IJN DD availability chart

[ChuckBerger]

Here's the Destroyer availability chart. I have some ideas for improving the presentation, but here it is as a preliminary output! They're sorted by class, but I'd like to do a version sorted by date of loss as well.

[ChuckBerger]

And here's a chart showing some aggregate figures. The green is ships available for actual service, yellow is ships in refit or repair, and the light grey is ships under construction. Below the line are cumulative losses, by cause.

I'd also like to do a map showing the location of losses... so many plans

[JohnDillworth]

Considering that the U.S. torpedoes didn't work that well a lot of DD's were sunk by torpedoes

[ChuckBerger]

And a couple of observations:

1. Japan lost relatively few destroyers during the first months of the war - only 7 losses in the first 7 months of the war. But what is not often appreciated is that quite a few destroyers were seriously damaged, and it was not uncommon for destroyers to take 6-12 months to repair. The record is for Shiranui, which was out for a year and a half, but plenty of others were out of action for long periods of time.

2. Japan's losses during Guadalcanal were manageable, with 14 destroyers lost in the southern area from August 1942 to January 1943. However, Japan's shipyards were not keeping pace with repair requirements. By early 1943, the number of destroyers actually available for active service dipped below 60, and there were up to 20 destroyers in for long-term repair, aside from those in for shorter refits and repairs.

3. From early 1943 to Sep 1944, attrition of the destroyer fleet continued, especially with the loss of 19 destroyers total in the central and upper Solomons, and another 9 in and around PNG and New Britain. But the interesting thing is that during that whole period, the number of available destroyers held steady. From Nov 1942 to August 1944, the number of destroyers available for active service varied between between 55 and 65 ships, including 34-44 fleet boats. The reason is that, while losses continued, the shipyards were working through the backlog of heavily damaged ships and returning them to service.

(Of course, steady destroyer numbers wasn't going to win them the war, when the US was deploying hundreds of new ships!)

4. The real disaster was the Philippines - not just Leyte Gulf, but even more so the TA operations to reinforce Leyte, and various losses trying to get convoys to Luzon and damaged ships away from Luzon. The IJN lost 35 destroyers in the four months from Oct 1944 to Jan 1945, of which 29 were lost in and around the Philippines. That was more than half of their remaining destroyer force at the time. The number of fleet boats available for service went from 30 at the end of September 1944, to just 9 at the end of November.

5. In 1945, as the mass-produced Matsus continued to be completed in as little as five months, destroyer numbers actually increased a bit. But only 6 fleet boats were in fighting condition by the end of the war (Ushio, Hibiki, Yukikaze, and 3 Akizuki class completed in 1945 - Harutsuki, Natsuzuki, and Hanazuki - which never saw any real service)

6. Interesting as well is the shift in cause of loss. In 1942-43, it was US land-based air and surface battles that accounted for most losses, with a sprinkling of sub kills. In 1944, the US subs take over as the big IJN destroyer killer, and then the carrier aircraft go to town during the Philippines campaign, Okinawa and home island raids.

7. From Midway to Leyte Gulf, the IJN lost an average of 2.75 destroyers per month, and commissioned an average of 1.75 per month. So a net loss of 1 destroyer per month.

[ChuckBerger]

Finally, there are so many interesting stories about individual ships and their woes... here are a couple that I found most fascinating:

1) Matsu's suicidal charging of the US battle fleet, in order to buy time for the convoy it was escorting to escape. Every bit as heroic, if not quite as effective, as the US Destroyers at Samar. And it did allow some ships to get away.

2) Amatsukaze miraculously surviving the explosion of her forward magazines. Or at least half of her surviving - and returning to service as a half destroyer escort thingie, missing her entire bow third or so. Pictures here http://en.wikipedia.org/wiki/File:Japan ... e_1945.jpg

3) The loss of Yugure on 20 July 1943 off Kolombangara. She was sunk in a radar-assisted night attack by 6 TBF Avengers from Guadalcanal, carrying 2,000 lb bombs! CA Kumano was damaged during the same attack, and DD Kiyonami lost the next morning while rescuing survivors. I had no idea night air attacks were even possible at this stage of the war, aside from nuisance bombing and the black cat catalinas. An amazing event, does anybody know whether the US tried this tactic again to interdict the Tokyo Express runs? Or was it a one-off?

4) Kudos go of course to SS Harder for the amazing record of four IJN destroyers sunk. But the single best torpedo spead of the war must go to SS Growler, which with a single salvo sank DD Arare, crippled DD Shiranuhi and heavily damaged DD Kasumi. Kasumi was out of action for a year, and Shiranuhi for 18 months.

5) Oshio and Asashio beating back an attack by a far superior force of cruisers and destroyers at the Battle of Badoeng Strait. An astonishingly aggressive and successful battle, in which these two ships sank a dutch DD, damaged another DD and a light cruiser, and frustrated the efforts of an allied fleet of 3 cruisers and 7 destroyers to disrupt a Japanese landing force.

6) DD Yukikaze, which must be the luckiest ship of the war. It was involved in nearly every major battle, and survived all with never more than minor damage. Among others, survived Naval Battle of Guadalcanal, Battle of the Bismarck Sea, Leyte Gulf, and the final Ten-Go sortie with Yamato. Turned over to the Chinese, the ship wasn't scrapped until 1970!

What else...?

[Shark7]

On your point #4: It can be argued...

I-19 probably fired the single most devastating torpedo spread of the war. Of the 6 torpedoes fired, 3 hit CV Wasp, causing numerous munitions and fuel explosions which eventually lead to the abandoning and scuttling of the carrier; 1 hit BB North Carolina forcing it out of action for a month of repairs, and 1 torpedo hitting DD O'brien which caused enough structural damage to the ship to cause it to break apart a month later when sailing for the West Coast for repairs.

Fired 6 torpedoes and 5 hit.

[Leandros]

Fantastic work, Chuck!

Fred

[MBF]

Nice work Chuck ! Subs next ? (or did I miss that ??)

[bobdina]

Great stuff again. Thanks Chuck

[Buckrock]

ORIGINAL: ChuckBerger
3) The loss of Yugure on 20 July 1943 off Kolombangara. She was sunk in a radar-assisted night attack by 6 TBF Avengers from Guadalcanal, carrying 2,000 lb bombs! CA Kumano was damaged during the same attack, and DD Kiyonami lost the next morning while rescuing survivors. I had no idea night air attacks were even possible at this stage of the war, aside from nuisance bombing and the black cat catalinas. An amazing event, does anybody know whether the US tried this tactic again to interdict the Tokyo Express runs? Or was it a one-off?

During the Allied drive into the central Solomons in '43, TBFs were used for night shipping strikes against the Shortland Island anchorage (where they had some success) and offensive patrols against Tokyo Express runs (where they generally had little success beyond harrassment).

Their success on the night of 19/20th against Nishumura's surface force came about because of an "ideal" set-up. The relatively large Japanese task force was known to have left Rabaul on the 18th and was expected to be heading for the northern Solomons. A flight of 6 radar equipped TBFs had been readied for a night anti-shipping strike. A Black Cat PBY picked the enemy up as they headed for Vella LaVella. The strike was launched about an hour after the PBY contact. The enemy was found (by TBF radar at 9 miles) in the expected area. Bright moonlight allowed the TBFs to visually identify the enemy's dispositions while on approach and then manuever around his formation so as to place the enemy "up moon", eliminating the normal need for flares. When the TBFs swept in from "down moon" at very low altitude, they gained complete surprise, allowing the first bombs to be dropped before the enemy could react.

One key reason why the TBFs stuggled to repeat this night-time success against the standard Tokyo Express destroyer runs during the same period was that these runs were commonly conducted on nights of low or no moonlight, making TBF attempts to accurately deliver their bombs somewhat problematic. And if illumination flares were dropped first, surprise would be lost and the destroyers would normally then go into their well practiced evasion tactics.

Unfortunately for the Tokyo Express destroyers, this preference for operating on very dark nights also meant they were vulnerable to the radar-directed torpedo ambushes that USN destroyers began conducting in the second half of '43.

[Feltan]

ORIGINAL: ChuckBerger

What else...?

Did anyone else find it ironic that the IJN Kamikaze survived the war?

Regards,
Feltan

[Symon]

Way to go, Chuck. A very nice presentation.
Ciao John.

[warspite1]

ORIGINAL: ChuckBerger

Here's the Destroyer availability chart. I have some ideas for improving the presentation, but here it is as a preliminary output! They're sorted by class, but I'd like to do a version sorted by date of loss as well.

warspite1

[&o][&o]

[wdolson]

ORIGINAL: Buckrock

During the Allied drive into the central Solomons in '43, TBFs were used for night shipping strikes against the Shortland Island anchorage (where they had some success) and offensive patrols against Tokyo Express runs (where they generally had little success beyond harrassment).

Their success on the night of 19/20th against Nishumura's surface force came about because of an "ideal" set-up. The relatively large Japanese task force was known to have left Rabaul on the 18th and was expected to be heading for the northern Solomons. A flight of 6 radar equipped TBFs had been readied for a night anti-shipping strike. A Black Cat PBY picked the enemy up as they headed for Vella LaVella. The strike was launched about an hour after the PBY contact. The enemy was found (by TBF radar at 9 miles) in the expected area. Bright moonlight allowed the TBFs to visually identify the enemy's dispositions while on approach and then manuever around his formation so as to place the enemy "up moon", eliminating the normal need for flares. When the TBFs swept in from "down moon" at very low altitude, they gained complete surprise, allowing the first bombs to be dropped before the enemy could react.

One key reason why the TBFs stuggled to repeat this night-time success against the standard Tokyo Express destroyer runs during the same period was that these runs were commonly conducted on nights of low or no moonlight, making TBF attempts to accurately deliver their bombs somewhat problematic. And if illumination flares were dropped first, surprise would be lost and the destroyers would normally then go into their well practiced evasion tactics.

Unfortunately for the Tokyo Express destroyers, this preference for operating on very dark nights also meant they were vulnerable to the radar-directed torpedo ambushes that USN destroyers began conducting in the second half of '43.

VT-10 flying from the Enterprise in 1944 had a lot of success with mast height naval attacks and night. Most of their victims were merchant ships and auxiliaries though. Warships under full power are tougher to hit.

Bill

[jamesjohns]

Thank you! These are interesting charts, I plan to print them all out. I really like the second graph with active ships above the line and lost ships by cause below, very nicely done. [&o]

zJust curious what computer program you are using to make the charts?

[ChuckBerger]

I'm using Adobe Illustrator for the design. The posts here are limited to 500K, so the charts won't be print quality, esp. the DD chart which is much larger than the others. I'll look for a place to permanently post the AI files and a print-quality JPEG for each. Maybe Combined Fleet will agree to post them...

Subs are next. The chart will show when each was on war patrol, transport mission, training duties, or in port/transit. And also all significant attacks by each, and their victories, and a chart of losses like the DD chart. Fascinating stuff, I've never delved into the IJN submarine fleet or doctrine before.

[rustysi]

5) Oshio and Asashio beating back an attack by a far superior force of cruisers and destroyers at the Battle of Badoeng Strait. An astonishingly aggressive and successful battle, in which these two ships sank a dutch DD, damaged another DD and a light cruiser, and frustrated the efforts of an allied fleet of 3 cruisers and 7 destroyers to disrupt a Japanese landing force.

Yeah, this one was more of an Allied cock-up than a Japanese success. The Japanese were already done landing and were getting ready to withdraw. The Allied forces came in badly separated. The Dutch laid a smoke screen which inadvertently blocked the US destroyers. Et alia ad nauseam.