ASW Stuff

[Shark7]

ORIGINAL: Buck Beach

ORIGINAL: JWE

Btw, Mr Palmer, we are vetting "every" combatant ship class and adjusting "everything" to the model: Sum[Num x Ammo] = (Irl Ammo)/2

While we are at it, we are getting the launcher distributions (# of slots, Num per slot) for everybody down pretty pat. Have good data on who did what to whom and when, so we'll tweak the Tacoma/Colony class while this is going on. The project does not seem to require any major adjustments, just a lotta little dinky tweaks here and there. Nothing especially noteworthy, except for ammo, but what's good for the IJN goose is certainly good for the Allied Gander.

While we are slicing and dicing the class slots, thought we might get the DD radars under better control, too.

Coming soon to a theater near you.

Probably not something appropriate for this thread but something to think about if your going to do some tinkering away. I have always thought there should be some way to account for those naval guns connected to a "fire control system". Maybe an accuracy penalty (separate devices) for the merchant ship's guns or other ships accordingly not having such systems.

Not smart enough to figure it out beyond the thought.

Buck

Perhaps reducing accuracy by 25-50%? Just a thought. [;)]

[JWE]

Babes has already tweaked the capabilities of depth charges vs diving depth of subs. This one is wrapped up very tightly with the algorithm, so I can’t say much about it. But, there is a bit of fuzzy math going on between the bottom of the drop depth of a DC and the diving depth of a sub, so it is “rational” to set the “drop depth” of a Type-2 at 375 feet, and the “diving depth” of a Balao or Tench at 410 feet, for example. Similarly, it is “rational” to set the “drop depth” of T-95 Mod 2s at 275 feet, while Gars, Tambors, Gatos can dive to 300 to 330 feet. That’s all I can say about it. Looked for hints to give, but just couldn’t find any that wouldn’t screw the pooch.

[oldman45]

After reading this page, I want to buy you all a drink

[Bradley7735]

ORIGINAL: oldman45

After reading this page, I want to buy you all a drink

+1. I'm thankful and impressed with the folks (mostly unknown to me I'm sure) who keep ironing out the little bumps in the game. And, I do stress 'little.'

[mike scholl 1]

ORIGINAL: Local Yokel

John, you are right to chide me for over-simplifying. And I take your point about the rate of increase in sequential hit probabilities. Nevertheless, the larger the number of weapons an ASW ship can put in the water on a single pass, surely the more effective its attack is likely to be?

Elsewhere I've touched upon IJN doctrine being the laying down of the biggest possible pattern on a CertSub, and the USNTMJ's report’s description of a 19-charge pattern for a kaibokan. It is with this in mind that I should like to find a way of imparting to the IJN E-class ships the benefit of their large number of throwers, provided this can be reconciled with the need not confer Wunderwaffe capability upon them.

Reality check, "Yokel". In 44 months of war, Japanese surface vessels sank 21 US Subs (confirmed). Four more were sunk by "unknown" sources. Even if you give two of these "unknowns" to Japanese surface forces, that still makes less than one sinking every two months by ALL Japanese surface vessels. The US DE England sank 6 Japanese subs in TWO WEEKS!

ASW Warfare is not about the number of depth charges you can throw over the side..., it's about finding and fixing the target sub and the accuracy with which the ASW weapons can be delivered on the target. Without the electronics and sound equipment to "fix" a target, the Japanese had to use a "heave and hope" approach..., and history shows that it was not a great success.

[Big B]

Hi all, interesting thread, but I have a sincere but innocent question on Japanese Escorts: What source is there for determining how many DC Throwers they carried and where?
I have Conway's All the World's Fighting Ships 1922-1946, and Jane's Fighting Ships WWII. Neither of those sources carry that info. Conway's only addresses the total number of DC's carried for Japanese DD's & Escorts (it does state numbers of DC racks for IJN DD's, and the locations and numbers of DC Racks and K-Gun Mounts for USN DD's & DE's ...but nothing on IJN Escorts)?

So I am curious as to the source for the details on IJN Escorts? Inquiring minds would like to know?

EDIT: OK - it looks like Online Sources will give you the Info [;)]

[Big B]

KAIBOKAN C and D
October 8, 2010 0 Comments
Link

It does appear they may be overpowered in the game, historical win/loss rate vs submarines shown below:
13 Escorts sunk by Submarines vs 4 Submarines sunk by these same Escorts:
Ships lost

CD-1, commissioned on February 19, 1944. CD-1 was sunk by B-25 bombers on April 6, 1945.

CD-3, commissioned on February 29, 1944. CD-3 was sunk by TF 38 carrier aircraft on January 9, 1945 at 27-10N, 121-45E.

CD-5, commissioned on March 19, 1944. CD-5 was sunk by carrier aircraft on September 9, being set afire and later blowing up and sinking at 15-30N, 119-50E.

CD-7, commissioned on March 10, 1944. CD-7 was torpedoed and sunk by USS Ray on November 14, 1944 at 17-46N, 117-57E.

CD-9, commissioned on March 28, 1944. CD-9 was torpedoed and sunk by USS Gato on January 12, 1945 at 32-43N, 125-37E.

CD-11, commissioned on April 5, 1944. CD-11 was damaged and had to be beached by B-25 bombers on November 10, 1944 at 10-51N, 124-32E.

CD-13, commissioned on April 26, 1944. CD-13 was torpedoed and sunk by USS Torsk on August 14, 1945, the day before the end of the war.

CD-15, commissioned on May 1, 1944. CD-15 was torpedoed and sunk by USS Raton on June 6, 1944.

CD-17, commissioned on May 7, 1944. CD-17 was torpedoed and damaged by USS Tilefish on July 18, 1944. CD-17 was sunk by carrier aircraft on January 12, 1945.

CD-19, commissioned on May 20, 1944. CD-19 was sunk by TF 38 carrier aircraft on January 12, 1945.

CD-21, commissioned on August 18, 1944. CD-21 was torpedoed and sunk by USS Seahorse on October 6, 1944.

CD-23, commissioned on October 29, 1944. CD-23 was sunk by carrier aircraft on January 12, 1945.

CD-25, commissioned on July 30, 1944. CD-25 was torpedoed and sunk by USS Springer on October 6, 1944.

CD-31, commissioned on October 13, 1944. CD-31 was torpedoed and sunk by USS Tirante on April 14, 1945.

CD-33, commissioned on October 13, 1944. CD-33 was sunk by carrier aircraft on March 28, 1945.

CD-35, commissioned on November 21, 1944. CD-35 was sunk by carrier aircraft on January 12, 1945.

CD-39, commissioned on November 9, 1944. CD-35 was sunk by B-25 "Mitchells" on August 7, 1945, the day the atomic bomb was dropped on Hiroshima.

CD-41, commissioned on November 26, 1944. CD-41 was torpedoed and sunk by USS Sea Owl on July 9, 1945.

CD-43, commissioned on September 10, 1944. CD-43 was sunk by carrier aircraft on January 12, 1945.

CD-47, commissioned on November 2, 1944. CD-47 was damaged by aircraft on three occasions, on January 29, February 15, and July 30, 1945. She was torpedoed and sunk by USS Torsk on August 14, 1945, the day before the end of the war.

CD-51, commissioned on October 29, 1944. She was sunk by TF 38 aircraft on January 12, 1945.

CD-53, completed on November 28, 1944. On February 7, 1945 She was torpedoed and sunk by USS Bergall.

CD-65, completed on February 13, 1945. She was sunk on July 14, 1945 by TF 38 carrier aircraft.

CD-69, completed on December 20, 1944. She was sunk on March 16, 1945 by B-25s.

CD-73, completed on April 5, 1945. On April 16, 1945, just eleven days after completion, she was torpedoed and sunk by USS Sunfish.

CD-75 , completed on April 12, 1945. She survived the war, but was torpedoed and damaged by Soviet submarine L12 on August 22, 1945. She was scuttled the next day.

CD-213, completed on February 12, 1945. On August 18, 1945, after the war ended, she sank after striking a mine.

CD-219, completed on January 25, 1945. She was sunk by TF 38 carrier aircraft on July 15, 1945 off Hakodate.

Successes

USS Growler was sunk on November 8, 1944 by CD-19 with Chiburi and destroyer Shigure.

USS Trigger was sunk on March 28, 1945 by CD-33 and CD-59 with Mikura.

USS Bonefish was sunk on June 19, 1945 by C Types CD-63, CD-75 and CD-207 with Okinawa and CD-158.

USS Salmon was rendered unfit for further service by damage from CD-33 and CD-29 with CD-22 on October 30, 1944.



The D Type class escort ships were a class of ships in the service of the Imperial Japanese Navy during World War II. The Japanese called them "D Type" coast defence ships, and they were the sixth class of Kaibokan (Kai = sea, ocean, Bo = defence, Kan = ship), a name used to denote a multi-purpose vessel.



The D Type, like the Ukuru-class and Mikura-class, were dedicated to the anti-aircraft and anti-submarine role.

[inqistor]

I do not understand this "ammo" part.
During all this years, I have played WITP/AE, I have seen maybe 3 times, that ship ran out of DC ammo. And I do not think it is actually possible for not dedicated ASW TF.
So, this larger ammo allowance, will only kick in, when there will be more than, maybe 3 ASW attacks during mission. And all those attacks would have to be made by THE SAME ship. Quite rare occurrence.
Otherwise those ships will be actually WEAKER, because they will have LESS DC launchers.


I have checked my current GC game, and I see this number of spent DC ammo for ships on-map:
1 2 3 3 7
all launchers have full complement of 8 ammo


Same game, but month earlier save:
1 1 2 3+1(ship have launchers in 3 slots, 2 actually show ammo used) 2 4(the only ship, which spent all ammo) 2+5 7
Ships which shows only ONE number have all their DC launchers in ONE slot.

So, that indicates, that on-average ship uses 1-3 points of ammo per ASW attack. It also seems, that with several slots more than ONE is firing. So, as long as there is AT LEAST 3 ammo, behaviour of ships will be identical during ASW combat, and only difference will be number of launchers (or their mounting points).

This is not actual test, but it will be easy to actually check, if someone want to set scenario. Just some SS with non-working torpedoes, and some ASW groups. It will be easy to count used ammo after each attack.

[el cid again]

I notice that in AE aircraft dedicated to hunting submarines do not carry ASW weapons.
They seem to rely on bombs. And to a lesser extent, on guns. Granted both are harmful
to submarines, still IRL all these aircraft ( and blimps ) carried DC - and sometimes no bombs
at all (a blimp typically only carried DC - and had a single nose .50 cal MG). In spite of how
UV and WITP worked, I was surprised to see this in AE.

Are these armament conventions correct in game terms? That is, does the air ASW model
ONLY permit a submarine to be attacked on the surface? In fact, submarines are much easier
to see from the air than from a ship - and the U-505 was captured because aircraft saw her
UNDERWATER and marked her position (by firing their MG at the position) so the ships knew
where to use their ASW weapons. Aircraft fitted with DC can drop - and often do not need
anything like the large patterns ships use - because they actually have a sense of where the
target is right now - where a ship is usually using old data - since it had to close the range
in order to attack.

Suppose a GAME aircraft were armed with DC - say a PBY. IF it spotted a submarine in code
terms, would the DC be "dropped" - and if so - would they do any harm to the target? Or are
DC hard coded as "ship weapons" - even specialized aircraft DC - and they will be ignored in a
submarine situation? IRL a DC need not hit a target to hurt it - and dropping near it is not a good
thing from the submarine point of view. But can we drop DC on submarines at all, even surfaced?
Can we treat them as a sort of "non AP bomb"?

IF this interpretation is correct, I propose to take a bomb device, give it a name as DC,
and value related to the way DC are rated (effect = weight in pounds I think, no penetration or perhaps
only a little) - so it looks like aircraft carry DC - and so the effects are not the same as for bomb hits
if they hit.

[Local Yokel]

Ah "Scholl"… no, on second thoughts I'll not respond to your vacuous rehearsal of the obvious, as it will only encourage you to descend to the personal abuse in which you engaged in the "SLC = 15K VP" thread.

@Big B: You can find quite detailed information about all the kaibokan classes in the monograph by Hans Lengerer and Tomoko Rehm-Takahara that was published in three parts in Warship Nos.30-33, republished by Conway in 1984 in Warship Volume VIII. Additional information is available at the combinedfleet website.

Your casualty list omitted CD-112, a D-gata class member that deliberately intercepted a torpedo fired by SS-220 Barb at JNR ferry Soya Maru whilst on passage between Wakkanai and Odamari (Karafuto) on 18 July 1945.

The Yamato Museum at Kure has a large collection of naval photographs which includes an extensive selection of kaibokan shots.

On the subject of radar fitting dates, I went through all the kaibokan TROMS so far published on the combinedfleet site. Unfortunately these give no information at all about the 'Type 22' (strictly, 222 GÔ dentan) fitting dates, and very little about 'Type 13' (13 GÔ dentan) fit dates.

Specific mention is made of the following fittings of Type 13 sets:

CD-37 April 1945 (C-gata class)
Hachijo October 1943 (Shimushu class)
Oki June 1944 (Etorofu class)

Fitting dates are also given for Ikuna, Habushi and Imami, but these all appear to have been part of the vessels’ final fitting out when new.

Since they were all tucked away on Hokkaido-Sea of Okhotsk assignments I am doubtful as to whether, aside from Hachijo, any of the four Shimushus ever received a Type 13 set.

Pictures of C- and D-gata escorts carrying Type 13 antennae seem to be very uncommon, and I have seen only one picture of a Mikura so fitted. Lengerer observes that Type 13 sets were fitted to Mikuras 'as of autumn 1944'.

Most Ukurus seem to have been photographed with Type 13 antenna, and Ikuna's receipt of such a set in the same month as her completion – October 1944 – suggests that in the game the class should be eligible to receive them from this date.

Unfortunately I have been unable to put a date to most photographs I have seen, so it would be unwise to read too much into the photographic evidence.

As to the 222 GÔ dentan, Lengerer states that from about June 1943 the Etorofu class ships began to be fitted with a modified foremast topped by a platform to carry this pattern of surface search set. The combinedfleet site class summary page says that the class was re-armed with a sensor suite that included these sets 'by August 1943' – perhaps this, with Lengerer's remarks, suggest August 1943 as a more appropriate date for the availability of such an upgrade for the Etorofus than the game's February 1944 date.

The combinedfleet site summary says that Mikura class ships were fitted Type 22 sets in 1944. Lengerer says that the Mikuras were equipped with Type 22s 'when completed'. FWIW I have yet to see a photograph of a Mikura class ship was not equipped with a Type 22 set, so I am inclined to agree with Lengerer. This would imply their inclusion in the initial equipment for the class at slot 1302.

The Ukuru, C-gata and D-gata kaibokan are all fitted with Type 22 sets as built, so no difficulty there.

Incidentally, I think there is a case for introduction of an 'intermediate' class between the Mikuras and the Ukurus. This should consist of a Mikura A/S weapons fit on an Ukuru hull, and would reflect the fact that nine vessels built at Hitachi's Sakurajima yard were outfitted with the Mikuras' depth charge armament (2 X Type 94 Y-guns plus 2 stern rails), but allocated to the Ukuru class. The ships concerned were Hiburi, Daito, Shonan, Kume, Ikuna, Shisaka, Sakito, Mokuti and Habuto. In fact, taking this further, the Mikura class depth charge set-up in both stock and BigBabes appears to me to be completely wrong, and should be toned down as described for the Hitachi ships.

[mike scholl 1]

ORIGINAL: Local Yokel

Ah "Scholl"… no, on second thoughts I'll not respond to your vacuous rehearsal of the obvious, as it will only encourage you to descend to the personal abuse in which you engaged in the "SLC = 15K VP" thread.

RIGHT! Wouldn't want any nasty old "Historical Realities" poking holes in your fantasies. [8|][8|][8|][>:]

[treespider]

ORIGINAL: mike scholl 1

ORIGINAL: Local Yokel

Ah "Scholl"… no, on second thoughts I'll not respond to your vacuous rehearsal of the obvious, as it will only encourage you to descend to the personal abuse in which you engaged in the "SLC = 15K VP" thread.

RIGHT! Wouldn't want any nasty old "Historical Realities" poking holes in your fantasies. [8|][8|][8|][>:]

To be fair Scholl the vast majority of the sinkings took place in 27 months (not 44) from 1/43 through 3/45.

Curious what the numbers would show if one were to compare ASW assets committed versus sinkings if one were to compare Pacific to Atlantic. for a similar time frame.


In other words the Germans lost circa 500 subs in 1943 and 44...but how many ASW assets were committed to the endeavor?

Versus the 40 some odd US subs lost to JApanese ASW assets.

I do not know the answer just curious what the ratios would be?

[oldman45]

Treespider - That would be an interesting bit of information to look at. Considering the Hunter-killer groups, LBA, and of course the convoy escorts themselves, I would be willing to go out on a limb and say the numbers would be two or three times higher than anything the Japanese mustered.

Inqistor - I went back and looked at some old saves and I found that my experienced ASW TF's would run out of DC's on 1 and sometimes 2 of the ships if they made multiple attacks which they usually did. This was in the late 1943 time period. Based on what has been written here, since the more experienced crews are acquiring the target more often they attack more often. I didn't bother to look at the Japanese sunk ship list to verify kills but these groups did infact claim more kills after their attacks.

Cid - I had the same thought the other day and have started working on a test to see if putting modified DC on a plane makes a difference. Not sure if it will work because of the game engine.

[JWE]

ORIGINAL: Local Yokel
Incidentally, I think there is a case for introduction of an 'intermediate' class between the Mikuras and the Ukurus. This should consist of a Mikura A/S weapons fit on an Ukuru hull, and would reflect the fact that nine vessels built at Hitachi's Sakurajima yard were outfitted with the Mikuras' depth charge armament (2 X Type 94 Y-guns plus 2 stern rails), but allocated to the Ukuru class. The ships concerned were Hiburi, Daito, Shonan, Kume, Ikuna, Shisaka, Sakito, Mokuti and Habuto. In fact, taking this further, the Mikura class depth charge set-up in both stock and BigBabes appears to me to be completely wrong, and should be toned down as described for the Hitachi ships.

Enterprise recon photo of Maizuru, June 14, 1945. Otori and Hyabusa at dockside, Sakura on mooring bouys, unidentified Ukuru (possibly Inagi) under way from dock. Can make out three Type-94 Y-thrower installations, and two chutes on the afterdeck and fantail of the Ukuru.

Next is Ikuna, October 1944, with three Type-94 Y-thrower installations, and chutes visible on the afterdeck. Next is Uku, 1944, with a “low profile” afterdeck looking very much like Type-3 launchers with DCs inserted.

Last is a set of Ukuru drawings, both referencing 1944, the top labeled ‘early’ (looking very much like Ikuna), the bottom labeled ‘late’ (looking very much like Uku).

[JWE]

Mikuras are much harder to dial in. Mikura and Miyake seem to have left the yards with two Type-94s, two rails, and sweep gear. The sweep gear was removed and a third Type-94 substituted “approximately” 1944. Only late war pics of a Mikura is of the Kurahashi, in the NTMJ appendices, but unfortunately do not cover the afterdeck very well. However, the text notes the NTMJ supervised her disarmament, including “removal of her 12 depth charge launchers”. Conways gives Nomi, as completed, with 12 Type-3s.

Possible that Mikura and Miyake started life with 2x T-94s (going to 3x almost immediately), Awaji and Yashiro (Hitachi built ships) started life with 3x T-94s, and Kurahashi, Nomi, Chiburi, and Kusagi (all Tsurumi built ships) had 12 T-3s. Trust the IJN to make life complicated.

This is plausible on many levels and also comports with all the different configurations reported in the literature. Original Mikuras specified 60 DCs, going immediately to 120. Drawings of IJN stern racks show 6 DCs and the ready rack for a T-94 held 6. 2 racks and 3 T-94s gives 30 DCs topside and ready and 30 more (one full reload) in a magazine in the fantail. Increasing loadout means magazine triples in size (30 to 90). Means rip up the deck and rebuild the aft compartments (if there was even room).

If you’re gonna do that, why not just stick in a T-3 installation which is configured (rack, room, and space) for 120 DCs

[ed] so think we'll keep Babes at 3r, 3l, shooting T-95 DCs and let them upgrade to the same 3r, 3l, but shooting T-2s with double the ammo. A better DC, twice the total 'drops', all things considered it works for me. Can't (actually won't) play around with a "class for every ship". Too much of a pain in the butt, and the present abstraction works very well. But there's tons of empty slots in the neighborhood, so finely dividing the Kaibokan types shouldn't give you too much heartburn. Have at it.

[mike scholl 1]

ORIGINAL: treespider

ORIGINAL: mike scholl 1

ORIGINAL: Local Yokel

Ah "Scholl"… no, on second thoughts I'll not respond to your vacuous rehearsal of the obvious, as it will only encourage you to descend to the personal abuse in which you engaged in the "SLC = 15K VP" thread.

RIGHT! Wouldn't want any nasty old "Historical Realities" poking holes in your fantasies. [8|][8|][8|][>:]

To be fair Scholl the vast majority of the sinkings took place in 27 months (not 44) from 1/43 through 3/45.

Curious what the numbers would show if one were to compare ASW assets committed versus sinkings if one were to compare Pacific to Atlantic. for a similar time frame.

Versus the 40 some odd US subs lost to ALL Japanese ASW assets.

I do not know the answer just curious what the ratios would be?

As usual, you make some fair points "Spider". Everybody's ASW results got better as the war continued. On the Allied side it seems to have been the result of more and better equipment, weaponry, and tactics. You don't get results like the ENGLAND's without a superb ASW suite and advanced weaponry like "hedgehog" and "mousetrap". For the Japanese it seems to have been just a case of more rather mediocre assets chasing more and bolder Allied subs. What improved equipment they did deploy seems to have been in the air rather than the surface units. If I recall correctly, there wasn't much improvement in results by their surface units between 43 and 45, but the air assets became more effective. Neither held a candle to the effectiveness of the Allies.

[mike scholl 1]

ORIGINAL: mike scholl 1

ORIGINAL: treespider

To be fair Scholl the vast majority of the sinkings took place in 27 months (not 44) from 1/43 through 3/45.

Curious what the numbers would show if one were to compare ASW assets committed versus sinkings if one were to compare Pacific to Atlantic. for a similar time frame.

Versus the 40 some odd US subs lost to ALL Japanese ASW assets.

I do not know the answer just curious what the ratios would be?

As usual, you make some fair points "Spider". Everybody's ASW results got better as the war continued. On the Allied side it seems to have been the result of more and better equipment, weaponry, and tactics. You don't get results like the ENGLAND's without a superb ASW suite and advanced weaponry like "hedgehog" and "mousetrap". For the Japanese it seems to have been just a case of more rather mediocre assets chasing more and bolder Allied subs. What improved equipment they did deploy seems to have been in the air rather than the surface units. If I recall correctly, there wasn't much improvement in results by their surface units between 43 and 45, but the air assets became more effective. Neither held a candle to the effectiveness of the Allies.

Did some additional checking, and it's wierder than I'd remembered. US sub losses involving Japanese surface units were:

1942 - 02
1943 - 09
1944 - 07
1945 - 04

So Japanese ASW ships actually became LESS effective between 1943 and 1045!

[Halsey]

bump...

[inqistor]

ORIGINAL: vettim89
when I ran my naked ASW tests last year I found that ASW value does play a big role in a TF's ability to detect a sub that starts the turn with a detection level of 0. I ran a test bed scenario where all other factors were the same (same ships, same crew exp, same environment). What I changed was the ASW value. I stared with 2 then went to 3 then 6. With each succeeding increase I saw a higher number of detections then prosecutions by the ASW TF. The test had the ASW TF's deliberately passing over the top of undetected subs. So while the ASW value does not have an effect on the combat once it starts, it does seem to have an affect on if there will be combat.

That is quite interesting. Have you put this in forum somewhere?
That would indicate, that detection is done separately by every device. I am not sure that there is in-game sonar, but this could be way to simulate it.

ORIGINAL: Buck Beach
I have always thought there should be some way to account for those naval guns connected to a "fire control system". Maybe an accuracy penalty (separate devices) for the merchant ship's guns or other ships accordingly not having such systems.

I was also thinking about it, and main problem I have found is:
How to simulate DAMAGE for fire control system?

ORIGINAL: el cid again

I notice that in AE aircraft dedicated to hunting submarines do not carry ASW weapons.
They seem to rely on bombs. And to a lesser extent, on guns. Granted both are harmful
to submarines, still IRL all these aircraft ( and blimps ) carried DC - and sometimes no bombs
at all

I was wondering what will happen, when you set "alternative weapon" (there is such field in editor for Device) as DC? Some planes use SAP bombs against ships, and GP bombs against ground targets. And I can see, that is because they are set in "alternative weapon" field. Is it possible to use different weapon in ASW mission?

ORIGINAL: Local Yokel
On the subject of radar fitting dates, I went through all the kaibokan TROMS so far published on the combinedfleet site. Unfortunately these give no information at all about the 'Type 22' (strictly, 222 GÔ dentan) fitting dates, and very little about 'Type 13' (13 GÔ dentan) fit dates.

I have somewhere USNavy report, about Japanese Radars, and it seems almost as private venture every time (you know, TOP SECRET!). It is almost like:
"We have this ship in port, and here are some spare parts, lets do some wiring", and after visit in another port they add another cables, and after third visit, VOILA! Working radar. So it does not seem to be any plan for upgrades.
Granted, report is based solely on interrogations after war.

ORIGINAL: oldman45
Inqistor - I went back and looked at some old saves and I found that my experienced ASW TF's would run out of DC's on 1 and sometimes 2 of the ships if they made multiple attacks which they usually did. This was in the late 1943 time period. Based on what has been written here, since the more experienced crews are acquiring the target more often they attack more often. I didn't bother to look at the Japanese sunk ship list to verify kills but these groups did infact claim more kills after their attacks.

Still, I have not see ANY advantage for ship with larger number of AMMO, in FIRST encounter (or even second). It will NOT have RtB earlier, but only if used in ASW TF. And I am not sure ASW ships live long enough, on average, to reload (one torpedo hit should sink them).

ORIGINAL: mike scholl 1
Did some additional checking, and it's wierder than I'd remembered. US sub losses involving Japanese surface units were:

1942 - 02
1943 - 09
1944 - 07
1945 - 04

So Japanese ASW ships actually became LESS effective between 1943 and 1045!

Probably were chased away/sunk by air forces, before they could actually engage submarine.

[JWE]

ORIGINAL: Local Yokel
On the subject of radar fitting dates, I went through all the kaibokan TROMS so far published on the combinedfleet site. Unfortunately these give no information at all about the 'Type 22' (strictly, 222 GÔ dentan) fitting dates, and very little about 'Type 13' (13 GÔ dentan) fit dates.

Wasn't quite what we were thinking of in terms of vetting. There's over 500 classes and dinking with intro dates for radar for each of them would be an impossible task. Maybe for a few, we can do it, but that's about it.

We're thinking more about radar device data. Did some analysis of some very well understood radar sets with respect to accuracy and resolution. One can get radial accuracy and distance resolution and in some cases altitude. Then adapted those values to game system requirements. Then ran specification comparisons against all the others and plotted the results.

Then found a decent place with all the base data for all nations, listed consistently. http://pwencycl.kgbudge.com/ (with 4 to 6 primary references for each and every radar). Ran our algorithm against their values and I will be dipped if they didn't plot out on the same curves, mostly. Okey dokey then. Modifying radar devices in accord with what we think is appropriate and what we have determined will fit within the game algorithm. Not huge, but a bit better and certainly smoother.