...Those Marvelous Tin Fish: The Great Torpedo Scandal Avoided

[McPherson]

In the 1960's the primary anti-submarine torpedo in the USN was the Mk 37. It was an electric torpedo, 19" diameter, swim out, pattern running, with passive/active homing. The early versions though were quite buggy, especially in the area of her batteries. They were notorious for shorting out and overheating. Hot runs, while not exactly common, happened far more often than they should have. A hot running Mk 37 was one of the early theories that tried to explain the loss of the USS Scorpion (SSN-589). This was the leading theory until later study of debris from her wreck pretty well showed that the boat's battery, not a torpedo, was what exploded and caused her loss. By the time I arrived on the USS Darter (SS-576) in 1984 the Mk 37 had been thoroughly developed and was a pretty good weapon. Along with 12 Mk 48s in our forward torpedo room, we carried two Mk 37 Mod 3 versions in our after torpedo room until 1986 when they were finally retired for good.

As long as we are in "the school of the torpedo" I thought we could look at these.

More on the Mark 6 magnetic influence feature in the Mark 5 exploder assembly.

This will clarify the generated electricity function of the impeller/generator and clarifies why Goat Island adopted the peculiar design of the original Mark 5 exploder. It also explains the CYA ball switch feature added late war and highlights how even after the Mark 6 influence feature/Mark 5 exploder assembly was discredited and/or field modified to sort of work the Rube Goldberg crowd found new ways to infuriate and bedevil navy armorers.

Briefly I will add my own "opinion" of this debacle.

It does not matter where the impeller is set or how it operates with respect to torpedo motion as long as the generator produces current load to a discharge capacitor to operate the pickup coil and/or the solenoid (see Pi-2 pictures and compare to the American unit here. Manual on the Pi-1 and 2 torpedo exploders for the German G-7 torpedo family described here as the USN understood the device.). HOWEVER... the Germans used a battery. and they used a linear action in the direction of acceleration arming path. The Whitehead torpedo originally used a set screw impeller mounted on the nose that spun a set of revolutions that operated a spindle cam assembly that unlocked the safety gate on a contact pistol. This was an arming safety. Virtually idiot proof, it relies/relied on the torpedo to swim a period of time away from the launch unit before it armed. The same impeller setup could do double duty as an electric generator. The spinning screw provides the armature rotation. Or the Goat Island "geniuses" could have put the generator in the power unit attached to one of the turbines. (More on that PU in a moment.)

Since the Mark 37 torpedo has been mentioned, here is some information on those fish.

Mark 37C torpedo (Otto fuel).

Mark 37 electric.

Complex does not begin to describe their design and use.

Some info on the WW II tools of the submarine trade.

But back to the design of the American torpedo. Here are a few things to note.

1. Given the technology of the day (or even today) a piston driven internal combustion engine will give more "run time" per given amount of fuel/watts generated than a turbine. This means that while the turbine is lighter and in many cases easier to miniaturize and manufacture, if a three cylinder or four cylinder 150 kwatt engine can be fitted into a torpedo afterbody power unit in the same volume as the two turbine Goat Island setup, that probably will give more run time on the same fuel. If the engineers can swash plate the engine so that it dispenses with the crank and instead roller coasters the torpedo screw armature, that is even better as far as space savings and seawater cooling jacket flow is concerned. BUT then someone needs to design a contra-rotator gearbox and opposite spin flywheel weight to counteract swashplate torque loads. I actually like that as an engineering solution because active angular momentum cancellation through gyroscope effect cures a huge torpedo problem as a good side effect; nose wander. That torpedo will point.

2. A linear fuse in the direction of acceleration with an inertia hammer ball switch saves space in the warhead. An external armature impeller/screw arming safety feature also saves volumetric space better used for hexanite. As for the prong vanes, levers, "whiskers" in keeping with my mania for double duty purpose and features, these "fins" can serve as fore control as well as contact levers/horns to set off the torpedo at oblique strike angles. Note above how the German sailor carries the Pi-2 assembly like a baby? NOW after reading the Mark XVIIII service manual and what bad things happen when you have to dismount the warhead to get at the exploder to service it, does it not make sense to have a SCREW IN MODULE that just slides into the torpedo nose as a complete assembly?

3. Which brings me to the problem about the earth's magnetic field and compasses and how to detect land mines and photo-electric eyes and other goo-gaws. I find it interesting in reading about Christie's little boat ride off Ecuador when he made those tests using a destroyer to fire practice torpedoes at the USS Indianapolis, that to prove the influence feature tripped at the proper time he used an electric eye put into the exercise fish to time the shadow of the cruiser as the torpedo passed under the Indianapolis to compare that to the trip time of the Mark 6 influence feature circuit. NOW THINK ABOUT WHAT I JUST WROTE.... One Mississippi, Two Mississippi, Three Mississippi... What the bloody hell was wrong with Christie? He used an electric eye as a trip feature in the cockamamie torpedo to check another trip feature in the same torpedo! Uhm. He apparently knew the photoelectric eye would work as an under the keel influence device to measure how the magnetic influence feature was working. Why didn't he use the photoelectric eye setup as a fusing feature?

4. John Q. Landmine. Once upon a time, the British army was worried that the Germans would do something cute like apply naval mine warfare to tanks. The British army, being who they were, decided it would be a good idea if they could devise a way to find these mines by not rolling tanks over them. Since the mines expected would be buried in the dirt and should be cheap, plentiful, and made out of steel, a magnetic means to find aforesaid mines would be a bit better than Private Fumbles poking the dirt with his bayonet. The British army guys came up with a contraption that used a magnetically sensitive switch hooked to a tone emitting circuit that would detect the presence of a mass of metal that distorted the magnetic field. They did not use the Earth's magnetic field to do this. Great minds hunting for German land mines think alike. The American army had a slightly different approach that did exactly the same thing. (1936). Someone should have talked to these "army" guys. Both the RN and USN were guilty of the same exact hubris.

Anyway... Goat Island sure could have used a manufacturing process analyst and a systems logic engineer.

 

[phx1138]

used an electric eye put into the exercise fish to time the shadow of the cruiser as the torpedo passed under...

...used a magnetically sensitive switch hooked to a tone emitting circuit ...

You're absolutely right.

Except, somehow, I suspect the engineers at NTS would have found some way to screw it up.

That's why I favor contact: KISS.

For PTs, the tube launch system always struck me as pretty stupid: you're adding, what, 20,000 pounds of tube & torpedo. Why not use the Mark 13 & drop collars?

 

[Draconis]

As long as we are in "the school of the torpedo" I thought we could look at these.

3. Which brings me to the problem about the earth's magnetic field and compasses and how to detect land mines and photo-electric eyes and other goo-gaws. I find it interesting in reading about Christie's little boat ride off Ecuador when he made those tests using a destroyer to fire practice torpedoes at the USS Indianapolis, that to prove the influence feature tripped at the proper time he used an electric eye put into the exercise fish to time the shadow of the cruiser as the torpedo passed under the Indianapolis to compare that to the trip time of the Mark 6 influence feature circuit. NOW THINK ABOUT WHAT I JUST WROTE.... One Mississippi, Two Mississippi, Three Mississippi... What the bloody hell was wrong with Christie? He used an electric eye as a trip feature in the cockamamie torpedo to check another trip feature in the same torpedo! Uhm. He apparently knew the photoelectric eye would work as an under the keel influence device to measure how the magnetic influence feature was working. Why didn't he use the photoelectric eye setup as a fusing feature?

The photoelectric eye would not function at night or with any amount of cloud cover that will prevent the target ship from throwing a well defined shadow. Heck, even with a nice sunny day and just before the torpedoes arrive a big fluffy cumulus cloud drifts in front of the Sun and ruins the attack. Depending on how the photoelectric eye is setup the long shadows of early morning or late evening might not trigger it properly.

The photoelectric eye was useful as a test rig but I think it would have too many restrictions for active service. It would have been great if the the U.S. Navy could have gotten the magnetic exploders to work and work reliably.

 

[phx1138]

The photoelectric eye would not function at night or with any amount of cloud cover that will prevent the target ship from throwing a well defined shadow. Heck, even with a nice sunny day and just before the torpedoes arrive a big fluffy cumulus cloud drifts in front of the Sun and ruins the attack. Depending on how the photoelectric eye is setup the long shadows of early morning or late evening might not trigger it properly.

The photoelectric eye was useful as a test rig but I think it would have too many restrictions for active service. It would have been great if the the U.S. Navy could have gotten the magnetic exploders to work and work reliably.

I have a suspicion wave action would be enough.

For all that, it's a completely unnecessary complexity, in line with American love of complexity for no good reason. The Mark X, OTL, worked just fine for all the Mark XIV's assigned tasks, & that was with a smaller warhead. So why in the world does NTS need to screw around with what amounts to a SP magnetic mine?

 

[DaveJ576]

NEW PATHS, “ONE HELL OF A WALLOP”, AND SOME FORTUNATE ANGINA – 1935-1940

The Navy’s Bureau of Aeronautics (BuAer) had initiated a project to develop a new torpedo plane in 1934. The T4M and TG biplanes were well beyond their age and the fleet was desirous of a plane that could take advantage of the work being done on the Mk 13. Buoyed by the positive reports of the Mk 13 tests by Naval Aviators assigned to the Fleet Liaison Office, BuAer kicked the project into high gear. The Douglas Aircraft Company was declared the winner of the competition and their design, the XTBD-1 Devastator was delivered to the fleet on 24 April 1935 for testing. The Navy’s first carrier-based monoplane, the Devastator was a very advanced aircraft for the time. Its’ low wing and semi-retractable landing gear provided great advantages in drag reduction and safety. The fleet marveled at the powered upward folding wings and 206 mph top speed, an increase of over 60 mph on the TG-2. Initial testing went quite well and the TBD-1 entered fleet service with squadron VT-3 in the summer of 1937. Fleet aviators found that the Mk 13 could be launched without problems at the top speed of the Devastator and up to 600 feet in altitude. At these drop parameters the rates of hot, straight, and normal runs of the now fully developed Mk 13 approached 100%.

After taking a year to set up his administration and get his recovery agenda set in motion, President Roosevelt was now eager to take a look at how his pet project had progressed over the years. Despite staying in touch during his illness and his political activities as governor of New York, Roosevelt had felt somewhat detached and wanted a full update on the Council’s activities. Accompanied by the Chief of the Bureau of Ordnance Rear Admiral Harold R. Stark, the President toured Newport, Alexandria, and the Bliss company. He witnessed live tests on the TTRA, embarked on the brand-new destroyer USS Hull (DD-350).

Deeply impressed, Roosevelt returned to Newport and sat in on a meeting of the Council. He was especially keen on new development projects. He was briefed on the Ralph Christie led Project G 49, which was an effort to develop a very long-range weapon powered by a form of hydrogen peroxide called Navol. While work on the project had proceeded reasonably well, the head of the FLO expressed deep reservations about using Navol powered torpedoes aboard ship. Navol was a tricky and dangerous substance to handle. The torpedoes would require special handling and vastly different equipment aboard ship, which would greatly alter designs, especially for submarines. There was also a great deal of concern about battle damage to the Navol equipment and storage tanks, fears of hydrogen peroxide explosions were at the forefront of the concerns.

The FLO and the Council however were much more enthusiastic on the concept of the electric torpedo. Low level development work had been ongoing at Newport for almost 10 years, and when combined with advances made in the electrical industry by companies like Westinghouse, Exide, and General Electric it was felt that an electric torpedo was now well within the capabilities of the establishment. Besides, the fact that it was wakeless provided the fleet with a substantial tactical advantage. The project prototype had been re-designated as the Mk 18. All they needed to proceed was funding.

He was updated on the progress of the Mk 6 exploder project. The Indianapolis tests had buoyed the effort, but subsequent testing had once again showed that the damnable device was maddeningly inconsistent.

Finally, he was briefed on the search for a new explosive. In 1923 the Council established The Committee for Explosives Research within their ranks to investigate alternatives to TNT. The progress had been slow, but recent cooperative work spurred by the Committee between the military science establishments in Great Britain and the United States had borne fruit. A new industrial process for efficiently and inexpensively manufacturing a compound called hexogen had been developed and showed great promise. When combined with TNT and other compounds as a booster, a powerful new explosive could be developed.

Roosevelt and Stark sat in the background of the meeting and listened intently to the debates, some of which where quite heated, especially in the area of the Navol torpedo. In the end, when asked for his input the President decided on four courses of action:

1. Project G 49 would be relegated to a technology research project only for now. He agreed that the nature of the Navol project would cause complications and issues that were unwarranted at the present time. With the tried and tested performance of the Mk 13, 14, and 15 weapons this new path seemed redundant. Perhaps sometime in the future it could be pursued again.

2. He heartily endorsed the Mk 18 project, believing the concept to be the right direction. He promised the Council would get the funding needed to move the project forward.

3. He and Stark were very enthusiastic about the hexogen research and realizing the Depression recovery benefits of seeding industry with the funding necessary to initiate production, they fully endorsed this program.

4. The Mk 6 project would be given three more years to produce a fully operational product or it would be abandoned.

The Council set about on its new Presidential sanctions with gusto. Bliss was handed overall responsibility for refinement of the Mk 18 weapon, and they engaged Westinghouse and Exide as partners in the project. The learning curve was still quite steep, and work proceeded in fits and starts for the next 6 years.

Within 10 months of the meeting, the DuPont Company, sanctioned by BuOrd and in cooperation with the Waltham Abbey Royal Gunpowder Mills in Great Britain tested the first formulation of a new explosive compound called Torpex. It consisted of 40% TNT, 18% powdered aluminum, and 42% RDX (a refinement of hexogen). The test was conducted at the Naval Proving Ground at Dahlgren, Virginia. A member of the submarine contingent of the FLO, LTjg Dudley W. Morton was present for the test, and suitably impressed, wrote in his report to the Council that torpex “packed one hell of a wallop!” Using seed money from the Navy budget, DuPont immediately began set up work for a new production facility for torpex, sharing a license with Waltham Abbey, with the goal of having it available for use by the Navy and War Departments no later than 1938. Further research was necessary, but DuPont was confident they could meet the goal.

Ralph Christie had returned to the fleet and had turned the Mk 6 project over to his deputies. However, alarmed by the President’s three-year proclamation, he once again interjected himself into the project. He designed a new testing regimen and once again the old Ericsson was hauled out of storage in Philadelphia and was used in a renewed series of tests. This time instead of being moored the old tub was towed behind a fleet tug off the Virginia Capes and a series of Mk 14s and 15s with exercise heads installed were fired at it. The Ericsson was towed at a variety of speeds and courses and in differing sea states. The Mk 6 was back to its’ old tricks and it only worked about 15% of the time. Supremely frustrated and thinking that maybe the old destroyer was the cause of the problems, Christie disposed of the Ericsson with a Mk 14 equipped with the standard (and well proven) Mk 5 contact exploder fired from the submarine Cuttlefish (SS-171). The Mk 14 was equipped with a prototype torpex warhead and the remnants of the Ericsson sank less than 30 seconds after the detonation.

He cajoled the Council into granting him another target ship and this time was given access to the old armored cruiser Missoula (CA-13). The Mk 6 team did everything they could think of to get the Mk 6 to work. The Missoula was first tested off the Virginia Capes, then down in the Caribbean off Panama, then was towed all the way to Hawaii and was fired on by Mk 15s on the TTRP off Kahoolawe. By thorough and detailed preparation work in the lab, they were only able to get the exploder to work approximately 22% of the time. Frustration was mounting as time ticked away, but the team refused to follow any other technological path. Christie would not hear of it and stuck to his convictions.

The inability of the Mk 6 team to produce consistent results lead the chairman of the Council Charles Edison to the only possible conclusion. By the fall of 1937 he had enough and on the 3rd of October officially halted any further work on the Mk 6 exploder. The team was disbanded and the remaining equipment was locked away at Newport for possible future development. Ralph Christie, totally deflated at the twin failures of the Navol and Mk 6 projects returned to the fleet and gave top-level service for the rest of his career.

On the morning of 18 August 1940, Captain William H.P. “Spike” Blandy was having breakfast with his wife at home when he suddenly felt stinging pains in his chest. Short of breath and in a lot of pain, his wife rushed him to the Naval Hospital at Balboa in San Diego. Over the next two days he suffered a series of minor heart attacks which did permanent damage to his heart. His strength of character and robust constitution allowed him to survive, but he would not be able to continue his naval career. He was medically discharged from the Navy three months later and he and his wife retired to a comfortable home in Seaford, New York.

Author’s note: Such was the pace of aircraft development in the late 1930’s that an aircraft that was on the cutting edge of technology in 1935 would be so hopelessly outdated just 6 years later. It must be remembered that the TBD Devastator was an outstanding aircraft when introduced in 1935, but was quickly overtaken by technology. Its’ days were still numbered, but perhaps a portion of the criticism leveled at it would have been milder if the damned Mk 13 had worked the way it had been designed.

The Mk 16 and 17 Navol torpedoes could have been our answer to the famous Japanese Long Lance torpedo. There was really nothing to stop us from developing those weapons prior to the war, except for a rigid adherence to tradition and an overly cautious approach to shipboard safety. I deliberately sidestepped their development here because their use would have caused major changes in submarine and destroyer design, and that would have introduced butterflies in the timeline that I did not want to deal with. The story is interesting enough without all of those complications. However, I will admit the possibilities are fascinating…

In the OTL Newport dragged its collective feet on the development of an electric torpedo and thus we started very late and relied on captured German models as a guide. Even then Newport badly mis-managed the project, forcing BuOrd to turn the whole shebang over to private industry. I have tried to correct that ITTL.

I will admit that there is a slight amount of hand-waving on my part when it comes to torpex. In the OTL the science involved was still struggling right up to the start of the war. After consulting with McPherson on it I decided that I wanted to accelerate that part because it would have given the Council an added incentive to drop the damnable Mk 6. ITTL Mush Morton was his usual eloquent self in his report to the Council, and in the OTL made a very similar comment after seeing a torpex detonation against a Japanese ship.

Yes, if Newport had conducted even a moderate amount of testing on the Mk 6 during the 30’s the results that I described would have been revealed. I believe that even the normally stodgy and reticent Newport would have been forced to abandon the project with the raw data staring them in the face. I shake my head every time I think about it.

Spike Blandy was the head of the Bureau of Ordnance during the first half of WWII and I have never been a fan of his. His intractable denial that there was anything wrong with the torpedoes was a MAJOR factor in the Great Torpedo Scandal. How many men died because of his rigidness is incalculable. Blandy and Lockwood damn near got into a fistfight over the issue. I have relegated him to the dustbin of history here.

 

[McPherson]

No atomic playboy, yeah! Mark 5 exploder with that damned impeller setup and the soon to be discovered Mark XVIII maintenance horror show that comes with it as a corollary, groan. Nothing's perfect (G7 series depth control was an air bladder problem for the Germans forever.), but can some bright boy at Bliss have a stroke of inspiration?

 

[tomo pauk]

Yay, update! Thank you

 

[phx1138]

NEW PATHS, “ONE HELL OF A WALLOP”, AND SOME FORTUNATE ANGINA – 1935-1940

This is another fine piece of work. You've managed to credibly show what could have (should have!) been done.

Within 10 months of the meeting, the DuPont Company ...

I didn't know about the possibilities here, but this IMO is entirely reasonable. I think you can justify the OTL bugs being ironed out sooner due to a (slightly) different team of people, changed timing, so forth.

[Christie] returned to the fleet and gave top-level service for the rest of his career.

This is my only gripe. My own bias against him is strong, & I'm not sure I'm entirely satisfied if he's not burned at the stake.

However, if he dies in obscurity as head of a failed technical program, I can live with it. Send him to ETO as Edwards' CoS, or something, & keep him out of Oz.

Nice job on Blandy, too. (Do I recall correctly it was Blandy who arranged for Lockwood to get the Inspector General posting that Lockwood detested?)

 

[McPherson]

About a photoelectric eye. Lots of good arguments against, but one thing is certain... at Lingayan Gulf six transports would have been sunk in deep water.

And if you do have to have a proximity fuse, daylight at 40% is better than 24 hours at 15%. And there is always the metal detector approach. Just make sure your arming safety lock disengages well away from the sub or destroyer.

 

[marathag]

Author’s note: Such was the pace of aircraft development in the late 1930’s that an aircraft that was on the cutting edge of technology in 1935 would be so hopelessly outdated just 6 years later. It must be remembered that the TBD Devastator was an outstanding aircraft when introduced in 1935, but was quickly overtaken by technology. Its’ days were still numbered, but perhaps a portion of the criticism leveled at it would have been milder if the damned Mk 13 had worked the way it had been designed.

The TBD was a large aircraft, similar in size and wing area to the later Douglas Skyraider.
Quite a bit difference in engine power, though. A TBD-2 with a larger engine would have helped keep it in the running for WWII.

Otherwise, it would be like expecting the first Spitfire to be competitive with its original engine

 

[McPherson]

The TBD was a large aircraft, similar in size and wing area to the later Douglas Skyraider.
Quite a bit difference in engine power, though. A TBD-2 with a larger engine would have helped keep it in the running for WWII.

Otherwise, it would be like expecting the first Spitfire to be competitive with its original engine

A larger engine means a heavier engine, which in turn means a redesigned air-frame to ballast the aircraft properly. It is a flying bridge load suspended from its single fulcrum pivot point, its main wing. Heinemann was a super-genius, but even he would not be able to plug a 1500 kWatt engine on the Devastator without adding length to the tail.

 

[tomo pauk]

The TBD was a large aircraft, similar in size and wing area to the later Douglas Skyraider.
Quite a bit difference in engine power, though. A TBD-2 with a larger engine would have helped keep it in the running for WWII.
...

A larger engine means a heavier engine, which in turn means a redesigned air-frame to ballast the aircraft properly. It is a flying bridge load suspended from its single fulcrum pivot point, its main wing. Heinemann was a super-genius, but even he would not be able to plug a 1500 kWatt engine on the Devastator without adding length to the tail.

I'm sure that no-one would've try to install a 2000 HP engine on a Devastator. However, installing even a 1100 HP Twin wasp instead of the 900 HP one leaves a lot of elbow room for improvements, while not paying a serious weight penalty. The wing was, after all, bigger than on the Bf 110, the Devastator possesed plenty of lift.

 

[McPherson]

I'm sure that no-one would've try to install a 2000 HP engine on a Devastator. However, installing even a 1100 HP Twin wasp instead of the 900 HP one leaves a lot of elbow room for improvements, while not paying a serious weight penalty. The wing was, after all, bigger than on the Bf 110, the Devastator possesed plenty of lift.

There is a difference between 1935 discontinued air frames and 1939 airframes. I love the Avenger, but to be frank, it was a bit too big and heavy for its original mission profile. It had the advantage of being ready and mass produceable which its rival the Sea Wolf did not possess. Even so, I wish either plane had replaced the Devastator. by 1940. The Devastator was toast by 1939, just 4 years after introduction.

 

[tomo pauk]

There is a difference between 1935 discontinued air frames and 1939 airframes. I love the Avenger, but to be frank, it was a bit too big and heavy for its original mission profile. It had the advantage of being ready and mass produceable which its rival the Sea Wolf did not possess. Even so, I wish either plane had replaced the Devastator. by 1940. The Devastator was toast by 1939, just 4 years after introduction.

Oh, don't get my wrong - I'm all for technical advance, and US industry was certainly able to produce a better naval attacker than it was the Devastator. As it was the case historically.
We can recall that Avenger was the toast when flew unescorted into the Kido Butai hornet's nest. Attack package need to be well escorted, while the friendly fighters employ frei jagd before the inbound strike arrives to make the defenders busy. That is doubly the truth for the OTL USN torpedo-bombers where the launch parameters of torpedos dictated slow & low approach thus made the IJN pilots racking their scores. Unfortunately, the USN fighters were unable to provide meaningful escort on many occasions in 1942.

 

[McPherson]

Oh, don't get my wrong - I'm all for technical advance, and US industry was certainly able to produce a better naval attacker than it was the Devastator. As it was the case historically.
We can recall that Avenger was the toast when flew unescorted into the Kido Butai hornet's nest. Attack package need to be well escorted, while the friendly fighters employ frei jagd before the inbound strike arrives to make the defenders busy. That is doubly the truth for the OTL USN torpedo-bombers where the launch parameters of torpedos dictated slow & low approach thus made the IJN pilots racking their scores. Unfortunately, the USN fighters were unable to provide meaningful escort on many occasions in 1942.

And here is where I think the PoD could have been generated at BuAir. If those people had done a proper systems analysis, they would have understood quite quickly that a scout fighter bomber as a companion to the torpedo bomber was entirely rational in USN doctrine. It would be a big tough plane (2 man crew, emphasis on speed, range, and lifting ability) that could carry a bomb, dive bomb and still fight as a fighter after it bombed. The Dauntless was half a step in the right direction. Make it a full step and produce something like the Douglas BTD-1 Destroyer in 1941 with the engines then existent.

 

[Butchpfd]

And here is where I think the PoD could have been generated at BuAir. If those people had done a proper systems analysis, they would have understood quite quickly that a scout fighter bomber as a companion to the torpedo bomber was entirely rational in USN doctrine. It would be a big tough plane (2 man crew, emphasis on speed, range, and lifting ability) that could carry a bomb, dive bomb and still fight as a fighter after it bombed. The Dauntless was half a step in the right direction. Make it a full step and produce something like the Douglas BTD-1 Destroyer in 1941 with the engines then existent.

For it'ss ize and carrying capacity, IMO, the TBF could have handled 2-.50's on cowl or 2-4 in wings and dual .50 cals in turret instead of singles

 

[McPherson]

For it'ss ize and carrying capacity, IMO, the TBF could have handled 2-.50's on cowl or 2-4 in wings and dual .50 cals in turret instead of singles

You have to take in account the trade in weight of fuel, added drag and loss of speed and lift these modifications cause. For my PoV, I would want to eliminate as much clutter, drag and wasted weight the third man, and the useless ventral and dorsal turrets caused and take that freed up weight in speed, payload and range.

As Tomo Pauk pointed out, the TBF was a sitting duck without strong fighter cover. The torpedo plane is a bomb truck, and later a platform for electronic warfare and airborne early warning and ASW gear. The second man had to be retained for those oddments, but the weapons and the third man were pitched (including the heavyweight bomb or torpedo) to shoehorn in the radar or ASW gear.

YMMV. There is a strong argument and case for trying to upgun the Avenger as you suggested. It just depends on how people think it should be used. In other words, in that era, you are not wrong to suggest what you did.

 

[DaveJ576]

Surprise! I actually had another chapter ready so here it is! See below.

 

[DaveJ576]

GEARING UP FOR WAR – 1941

President Roosevelt declared a “limited emergency” on 08 September 1939 in response to the initiation of war in Europe. This declaration freed up funding for the military and served as a priming pump to the armed forces and the industry that supported it. The Navy asked for and got a new torpedo plane project initiated as a replacement for the rapidly obsolescing TBD Devastator. Grumman made quick progress on the new bomber and by August 1941 the first prototype had flown and Grumman was standing up a full production line in Bethpage, New York. The new aircraft had a substantial performance increase over the TBD and this prompted the Council to develop a new testing program to expand the drop parameters of the Mk 13 in order to take full advantage of the new planes’ performance. The new test series was scheduled to begin in March 1942.

There was a great deal of concern over existing torpedo inventories. It became Navy policy that for every destroyer torpedo tube there should be three torpedoes, for every submarine tube six torpedoes, and for every torpedo plane five torpedoes. Plus, additional weapons were needed for practice shots and replacements. As the reality of the deteriorating world situation became clear, the Council realized that a lot more weapons would be needed if and when the shooting started. Fortunately, government seed money during the 30’s had allowed both Bliss and Alexandria to keep their production capabilities in a fully modern state, and Bliss had implemented efficiency efforts at both facilities. Plus, using the seed money both locations had built extra production space that had laid dormant for just such an emergency. By the spring of 1941 the Navy was taking delivery of 600 new weapons each month. A report submitted to the Council in April 1941 showed that Bliss was fully capable of ramping up to nearly double that rate within 120 days of getting the order to proceed, with NTS Alexandria capable of similar numbers. By the fall of 1941 the Navy’s fear of a torpedo shortage in the event of war had been largely alleviated.

To simplify things, the Navy made the decision to thin out the stocks of existing older weapons. The Mk 7 Mod A, 2A, and 5A aerial torpedoes along with the Mk 9, 11 and 12 weapons were all pulled from the inventory and scrapped. They were all obsolete once numbers of the newer weapons arrived. A handful of the submarine type Mk 9 Mod 1B weapons remained in the inventory at Cavite in the Philippines as a stop gap until deliveries of the Mk 14 caught up in late 1941. The 18” Mk 7 Mod 0 torpedo was retained in limited numbers so that it could equip the old O-class submarines that were being brought out of mothballs in 1941 to train new submarine crews.

By early 1941 the Navy was well along in the concept development of the Patrol Torpedo boat. Having renewed an interest from WWI in small torpedo armed boats, the Navy initiated development work in 1938. By late 1939 the Electric Launch Company (ELCO) had refined its 70-foot design and the Navy contracted it to build 11 copies of the PT-9. The main armament for the boat was four Mk 8 torpedoes in two trainable black powder fired torpedo tubes on each side of the boat. Company testing of the boats showed that they had promising performance characteristics, but they seemed overweight and sluggish. During a March 1941 open ocean run from Key West to New York the boats pounded heavily in the waves and all of them suffered some sort of structural failure. It became plainly apparent that the boat needed to be bigger and the topside weight had to be reduced.

On the evening of the squadron’s arrival in New York two of the ELCO designers, Irwin Chase and Glenville Tremaine sat in a bar outside the Brooklyn Navy Yard and dejectedly mulled the situation over a few beers. After a bit they were joined by a young Navy officer, LT John Bulkeley. He was a member of the FLO at Newport and had sought out the designers to discuss the disappointing results of the run. Talking long into the night the three men discussed ways to improve the boats’ performance. Bulkeley was fully aware of the capabilities of the Mk 13 and suggested replacing the Mk 8s with Mk 13s. The Mk 8 had to be launched in a upright horizontal position to avoid tumbling the gyro, hence the tube launch method. The advantage of the Mk 13, being designed for aerial launch was that it was much more tolerant to gyro tumble and thus could be simply rolled off the deck from a light weight launch rack. The weight savings would be on the order of 7000 lbs when taking into account the lighter Mk 13 and the greatly reduced weight of the launching system. The three men literally made notes and calculations with pencils and notepads from the bar and came away convinced that this was the way to go. Chase and Tremaine excitedly returned to their plant and immediately fabricated four launch racks while Bulkeley went to the Council and begged for four Mk 13s to test the new concept with. Three weeks later the repaired PT-11 was fitted with the new racks and successfully launched the four Mk 13s while doing 35 knots on the range in Maine.

Greatly encouraged by the results, ELCO incorporated the new racks into the design of their 78-footer which after a summertime competition was chosen by the Navy, along with designs from Higgins Industries and the Huckins Yacht Corporation for full production, with the Navy dictating that the ELCO torpedo rack design be used by all three companies. The weight savings also allowed the incorporation from the start of a Mk 2 20 mm Oerlikon rapid fire cannon on the aft deck, to supplement the normal gun armament of two twin mount .50 caliber M2 machine guns. The first squadron to deploy overseas was MTB Squadron 3 with 78-foot ELCOs and they arrived in the Philippines in September 1941 with Mk 13s and 20 mm Oerlikons, and were under the command of none other than LT John Bulkeley.

Persistent and lengthy development work on the Mk 18 by Bliss, Westinghouse, and Exide had yielded results by late 1941. It had been a frustrating R&D period, with one problem after another cropping up and demanding attention. Issues with short circuits, excessive hydrogen production from the batteries, varying voltage in different water temperatures (and thus varying speeds and ranges) had all bedeviled the development team. The prototypes had also shown a propensity towards requiring detailed and intensive maintenance, which obviously was not always obtainable onboard a submarine. On one occasion a tube loaded prototype weapon short circuited onboard the submarine Sturgeon (SS-187) and the subsequent hot run very nearly destroyed the submarine when it exploded shortly after being ejected from the tube. One by one these problems were addressed by the combined industry team and with assistance of technicians from Newport were all eventually solved. Since Bliss was fully involved with steam torpedo production the tooling was handed over to Westinghouse and on 05 December 1941 the first low rate production model rolled off the production line and was immediately delivered to Newport for subsequent validation testing.

Author’s note: And so the stage is set for the great test of Roosevelt’s torpedo infrastructure. Will it make a difference? We shall see!

One of the other factors in the scandal was Newport’s inability to adequately ramp up production. At the start of the war, with three shifts running and over 3000 workers employed they were still only turning out about 2.5 weapons per day. The reasons were multi-fold, but primarily rested with the fact that Newport was primarily an R&D center and was not in the production mindset. All three of the torpedoes were finely crafted works of art and in some cases parts were individually fitted and thus not identical. This practice did not lend itself to mass production. The overall shortage of torpedoes drove home the need to conserve torpedoes and reinforced in the minds of men like Christie, Blandy, and Admiral English in Pearl Harbor the need to rely on the Mk 6 exploder to solve their problems. It added to the reluctance to give the damn thing up.

The early performance of the PT boats suffered in large part because of the black powder fired tube system they carried. The tubes were very heavy and did not work reliably but without a viable alternative in the OTL it was their only choice at the time. A large number of the easier to handle and perfected Mk 13 gave them a choice ITTL and I butterflied in John Bulkeley to give them the inspiration. In the OTL the decision to convert to Mk 13s only happened in 1943 and it went down similar to how I described it, only with different players.

Working up a viable electric torpedo by the start of the war would not have been easy OTL, but I am convinced that with the right support and funding it could have been done. It will be interesting to explore how this will affect this timeline.

 

[marathag]

The Navy asked for and got a new torpedo plane project initiated as a replacement for the rapidly obsolescing TBD Devastator. Grumman made quick progress on the new bomber and by August 1941 the first prototype had flown and Grumman was standing up a full production line in Bethpage, New York.

From OTL, what fate on the Vought Seawolf here?

From the wiki
Vought, who designed the then XTBU-1 Sea Wolf to a 1939 US Navy requirement. The first prototype flew two weeks after Pearl Harbor. Its performance was deemed superior to the Avenger and the Navy placed an order for 1,000 examples.[1]

Several unfortunate incidents intervened; the prototype was damaged in a rough arrested landing trial, and when repaired a month later was again damaged in a collision with a training aircraft. Once repaired again, the prototype was accepted by the Navy. However, by this time Vought was heavily overcommitted to other contracts, especially for the F4U Corsair fighter, and had no production capacity. It was arranged that Consolidated-Vultee would produce the aircraft (as the TBY), but this had to wait until the new production facility in Allentown, Pennsylvania was complete, which took until late 1943.