Rn vs IJN

[Wild_Bill_Kelso]

Also to be clear, WW2 era torpedo attacks are not modern self-guided torpedo attacks with modern sensor arrays, shared C3I and etc. The Japanese ships might launch 50-60 torpedoes in one small battle, and only get 2-3 hits. But that meant 2-3 enemy ships crippled or sunk, in most cases, which is at least as good as the big gunwagons did.

 

[Shortround6]

They showed how the Japanese used patterns in their torpedo attacks and were still successfully surprising the Americans in several small engagements (this was in 1943) in which the Americans were still badly underestimating the effective range of the Type 93s.

The idea that they couldn't hit targets at extended range, or that they couldn't effectively shoot spreads of these based on limited sighting data, or that radar ended their advantages in night combat, or that they didn't still ad up to a major advantage for the IJN even this late in the game is I think, clearly a gross oversimplification.

The argument is not if the Japanese got hits at long range. They did. The argument is wither that made them 2-3 time more effective than the British torpedoes and the British torpedoes were not the same as American torpedoes, even assuming the American torpedoes actually worked.

Yes the British underestimated Japanese torpedo capability. However given the limited amount of interaction between the British and the Japanese the Japanese may have underestimated the British capability. The British may have not sailed in straight lines, fat dumb and happy like the Americans did at times if the British suspected that the Japanese were in torpedo range. (British might estimate range at near 15,000yds like their own or underestimate? The Italian's had a number of torpedoes that could make 13,100yds (12,000 meters) at low speed settings. They had one that could do 50kts at very short range (3-4000meters)

A British surface torpedo (MK IX**) could travel to 15,000yds at slightly higher speed than the American MK 15 did to go 10,000yds. The British torpedo was carrying almost 50% more explosive than the American but a lot less than the Japanese.

Now at "close" range we have these combinations.
Japanese...........................48-50kts..............................21,100yds, which pretty much covers most but not all of the torpedo launches the Japanese did.
British..................................41kts...................................11,000yds
American(H).....................45kts......................................6000yds
American(M)....................33.5kts...............................10,000yds

British are about 83% as fast as the Japanese out to 11,000yds?

I won't debate the point on the air launched torpedoes, as I know the British were of good enough quality, but I would point out that most of the Japanese aircraft capable of delivering torpedoes were much better, in particular had much better range, than the FAA equivalents. The IJN also (arguably) had more effective long range land based aircraft for torpedo strikes, G3M and G4M bombers, though eventually the torpedo carrying Beaufighters would fit very well into this niche for the British.

The Torpedoes themselves show little difference, yes the Japanese had better planes, kind of.
Both countries had problems putting big torpedoes on their aircraft. Big in this case means heavy warheads on 18in (17.7) torpedoes.
The G3Ms used lighter warheads than the G4M and the Kates, but these only had a 452lb warhead.
British carrier torpedo planes used 388lbs warheads (later 432lbs with Torpex)
Late war shore based planes could carry torpedoes with 545lbs of Torpex.


The thing is that while the Long Lance showed a very marked advantage over the Allied torpedoes the same cannot be said for either the aircraft torpedoes or the Submarine torpedoes. The Japanese traded range (understandable) for warhead size with the Submarine oxygen torpedoes.
The Type 95 had a max range of 13,100yds at 45-47kts with a 405kg warhead.
The Type 95 mod 2 had a max range of 8200yds at 45-47kts with a 550kg warhead.
The Type 96 mod 2 had a max range of 4900yds at 48-50kts with a 550kg warhead. This used 38% oxygen to reduce maintenance problems.

As far as the range goes, how far can you see with a periscope? firing torpedoes over your own visual horizon is not a good idea. Also remember than the even most of the big Japanese boats only carried 18 torpedoes. Risky shots after it took weeks to get there wasn't a good idea.

 

[Admiral Beez]

Armoured Aircraft Carriers

Were the armoured carriers worthwhile?

www.armouredcarriers.com

"HMS Ark Royal (91) was designed to operate in the open waters of the Pacific, as Japan was seen as the greatest threat to the Empire in the early 1930s. Therefore it has more similarity in concept to the US carriers than the later Illustrious type carriers."

If Ark Royal was designed for ops against Japan, why wasn't her air group? Procuring slow biplane TSRs and slow twin seat fighters to face A5Ms and the like seems like blindless.

 

[MIflyer]

At the beginning of the war the USN assumed you had to fly very low and slow to drop torpedoes and have them survive hitting the water in good enough condition to work properly. In reality they eventually found that the "belly flop" technique gave worse results than dropping the torp like a bomb from higher altitude and higher airspeed and having it enter the water nose first. It sure seems like someone could have realized that the thing was designed to take loads along the forward-aft axis, not sideways. They put a wooden cap on the nose of the torps to help take up the shock and wooden fins on the rear to make sure it fell nose first. Once they got the incompetent feathermerchants out of the way they got the air dropped torps working so well that on the later PT boats they dispensed with the torpedo tubes and just dumped air launched type torps over the side. That little Revell PT boat kit reflects that configuration, while that later issued Revell 1/72 PT-109 has the torpedo tubes.

Hilarious account by a TBM pilot flying of a baby flat top at Leyte Gulf. Told he had to carry a torp and attack an IJN cruiser, he replied that he had never heard anything so absurd; the TBMs were only supposed to carry bombs. They pointed out that the cruiser was basically inside their normal traffic pattern and they badly needed to do something about it. He got rid of the torp ASAP after takeoff and was fairly sure he hit the ocean with it, but it turned out he did get the cruiser.

 

[Wild_Bill_Kelso]

At the beginning of the war the USN assumed you had to fly very low and slow to drop torpedoes and have them survive hitting the water in good enough condition to work properly. In reality they eventually found that the "belly flop" technique gave worse results than dropping the torp like a bomb from higher altitude and higher airspeed and having it enter the water nose first. It sure seems like someone could have realized that the thing was designed to take loads along the forward-aft axis, not sideways. They put a wooden cap on the nose of the torps to help take up the shock and wooden fins on the rear to make sure it fell nose first. Once they got the incompetent feathermerchants out of the way they got the air dropped torps working so well that on the later PT boats they dispensed with the torpedo tubes and just dumped air launched type torps over the side. That little Revell PT boat kit reflects that configuration, while that later issued Revell 1/72 PT-109 has the torpedo tubes.

Hilarious account by a TBM pilot flying of a baby flat top at Leyte Gulf. Told he had to carry a torp and attack an IJN cruiser, he replied that he had never heard anything so absurd; the TBMs were only supposed to carry bombs. They pointed out that the cruiser was basically inside their normal traffic pattern and they badly needed to do something about it. He got rid of the torp ASAP after takeoff and was fairly sure he hit the ocean with it, but it turned out he did get the cruiser.

Basically every country did the thing with the wooden shell and tail fins. That is what made it possible to drop torpedoes at reasonable speeds and altitudes. Prior to that torpedo bombers were extremely vulnerable unless it was at night or something.

 

[Shortround6]

Armoured Aircraft Carriers

Were the armoured carriers worthwhile?

www.armouredcarriers.com

"HMS Ark Royal (91) was designed to operate in the open waters of the Pacific, as Japan was seen as the greatest threat to the Empire in the early 1930s. Therefore it has more similarity in concept to the US carriers than the later Illustrious type carriers."

If Ark Royal was designed for ops against Japan, why wasn't her air group? Procuring slow biplane TSRs and slow twin seat fighters to face A5Ms and the like seems like blindless.

The Ark Royal was ordered in 1934 and the keel was laid in Sept 1935.
Progress in aircraft technology was pretty rapid in the mid to late 1930s. Money was a bit easier to get than the early 30s.
The Japanese were not displaying anything very advanced during the those years. While the A5M made it's combat debut in China in late 1937 aside from it's appearance and combat reports from the Chinese there wasn't a lot known about it. The Skua actually followed a rather similar time line. Except for two things.
The somewhat slow pace of British development which lead to the desire to field a totally new, better plane rather than improve the one they had which then lead to the new superplane being very late in timing which lead to the 2 ring circus (small and cheap) of buying the Fulmar as in interim plane and then buying Gladiators as an interim-interim while the Fulmars were sorted out, while the ultimate machine, the Firefly was being put on paper.

The B5N1 showed up in combat in 1938.
The British and Americans kept getting surprised by the Japanese due to cultural discrimination.
Under the best conditions seeing a B5N1 in 1938 means the RN wasn't going to get a similar plane until 1941. With the RAF hogging the limelight it was not the best of conditions for the RN.

The RAF, which had control of the RN aircraft in the 1930s was simply not looking ahead. If you are looking sideways to see what your opponent has got, you are too late.
If you see the A5M in 1937 and say "ah ha, we have to match it!" you are going to be inspecting your parachute in 1941 when you run into A6Ms.

 

[Wild_Bill_Kelso]

The problem continued for the FAA. The B5N got pretty long in the teeth, and was finally replaced by the much better B6N, but the FAA got first the Albacore and then ... the Barracuda.


View: https://www.youtube.com/watch?v=PeMvMNpvB5M

 

[Wild_Bill_Kelso]

..and then at the very end of the war, and way too late, the IJN got the extremely impressive Aichi B7

 

[MIflyer]

The RAF, which had control of the RN aircraft in the 1930s was simply not looking ahead.

And neither was anyone else. At least the USN had the TBD and was making plans that produced the TBF, so they had better than the Swordfish. But Lockheed was proving that P-38's could carry two torpedoes and with a little work the USN could have had F6F's carrying torps. It was not until the AD Skyraider that they suddenly seemed to realize that torpedo planes had to be slow and vulnerable turkeys. Of course, both dive bombers and torpedo planes had an important secondary role as scouts for the fleet. In 1940 that meant that they needed at least two crewmen to handle the radios and help with navigation. The TBF had a friggin' BIG HF radio transmitter, the same one later used in B-29's. But by 1944 improvements in radio equipment reduced the need for a separate radioman and the USN was using F6F's as scouts.

 

[Wild_Bill_Kelso]

The TBD actually turns out to be worse than the Swordfish in most respects, if you really look at them. Definitely worse than an Albacore. TBF / TBM was certainly much better than both though, even though it looks ridiculously oversized. It even worked out quite well on escort carriers, and was both a serviceable torpedo bomber and maybe more important especially for the RN, a very good carrier based ASW plane. And a half-decent general light bomber, though probably no better in that role than most fighters. You could probably have used them to run off FW 200s in a pinch too.

As for torpedo bombers having to be turkeys, I'd say look at the B6N and especially the B7N. Also the Italian fighter-bomber torpedo bombers, and the Beaufighter "Torbeau" variant, an the B-26 Marauder torpedo bomber mode (especially as used by the British), and even the Beaufort.

I think torpedo bombers went away prematurely, though they attempted to make a second wave of them right at the end of the war, most of the designs failed. The AD was the only one that worked out ultimately, but basically as a CAS aircraft.

 

[Admiral Beez]

I think torpedo bombers went away prematurely, though they attempted to make a second wave of them right at the end of the war, most of the designs failed. The AD was the only one that worked out ultimately, but basically as a CAS aircraft.

A lack of targets might have driven that decision. Postwar, had the British continued with the Fairey Spearfish and war breaks out with the USSR in the early 1950s, there's nothing to launch torpedoes at.

 

[EwenS]

A lack of targets might have driven that decision. Postwar, had the British continued with the Fairey Spearfish and war breaks out with the USSR in the early 1950s, there's nothing to launch torpedoes at.

6 Kirov class cruisers completed 1938-44
5 Chapayev clas cruisers completed 1950.
14 Sverdlov class cruisers laid down from Dec 1948 and 6 completed in 1952 and the other 8 in 1953-55. Programme terminated with another 7 under construction and another 9 planned. Nikita Krushchev cancelled the whole programme in 1954 following his rise to power on Stalin's death.

Also the ex-Italian battleship Novorossisyk (Giuilo Cesare) and cruiser Kerch (Duca D'Aosta)

 

[swampyankee]

While the immediate cause of the failureof USN torpedoes was incompetence at the USN torpedo factory, it wasn't due to its being a government arsenal: government-owned arsenals and shipyards in the US tended not to have similar problems, while technical failures, such as H-O-R submarine diesel engines, from private vendors did occur.

I suspect the root cause was the USN's general deprecation of the value of the torpedo, evidenced by the omission of torpedo magazines on the USS Ranger and, possibly, the incredibly restrictive dropping limits of USN air-launched torpedoes.

 

[Thumpalumpacus]

6 Kirov class cruisers completed 1938-44
5 Chapayev clas cruisers completed 1950.
14 Sverdlov class cruisers laid down from Dec 1948 and 6 completed in 1952 and the other 8 in 1953-55. Programme terminated with another 7 under construction and another 9 planned. Nikita Krushchev cancelled the whole programme in 1954 following his rise to power on Stalin's death.

Also the ex-Italian battleship Novorossisyk (Giuilo Cesare) and cruiser Kerch (Duca D'Aosta)

Not to mention the USSR's submarine fleet, now that torpedoes were getting homing.

 

[Thumpalumpacus]

While the immediate cause of the failureof USN torpedoes was incompetence at the USN torpedo factory, it wasn't due to its being a government arsenal: government-owned arsenals and shipyards in the US tended not to have similar problems, while technical failures, such as H-O-R submarine diesel engines, from private vendors did occur.

I suspect the root cause was the USN's general deprecation of the value of the torpedo, evidenced by the omission of torpedo magazines on the USS Ranger and, possibly, the incredibly restrictive dropping limits of USN air-launched torpedoes.

And the relative lack of testing, frankly.

 

[Shortround6]

At least the USN had the TBD and was making plans that produced the TBF, so they had better than the Swordfish. But Lockheed was proving that P-38's could carry two torpedoes and with a little work the USN could have had F6F's carrying torps.

A lot of planes were designed the way they were because that was what was possible at the time. What was possible 3-4 years later was different. What was possible 6-8 years later was way different.
The TBF went into service in 1937 with a 900hp engine. It was carrying, in theory, the best aerial torpedo in the world. At any rate, it was the heaviest at around 400lbs more than the British MK XII torpedo (26% heavier).

Strap 1950lbs under a Grumman F3F-2 biplane fighter with 62% of the wing area of the TBD and see how that works. Forget the landing gear or ground clearance.
You don't have enough wing area to handle the load, It is not "doctrine".
And in the late 30s you have crap radios. You need a rear seater to handle the communications.
F3F-2 held 130 US gallons of fuel. How far it it going to carry the torpedo once you cut the fuel to get off the deck?

Torpedo bombers of the 1930s were also level bombers ( a mistake?) and they were recon planes. With limited power engines they needed big wings to get off the decks with big loads.
Grumman TBF gained 16% wing area and 89% in power over the TBD.
BTW a USN characteristics and performance sheet gives an operational radius 95 NM for an F6F-3 with a torpedo. Not sure you want to get rid of all of your TBF/Ms in favor of Torpedocats. Early TBF/Ms were supposed to have an operational radius 240 NM for an with a torpedo and they had calculated radius with drop tanks although I am not sure that was done in service (425NM).

There was a lot more to torpedo bombing (or torpedo bombers) that just getting off the ground (flight deck) with a torpedo under the plane. That was just the start.

 

[Wild_Bill_Kelso]

While the immediate cause of the failureof USN torpedoes was incompetence at the USN torpedo factory, it wasn't due to its being a government arsenal: government-owned arsenals and shipyards in the US tended not to have similar problems, while technical failures, such as H-O-R submarine diesel engines, from private vendors did occur.

I suspect the root cause was the USN's general deprecation of the value of the torpedo, evidenced by the omission of torpedo magazines on the USS Ranger and, possibly, the incredibly restrictive dropping limits of USN air-launched torpedoes.

The really shocking thing about the US torpedo debacle isn't so much that they had the problems to begin with, but that even in the face of the loss of scores of ships and submarines and thousands of lives of US servicemen, they could not recognize let alone fix the problems. That is the part which deserves a second look with respect to modern times, because it's a theme with US procurement which haunts us periodically.

 

[RCAFson]

Armoured Aircraft Carriers

Were the armoured carriers worthwhile?

www.armouredcarriers.com

"HMS Ark Royal (91) was designed to operate in the open waters of the Pacific, as Japan was seen as the greatest threat to the Empire in the early 1930s. Therefore it has more similarity in concept to the US carriers than the later Illustrious type carriers."

If Ark Royal was designed for ops against Japan, why wasn't her air group? Procuring slow biplane TSRs and slow twin seat fighters to face A5Ms and the like seems like blindless.

Ark Royal was using monoplane DBs and biplane TBs in 1939, when the IJN was still using biplane DBs and TBs. Monoplane TBs were on order and under development in 1939, and by 1940 the monoplane folding wing Fulmar, (and the Firefly was on order and under development) with more than 4x the firepower of the A5M was in service.

You make these blanket statements without considering the facts.

 

[RCAFson]

The Torpedoes themselves show little difference, yes the Japanese had better planes, kind of.
Both countries had problems putting big torpedoes on their aircraft. Big in this case means heavy warheads on 18in (17.7) torpedoes.
The G3Ms used lighter warheads than the G4M and the Kates, but these only had a 452lb warhead.
British carrier torpedo planes used 388lbs warheads (later 432lbs with Torpex)
Late war shore based planes could carry torpedoes with 545lbs of Torpex.

SV Goodall, the RN's chief designer states that the 18in MkXII used a 440lb warhead:

An extract from D.N.C's dealing specifically with para. 8 of First Sea Lord's minute of 1st February (Enclosure 2.)

10. Para 8 of the 1st Sea Lord's minute of 1/2/42 is not understood. The derailed report M.0251/42, which contains the survivors' narratives, shows that in the first attack the ship was hit certainly by 3 and possibly by 4 torpedoes, and in the second attack, forty minutes later, by 4 torpedoes. British aircraft torpedoes that struck "BISMARCK" contained an explosive charge of 440lbs., whilse those fired by Destroyers contained an explosive charge of 750lbs. D.N.I. has stated on N.I.D. 04842/41 that Japanese aircraft torpedoes may contain an explosive charge as heavy as 867lbs., and it would appear, from a comparison of the damage caused by Japanese torpedoes to "PRINCE OF WALES" with other torpedo damage caused by German torpedoes and British charges used for experiments, that charges as large as 867lbs. Were used against "PRINCE OF WALES". Furthermore, "BISMARCK'S" standard displacement was at the very least 41,150 tons, compared with 37,500 tons of "PRINCE OF WALES", and ceteris paribus the larger the ship the better she can withstand underwater attack.

(Signed)

SV Goodall

13/2/42

 

[Wild_Bill_Kelso]

Ark Royal was using monoplane DBs and biplane TBs in 1939, when the IJN was still using biplane DBs and TBs. Monoplane TBs were on order and under development in 1939, and by 1940 the monoplane folding wing Fulmar, (and the Firefly was on order and under development) with more than 4x the firepower of the A5M was in service.

I'll still take an A5M over a Fulmar all day long... and definitely a D3A over a Skua

You make these blanket statements without considering the facts.

Pot. Kettle.