Mk-48 Torpedo Results

[TorpX]

Yes, at $3.8M it is expensive, but it is a +90% sure kill; Mark 14s were expected to be launch in salvos and a 10% success rate more than acceptable...

How does torpedoing a small, uncrewed, ship at anchor prove a weapon is capable of giving 90% sure kills in battle? This sort of test strikes me as being no more serious than those done with the Mk 14's and others before WWII.

They did test the Mk.14 but with the magnetic detonator they did not test a live round and it was off the east coast the reason they did so little testing was because they wanted to keep it secret (this was in the late 30s) the problem with the mk.14 was that it went through a very limited and unrealistic testing program.Once they ran tests in Fremantle and Hawaii the submariners solved the mk.14s problems without the help of engineers.

In 1926, they did two live tests with a Magnetic Influence exploder. In the first one, the torp ran under the target without exploding, it being considered to have run too deep. When the torpedo was adjusted and fired again, it exploded under and sank the target (an obsolete sub). It should be noted that these were not production Mk 14's and Mk 6 exploders, but rather prototypes that were modified later, so these were not really "battlefield" tests of frontline weapons. Nevertheless, they were impressive enough to be considered a success.

I believe the main reason for such skimpy testing was the expense, not secrecy. Not only were the torpedos themselves very expensive, but suitable "targets" were nearly impossible to obtain. Further testing was done with test warheads, using "electric eyes" and recording devices and the like.

IMO, proving the effectiveness of the MI exploder would be almost impossible without blowing up a large number of ships. The Navy would have been much better off to focus on impact detonation, which could be tested and didn't have all the messy unknowns of MI. Verification of running depth was easily done with net shots, and testing of impact exploders can be done by dropping test warheads against steel plates and the designs analyzed afterwards. Impact forces can be calculated and this does not require live shots, or mapping magnetic forces around a ship, or adjusting for the earth's magnetic field.

[Roger Dodger]

Originally Posted by TorpX

IMO, proving the effectiveness of the MI exploder would be almost impossible without blowing up a large number of ships. The Navy would have been much better off to focus on impact detonation, which could be tested and didn't have all the messy unknowns of MI. Verification of running depth was easily done with net shots, and testing of impact exploders can be done by dropping test warheads against steel plates and the designs analyzed afterwards. Impact forces can be calculated and this does not require live shots, or mapping magnetic forces around a ship, or adjusting for the earth's magnetic field.

Ah, you must have seen the movie "Operation Pacific" (1951). That John Wayne is such a hero . The film is supposed to have been based on real events (except the sappy love interest ).

From IMDb:
During WWII, a submarine's second in command inherits the problem of torpedoes that don't explode. When on shore, he is eager to win back his ex-wife.

[Bilge_Rat]

To be fair, the magnetic influence exploder was the "wonder weapon" of submariners in the pre-war period and was being developped by the Kriegsmarine and the Royal Navy as well. The same concept was used in British, American and German magnetic mines. It was not all the U.S. Navy's fault since Congress had cut military budgets to the bone in the 20's (disarmament) and 30's (depression) which severely limited live testing. The Kriegsmarine which had an unlimited budget after 1933 still wound up with a malfunctioning torpedo MI in 1939.

[kstanb]

What was completely US navy's fault was to stick to this magnetic detonator for one year and a half; even after numerous reports from captains... There is a big problem when you put more trust on office bureaucrats than front line captains.

[Stealhead]

Originally Posted by kstanb

What was completely US navy's fault was to stick to this magnetic detonator for one year and a half; even after numerous reports from captains... There is a big problem when you put more trust on office bureaucrats than front line captains.

That is not necessarily true subs where getting hits and kills with Mk14s the entire war and alot of human error can occur with a torpedo attack there a numerous things that can cause a torpedo to miss that have nothing to do with the quality of the torpedo itself.They should have tested the mk.14 more this is true but it is very common for front line units to grossly over rate or underrate hardware.The other thing many forget to take into consideration was that there was another unrelated issue of the torpedoes not running at proper depth this was caused by the reduction in manufacturer quality from pre-war to wartime production and was unrelated to the magnetic detonator.Also the US Navy was fighting with subs in a manner and on a scale not tried previously there was alot of trail and error going on with submarine operations and not matter what you are always learning.Also they stuck with the magnetic detonator 0 days after the problem was verifiable they stopped using them.

[TorpX]

Originally Posted by Roger Dodger

Ah, you must have seen the movie "Operation Pacific" (1951). That John Wayne is such a hero . The film is supposed to have been based on real events (except the sappy love interest ).

From IMDb:
During WWII, a submarine's second in command inherits the problem of torpedoes that don't explode. When on shore, he is eager to win back his ex-wife.

Yeah, I did see the movie a long time ago, but I was thinking of a more "faithful" type of test. One where you had a warhead moving horizontally to impact a steel plate. (Think of a child's swing, or a ballistic pendulum.) In this way you could use any angle and check compound angles, without even getting wet. I believe it was Adm. Lockwood who ordered the drop tests done (like in the movie).

... subs where getting hits and kills with Mk14s the entire war and alot of human error can occur with a torpedo attack there a numerous things that can cause a torpedo to miss that have nothing to do with the quality of the torpedo itself...

I will agree with this up to a point, but there was a long series of failures by the USN in this matter. We know comprehensive testing was possible, since it was eventually done. Lack of funds was perhaps a valid excuse in the '30's, but not in the era when the Navy was in the midst of an ambitious submarine building program. That excuses were still being made for not doing meaningful tests, after we were at war, is almost beyond belief.

[Platapus]

Originally Posted by TorpX

I will agree with this up to a point, but there was a long series of failures by the USN in this matter. We know comprehensive testing was possible, since it was eventually done. Lack of funds was perhaps a valid excuse in the '30's, but not in the era when the Navy was in the midst of an ambitious submarine building program. That excuses were still being made for not doing meaningful tests, after we were at war, is almost beyond belief.

I think you are being a bit harsh

Remember that after the attack on Cavite , the US Navy lost a good number of torpedoes. About half in the PTO If my poor memory serves. This meant that there was a critical shortage of torpedoes in the early years of the war.

There was a choice. Fight with the weapons you have, or keep the subs berthed. During wartime the latter is not a popular decision.

There was not a lot of money or spare torpedoes for testing, even during the war. Sure with 70 years of hindsight the decision is self-evident. But when evaluating historical decisions, it is important to only evaluate them with the data that was available to the decision makers at that time.

The Mk 14 had checked out satisfactory in testing. That is a documented fact. However, as found out later, the testing process was flawed. But at the time no one knew about it.

The Mk6 exploder also checked out satisfactory in testing. But as discovered later, the testing was not a rigorous or as extensive as was needed. But no one knew that at the time.

It is very hard to diagnose errors in a system of systems when there may be multiple things wrong with it. Also, the shooting skill of early sub captains was rightfully suspect in the early years of the war.

Early war patrol reports showed that torpedoes simply missed. Who knows of those missed torpedoes ran deep, or had a faulty pistol?

Rockin Robins and others can tell us more than we ever wanted to know about how much the captains did NOT know about their targets or how to hit them.

Given only the information available at the time, and not having the advantage of 70 years of after action research, the Navy did not do all that bad. Were there political influences concerning torpedo development. Oh boy yes (Check out the book, Hellions of the deep). Where there bureaucratic fighting between BuOrd and ops. Double oh boy yes.

But there were no traitors involved, not even Capt English. Every one involved was making the best decision based on the limited data they had access to.

That is the tricky part about historical research. It is so important to segregate any and all knowledge that the people you are studying did not have. This is party of my professional job and it is tough. We lose a lot of analysts who can't segregate.

Wrong decisions were made. That is undeniable. But they are also, at the same time understandable.

[Bilge_Rat]

yes, hindsight is always 20/20.

We also have to remember that pre-war, few people seriously thought there would be a war with Japan or that the Japan would be a serious threat if there was one. Everyone was focused on Germany and the possible U-Boat threat. Pre-1939, there were also many USN/RN officers who thought subs were obsolete because of advances in sonar and depth charges. So even though there was more money for the Navy, the submarine service was still way down on the priority list. They had to fight just to get new subs built, never mind re-testing an existing weapon system.

Plus in 39-41, German successes seemed to prove the magnetic exploder worked. U-Boats were racking up impressive kills. It was known the Germans were using magnetic exploders. The British had captured and examined a German magnetic mine in 1939 and a magnetic mine had severely damaged HMS Belfast, so there was no serious reason to doubt the concept.

[Sailor Steve]

Originally Posted by Bilge_Rat

Plus in 39-41, German successes seemed to prove the magnetic exploder worked. U-Boats were racking up impressive kills. It was known the Germans were using magnetic exploders. The British had captured and examined a German magnetic mine in 1939 and a magnetic mine had severely damaged HMS Belfast, so there was no serious reason to doubt the concept.

Gotta love the difference betwee perception and reality. Everything above is true, except for the Allies having no clue of the nightmares the Germans were having with those same exploders.

[Stealhead]

Another factor to take into consideration some blame could also be laid at the feet of the SUBRON commanders they also dragged their feet a little as well they should have listened to the crews much sooner than they did and had feild tests done sooner than they did.

We also as Platapus and Bildge Rat point out have the benefit of hindsight.Also there are alot of factors not simmed in the game that give us a very opaque view.

[TorpX]

Originally Posted by Platapus

I think you are being a bit harsh

Remember that after the attack on Cavite , the US Navy lost a good number of torpedoes. About half in the PTO If my poor memory serves. This meant that there was a critical shortage of torpedoes in the early years of the war.

Yes, this is true. BuOrd used this as an excuse to avoid live testing. So, for month after month, torpedos (and opportunities) were wasted because of a defective exploder. It would have been much better to sacrifice a few torps to put the matter beyond doubt, than continue adrift, wondering why enemy ships aren't being hit.

There was a choice. Fight with the weapons you have, or keep the subs berthed. During wartime the latter is not a popular decision.

I agree keeping subs berthed would have been unacceptable. The torps could have been fixed, however. Really, there was no good reason why it couldn't have been done before the outbreak of war.

There was not a lot of money or spare torpedoes for testing, even during the war. Sure with 70 years of hindsight the decision is self-evident. But when evaluating historical decisions, it is important to only evaluate them with the data that was available to the decision makers at that time.

I agree people had to use the tools available at the time, but the notion that testing could not be done, even after the defense budget increases in the late 30's is absurd. What does it cost to build whole squardrons of state-of-the-art fleetboats?

The Mk 14 had checked out satisfactory in testing. That is a documented fact. However, as found out later, the testing process was flawed. But at the time no one knew about it.


The Mk6 exploder also checked out satisfactory in testing. But as discovered later, the testing was not a rigorous or as extensive as was needed. But no one knew that at the time.

The point is they should have known. There was almost no testing of the exploder, and little testing of depth control. Nor was such testing especially difficult; they simply chose not to do it.

It is very hard to diagnose errors in a system of systems when there may be multiple things wrong with it. Also, the shooting skill of early sub captains was rightfully suspect in the early years of the war.

All the more reason to put the matter beyond doubt with proper tests. Net shots are childishly simple, and impact testing of the exploder need not be difficult either. I'll grant you the MI feature of the Mk 6 was probably, given the tools available, impossible to adequately test. That being the case they should have made darned sure the impact mechanism worked properly.

Early war patrol reports showed that torpedoes simply missed. Who knows of those missed torpedoes ran deep, or had a faulty pistol?

Indeed. Without any real testing you can only guess.

Rockin Robins and others can tell us more than we ever wanted to know about how much the captains did NOT know about their targets or how to hit them.

Given only the information available at the time, and not having the advantage of 70 years of after action research, the Navy did not do all that bad. Were there political influences concerning torpedo development. Oh boy yes (Check out the book, Hellions of the deep). Where there bureaucratic fighting between BuOrd and ops. Double oh boy yes.

But there were no traitors involved, not even Capt English. Every one involved was making the best decision based on the limited data they had access to.

I have read the book. I don't see how anything in it excuses the failures of BuOrd or the Navy.

That is the tricky part about historical research. It is so important to segregate any and all knowledge that the people you are studying did not have. This is party of my professional job and it is tough. We lose a lot of analysts who can't segregate.

Wrong decisions were made. That is undeniable. But they are also, at the same time understandable.

Again, I don't see how these things can simply be written off to "understandable mistakes". It is one thing, if you test a device to the limits of your ability, and defects get by. It is something else, when you just refuse to make any worthwhile tests of a grossly defective device. (I am of course speaking of the exploder, not the torpedo as a whole.)

It is worth pointing out that Adm. Lockwood thought the matter important enough to make live test shots at Pearl Harbor. That he needed to take time and effort away from his regular duties, in a time of war, is a disgrace, IMO. What was the response from BuOrd? Did they promptly get to work fixing the defects shown? No, their response was to criticise the tests.

Really, the Mk 6 exploder, was not the Manhattan Project. The Army (and Navy) managed to come up with ways to get bombs and shells to explode on target. The 'VT' proximity fuze was fielded. It is hard to see why the Navy could not have done the same with their torpedos.