2513
- Joined: 16 Aug 2004, 02:51
- Location: Pennsylvania