Technical fact stuf about WWII

Gary Grigsby's strategic level wargame covering the entire War in the Pacific from 1941 to 1945 or beyond.

Moderators: Joel Billings, wdolson, Don Bowen, mogami

Post Reply
User avatar
wild_Willie2
Posts: 2934
Joined: Fri Oct 08, 2004 10:33 am
Location: Arnhem (holland) yes a bridge to far...

Technical fact stuf about WWII

Post by wild_Willie2 »

Hi there, this is a VERY interesting link.

http://www.ww2pacific.com/notuntil.html

like this:

24July43. Submarine Tinosa (SS-283) torpedoes Japanese oiler No. 3 Tonan Maru. Tinosa fires 15 torpedoes; 13 hit but only two explode! The incident highlights torpedo exploder problems that have plagued the submarine force since the beginning of the war.

In vinum illic est sapientia , in matera illic est vires , in aqua illic es bacteria.

In wine there is wisdom, in beer there is strength, in water there are bacteria.
User avatar
castor troy
Posts: 14331
Joined: Mon Aug 23, 2004 10:17 am
Location: Austria

RE: Technical fact stuf about WWII

Post by castor troy »

ORIGINAL: wild_Willie2

Hi there, this is a VERY interesting link.

http://www.ww2pacific.com/notuntil.html

like this:

24July43. Submarine Tinosa (SS-283) torpedoes Japanese oiler No. 3 Tonan Maru. Tinosa fires 15 torpedoes; 13 hit but only two explode! The incident highlights torpedo exploder problems that have plagued the submarine force since the beginning of the war.



while you can have 11 out of 13 dud MK14s in WITP, you will never achieve such a hit rate of sub launched torps. It´s more like 10% of torps hit. 6 launched - 1 hit is usual, add to that the salvoes that missed and you have the 10% hit rate of WITP.
User avatar
DaveB
Posts: 151
Joined: Sun Aug 03, 2003 11:59 pm
Location: Forres Scotland
Contact:

RE: Technical fact stuf about WWII

Post by DaveB »

Actually -
how did Tinosa know 13 hit? It's not like they could hear a distant thump, or the Jap captain leaned over the side with a board reading '9 hit so far, all dud - good news yankee dog!'

The dud torp issue has been well covered, Clay Blair Jr's 'Silent Victory' contains as good an account as any. My favourite version, however, comes from Hollywood - I suspect it was the Clark Gable version of 'Run Silent, Run Deep' (well, James Garner's "Up Persicope" hardly compares, does it?) Seeing Sub officers standing nonchalantly around while stout hearted petty officer types dropped torps onto the pavement 5 feet alongside nose first to prove the impact fuse was duff.... that's the stuff!

Witp is another matter - I turn the auto sub doctrine stuff off, and as a result my subs kill too often. With it on my subs don't seem to attack...if I saw 'Sailfish fires 6 torps, 5 sink, one chases Sailfish' I wouldn't mind so much - I don't mind the torps not working, it's the apparent lack of attacks attempted I think is unreal.

By the way, v the AI at least, my favourite tactic for messing the Japanese up from the word go is to liberally sprinkle subs from Singapore to Batan Island, and have IL4c's flying anti ship at 2000 ft from S China. Those IL4c's are damn good at thwacking AKs. Add in all the Swordfish and Wildebeests at Singapore and it's sayonara for Japanese AK/AP skippers.

Oh, stick enough subs west and south of Borneo, Balikpapan etc and you can gently dissuade the KB and mini KB from touring the block too often...especially if you put the A24's on Menado.

AE is due out in approx 6 weeks by the way - this is MY release date, but I think Matrix ought to go for it.

Dave
User avatar
AW1Steve
Posts: 14531
Joined: Sat Mar 10, 2007 6:32 am
Location: Mordor aka Illlinois

RE: Technical fact stuf about WWII

Post by AW1Steve »

ORIGINAL: DaveB

Actually -
how did Tinosa know 13 hit? It's not like they could hear a distant thump, or the Jap captain leaned over the side with a board reading '9 hit so far, all dud - good news yankee dog!'

The dud torp issue has been well covered, Clay Blair Jr's 'Silent Victory' contains as good an account as any. My favourite version, however, comes from Hollywood - I suspect it was the Clark Gable version of 'Run Silent, Run Deep' (well, James Garner's "Up Persicope" hardly compares, does it?) Seeing Sub officers standing nonchalantly around while stout hearted petty officer types dropped torps onto the pavement 5 feet alongside nose first to prove the impact fuse was duff.... that's the stuff!

Witp is another matter - I turn the auto sub doctrine stuff off, and as a result my subs kill too often. With it on my subs don't seem to attack...if I saw 'Sailfish fires 6 torps, 5 sink, one chases Sailfish' I wouldn't mind so much - I don't mind the torps not working, it's the apparent lack of attacks attempted I think is unreal.

By the way, v the AI at least, my favourite tactic for messing the Japanese up from the word go is to liberally sprinkle subs from Singapore to Batan Island, and have IL4c's flying anti ship at 2000 ft from S China. Those IL4c's are damn good at thwacking AKs. Add in all the Swordfish and Wildebeests at Singapore and it's sayonara for Japanese AK/AP skippers.

Oh, stick enough subs west and south of Borneo, Balikpapan etc and you can gently dissuade the KB and mini KB from touring the block too often...especially if you put the A24's on Menado.

AE is due out in approx 6 weeks by the way - this is MY release date, but I think Matrix ought to go for it.

Dave

Actually Dave , I think the scene that you are desrcibing is in a John Wayne movie , Operation Pacific
User avatar
LargeSlowTarget
Posts: 5085
Joined: Sat Sep 23, 2000 8:00 am
Location: Hessen, Germany - now living in France

RE: Technical fact stuf about WWII

Post by LargeSlowTarget »

ORIGINAL: DaveB

Actually -
how did Tinosa know 13 hit? It's not like they could hear a distant thump, or the Jap captain leaned over the side with a board reading '9 hit so far, all dud - good news yankee dog!'

Actually yes - the commander of the Tinosa observed small splashes from torpedoes hitting the hull without exploding, even saw a torpedo jump out of the water upon impact, and the crew heard the metallic thud of torpedoes hitting the hull. First spread of four torpedoes from perpendicular firing position yielded two splashes. Next two torpedoes, fired from a bad angle since the target turned away from the sub, actually exploded and left the tanker dead in the water. Tinosa again took up textbook position perpendicular to the stationary target and fired nine more torpedoes one by one at point-blank range (checking each torp before firing), observing splashes etc. but no explosions. The commander saved the last torpedo for inspection back in port.
User avatar
DaveB
Posts: 151
Joined: Sun Aug 03, 2003 11:59 pm
Location: Forres Scotland
Contact:

RE: Technical fact stuf about WWII

Post by DaveB »

Oh billhooks!
John Wayne eh? Well, that's my theory sunk! I can't be held accountable, I watched a lot of John Wayne movies as a kid. (At least it wasn't James Garner). You'll be telling me next that General Custer didn't parachute into Burma.... (5 smartie points for the first poster to make the link).

I'd still be inclined to disagree - very politely - with your interpretation... p436 of Silent Victory carries an extract from the patrol report which says (first off) they fired 4 and believe 2 hit, seeing splashes forward. Following that there's a chronological report that says (typically) "1011 Fired eighth torpedo. Hit. No apparent effect."

Forgive me if my memory plays false here, but I seem to recall air flasks causing small 'explosions' which would occur short of the target, but appear, in the scope, to be small exlosions on the target. They were prematures. I'm not saying the torps didn't hit (although it would be remarkable if they did, as torpedo depth keeping was in fact a large part of the problem, and a good proportion of the 13 torps would have passed UNDER the keel if correctly set) just that the combination of problems: ie

1) Magnetic exploder didn't
2) The closer to a 90 degree hit you got, the more likely you were to damage the contact exploder
3) Premature magnetic detonations were interpreted - no doubt as they were on the line of sight to the target - as hits when the warhead was actually prematurely triggered
4) Torps didn't run at the preset depth, (11 feet deeper than  set is one quoted figure)...it's hard to hit something you are passing below.

I'm not, for a single moment, looking to downplay the achievements of the crews - it must have been heartbreaking to go where they did, only to find their weapons didn't work. I think it's unlikely, however, that all 13 actually hit for Tinosa - I am pretty sure that most of the 13 were properly aimed, set, and sent on their way - it's Bu Ord's fault they didn't sink the Tonan Maru. It must have been, for the most part, a bit like some sort of shotgun blast - aim a dozen torps along the same bearing and depth, and watch each and every one go its own way at a random depth.

Dave
User avatar
DuckofTindalos
Posts: 39781
Joined: Fri Apr 22, 2005 11:53 pm
Location: Denmark

RE: Technical fact stuf about WWII

Post by DuckofTindalos »

ORIGINAL: DaveB

Oh billhooks!
John Wayne eh? Well, that's my theory sunk! I can't be held accountable, I watched a lot of John Wayne movies as a kid. (At least it wasn't James Garner). You'll be telling me next that General Custer didn't parachute into Burma.... (5 smartie points for the first poster to make the link).

They Died with Their Boots On and Objective: Burma, both with Errol Flynn...
We are all dreams of the Giant Space Butterfly.
User avatar
rtrapasso
Posts: 22655
Joined: Tue Sep 03, 2002 4:31 am

RE: Technical fact stuf about WWII

Post by rtrapasso »

ORIGINAL: DaveB

Actually -
how did Tinosa know 13 hit? It's not like they could hear a distant thump, or the Jap captain leaned over the side with a board reading '9 hit so far, all dud - good news yankee dog!'

Actually, if i recall the story correctly, the first torps blew off the prop, and the ship was a sitting duck. They approached to point blank range and fired torp after torp - they could see and hear the torps hitting one after another.

The Japanese were frantic and were very busy shooting at the periscope. The ship (again, iirc) was a TK converted from a whale factory ship.

EDIT: Whoops - LST already had the same story.

BTW - this is what finally prompted Lockwood to conduct firing tests at Kahoolawe Is. (sp?) off Mauii.
User avatar
wdolson
Posts: 7690
Joined: Tue Jun 27, 2006 9:56 pm
Location: Near Portland, OR

RE: Technical fact stuf about WWII

Post by wdolson »

The torpedo they brought back was test fired into a cliff in Hawaii where it promptly exploded.  The brass finally believed the sub skippers though and an investigation revealed that the firing pin was too fragile.  In a glancing hit, the pin would work, but in a more textbook shot, the pin would shatter before setting off the charge.

In a bit of irony, they set about replacing the firing pins on all torpedoes at Pearl with new pins fashioned out of a Zero propeller left over from the Pearl Harbor raid.

If the brass had only listened sooner, the war may have been shortened by a few months.  In the first year and a half of the war, the US submarine fleet got a lot of lost opportunities because of dud torpedoes.

Bill
WIS Development Team
User avatar
Jorm
Posts: 547
Joined: Tue Jun 25, 2002 5:40 am
Location: Melbourne

RE: Technical fact stuf about WWII

Post by Jorm »

24 Jul, 1943
USS Tinosa (Lt.Cdr. L.R. Daspit) torpedoes and damages the Japanese oiler Tonan Maru No.3 (19210 GRT) west of Truk in position 06º56'N, 147º52'E.

Tinosa fired no fewer than 15 torpedos, of which 10 hit but only two exploded ! 8 were duds....the ship was heavily damaged but limped into Truk. It illustrated the unreliability of the American torpedoes, and efforts were redoubled to fix the faulty exploder mechanism after the Tinosa captain filed his report on the incident. He could see the Japanese crew running around the decks pointing at the torpeodes before they hit, but a loud thud was the only result time after time.

User avatar
DaveB
Posts: 151
Joined: Sun Aug 03, 2003 11:59 pm
Location: Forres Scotland
Contact:

RE: Technical fact stuf about WWII

Post by DaveB »

Terminus,
--------------------------------------------------------------
| (Smartie) (Smartie) (Smartie) (Smartie) (Smartie) |
-------------------------------------------------------------

Cut out the above ticket, glue into front of Witp manual <g>

Dave
(Edited to realign)
bradfordkay
Posts: 8686
Joined: Sun Mar 24, 2002 8:39 am
Location: Olympia, WA

RE: Technical fact stuf about WWII

Post by bradfordkay »

Dave, I tried that, but for some reason my computer keeps messing it up. Whenever the name "Terminus" is used in proximity to the word "smartie" it changes the latter to something that starts out the same but drops the last two letters and adds three others...[;)]
fair winds,
Brad
User avatar
DuckofTindalos
Posts: 39781
Joined: Fri Apr 22, 2005 11:53 pm
Location: Denmark

RE: Technical fact stuf about WWII

Post by DuckofTindalos »

[:'(]
We are all dreams of the Giant Space Butterfly.
John Lansford
Posts: 2664
Joined: Mon Apr 29, 2002 12:40 am

RE: Technical fact stuf about WWII

Post by John Lansford »

The weak exploder pins was the last of numerous problems US torpedoes had; everyone thought they were reliable after correcting the depth problem and turning off the magnetic detonator, but the exploder pins were so weak they'd actually deform on a 90 degree hit instead of setting off the explosive.&nbsp; Until the contact pins were strengthened, sub commanders were told to aim for angled impacts, as tests showed the weak pins would work better (but still not all that reliably) if the torpedo hit at an acute angle.

Clay Blair's Silent Service goes into a lot of depth on the torpedo problems.
Post Reply

Return to “War In The Pacific - Struggle Against Japan 1941 - 1945”