Japanese aircraft were behind in timing to Allied aircraft.

[Wild_Bill_Kelso]

AFAIK there was not a general switch to the Aboukir type. It was purely a local modification made in Egypt.

Aboukir was an RAF base in the Nile Delta from pre-war days on which was based an RAF MU. Their filters were an effort to improve on the Vokes type which was standard on the Spitfire V Tropical versions manufactured in Britain for overseas use. I don't think it has ever been clear just how many were converted. One other suggestion I've seen is that the need for a local modification became apparent with the arrival of the first PR Spitfires in the Med. These PR. IV arrived without the Vokes filter.

Spitfire Aboukir filter vs Vokes?

Does anyone know why the Aboukir filter should be any better than the Vokes one? Both rely on passing the air through a convoluted filter, which removes any of the pressure recovery that could have been expected from a well-designed intake. The Vokes has greater surface area, hence more skin...

www.key.aero

And it seems that there were at least 2 types of Aboukir filter

Abukir filters

Dear Forumites I'm almost 100% sure that similar question has occured before but UG hasn't help me with it. That's why I decided to ask it here as there are lots of people who have huge knowledge about Spitfires. I have a question about famous "custom" dust filters made by MU in Abou Kir/Abukir. ...

www.britmodeller.com

Good stuff. It's funny how much of this stuff about the filters seems to be on the modeling forums, that is what I was finding too.

Yes i was aware that Aboukir was one of the depot bases. I had been under the impression that they had made a general transition away from the vokes type, but I guess by the time this was getting underway the war was already shifting north into Italy where the problems with dust were not as severe and I think they stopped using tropical filters altogether eventually.

And I guess they never brought this useful innovation over to the Pacific, but when you see the later model Sptifires (Mk VIII etc. ) in the Pacific Theater they don't seem to have the big vokes type filter housing.

 

[Wild_Bill_Kelso]

The interesting conclusions that the author draws is that long range torpedo fire was not a winning proposition. The most successful torpedo attack was Tassafaronga and there the torpedoes were launched at close range, certainly with range of US torpedoes.

One of the myths is that the Japanese doctrine was to launch their torpedoes and then wait for them to strike before opening fire. I cannot find too many examples of that. In most instances they did both at the same time or waited for gunfire to weaken the enemy first.

Based on the attached study I did an analysis of the action at Savo Island
The only Japanese cruiser to launch before opening fire was the Chokai. During the attack on the southern group the Chokai launched 4 at 10,000 yards all of which missed. 8 minutes she opened fire.
The Canberra was not hit by any Japanese torpedoes. Her damage was exclusively due to gunfire. The Chicago was hit by two torpedoes (1 was a dud) fired by Kako at a range of 3600 yards. The Chicago was not taken out by the hit as the damage was minimal. The Chicago took herself out of the battle. Her captain was due to be censured for his poor performance and this resulted in him committing suicide.

During the attack on the northern group the Chokai launched 4 at 9,500 yards. 3 minutes later she opened fire. The torpedoes arrive at the Vincennes 5 minutes after the gun battle had begun. At this point uncontrollable fires were raging and extensive damage to the Vincennes had been done by Kako's gunfire. There are debates on how many torpedoes hit with one certain and 1 or 2 more which may have actually been shell hits below the water line. I'm inclined to believe that two or three torpedoes hitting out of 4 is a highly unlikely event.
View attachment 732969
The torpedoes which struck Quincy (1 Type 93 and 2 21 in) were launched well after the gunfire commenced and at a range of only 3,000 yards. An additional Type 93 stuck the Vincennes 15 minutes after that battle started and it was fired from a range of only 2,400 yards.

Reading through the attached document it becomes clear that the real problem for the US at Savo Island was the total lack of communication. It is breath taking to see the total confusion within the US forces. Ships did not announce they were under attack or that they had spotted enemy. They all seemed to think that everyone saw what they saw and everyone heard the same radio messages. If was as if no one ever studied the night actions at Jutland. Even within the ships vital information was not passed along to the Captain. The Commander of the southern force went to a conference but didn't make it clear who would command in his absence. The Commander of the northern force expected that there might be a night attack and put his ship in a higher state of readiness but didn't bother to tell the other ships in his command. There are more examples.
The USN didn't suffer such a grievous defeat due to superior Japanese torpedoes or superior Japanese optics or superior tactics. They lost because they were in total disarray due to a lack of effective communications. As Strother Martin said:

View: https://www.youtube.com/watch?v=V2f-MZ2HRHQ

All that may be true - at Savo island. But there were many other battles in the South Pacific. The long range of the type 93, as well as it's speed and large warhead, did actually turn out to matter, just as it certainly would have against the RN. I'll provide some examples tomorrow.

 

[BarnOwlLover]

Good stuff. It's funny how much of this stuff about the filters seems to be on the modeling forums, that is what I was finding too.

Yes i was aware that Aboukir was one of the depot bases. I had been under the impression that they had made a general transition away from the vokes type, but I guess by the time this was getting underway the war was already shifting north into Italy where the problems with dust were not as severe and I think they stopped using tropical filters altogether eventually.

And I guess they never brought this useful innovation over to the Pacific, but when you see the later model Sptifires (Mk VIII etc. ) in the Pacific Theater they don't seem to have the big vokes type filter housing.

That's because the IX/VIII and later Spitfires (including Griffon powered versions) had the filter integrated into the cowling as basically a extension of the supercharger intake. It basically looks like an elongated supercharger intake fairing. This was introduced with the Merlin 60 series switch over on the IX/VII/VIII. Why it wasn't applied to the single stage Merlin Spitfires, I don't know, given that the Mosquito got similar filters on their 20 series engines.

 

[ThomasP]

My understanding is that pretty much all the Mk VIII received the later Universal type Vokes filter. As mentioned above the Universal type had the ability to bypass the air filter. All later war-time Marks (except maybe the first few Mk IX Tropical?) were fitted with the Universal type Vokes filter, if they received air filters. The Seafire Mk I & II received the early Vokes filter when fitted (I think all the Mk IIC were so fitted), while the Seafire Mk III were all fitted with the Universal type.

Whoops, cross posted with BarnOwlLover.

AFAIK the only single-stage Merlin Spitfire to be fitted with the later Universal type of air filter was the Seafire Mk III.

 

[Shortround6]

Problem with the Type 93 torpedo was that it was seldom used as intended.
A few reasons for that.
1, actually detecting the enemy at 40,000 meters, or even 32,000 meters. Actual detection ranges were shorter most of the time.
2, the big fleet action never happened. The idea of firing hundreds of torpedoes into a large enemy formation (BBs in the middle, Cls around them, with DDs even further out) at very long range and then moving in to attack the reduced size fleet, may have worked or may not have worked.
All of the actual WW II engagements used both smaller numbers of ships on each side and smaller numbers of torpedoes. Sometimes dozens of torpedoes but not hundreds envisioned.
This affects several things, one is the torpedo density, they were not aiming at single ships but at the entire formation, so if the number of torpedoes per sq mile of ocean goes down the number of hits goes down. 2nd one is size of the formation, the formation covers less area making better aim more important, not say saying the Japanese were not skilled. They were very skilled, but firing torpedoes at ships that are at 30,000 meters and are running 24knts at 270 degrees and the Japanese think they are running at 22kts and steering 260 degrees on a short formation means less chance of getting hits. 3rd, a small, short formation it more likely change course quicker or more often. 4 heavy cruisers can (maybe won't) change course as much as a battlefleet of 8-12 battleships (top speed 21 kts) and all the associated cruisers and DDs.

the Japanese Type 93 torpedo was very effective as used in WW II, but it was not used as intended and the extreme range was something of an illusion.
However even having 2 to 3 times the range is a very large advantage. So is the speed at the closer ranges.

 

[Wild_Bill_Kelso]

Problem with the Type 93 torpedo was that it was seldom used as intended.
A few reasons for that.
1, actually detecting the enemy at 40,000 meters, or even 32,000 meters. Actual detection ranges were shorter most of the time.
2, the big fleet action never happened. The idea of firing hundreds of torpedoes into a large enemy formation (BBs in the middle, Cls around them, with DDs even further out) at very long range and then moving in to attack the reduced size fleet, may have worked or may not have worked.
All of the actual WW II engagements used both smaller numbers of ships on each side and smaller numbers of torpedoes. Sometimes dozens of torpedoes but not hundreds envisioned.
This affects several things, one is the torpedo density, they were not aiming at single ships but at the entire formation, so if the number of torpedoes per sq mile of ocean goes down the number of hits goes down. 2nd one is size of the formation, the formation covers less area making better aim more important, not say saying the Japanese were not skilled. They were very skilled, but firing torpedoes at ships that are at 30,000 meters and are running 24knts at 270 degrees and the Japanese think they are running at 22kts and steering 260 degrees on a short formation means less chance of getting hits. 3rd, a small, short formation it more likely change course quicker or more often. 4 heavy cruisers can (maybe won't) change course as much as a battlefleet of 8-12 battleships (top speed 21 kts) and all the associated cruisers and DDs.

the Japanese Type 93 torpedo was very effective as used in WW II, but it was not used as intended and the extreme range was something of an illusion.
However even having 2 to 3 times the range is a very large advantage. So is the speed at the closer ranges.

Yes, and I pointed this out at the outset when discussing the type 93. IIRC there were some battles where they were launched in the dozens or scores at about 13-15,000 yards but not necessarily at 30,000 typically. This also applies to the Allied torpedoes - theoretical max range of 10 or 15,000 yards often translated to a practical range of more like 5-8,000, in part due to their lower speed.

And they did not necessarily get a high hit ratio at 15,000 yards. But at those ranges they did hit some US ships which thought they were far enough away to be out of danger.

Also, while even the quite fast type 93 torpedoes (which I believe could do 50 kts at around that range) still didn't hit necessarily before the gunfire, when they did hit it caused severe damage and thus sometimes doubled or tripled the losses (in terms of sunk, crippled, or heavily damaged / out of commission ships) on the American side. Which therefore were not around for the next battle. And the same would have happened to the RN.

I.e. they launched torpedoes, then there was an exchange of gunfire, with some damage on both sides (a good amount of which though is typically inconclusive) and then the torpedoes hit. Maybe the battle ends after that or continues a bit more. But the torpedo hits were telling.


That type 93, and the bombs from SBDs, are two of the biggest reasons why they call that area iron bottom sound.


As far as torpedoes, one of the interesting air launched types was the Italian motobomba ones that would be dropped in the midst of an enemy fleet and drive in concentric circles until they hit something (or didn't)

 

[Wild_Bill_Kelso]

Ok so here are the 13 major surface actions of the early Pacific war, from Jan 1942 to August 1943. In cases where the range of the Japanese torpedoes played a factor, I put an asterix in red. This amounts to 5 of the 13.

Battle of Balkpapan
Jan 1942, Dutch East Indies
US destroyers caught Japanese invasion fleet by surprise at night, launched torpedoes but the torpedoes failed.
Result: 4 IJN transports sunk. US victory.

Battle of Badung Strait
Feb 1942 - Dutch East Indies near Bali
After an ineffectual exchange of gunfire from 3 allied (Dutch, English and US) cruisers and 7 destroyers, 4 Japanese destroyers launched torpedoes from ~ 1,000 yards.
Result: 2 Allied destroyers sunk (one was heavily damaged and later scuttled). Japanese victory.
Detailed account here

Battle of Java Sea *
Feb 1942, Dutch East Indies near Java
Large, 7 hour long daylight encounter between IJN force (2 x CA, 2 x CL, 14 x DD) and Dutch-American-British fleet (2 x CA, 3 x CL, 9 x DD). Both gunfire and torpedoes were exchanged, with the Japanese CL Naka starting the engagement with the launch of type 93 torpedoes. IJN launched three large spreads of torpedoes at ranges between 14,000 - 28,000 yards. One IJN destroyer launched from 6,500 yards. The range was beyond what the Allies thought was effective range, and they thought they were being attacked by submarines. Only the third wave, launched from 14,000 yards, scored hits, but the hits were telling.
During the battle the Japanese launched 152 type 93 torpedoes, mostly from long range, and got 3 hits. They also shot 1,619 8" shells and got 5 hits. The Allies shot a similar number of shells and got only one direct hit. Allied torpedoes made no hits.
Result: 2 Allied CL and 3 Destroyers sunk, 1 Japanese Destroyer damaged. Japanese victory.
Detailed account here

Battle of Sunda Strait
Feb 1942, Dutch East Indies near Java
Japanese vessel DD Harukaze launched nine type 93 torpedoes from 3,000 yards. Perth (CA) and Houston (CA) ultimately sunk.
Result: Japanese victory

Battle of Bawean island (aka "Second battle of the Java Sea")
March 1942, Dutch East Indies near Java
Japanese attacked crippled RN CA Exeter and two US destroyers. Initial exchange was with cruiser gunfire, then torpedoes at short range.
Result: All Allied vessels sunk. Japanese victory.

Battle of Savo Island *
August 1942 - Solomon Islands
First attack of the battle was as Chokai launched torpedoes at 17,000 yards at 01:30. Five minutes after that Chokai opened fire with 8" guns. Canberra was hit by twenty 8" shells and one torpedo - but it was an American one! Chicago was then hit by a torpedo. This may have been from Chokai.
Result: 4 Allied (US and Aus) cruisers sunk, other ships damaged. 2 Japanese cruisers damaged. Japanese victory.
Detailed account here

Battle of Cape Esperance
Oct 1942 - Solomons
USN detected Japanese with radar from the Helena. There was an exchange of gun and torpedo fire from short range. Some friendly fire on the US side. Damage was mostly by gunfire, but one US torpedo from Buchanan hit Furutaka and crippled her. Furutaka was also further damaged by her torpedoes catching fire.
Result: 1 Japanese CA sunk, 1 DD sunk, 1 CA heavily damaged. USN Victory

Naval Battle of Guadalcanal (first)
Nov 1942 - Solomons
Japanese and US fleet encountered each other at short range. Confused action with torpedoes and gunfire on both sides. Most US losses due to torpedoes.
Multiple Allied ships crippled, one Japanese Battle cruiser crippled and then sunk. Japanese Victory

Naval Battle of Guadalcanal (Second)
Nov 1942 - Solomons
Washington with the help of radar and visual sighting opens fire from 11,000 yards and sinks Kirishima. US destroyers hit by gunfire and torpedoes.
Result: Japanese battleship and one destroyer sunk, three US destroyers sunk, US Battleshp South Dakota damaged. USN victory

Battle of Tassafronga *
Nov 1942- Solomons
Eight Japanese destroyers vs 4 US heavy cruisers, 1 light cruiser, and 6 US destroyers. US commanders believed that a range of 12,000 yards was safely beyond torpedo range. Japanese destroyers launched torpedoes from 9 - 14,000 yards. US destroyers requested permission to launch torpedoes at 7,000 yards which is initially denied as being too far. US finally launched torpedeos at 5,000 yards. Gunfire from heavy cruisers opened up at ~ 9-10,000 yards. All Japanese damage was due to torpedoes.
Result: US gunfire sunk one IJN destroyer. One US CA sunk and 3 heavily damaged (blown off bows etc.). Japanese Victory.
Detailed account here

Battle of Komandorski Islands
March 1943 - Aleutians
Daylight surface battle with heavy cruisers on both sides, US had 2 CA and 2 CL, Japanese had one of each, both sides had 4 destroyers. Gunfire exchange at long range. Some hits with 6 inch guns. Most damage was by 8" guns. Japanese launched at least 30 torpedoes but all missed. US launched torpedoes from 10,000 yards but also missed.
Result: One USN CA heavily damaged, one IJN CA moderately damaged, but IJN fleet retreats. USN Victory.

Battle of Kula Gulf *
July 1943 - Solomons
Both Japanese and Americans had radar. Three Japanese DDs launch first volley of 14 torpedoes from 'long range' (Wikipedia says 20km). One hit US DD Strong. Wikipedia says this was the longest successful torpedo attack of WW2. USN was still not expecting torpedoes to travel this far. US ships open fire from 15km, sinking a Japanese destroyer. Helena was out of flashless powder, and was targeted by 16 torpedoes from Suzukaze and Tanikaze, being hit and sunk by at least two type 93 torpedoes. They took light damage from gunfire. Another Japanese DD was grounded and later abandoned.
Result: One USN CL sunk, 2 IJN DDs sunk. Japanese land some troops. Inconclusive.
Detailed account here The Wiki also has a lot on this one.

Battle of Kolombangara (aka Second Battle of Kula Gulf) *
July 1943 - Solomons
Small battle with three (US and New Zealand) light cruisers with 10 destroyers intercepting a 'Tokyo Express' force of one CL and 9 destroyers. Both US and Japanese launched torpedoes at roughly 10,000 yards, but the Japanese launched first and then turned away. US still thought Japanese torpedo range was about 10,000 yards. Both sides exchanged gunfire at 9,000 yards Spotting aircraft were being used to help sight in the rounds. US launched a second volley of torpedoes from 7,900 yards. Japanese light cruiser Jintsu was hit by gunfire and at least two US torpedoes, and sunk. New Zealand cruiser Leander was hit by a type 93 torpedo and badly damaged, as was DD Gwin which sunk.
Result: One US destroyer sunk, New Zealand cruiser badly damaged, 1 Japanese light cruiser sunk.
Detailed account here

Battle of Vella Gulf
August 1943 - Solomons
Japanese evaded 30 torpedoes from US PT boats (PT 109 is sunk in a collision). Four Japanese destroyers are then intercepted by six US destroyers which detect them with radar. US commander (Moosbrugger) disabled the magnetic detectors and set this torpedoes to run at 5 feet depth and 36 knots. With these modifications he trusted his torpedoes and decided to use them in preference to long range gunfire, against advice of his superior. He also had good radar. US destroyers fired 24 torpedoes at 6,300 yards. Only one Japanese destroyer returned fire.
Result: Three Japanese destroyers sunk. US victory.
Detailed account here

 

[SaparotRob]

Weren't there few more torpedo hits in the Battle of the Sunda Straight?

 

[Wild_Bill_Kelso]

Weren't there few more torpedo hits in the Battle of the Sunda Straight?

yes but torpedoes were fired at short range in that battle, as far as I could tell

 

[SaparotRob]

Hits on transports?

 

[Wild_Bill_Kelso]

Hits on transports?

Here is a detailed account of the battle at Sunda Strait

Battle of Sunda Strait 28 Feb. -- 1 March, 1942, by Vincent P. O'hara

Says Japanese opened hostilities when the Japanese destroyer Fubuki launched nine type 90 torpedoes (earlier and less effective type than the famous type 93) from about 3,000 yards. Then other Japanese destroyers arrived and launched 28 x type 93s but i couldn't figure out at what range, but there seemed to be a short range exchange of gunfire at this time. Japanese heavy cruisers then fired six torpedoes from 9,300 yards. A torpedo eventually hit Perth but it's unclear if from the CA or the DDs (probably at shorter range) but was then hit several more times. Then Mogami fired six type 93 at the Houston (set to run at 48 knots) and hit for or five times.

The Japanese lost a minelayer and 4 troopships, with a cruiser and 3 destroyers lightly damaged. As far as i can tell from the confusing account, these were sunk by gunfire probably from the Houston and / or Perth. I couldn't figure it out though.

 

[Wild_Bill_Kelso]

One thing I noticed reading through these, is that the long range gunfire from the destroyers (say 10 - 20,000 yards) and secondary guns (the 5" and 6" guns) rarely seemed to hit anything, and when they did hit at that range (usually from one or two shells) it often (not always) caused light damage. More telling hits were usually at around 5,000 yards or less (where they would get multiple direct hits).

It was pretty similar with the 8" guns from the heavy cruisers, in that they usually missed at long range, but the difference is even one 8" shell much more often caused serious damage. The 8" guns also had a bit longer range threshold where they started to get a lot more hits, like 8-10,000 yards. For example in the battle of Java Sea, one 8" shell from the Haguro, fired from about 20,000 yards, hit the RN heavy cruiser HMS Exeter, punched through a 4" gun mount and penetrating to her boilers where it exploded, severely damaging the ship and reducing her mobility. (This was after they lucked out being hit by a type 93 launched at 14,000 yards which was a dud and didn't go off!)

The battleships also missed at very long range like 20,000+ yards, but seemed a bit more accurate, and the hits from the 14" or larger guns seemed to usually sink or wreck their targets. Unless it was another battleship. Within say, 12-15,000 yards the battleships seemed to usually hit. Which is scary.

The type 93 torpedoes also clearly missed a lot at long range, though nowhere near as much as the guns did, and they usually sunk, crippled or severely damaged ships that they hit. For example, also during Java Sea, the Netherlands destroyer Kortenear was hit by a torpedo (also from the Haguro), and split it in half. Torpedoes wrought havoc even on much bigger ships. This is the heavy cruiser New Orleans after being hit by a type 93. It's really incredible to me that they could save ships with this much damage. Damage control was one of the main strengths of the USN though.

Inside say 10,000 yards the type 93s seemed to hit pretty often. For the US torpedoes the true effective range seemed to be closer to 5,000 - 8,000 yards.

Even at longer range, it was probably still worth it to launch. They launched 150 torpedoes in Java Sea from ranges between 14,000 - 20,000 yards, and only hit with 3, but those 3 hits basically took out (sank or crippled) enemy ships.


One other thing I've noticed, it seems like it was a lot easier to dodge the torpedoes during the daylight.

 

[SaparotRob]

Here is a detailed account of the battle at Sunda Strait
... Japanese heavy cruisers then fired six torpedoes from 9,300 yards...

The Japanese lost a minelayer and 4 troopships, with a cruiser and 3 destroyers lightly damaged. As far as i can tell from the confusing account, these were sunk by gunfire probably from the Houston and / or Perth. I couldn't figure it out though.

The Mogami was among these cruisers? These were Imperial Japanese Army troopships?

 

[Shortround6]

Battle of Balikpapan

I have put an account of this battle in the RN vs IJN thread.

 

[Frog]

Battle of Komandorski Islands
March 1943 - Aleutians
Daylight surface battle with heavy cruisers on both sides, US had 2 CA and 2 CL, Japanese had one of each, both sides had 4 destroyers. Gunfire exchange at long range. Some hits with 6 inch guns. Most damage was by 8" guns. Japanese launched at least 30 torpedoes but all missed. US launched torpedoes from 10,000 yards but also missed.
Result: One USN CA heavily damaged, one IJN CA moderately damaged, but IJN fleet retreats. USN Victory.

Nope, one US CA, one US CL, two IJN CA, two IJN CL, four destroyers for each side.

 

[Wild_Bill_Kelso]

Oh crap I posted all this in the wrong thread lol

 

[GrauGeist]

Battle of Sunda Strait
Feb 1942, Dutch East Indies near Java
Japanese vessel DD Harukaze launched nine type 93 torpedoes from 3,000 yards. Perth (CA) and Houston (CA) ultimately sunk.
Result: Japanese victory

I believe you forgot to mention IJN Mogami's spectacular torpedo attack.

A spread of six torpedoes resulted in the sinking of five ships:
4 IJA troop transports.
1 IJN minesweeper.

 

[Wild_Bill_Kelso]

I believe you forgot to mention IJN Mogami's spectacular torpedo attack.

A spread of six torpedoes resulted in the sinking of five ships:
4 IJA troop transports.
1 IJN minesweeper.

Ah, I missed that! damn! So that's what sunk the transports?

 

[SaparotRob]

Yup.

 

[GrauGeist]

Ah, I missed that! damn! So that's what sunk the transports?

Yes.

Including the transport with Lt. Gen. Imamura aboard.