SUBSIM Radio Room Forums

SUBSIM Radio Room Forums (https://www.subsim.com/radioroom/index.php)
-   Silent Hunter 4: Wolves of the Pacific (https://www.subsim.com/radioroom/forumdisplay.php?f=202)
-   -   Info on japanese convoy's? (https://www.subsim.com/radioroom/showthread.php?t=94232)

Ducimus 06-08-06 08:04 PM

Info on japanese convoy's?
 
Anyone have some good info on what a typical japanese convoy consisted of?

DeepSix 06-08-06 08:56 PM

The first place I'd look for definitive answers would be Blair's Silent Victory. One thing I'm pretty sure the Japanese did not have lots of was huge convoys. IIRC, most of the time they sent stuff along in small batches; they only used massive convoys on a few occasions early war. I'm hesitant to go much further as far as what was "typical" - that changed some as the war went on - or throw out exact numbers because I'm going on memory. But as a ballpark start I would say that most of the time Japanese convoys consisted of less than a dozen ships and probably less than 10, and might include 2-4 small to medium sized freighters and/or tankers, plus an occasional monster. Escorts might number 3 or 4; IIRC the Japanese seemed to like putting 1 escort leading, 1 on either beam, and sometimes 1 in the rear. Of course, if it was a really important convoy there might be five or six escorts....

Hope you get some more precise info (and corrections) from other posters; just thought I'd throw that up as a start.:)

andy_311 06-09-06 05:26 AM

Don't know if this is any good to you.
www.afa.org/magazine/Aug1996/0896victory.asp

Red Devil 06-09-06 06:36 AM

Saw a large(ish) convoy recently with a carrier in the middle. It has 6 or 7 escorts, two lead, two beam and two rear, I think there was another according to sonar but did not spot it. The two rear were wide almost behind beam escorts. Strange thing is, I got the carrier and the escorts sailed on.

Threadfin 06-09-06 09:42 AM

I think Deep Six is spot on. I would add that the Japanese made extensive use of aerial escorts. Surface escorts might be destroyers, subchasers, frigates, minelayers, or other types of craft. It was also common that the Japanese would escort locally. That is, they would provide escorts through 'dangerous' areas, and a different group of escorts would pick them up further along.

Donner 06-09-06 10:55 AM

According to Mark Parillo's book, "The Japanese Merchant Marine in World War II"--ISBN 1557506779, Japanese convoys averaged about 5 ships in 1943. Any convoy consisting of 10 to 15 ships was considered "unmanageable."

I have a translated copy of S. Komamiya's Wartime Transportation Convoys History on a CD. A fellow submarine researcher gave me this last year. It is an indespensable document (nearly 500 pages total in 3 files of MS Word) if you are interested in the subject. I am unsure who holds the copyright (if any) on this translation.

Komimaya's work contains the following (where available): depature/arrival times, merchant ship names, escorting warship names, and a brief and sometimes detailed account of the convoys journey...including which particular Allied submarine (or ship) inflicted the losses. There also on index to locate US submarines involved in attacks.

A few sample listings:

Quote:

About dawn.
17th. March, 1942.
From: Hakata Bay, northern Kyushu.
21st. March, 1942.
To: Bako, Pescadores Islands.
Yubae Maru, Montreal Maru, Samaran Maru, Hanan Maru (4).
Auxiliary minelayer Kahoku Maru, destroyer Minekaze (2).
After safe arrival at Bako, Yubae Maru left bound for the Philippine Islands with an independent garrison force onboard. The other three headed for Singapore with replacement soldiers for the 18th. Infantry Division
Quote:

1200.
7th. May, 1942.
From: Mutsure, northern Kyushu.
To: Singapore.
No. 109
Taiyo Maru, Mikage Maru, Dover Maru, Ryusei Maru, Yoshino Maru (5).
Auxiliary gunboat Peking Maru (1).
At about 1945 on the 8th. May while at position 30.45N 127.40E off south‑west Kyushu Taiyo Maru was torpedoed by the U.S.S. Grenadier.
The submarine found convoy No. 109 and decided it consisted of six freighters and with her distinctive silhouette, the Taiyo Maru. Four torpedoes were fired for two claimed hits.



At the time lookouts on Taiyo Maru reported sighting a twinkling blue object astern to starboard, possibly this was from one of two magnetic torpedoes set to run under the ship, at the same time another torpedo exploded on her port side stern. The impact instantly destroyed Taiyo maru's communication facilities, it also caused her compass to be blown off.
The second missile struck home in No. 2 hold on the same side, about 150 tons of calcium carbide there caught fire and a cargo of hand‑grenades erupted in a series of explosions.
A few seconds later a third torpedo hit in the front part of No. 2 sealed the ship's fate for huge fires took hold. However as the submarine claimed only two hits possibly this so‑called third hit was actually an onboard explosion.
Meanwhile Peking Maru replied with a string of depth‑charges, close but Grenadier remained undamaged. The submarine later reported that she was attacked by "destroyers" afterwards, a total of thirty‑six were dropped over a period of four hours.
After the torpedoing there was chaos inside the maru, quickly the eighteen lifeboats carried were prepared for launching, some if not all of these crowded craft by 2020 were starting to leave the ship. By now water was up to C deck and a list of about 36 degrees had developed, consequently all hands were ordered off.
By 2035 Taiyo Maru's list because of the amount of water taken in had corrected itself but her bow had been thrust into the sea, finally the maru's stern rose vertically into the sky and by 2040 she was gone.
The weather was poor that evening and many of the evacuees were left struggling in the sea, consequently fatigue and the icy waters took their toll. Also some of the lifeboats capsized in the rough conditions adding to the casualties.
This large 14,457 ton ship owned by the Nippon Yusen Kaisha line was carrying 1044 passengers, 263 crew and four gunners, a total of 1311, 770 lost their lives.
However another report states that of the 1044 passengers, 660 lost their lives, of her crew of 263, 157 died representing a total of 817 casualties!
Her cargo consisted of the above‑mentioned calcium carbide, some shells, hand‑grenades and other ammunition plus baggage representing a total of 2300 tons.
Amongst the passengers were a large number of technicians, and people charged with the economic development of the newly captured territories in the southern area, many lost their lives.
The Japanese at the time were well aware that Taiyo Maru was a prime target for enemy submarines, afterwards they fully recognized the mistake of spending this 14 knot ship with a 9.5 knot convoy. Also because of the rough conditions the convoy was traveling a few knots less than the designated speed.
The rest of convoy No. 109 went onward and after making calls at Mako and Cape St. Jacques, arrived at Singapore on the 7th. of June, 1942.

Quote:

0700.
18th. August, 1943.
From: Palau.
0700.
28th. August, 1943.
To: Ujina, West Inland Sea (or possible Moji, northern Kyushu.)
FU‑806.
Taifuku Maru, Hozugawa Maru, Mexico Maru, Toyokawa Maru, Toun Maru, Kayo Maru (6).
Minesweeper No. 17, Minelayer Yurishima, auxiliary minesweepers No. 7, Tama Maru, No. 6 Tama Maru (4).
Late on the night of the 22nd. at position 21.50N 137.52E, Toun Maru was hit aft on the port side by a torpedo. Four missiles were seen approaching, one struck her coal bunker on the port side, luckily as it was a dud damage was slight.
The culprit was the U.S.S. Pike, the submarine fired two torpedoes each at two targets for one claimed hit and damage, no depth‑charge counter‑attack is recorded.
On the 23rd. at 1805 position 24.08N 137.37E Toun Maru was attacked again, the maru avoided the missiles. Again the attacker was the Pike,
the submarine fired four torpedoes for one claimed hit and damage. The submarine counted five depth‑charges but remained undamaged.
At 0530 on the 26th. Mexico Maru reported torpedo tracks approaching from forward, the escorts immediately opened fire, then four deep running torpedoes passed underneath one of the escorts.
The submarine was the U.S.S. Whale, she fired at both the escorts, three torpedoes at one and one at the other for no claimed hits. The escorts dropped five depth‑charges, Whale incurred slight damage.



At 0258 on the 27th. Taifuku Maru was torpedoed from 60 degrees off the port side by the U.S.S. Pollack. An attempt was made to turn her rudder, then a torpedo passed across her bow, then two passed under the No. 2 hold and her bridge, the remaining pair hit No. 3 and No. 4 holds. A terrible tremor ran through the ship, inside all the lights went out, rudder troubles occurred and all facilities on deck were destroyed. As the ship was obviously sinking it was quickly abandoned. A few minutes later her stern sank into the sea and at 0311 Taifuku Maru's bow rose into the air and she sank at position 32.28N 132.23E, 30 kilometers south‑west of Tosa, Okinoshima.
This ship was a victim of the U.S.S. Pollack, the submarine fired four torpedoes at a cargo ship and two at a "destroyer" for just one claimed hit on the former for damage. The escorts dropped seven depth‑charges but Pollack remained undamaged.
Taifuku Maru was a 3520 ton ship owned by the Nippon Yusen Kaisha Line, at the time she was carrying 160 passengers and the ashes of 137 dead, about fourteen men lost their lives.

Threadfin 06-09-06 11:52 AM

Outstanding stuff Donner, thanks for posting it. Would love to read more. I did a google but could find no info on where to obtain a copy. I'm always on the lookout for info and accounts from the Japanese side, which are not easy to find. A book like Silent Victory gives great detail from the US side, would be great to have the other side too (like in Fluckey's book, where he often gives info from the Japanese perspective on the targets he attacked)

However, while googling your thing I came across this, about the sinking of Arisan Maru. This was convoy MA-TA-30 (Manilla-Takao?) with 12 marus and 5 escorts.

www.gwdow.net/pdffiles/arisani.pdf

Sailor Steve 06-09-06 12:08 PM

Advanced Book Exchange has it, but for more than I can currently afford.
http://www.abebooks.com/servlet/Sear...557506779&x=49

Important question concerning SHIV: does the book contain a list of Japanese merchant names?

And thanks Donner, for sharing this wonderful find with us.

DeepSix 06-09-06 12:09 PM

Pop the ISBN number into the Amazon search bar; I got three hits, priced from $50-75 a copy (too bad; I'll have to wait a little longer before buying). I saw this title mentioned not too long ago in another thread but managed to forget about it; great info.:up:

Donner 06-09-06 12:25 PM

Parillo's book does not have a listing of Japanese merchants. :cry:

I should have made things more clear in my posting. The excerpts are from S. Komimaya's Wartime Transportation Convoys History which I have in MS Word format on CD. As I said, I was given this by another researcher last year.

The document is broken into 3 files of approximately 1.08 megs each. One is a tad bigger. So it totals out to about 3.33 megs.

Anyone interested in Komimaya's work can PM me for more info. :ping:

andy_311 06-09-06 08:06 PM

Quote:

Originally Posted by Red Devil
Saw a large(ish) convoy recently with a carrier in the middle. It has 6 or 7 escorts, two lead, two beam and two rear, I think there was another according to sonar but did not spot it. The two rear were wide almost behind beam escorts. Strange thing is, I got the carrier and the escorts sailed on.

In the Pacific ocean in sh3 I doubt it?

DeepSix 06-09-06 08:49 PM

Quote:

Originally Posted by Donner
...The excerpts are from S. Komimaya's Wartime Transportation Convoys History which I have in MS Word format on CD. As I said, I was given this by another researcher last year.
...

This is an amazing read. Lists number and names of marus and escorts in scores of Japanese convoys, ports of departure and arrival, sailing times, even mentions some of the subs encountered (by name) along the way.

Thanks, Donner, for sharing it with us.:up:

Crash Dive 07-14-06 05:59 PM

Quote:

Originally Posted by andy_311
Quote:

Originally Posted by Red Devil
Saw a large(ish) convoy recently with a carrier in the middle. It has 6 or 7 escorts, two lead, two beam and two rear, I think there was another according to sonar but did not spot it. The two rear were wide almost behind beam escorts. Strange thing is, I got the carrier and the escorts sailed on.

In the Pacific ocean in sh3 I doubt it?

He probably was playing Pacifc Aces.

astroenceladus 05-02-08 07:45 PM

Japanese Convoy details
 
Can anyone tell me where I can get a copy of S. Komamiya's Wartime Transportation Convoys History. I am trying to find details of a convoy that left Taiwan in late August, 1943 bound for Osaka, arriving September 1, 1943.

tater 05-02-08 07:54 PM

Yeah, I have that as well. I can zip it up and post a link.

Ducimus, open up RSRD and just look, it's in an easy to understand format in there :)


All times are GMT -5. The time now is 04:40 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright © 1995- 2025 Subsim®
"Subsim" is a registered trademark, all rights reserved.