It's a dud - again!

[bcarter3]

So I upped my difficulty a little from easy so that I now get dud torpedos, and boy did I get some duds. I fired off 10 torpedos, all ten hit the mark, 7/10 were duds! Is this normal? How many duds should I expect to get? This seemed a little high to me. Heck, if 7/10 are going to be duds every time I might as well surface the dang boat and pop off deck gun shots, I might even hit something then!

[nfitzsimmons]

On my current patrol (late 1942-early 1943) the first 7 torpedos I fired worked, the next 9 were duds. Waiting to find out how many of the rest are bad. Playing with normal difficulty and TM 1.7.6.

[seafarer]

Not out of line with real world experience either. Read some of the patrol reports that are available online, and you'll hear of skippers firing 4 or more duds in a row, at least in 1942. Especially frustrating when they either saw or heard the fish clearly strike the target, but fail to detonate (such shots were officially recorded as misses too, which must have just upped the frustration the captain's were feeling about the mark 14).

[Wilcke]

Perfect!

[Capn_Sinky]

I have basically found that in the default SH4 and playing on Normal skill level that I have a 50%-70% failure rate for the Mark 14s. In WWII from 41 early 43 it was about this high. Most commanders have more duds than think but dont realize it. The Navy Ordinance Dept in 1942 basically told the Sub Commanders that either they were dumb or didn't take care of their torps. In some cases sub commanders had their torp crews field strip each torp before firing so they could verify that the torps inner mechanics were functioning. Course when they reported this to the Ord Dept they basically said "well that eliminates the torp, so you must be an idiot." Navy Ord Dept officials were not the most liked individuals at parties. There were several recorded instances of Jap freighters making it to their destinations with unexploded torps sticking out of the hull. Nothing ticks a sub commander off more than to risk life and limb to sneak in undetected, fire a full spread of fish, escape back to port and be called an idiot by a know nothing desk jocky.

Basically there are 3 types of failure actually 4 if you count the dreaded circle back (aka Tang killer) The game actually only informs you of one type, the dud warhead. In this case the torp strikes the target and if you are watching and it is running shallow enough you can actully see a splash on the side of the target. To compensate for this make sure the torp is set to slow speed and that it strikes the target at an angle of 70 degrees or less. basically this failure was due to a bad exploder firing pin that was crushed or bent on impact. This was eventually corrected by late 42 early 43 interestingly enough by using stronger firing pins made from jap props from aircraft shot down at Pearl. Talk about the benefits of recycling. "Hey and its even a "Green Torpedo" take that that Tojo."

The most common failure that I have seen and the computer didn't tell me it was a dud was the mag exploder failure. Basically the earths magnetic field causes the mag exploder to detonate before the torpedo impacts the target. I have on several occasions had the fish explode less than 100 yrds from exiting the tube. I thought the escorts were shooting at my periscope, until I went to the tactical map and saw only two fish headed toward the target and I knew I had fired three fish. To combat this set the exploder to contact only. Yes its against the regs, but hey my hand slipped oh-kay.

The third failure was because of a last minute redesign to the Mark 14. This resulted in the fish running on avg 11 feet too deep. This also is not reported as a dud. You just think you missed, untill you flip over to the tactical map and see a spread of fish swim harmlessly under a Isa BS. This combined with the reg stating to set the exploder to mag and the run depth set to 5 feet below the keel of the target basically meant a zero chance for a kill. To combat this find the depth of keel in the manual, multiply by 3.25 (got to do the metric conversion thingy) then subtract 12 and set to contact only. You may still have a run under every now and then in rough seas, but combine this with an angle of impact of less than 70 degrees and speed set to slow and you will see some drastic changes in torp performance.

The last and rarest failure is the circular run torp. This one basically circles around and spanks you on your backside. OUCH! As Bart S. would say "While I thought that it was physically impossible, this both sucks and blows at the same time!" Have not had to opportunity to experience this wonder as of yet (knock on the XO's skull) my best guess would be "Ahead Flank! Crash Dive!" Followed quickly by a few propositions to a higher diety that one's choices regarding women and drink will change if the boat can pass through 100ft before the fish completes its turn.

The other thing to assist you in your mission prior to mid 42 is to swap out some Mark 14s for some older Mark 10s before you go on patrol. I make it a habit of replacing about half of my Mark 14s with Mark 10s before leaving port. I have yet to return from patrol empty handed. It takes a little cognative re-assessment when planning your attack, but it will be well worth the effort.

Good Luck and Good Hunting!

Capn_Sinky (aka Stinky)
O.I.C.I.C.
Officer In Charge of Ice Ceam

USS Drum

[bcarter3]

Awesome post Cpt. Sinky, thank you so much.

If the failure rate is so high on the Mk. 14's why would you even carry any? Why not swap out the full inventory for Mk. 10's instead. Yes I know they are steam, have a slightly shorter range and only one speed setting (as far as I can tell), but wouldnt you rather have reliability vs. range?

I know when I set up for an ambush I sit 1000-2000 yards away. It seems that the Mk 10's would still work in this scenario, or am I missing something obvious here?

[Capn_Sinky]

Thanks, Sorry about the length, Im a bit of a technical nerd.

Good question, why not all Mk10s. Well it seems that when I refit and select Mk10s that the next time I return to port there are not as many Mk10s left. So I am assuming (and we all know what that means) that the supply is limited. Dont want to use them all up at once. Plus you might tick off the pig boat capns, and remember they DON'T have ice cream makers so there always in a bad mood:D

True the Mk 10 is more reliable but it also has a smaller warhead (500lbs) the Mk 14s have, and my mind is failing me either 800 or 900lb warhead. So a Mk 10 is a little over half as powerfull.

Now here is where "Stinky Logic" comes in:

Gato sub can carry 24 fish. So if you carry only mk 14 you are carrying a little over 19,000 lbs of explosive. Now if you go with avg failure rate of 50% you are really only delivering about 9500 lbs of explosives to Mr. Tojo. Could be more or less depends on batch of fish. But 12 duds can really be a morale breaker, and a bad day at the office if it happens at the wrong time:dead: .

Now if you carry half and half, 12 mk 10s = 6000lbs of explosive force. 12 Mk 14s are about 9500 lbs, then avg out the 50% failure your delivering about 4800lbs. So now with a half and half load your only avering about 6 dud vs 12 duds and your delivering almost 11,000lbs of trouble for the imperial navy vs 9500lbs with the Mk 14.

Also Mk 14s can be handy little fish if you can see the bad guys in the harbor but can't get in close enough to use a Mk10. Set em to run slow and they will go all day. (actually 9000yrds which gives you almost 9 minutes to get somewere safe.) Wake Island is a good example, to use the Mk 10s you got to get right up under the bulldogs nose. But with the Mk14 you can stand back across the street and toss a few his way and be at a safe depth by the time he figures out what is going on.

Hope that helps.

Good Luck and Good Hunting!

Capn_Sinky (aka Stinky)
O.I.C.I.C.
Officer In Charge of Ice Cream

USS Drum

[Paajtor]

Good read here....thx guys:up:

[bcarter3]

....

Now here is where "Stinky Logic" comes in:

Gato sub can carry 24 fish. So if you carry only mk 14 you are carrying a little over 19,000 lbs of explosive. Now if you go with avg failure rate of 50% you are really only delivering about 9500 lbs of explosives to Mr. Tojo. Could be more or less depends on batch of fish. But 12 duds can really be a morale breaker, and a bad day at the office if it happens at the wrong time:dead: .

Now if you carry half and half, 12 mk 10s = 6000lbs of explosive force. 12 Mk 14s are about 9500 lbs, then avg out the 50% failure your delivering about 4800lbs. So now with a half and half load your only avering about 6 dud vs 12 duds and your delivering almost 11,000lbs of trouble for the imperial navy vs 9500lbs with the Mk 14.

Also Mk 14s can be handy little fish if you can see the bad guys in the harbor but can't get in close enough to use a Mk10. Set em to run slow and they will go all day. (actually 9000yrds which gives you almost 9 minutes to get somewere safe.) Wake Island is a good example, to use the Mk 10s you got to get right up under the bulldogs nose. But with the Mk14 you can stand back across the street and toss a few his way and be at a safe depth by the time he figures out what is going on.

Hope that helps.

Good Luck and Good Hunting!

Capn_Sinky (aka Stinky)
O.I.C.I.C.
Officer In Charge of Ice Cream

USS Drum

I like that logic and it makes a lot of sense. By jingo Cap'n you just converted me to half and half!! Again, awesome post thank you.

[bcarter3]

Been thinking about the half and half, and a question sprang to mind. If you use the Natural Sinking Mod (NSM) and you used a Mk. 10 in two separate compartments then surely the explosive power wouldn't matter. In which case the Mk 10's become superior in terms of sinking ships at sea because they make the most reliable "holes" in the hulls. Any thoughts?

[swdw]

Awesome post Cpt. Sinky, thank you so much.

If the failure rate is so high on the Mk. 14's why would you even carry any? Why not swap out the full inventory for Mk. 10's instead. Yes I know they are steam, have a slightly shorter range and only one speed setting (as far as I can tell), but wouldnt you rather have reliability vs. range?

I know when I set up for an ambush I sit 1000-2000 yards away. It seems that the Mk 10's would still work in this scenario, or am I missing something obvious here?
MK 10's have a smaller warhead and require more hits. In real life they could not be set by the TDC and I ran across a reference to the fact they had more problems with the azimuth gyro (stability) than the Mk14. So once the fish was in the tube you needed to keep a constant AOB, not close the range, and hope the target didn't change speed before firing. Azimuth gyro problems result in more frequent problems like circle runners. They also ran deeper than the depth setting used.

We're doing some digging, but some mods may not even have had a gyro angle setting, but not sure yet.

They sufferedd from duds too but not quite as high a number as the Mk14. This was because of the slower speed and less mass.

[SteamWake]

7 out of 10 is pretty hard luck...

But hey it happens.

[LukeFF]

For those that are curious, (and since swdw is here) here are the torpdeo parameters currently being used for RFB:

Mark 10:
Circle-runner chance: 1.5%
Gyro angle chance: 1.5%, max angle of 50 degrees
Premature explosions: none
Depth-keeping error: 4 feet, 100% chance
Dud chance: 0-70 degrees: 2.5%. 70-90 degrees: 5%.Mark 14/23:
Circle runner chance: 1% (to 7-31-1942); 0.5% (after 7-31-1942)
Gyro angle error: 1% percent chance, max angle of 50 degrees (same dates as circle runners), 0.5% chance after 7-31-1942.
Depth-keeping error: 8-15 feet, 100% chance (up to 7-31-1942)
Premature explosions: rough seas: 75%; moderate seas: 60%; light seas: 10% (up to the end of September 1943)
Duds: chance reduced by 50% when using low speed setting. Impact angle 0-35 degrees: 5% chance; 35-70 degrees: 35% chance; 70-90 degrees: 70% chance (up do 9-29-1943). These chances, after this date, will be scaled down in a future release (currently it's not possible).
Magnetic detonation range: 5 feet. This, combined with the depth keeping errors, makes a successful magnetic hit very difficult, especially when targeting shallow-draft ships. Magnetic detonator is disabled at the end of September 1943.

[Capn_Sinky]

Haven't seen the data on the MK 10 failures. Interesting. In stock SH4 on normal and hard they peform much more reliable than the MK14s. Not as powerful as the MK 14 but good enough. Give me reliability over power anyday. Meanwhile a dud is a dud is a dud.

Check this out:smug:
http://usswashington.com/worldwar2plus55/dl12au42.htm

[bookworm_020]

Basically this failure was due to a bad exploder firing pin that was crushed or bent on impact. This was eventually corrected by late 42 early 43 interestingly enough by using stronger firing pins made from jap props from aircraft shot down at Pearl.


The pin was also too heavy, so that it would also get jamed, causing a dud. A quck fix done was to put the pins in a lathe and turn them down, reducing their weight and increasing the success rate!:up:

If the failure rate is so high on the Mk. 14's why would you even carry any? Why not swap out the full inventory for Mk. 10's instead. Yes I know they are steam, have a slightly shorter range and only one speed setting (as far as I can tell), but wouldnt you rather have reliability vs. range?

The mark 10 torps had there own problems. Skippers running out of Brisbane reported that the mark 10's were slow to imput data (tought when you need to do a snap shot of a BB!:-?), had major reliablity issues due to parts that were worn out due to excessive use. The torps had been used pre-war, but to save money they were programed to float at the end of the run, so that they could be reused over and over again. They were also slower than more modern fish, giving the taget a better chance of spoting them (they were steam powered, so they left a trail) and getting out of the way.

[CCIP]

I remember designing the mod for the Mk.14 failure rates, and indeed that's close to where I was aiming for! From what I could gather, the failure rate in early war was around 60-70% due to various reasons (which includes not just duds per se but also depth problems, gyro problems and premature detonations). So what you're getting is pretty much what you should expect!

[Sailor Steve]

If the failure rate is so high on the Mk. 14's why would you even carry any? Why not swap out the full inventory for Mk. 10's instead. Yes I know they are steam, have a slightly shorter range and only one speed setting (as far as I can tell), but wouldnt you rather have reliability vs. range?

I know when I set up for an ambush I sit 1000-2000 yards away. It seems that the Mk 10's would still work in this scenario, or am I missing something obvious here?
The main reason I can see for not carrying all Mk 10s is hindsight. They didn't have that option, primarily because they didn't know what the problem was. I play to replicate the same experience they had, so I keep the loadouts they had historically.

But that's just me.

[Galanti]

The key is to set your Mk.14's to run slow = huuuge reduction in duds. It always burns my arse to do this, though, because IRL the skippers didn't have the benefit of hindsight like we do now. Plus, a 45-knot run to a 1200 yard track doesn't give 'em much time to react!

Sometimes I almost wish I had starting playing this game with a complete ignorance of the RL torpedo problems. Then again, if we didn't know about the problems they had back then, we wouldn't have had cause to bitch when they weren't included in the stock game!

[Capn_Sinky]

Was in the South China Sea was smack in the middle of a huge convoy of merchants and a very large passenger liner had three mark 14s left two in the bow and one in the stern. The escorst were on to me, had made several passes already. The slop buckets at the stations were about to spill over from all the diving up and down. Finally caught a break fired two shots less than 600 yrds, dead on the liner perfect shot. Both struck portside the right under the stack. And whouldnt you know it both were duds:huh:

Escorts coming at me from all directions dived under the liner came out the other side and ran like a scalded dog. about 2500 yards away with the liner at a bearing of about 210 I fired my last fish and hit him right on the stern. Sat there and watched him grind to a stop. Must have got his running gear. Anyway nothing I could do. Three escorts circling. Had to bug out batts were down to about 15% and CO2 was rising. Had to leave 18,000 tons siting there. Once I got far enough away I radioed in. Sooooo sad.:cry:

[SuperCavitation]

The third failure was because of a last minute redesign to the Mark 14. This resulted in the fish running on avg 11 feet too deep. This also is not reported as a dud. You just think you missed, untill you flip over to the tactical map and see a spread of fish swim harmlessly under a Isa BS. This combined with the reg stating to set the exploder to mag and the run depth set to 5 feet below the keel of the target basically meant a zero chance for a kill. To combat this find the depth of keel in the manual, multiply by 3.25 (got to do the metric conversion thingy) then subtract 12 and set to contact only.

Sinky,

Are you saying the torp depth gauge in the US subs is metric?

http://www.jediforest.com/images/torpgauge.JPG

This gauge? Even though I'm set to use "Imperial" in my game settings?

[FIREWALL]

I never tic dud anymore. I miss enough as it is with manual targeting. :rotfl:

[skwasjer]

I usually have quite a few duds when I set the torps to deep with impact pistols, even at 90 degrees, as they just bounce of the bottom of the hull. I prefer to run torps at low speed, reducing the chance of faulty pistols or prematures. Either I use magnetic (but they often run to deep) or with impact pistols set them relatively shallow (at no more than 1/2 the draft, less with warships). Duds are so annoying, especially when you see a big BB sail by. *** klunk *** Torpedo is a dud, sir! arrrghhh...

[AkbarGulag]

Duds are so annoying, especially when you see a big BB sail by. *** klunk *** Torpedo is a dud, sir! arrrghhh...

The scary part is Squash, you know the BB heard it!

[SuperCavitation]

The third failure was because of a last minute redesign to the Mark 14. This resulted in the fish running on avg 11 feet too deep. This also is not reported as a dud. You just think you missed, untill you flip over to the tactical map and see a spread of fish swim harmlessly under a Isa BS. This combined with the reg stating to set the exploder to mag and the run depth set to 5 feet below the keel of the target basically meant a zero chance for a kill. To combat this find the depth of keel in the manual, multiply by 3.25 (got to do the metric conversion thingy) then subtract 12 and set to contact only.

Sinky,

Are you saying the torp depth gauge in the US subs is metric?

http://www.jediforest.com/images/torpgauge.JPG

This gauge? Even though I'm set to use "Imperial" in my game settings?

I swear I'm not as dumb as (I hope) I appear.... but my torps are still running deep.

I just completed an encounter with a Kongo, 27.9 draft. Multiplied, that's 90.6.. Minus 11 = 79.6..... :o

Soooo... I set the torp depth at 15 per the US gauge illustrated above. That's a give of, what? 13? And three of them just flew right under her.

Then, I decided to divide.... 27.9/3.25=8.6 rough. Cant take 11 away from that unless you consider the deck gun. :p

*Lost on patrol with torps that he can't program* MAN TEH DECK GUN!!1:arrgh!:

[Major Johnson]

Let's get this straight, the gauge is supposed to be read in feet not meters/yds, correct?? Meaning that the Kongo draft as stated above is actually 27.9 ft. It appears that SuperCavitation is multiplying that by 3. That can't be right, can it??

[Wilcke]

Imperial; those are feet, go to the torp training mission, set them for 3 feet and shoot a bunch and follow them with the cam. Then shoot some at 50, easy to verify.

I about had a heart attack here:nope: , its early in the moring and the caffeine still has not kicked in....slow deep breaths....easy there Mr. Heart

[Capn_Sinky]

Sorry about the confusion. The torpedo depth gauge in game is imperial measurements. The paper manual however is in metrics. For example the Yamato (in the manual) shows a depth of 10.9 meters. To convert that depth to feet you multiply 10.9 x 3.25 which gives you a depth to keel of roughly 35.5 feet. You would then sub tract 12 feet from that (to count for the running too deep error) and you get 23 feet.(Yeah yeah yeah, I know its 3.28 blah blah blah feet per meter but were not putting men on the moon, were just trying to compensate for a freaking crapy torpedo, sorry about that, just know there are rivit counters in the crowd :know: ) All things considered then you should hit between 23 and 35 feet below waterline. You want to hit as close to the keel as possible, but not undershoot completely. Also make sure you get a spread. 20 holes in the same compartment does not make a boat sink any faster. Course i do wonder if you kept the same aiming point yet vary the depth vertically, could you saw him in half?:hmm:

Sorry about the confusion. Oh the horror, there is probably a Blue Whale somewhere in the pacific wanting to know who's got it out for him, and its all my fault :oops:

[Major Johnson]

I about had a heart attack here:nope: , its early in the moring and the caffeine still has not kicked in....slow deep breaths....easy there Mr. Heart

:rotfl:

I know I'm as much at fault as anyone for sometimes asking obvious questions. But I'm determined to get the basics of this game yet. I waited almost 10 freakin years for the franchise to get back to the pacific, and dammit, I'm not gonna be cheated!!!

[SuperCavitation]

I just completed an encounter with a Kongo, 27.9 draft....

Soooo... I set the torp depth at 15 per the US gauge illustrated above. That's a give of, what? 13? And three of them just flew right under her.

Right so, I tried in feet and three still went under her. The way I sunk her was to leave the daggum gauge at 6' and unload the tubes. I probably should have spread them but I was so aggrevated at that point I just wanted to sink her and move on. Lord, the DD were ticked, too.

I'm going to start setting my torps with a 15' give where possible (assuming the wife lets me play this weekend) and see what that does.

EDIT: LOL! Sorry, Wilcke. =-P

[Capn_Sinky]

Super C what was your range when the three went under? Just curious.

I feel your pain though man. What I hate is when you fire off six good ones and some kamakazi DD jumps between you and your target and takes em. Nothing worse than watching 6 torps hit a destroyer that was dead after the first two. As it's going down four more... whoom! whoom! whoom! whoom!:damn:

[SuperCavitation]

I was between 1200 and 1500 yards away, using the compass to draw a 1200 circle. I normally attack at 1000. But I knew these guys could see me a bit easier, so I drew a 1200 and still didn't get to the edge of it. I was too scared, lol. :p

[dean_acheson]

So I upped my difficulty a little from easy so that I now get dud torpedos, and boy did I get some duds. I fired off 10 torpedos, all ten hit the mark, 7/10 were duds! Is this normal? How many duds should I expect to get? This seemed a little high to me. Heck, if 7/10 are going to be duds every time I might as well surface the dang boat and pop off deck gun shots, I might even hit something then!

Welcome to realism, in the real show, I find it amazing that a bunch of skippers didn't take their sidearms to the torpedo folks at the BuOrd.

Simply amazing...

[dean_acheson]

That was a great post Capn Sinky.....

I seem to remember somewhere that the depth problem was caused by the BuOrd testing the depths somewhere, Panama? New England? and the conditions in the Pacific being different, causing the torps to run deep.

Atmospherics or something like that....wish I could remember where I read that.

I have basically found that in the default SH4 and playing on Normal skill level that I have a 50%-70% failure rate for the Mark 14s. In WWII from 41 early 43 it was about this high. Most commanders have more duds than think but dont realize it. The Navy Ordinance Dept in 1942 basically told the Sub Commanders that either they were dumb or didn't take care of their torps. In some cases sub commanders had their torp crews field strip each torp before firing so they could verify that the torps inner mechanics were functioning. Course when they reported this to the Ord Dept they basically said "well that eliminates the torp, so you must be an idiot." Navy Ord Dept officials were not the most liked individuals at parties. There were several recorded instances of Jap freighters making it to their destinations with unexploded torps sticking out of the hull. Nothing ticks a sub commander off more than to risk life and limb to sneak in undetected, fire a full spread of fish, escape back to port and be called an idiot by a know nothing desk jocky.

[dean_acheson]

Some of this is in TM, I think, you would want to talk to Duci about it, but I think he modeled in, or moded someone else's mod, that modeled in the torp problems to be more realistic.

I'm waiting for 1.5 to show up, and then running some with TMO and seeing. As for me, I was getting a bit tired of all my torps working, really ahistorical.

Sorry for the triple posts, but after being here for like seven years, I'm excited to make it to 1000 posts.:rock:

[Capn_Sinky]

They did most of their testing on the Mk 14 at Newport Torpedo Station. The depth issues had a little to do with the location (not as much as the mag exploder though) The biggest issue for the depth was with the placement of the depth sensor and the weight of the warhead they tested with was different then the actual warhead used in combat.

Great grazing for nerd herds here
http://www.geocities.com/Pentagon/1592/ustorp2.htm

[dean_acheson]

Looked up some of the reasons in Robert Gannon's "Hellions of the Deep: The Development of American Torpedoes in World War II"

He lists, on Pages 85-6 a few different reasons for the depth problem, including:

1. Problems with prewar testing diagonostics and methods.

2. The depth control system axis layout.

3. An uncompensated increase in the exposive size.

4. Depth sensors only tested in still water, not while the torp was moving.

5. Lack of compenstation for combat conditions.

6. various malfunctions of "mechanical gadgets"

7. crew mistakes.

I'm sure that I read something somewhere about the differences in sea pressure between Newport and the South Pacific. That might be crazy, I'm still pretty sure that I read it somewhere. :doh: