Taiyo class carriers.

[Wilhelm_Klave]

I was wondering about the class. I heard that later in the war they were used in anti-submarine patrol roles, but I had trouble confirming that.

Does anyone know what kinds of airplanes did they operate?
What was their initial 1941 role and composition of the carrier air wing? I know they were assigned to the 4th carrier division (togeatehr with shoho).
Was slow speed the only reason why there were used almost exclusively in the airplane transport roles, or was their short flight deck an issue?

[Sewer King]

From the World War II Database, a capsule history of the Taiyo-class escort carriers also cites their layout below decks -- due to their origin as passenger liners.

Their flight decks lacked handling gear, further limiting their combat use in fleet air operations.

(A.J. Watts old book Japanese Warships of World War II (originally UK, Ian Allen Ltd, 1966; US, Doubleday & Co Inc), pages 52-55)

I would expect that their range of only 6500 nmi at 18 knots was another limitation, seen against their 17830 tons standard displacement.

Compare to the Chiyoda-class, with a range of over 11000 nmi at 18 knots and only 11190 tons standard. They embarked 30 aircraft compared to Taiyo's 27.

(figures cited from Jentschura, Hansgeorg et al. Warships of the Imperial Japanese Navy 1869-1945 (translated from original German; Arms & Armour Press, 1977), pages 55-59)

-- Alan

[ijnfleetadmiral]

The Taiyos were mainly used as convoy escorts. IIRC they mainly carried Nakajima B5N Kates.

-Matt

[Ironmachine]

I heard that later in the war they were used in anti-submarine patrol roles, but I had trouble confirming that.

Not much, but:

23 May 1944:
At 0700, NOSHIRO MARU departs Singapore in fast convoy HI-62 consisting of transports KINUGASA, NISSHO, TAMATSU and TEIRITSU (ex-French LeCONTE de LISLE) MARUs and tankers OTORISAN, SARAWAK and NICHINAN MARUs escorted by escort carrier TAIYO that provides antisubmarine air cover and kaibokans SADO, KURAHASHI, CD-5, CD-7 and CD-13.
[...]
1 June 1944:
At 0400, HI-62 departs Manila. TAIYO continues to provide antisubmarine air cover

http://www.combinedfleet.com/Noshiro_t.htm

Regarding the aircraft

The designed aircraft mix for these ships was 21 fighters and nine attack aircraft. However, when they were assigned to the Grand Escort Command, only B5Ns were carried.

From Osprey's Imperial Japanese Navy Aircraft Carriers 1921-45 (New Vanguard 109)

[hisashi]

CV Taiyo was used for aircraft transporter until 1943. In early days, she had a small aircraft group of its own, an unknown number of A5M Claude and D1A2 Susie for CAP and patrol.
In Oct 1942, when she went to dock for repair, this group was disbanded. In Sep 1943 Taiyo was heavily damaged by torpedo from submarine and it was Apr 1944 she came back.
Then (The combined fleet HQ gave up replenishing southern bases by poorly escorted slow auxiliary CVs? They finally realized they must spend more resource for sea lane escort? Detailed decision remains unknown) Taiyo was passed to sea escort HQ. In Apr 1944, 12 B5N Kate, 931th NAG.

931th NAG was raised in Feb 1944 from local (ground) air group personnels and planes after CV Taiyo, Unyo, Kaiyo and Shinyo moved to sea escort HQ in Dec 1943 (note that many of them were still under repair). It had 48 Kate as an authorized strength and 4 teams of 12 Kate was attached to CV (now CVE?) when they departed and some of them took rest on the rotation. After Hi-86 convoy failed, they became a ground-based anti-sub patrol/attack group. In the battle of Okinawa they fought as torpedo attacker group (not Kamikaze) on newly issued B6N Jill(Apr 1945). 12 Aug 1945 one of four aircrafts from 931th damaged USS Pennsylvania.

Source:Japanese Wikipedia
http://ja.wikipedia.org/wiki/%E5%A4%A7% ... A%E6%AF%8D)
http://ja.wikipedia.org/wiki/%E7%AC%AC% ... A%E9%9A%8A

[Wilhelm_Klave]

Thanks guys, much appreciated.

I know they used A5M Clauseds on older carriers in 1941 and early 42, but the D1A2 Susie in a CAG is a suprise to me.

[Eugen Pinak]

Their flight decks lacked handling gear, further limiting their combat use in fleet air operations.

No - they had full landing equipment.

(A.J. Watts old book Japanese Warships of World War II (originally UK, Ian Allen Ltd, 1966; US, Doubleday & Co Inc), pages 52-55)

I would expect that their range of only 6500 nmi at 18 knots was another limitation, seen against their 17830 tons standard displacement.

They had range of 8500 nm at 18 knots.

Compare to the Chiyoda-class, with a range of over 11000 nmi at 18 knots and only 11190 tons standard. They embarked 30 aircraft compared to Taiyo's 27.

Due to their diesels "Chitose" class had, IIRC, the longest range of all IJN major surface combatants (only "Mizuho" and "Nissin" probably were better in this respect).

CV Taiyo was used for aircraft transporter until 1943. In early days, she had a small aircraft group of its own, an unknown number of A5M Claude and D1A2 Susie for CAP and patrol.

Mention, that D1A2 were used aboard carriers in Pacific war is new to me - thank you for the information.

[Sewer King]

I did have some uncertainty about Watts’ figures – that is why I noted his book as an old one. Maybe I should have made my doubt more clear. What is the source for Taiyo’s 8500nmi range?

:Their flight decks lacked handling gear, further limiting their combat use in fleet air operations.
[A.J. Watts old book Japanese Warships of World War II (originally UK, Ian Allen Ltd, 1966; US, Doubleday & Co Inc), pages 52-55)

No - they had full landing equipment.

World War II Database's entry for Taiyo:

. . . After being launched at Nagasaki, Japan, [Taiyo] sailed to Sasebo, Japan for final fitting and conversion between 1 May and 31 Aug 1941; she was to become an escort carrier with no island, no catapults, nor arresting gear.

Was this sort of aircraft handling gear added during her later refits?

I would expect that their range of only 6500 nmi at 18 knots was another limitation, seen against their 17830 tons standard displacement.

They had range of 8500 nm at 18 knots

The same entry repeats the 6500 nmi figure, although combinedfleet.com gives a general figure of 20,000 tons displacement and 21 knots.

I understand if some long-standard sources can have some information later found wrong. Authors Parschall and Tully at combinedfleet.com make note of error in Watts’ book. They have made their name we-examining long-standing accounts of battle, not only Midway. Jentschura is wide-ranging and comprehensive, but almost as old as Watts.

What published technical histories or sources of that kind are more authoritative now, whether for Taiyo or any other IJN ship class? Would they be in Japanese?

. . . In early days, Taiyo had a small aircraft group of its own, an unknown number of A5M Claude and D1A2 Susie for CAP and patrol.

This seems a natural parallel to the F4F WIldcats gone from fleet carriers to escort carriers.

But it is not clear whether Taiyo actually ever embarked A5M CLAUDE and D1A SUSIE for her early air group. This is apart from being able to "work up" as a group. Could they have been only assigned to the carrier -- but never put to sea with her, before she went to the aircraft transport role?

-- Alan

[hisashi]

> she was to become an escort carrier with no island, no catapults, nor arresting gear.

No island, no catapults (it limitted their choice of aircrafts), but they had arresting wire. But sometimes on aircraft transport mission wire was removed and they loaded aircrafts even on the flight deck.

>But it is not clear whether Taiyo actually ever embarked A5M CLAUDE and D1A SUSIE for her early air group.

Japanese Wikipedia quotes a pilot's recall. They actually made patrol flights from Taiyo (no mention about combat scores... perhaps none).

[Sewer King]

Thanks Hisashi, that makes it all clear.

I did think to try machine-translation of the Wiki page you gave, but am not confident in my own ability. Also, I will review your earlier cautions about their use, and the labor of Japanese translation.

The duty and arrangements of aircraft transport carriers is known, but not so widely covered in technical detail. This seems true even of the US Navy, where some of the many wartime escort carriers were put into that role postwar (their designation CVE changed to AVT, for auxiliary aviation transport).

-- Alan

[hisashi]

In general, having faster merchant fleet rewards much for the navy/government in wartime. Freighters have better chance to survive from any kind of peril. On the other hand, expensive high-power engine incur more fuel cost and construction cost in peacetime. Businessmen and authorities seek for a compromise in any country.
United States Maritime Commission
http://en.wikipedia.org/wiki/United_Sta ... Commission
It seems that IJN intended to use all converted CVs as fleet carriers. But their engine was too weak to catch up with fleets. Only Junyo and Hiyo were originally extra-high-speed passenger ship (of the day) and tolerable to IJN. AFTER all was planned and began, IJN noticed that replenishing aircrafts to isles base, including IJA's, was a great job. So they used Taiyo class and some similar converted CVs as aircrafts transporter.

[Eugen Pinak]

What is the source for Taiyo’s 8500nmi range?

Fukui "Nippon kubo monogatari", p.443.

. . . After being launched at Nagasaki, Japan, [Taiyo] sailed to Sasebo, Japan for final fitting and conversion between 1 May and 31 Aug 1941; she was to become an escort carrier with no island, no catapults, nor arresting gear.

Was this sort of aircraft handling gear added during her later refits?

The article you've quoted already contradicts itself - she could either a) become escort carrier (which demanded arresting gear), or b) become transport (which doesn't demand arresting gear).

What published technical histories or sources of that kind are more authoritative now, whether for Taiyo or any other IJN ship class? Would they be in Japanese?

In English you can search for works by Lacroix & Wells, Dullin & Gartzke, Lengerer, Ahlberg, Sakaida. If you can read Russian, you can read mine and Sidorenko book on medium-sized IJN CVs. If you can read Polish, I can say some good words about works by Kopacz and translated works of Lengerer.
And yes - there are a lot of technical histories in Japanese, from cheap and often worthless paperbacks to multi-volume works on some very obscure topics.

But it is not clear whether Taiyo actually ever embarked A5M CLAUDE and D1A SUSIE for her early air group. This is apart from being able to "work up" as a group. Could they have been only assigned to the carrier -- but never put to sea with her, before she went to the aircraft transport role

She certainly had operational AG aboard in summer 1942.

[hisashi]

That is, in early transport missions, Taiyo used only inner space for transported aircraft and kept the deck ready for a sorty by her own small AG. Moved aircraft was mainly Zeke. Nearby destination isle Zeke took off by themselves and landed to the destination. This operation did not need crane facility in the destination.
Later they put her AG off and used all inner space and space on deck, removing arresting wire, and destination must be a port with crane.

[Sewer King]

Thanks Eugen! Unfortunately I can neither reach or read Polish or Russian sources, but from my very limited viewpoint it is good to know that better ones are there. For other audiences it is unfortunate that English-language sources are not up to the same accuracy..

Occasionally I see a few military-technical books in Polish, but they tend to be are air- and ground-related (and European-oriented) rather than naval.

However, it seems to follow that these better books refer to the best original Japanese sources. Until I came to this Forum and section, I did not even know of Polish military scholarship on the IJA and iJN. This was introduced to me not by books, but by various knowledgeable members such as yourself. To a faraway newcomer, similar good scholarship in Russian might be expected because of history of Russo-Japanese conflict.

My own favorite thread about “Food Rations in the Japanese Forces” is much indebted to work by Dr. Katarzyna J. Cwiertka, who has studied Japanese language and history in Poland, Japan, and the Netherlands. In Poland is there a wider standing interest and study of Japan in general, beyond the military?

Whatever the mistakes, I could only find what seemed the better on-line sources for their affiliation. It would probably take some time to correct, even with likely cooperation.

It seems the US Naval Institute Press would look to updating its backlist of IJN technical titles, but I have not seen their recent catalogs. And so, apart from Linton and Wells, its authors would make use of these more accurate works.

A while back I borrowed Linton and Wells’ Japanese Cruisers of the Pacific War but forgot about that, not having seen it since. Once I had heard a rumor that the authors were considering a similar book about IJN destroyers -- a considerable job. The Fukui book sounds in this same class, if only for its length.

Bibliography about the Yamato-class battleships is fairly extensive, well-illustrated, and much translated. It is the interest in those near-legendary ships that led to good and readily-available books about them. But even half as much coverage for other IJN ship classes and types would be good to see.

-- Alan

[hisashi]

Janusz Skulski's drawings on Yamato was translated to Japanese and we are very impressed.

Japanese Embassy in Poland prepared a page how Poland had good relationship with Japan. On military issue, Józef Piłsudski, the leader of anti-Russian movement in Poland, proposed Polish POWs be treated better than Russians in Russo-Japanese War in exchange for their activity in Poland. Japan did so and it affected the image to Japan in Poland. Also in Siberia Intervention, Japan sent 765 Polish orphans who lost their parents in Siberia to Poland.
http://www.pl.emb-japan.go.jp/kultura/j ... pizody.htm
http://en.wikipedia.org/wiki/J%C3%B3zef_Pi%C5%82sudski