New Torpedoes

[andycaccia]

Hi mates!
This is my first topic. I'd like to make new torpedoes for the upcoming cold war mod, and since we have a pair of working submarines I thought it was the right time for creating new kinds of torpedoes. My first experiment would be in modifying an existing torpedo i.e a Mk18 and make it a passive homing one using the guidance system of the Mk27 Cutie.

Is it possible??

[M. Sarsfield]

I would assume that it's an easy change/addition to a config file. If we can add new ship models, you shoudl be able to crate a new torpedo model.

I found this site talking about homing torpedo development from 1940-1946:
http://www.geocities.com/Pentagon/1592/ustorp4.htm

... and post-war "heavy weight" torpedoes:
http://www.geocities.com/Pentagon/1592/ustorp5.htm


It looks like you are after the Mk. 31, which is a Mk.18 equipped with passive homing.

[keltos01]

you can change easily the type, warhead and speed/range as idid to model the ijn type 93 and 92 (e) but i don't know about homing, will look into it

[M. Sarsfield]

Here's an interesting tidbit that I found:

Prior to the mid-1960s Soviet submarines had diving depths of 650 to 1000 ft and submerged speeds under 30 knots.

This should help with some of the torpedo parameters. Also, early acoustic torpedoes had safety features that prevented them from doing a 360 on the launching boat and a minimum operating depth so that they would not attack nearby ASW/friendly surface ships or even the launching sub at persicope depth.

[andycaccia]

Thank you M. Sarsfield, you've brought precios infos!
I'm currently at work with s3d to understand how a torpedo works (in game) and how to make a new homing torpedo...I think the best results would be achieved by "adding" new torpedoes instead of transofrming existing ones.

I'll keep you informed!

If anyone has some clues or ideas....be my guest.

[keltos01]

transforming existing ones reduces dramatically the amount of work necessary, as you have to edit quite a few files referring to the torpedoes you're using including the sub's. I plan to do that to go along with the human drivable japanese sub we're currently working on : a junsen B type. Have you asked the russian team ? I got their november design for a sub, which in turn should help me with the Junsen B.

[andycaccia]

This is the first time I ask for help with torpedoes, and I haven't asked the russians yet. I know that if I re-work existing torpedoes I will avoid a lot of extra work, but the fact is that I doubt I will be albe of creating a new homing torpdo using the mk 18 or the mk16 as basis. I modded the mk27 to a mk16 type of torpedo, but the result was a failure. The model used by the game was the short mk27 one, and even the proprieties of the torpedo (explosive power, speed, propulsion etc) remained the mk27 ones.

Basically I need to start with a G7e T-V like homing torpedo.
Is it possible o change the torpedo model of the mk 27??

[M. Sarsfield]

More than likely the Mk 27 has sensor nodes on it, like the ASW ships and aircraft. The Mk. 18 probably lacks nodes, since it's a straight shooter (after turning to the proper course set by the TDC). If you sped up the Mk. 27 and improved it's listening range (out to 1,000 yards), it could mimic a Mk. 31 or other early post-war acoustic torpedo.

For a late Cold War acoustic torpedo, modify a Mk. 14, since they eventually returned to combustion engines for torpedo motors - albeit much quieter and faster. Also, the Mk. 14 should have at least one node on it, since it uses magnetic detonation and it has to sense the the target to detonate. Just change the node to passive/active homing.

Post-war torpedoes had other features, too, like noise filters and delayed receivers (for active homing), so that they would ignore false echoes from cavitation, the sea floor, etc. when sending out a ping. They also designed in more sophisticated search patterns where the torpedo would circle and/or fish-tail as it listend for and closed in on a target. The Mk. 27 is pretty unbiased as to what it locks on to and in addition to slow velocity, it has a slow turning speed.

WWII also saw the beginning development of wire-guided torpedoes, but they weren't refined until the 50's and 60's.

Ironically, Mk. 14's stayed in service until something like 1981. Probably for training purposes.

If you read through the two links that I sent you, you'll get all sorts of cool ideas for Cold War fish.

[andycaccia]

Thank you M. Sarsfield, your help is precious and really appreciated.
But the problem is that I do not know how to add passive homing guidance on a torpedo that does'n have it.

I'd like to show you how (but you'll probably already know this) things appear in S3d when I open the torpedoes_us.sim but I can't insert the screenshot, che you tell me how to do that? It seems that i can only insert web url, what if i have a saved image?

[M. Sarsfield]

You'll need to post it to a server and then insert the url in your post. I have a private server that I usually post pictures to, but the other guys in here can provide some suggestions for public posting.

[andycaccia]

Yes, I feared this...oh well, it wasn't essential anyway.
I have to reinstall sh4, and then I will do some testing wit torpedoes.

[CinC Battleforce]

The USN developed the Mk 18 into an acustic homing torpedo. The Mk 28 was actually aboard subs that were working around Japan in 1945. I am so new to this game, so I don't know how to mod a torpedo, but Like the USS Batfish on her 7th War Patrol around Kyushu Island in 1945, I would love to have the Mk 28 torpedo.

The USN Mk 28 Torpedo had the following stats

Range: 4,000 yards (3,650 meters)
Speed: 19.6 knots
Warhead: 585 lbs of Torpex
Diameter 21 inches (53.3 cm)
Length: 20 ft 6 in (6.248 m)
Weight: 2,800 lbs
Poer: Electric Battery
(like the Mk 27, the 28 used acustic sounds from the enemy's ship to home in on)

The MK 18 had the following

Range: 4,000 yards (3,650 meters)
Speed: 29 knots
Warhead: 575 lbs of Torpex
Diameter 21 inches (53.3 cm)
Length: 20 ft 6 in (6.248 m)
Weight: 3,154 lbs
Power: Electric Battery

My question is can one of our talented modders make a torpedo we can add to the game using the Mk 18 as the base and giving it the homing ability of the Mk 27

[M. Sarsfield]

Got this from one of the website posted above...

The Mk.28 was a 21" x 246", 20 knot, submarine launched anti-surface vessel torpedo with a 585 lb warhead. It was equipped with passive homing and gyroscopic control which competed for rudder control. About 1750 of these torpedoes were produced by Westinghouse and Western Electric. Only fourteen were fired with four hits during WW II, but the torpedo remained in service until 1960.

I'm guessing that the devs felt it was under-utilized and didn't make any real difference in the war. Probably same thinking that caused them to leave out the Tench boats from the game.

[CinC Battleforce]

Bad thinking on their part. Both the Tench class boats and the Mk 28 torpedo were the state fo the art in 1945. And well they should have included both the boat and torpedo in the game just for the sake of being acurate.

[andycaccia]

Yes indeed it was a non accurate approach of the developers while making the game, as well as the same 450ft depth gauge on all boats when later gatos and all balaos had a 600ft one (fortunatly we have a mod to restore this). However a tench-class mod with start campaign in 1945 has been made. It uses the same balao model but tweaked a little in strength and with 2 torpedoes more in the forward reserve compartment.

It would be a nice adtition the mk 28 as you say, but i fear that adding new torpedoes is far more difficult than adding a new submarine.
I'm still working on this...

[rebel5555]

I know that modern torpedoes are wire guided. On an unrelated note can one edit the torpedo skins to add writing on them such as "To Tojo, From USS Drum"

[AlmightyTallest]

Man it would be great to get Mk 28 homing torpedoes to go with the Tench Class Ducimus made.

It seems like all of the ingredients are already there, wakeless electric Mk 18's and the the homing abilities of the Mk 27 combined into a neat torpedo option for late-war ships.

For fun, found this photo of the Mk-27 Cutie at the USS Pampanito site here: http://www.maritime.org/wish-mk27.htm I'm guessing that's the real paint scheme for the Mk-27?

Also, for those interested here's a link about the development of U.S. acoustic homing torpedoes from 1945 to 1950, it's very interesting reading. :) http://www.personal.psu.edu/pq9/post.html

And finally, a report from the USS Torsk (Tench Class) https://www.usna.com/NetCommunity/SSLPage.aspx?pid=636&srcid=502


"Early that day a merchant ship escorted by a single frigate was sighted. The captain decided to sink the frigate first with a new type of torpedo which homed in on a target’s screw noises. Torsk was one of the first submarines to get this new, secret Mk. 28 torpedo. The captain fired one torpedo which we saw hit the target’s stern and lift it up 45 degrees. A number of lifeboats were seen picking up the survivors and luckily for them they were only a few miles from shore."

"
The merchant ship headed toward a nearby port at full speed. Before we could get in a good position to fire torpedoes, it entered port. Our captain said maybe we should surface and fire at it with our 5 inch gun, but fortunately decided against it when a Japanese warplane appeared headed to our area. Soon more ship sounds were heard and we saw another frigate bearing down on us. The aircraft apparently saw Torsk and called in the frigate. The frigate apparently saw the periscope because he was heading directly toward it.
Another acoustic torpedo was fired at the frigate even though the acoustic torpedoes were designed to be fired from aft a target’s beam and the present target was heading directly toward us. The torpedo was fired when the target was about 2000 yards away and Torsk went deep to evade and hoped the torpedo hit. After what seemed to be an eternity, a loud explosion occurred very close to us, accompanied by breaking up noises. If that torpedo had not hit, there would have been a bad depth charging. They sent another frigate out to try to locate Torsk, but it was quite easily evaded after it had dropped a few depth charges - fortunately not close."

[M. Sarsfield]

I'm guessing that's the real paint scheme for the Mk-27?


I've seen the brown and hunter green colors on the Mk. 27. Batfish is getting one from a Navy museum in WA state, soon. I'll post a picture when we get it.

[AlmightyTallest]

Sounds great M. Sarsfield, I'd like to see the photos when you can post them.

[AlmightyTallest]

Just an update for those interested, below is a link to side view drawings and details on what must be every U.S. topedo made to 1962.

http://www.google.com/imgres?imgurl=http://hnsa.org/doc/jolie/img/pg94.jpg&imgrefurl=http://hnsa.org/doc/jolie/part2.htm&h=37&w=134&sz=27&tbnid=vm8Fg5MW3k8J:&tbnh=37&tbnw=134&prev=/images%3Fq%3DMk-28%2Btorpedo%2Bphoto&sa=X&oi=image_result&resnum=1&ct=image&cd=3

Just thought someone might use the data to create a skin and/or use the specifications to help create the new torpedoes for this sim.

[M. Sarsfield]

Great website, AT. Much more useful for SHIV purposes than the long-winded websites that I had found.

[AlmightyTallest]

Thanks Sarsfield, just trying to help out others here with far more talent than I when it comes to modding.

It's interesting for me because these Mk 28's were actually produced less than 30 miles from home in Sharon PA. Woohooo!! :D

[AlmightyTallest]

On the subject of Homing torpedoes in WW2 and the Mk28 in particular I found this gentleman's diary posted online from the USS Sennet on it's war Patrols in 1945.

http://www.sennet.org/diary_all.html

Here's some interesting info:

"The SENNET carried some MK 28 "stubby" torpedos which the crew called "Doodle Bugs." Two MK 28 "stubbys" could stowed on a rack that normally held one standard MK 14 torpedo. The MK 28 had to be fired at depths below 200' to keep it from picking up on SENNET's own propeller noises. "

The Sennet had to make a few dives to 580 feet to avoid some of the escorts according to the diary.

[andycaccia]

A mk 28 torpedo would be a good addition in the game, but I was wondering what was the max depth at which a torpedo could be launched.

[AlmightyTallest]

Well, I guess it would depend on the torpedo model being launched. Here's a site I found on firing Mk 14 and Mk 18 among other torpedoes.

http://www.maritime.org/fleetsub/tubes/chap11.htm

I don't quite understand what's being stated at that site, I'm guessing the maximum depth at which to fire a torpedo is 200 feet given the parameters at the site above? Seems to relate to the previous log I posted on the submarine firing the Mk28 while submerged at 200 feet.

Also, after looking at SH4 v1.5, I'm wondering if we could use some of the homing Electric powered German torpedoes and change their range and speed and reskin them to look like the Mk28 for the Pacific.

With SH4 v1.5 there's some neat upgrades to the U-boats with early anechoic coatings and such, would it be possible to give upgrades to the Fleet boats in the form of upgraded torpedo warheads? From this link:

http://www.geocities.com/Pentagon/1592/ustorp3.htm

The process of converting to Torpex torpedo warheads (and depth charge loadings) began with an order for 20 million pounds in early 1942. The first Torpex loaded warheadsfollowed late the same year. The 640 pounds of Torpex in a Mk.14 warhead was at least the equivalent of 960 pounds of TNT almost twice the destructive power of the original Mk.14

Torpex and TNT warheads were interchangeable. If there was a substantial change in weight, some adjustment to the depth gear was required

Comparisons with Japanese torpedoes often neglect the difference in high explosives. Japanese torpedoes used Type 97 high explosive, which is not significantly more powerful as an underwater explosive than TNT.



The reaction of the submariners to Torpex is apparent from an entry for 19 March 1943 in the fourth war patrol report of USS Wahoo: "0515H; Fired one torpex torpedo at medium sized freighter identified as KANKA MARU, 4,065 tons, range 750 yards, 120 port track, speed 9 knots. Hit. After part of ship disintegrated and the forward part sank in two minutes, and 26 seconds. These Torpex heads carry a [sic] awful wallop." This very substantial improvement in warheads is often overlooked in part because the torpedo identification does not automatically identify the warhead and even the warhead Mark doesn't unequivocally identify the high explosive. Some Mk.14-3A torpedoes were fitted with TNT warheads, most commonly Mk.15, and others with Torpex warheads, most commonly Mk.16. Furthermore torpedo warheads could be easily changed by a tender or depot. The standard ComSubPac format for war patrol reports did not require listing torpedo or warhead Marks and Mods. until after April 1943.

[CinC Battleforce]

I agree with the quotes about Torpex. Considering it had the explosive power of 1.5\1 ratio to TNT. Meaning a warhead say 1,500 pounds of Torpex would have an explosive power of a warhead armed with 2,250 pounds of TNT. I guess you can call that wallop.

[keltos01]

http://hosted.filefront.com/keltos01/ (http://hosted.filefront.com/keltos01/)

made a small mod changing the mk27 into a mk28, not a new torp yet but if you want to try it out. don't know if it displays mk27 or mk28, but specs are mk28

[AlmightyTallest]

Hey Keltos, thanks for that file!! It's a big step toward getting the new torpedo. Will try it out and report back.

[AlmightyTallest]

Well, I installed the mod with jsgme and tried some single player missions. I found that the US ships were now carrying variations of the Japanese torpedoes. Not a problem, since we're just experimenting with new torpedoes anyways. :)

I started a career in 1944 so that I could load up on the mk 28 to try them out and it crashes to the desktop everytime when I click on my submarine in the office. Once I unloaded the mod with jsgme, my campaign would start up fine.

I was using just Stock SH4 patched to v1.5 with no other mods installed.

[keltos01]

will look into it tonight, I'm home now !

[keltos01]

does appear in career mode in 1944, not before. description still that of mk 27, specs of mk28 speed 19.6 range 4000m. enjoy !
where is the description of the different torpedoes? it inst in localization like the german part..

mk28 made by and tested by keltos

http://hosted.filefront.com/keltos01/

http://aycu12.webshots.com/image/49771/2004157430512805267_rs.jpg (http://allyoucanupload.webshots.com/v/2004157430512805267)
http://aycu27.webshots.com/image/49106/2004163380500399271_rs.jpg (http://allyoucanupload.webshots.com/v/2004163380500399271)

[M. Sarsfield]

Thanks for the mod! Will download tonight. Can this be installed while on patrol?

[keltos01]

I guess so, actually everytime I try out a mod it's on a saved game, but for the american campaign that is :cry: I'm currently playing as a Jyunsen B with my Jap torp mod, gosh do I love those looong shots !

[AlmightyTallest]

Hey Sarsfield, lemme know how the Mk 28 work for you, I'm not going to get a chance to try them out until Saturday. Gonna be a loong week at work this week. :down:

Thanks again keltos, you should make a separate post that this torpedo is available for the fleet boats. :D

[keltos01]

ok doing it now
:D

[andycaccia]

I have been able to max out the performance of the Mk27, but I can not change the model, If it is impossible, then we will have a "small" mk 28...:shifty:

[AlmightyTallest]

Is it possible to create a new torpedo entry and create your own skin for it? Or could you just use the Mk 18 skins and size and use them for the Mk 28? Only other option I can think of is using one of the German electric guided torpedoes in 1.5 and converting it into a Mk 28 and putting it on the fleet boats.

[andycaccia]

Is it possible to create a new torpedo entry and create your own skin for it? Or could you just use the Mk 18 skins and size and use them for the Mk 28? Only other option I can think of is using one of the German electric guided torpedoes in 1.5 and converting it into a Mk 28 and putting it on the fleet boats.

This was also my attempt, but I failed. It sems that the only Homing torpedo is the mk27 one and i do not know how to create a new Homing torpedo with a 3d model which is not the small mk27 one.

[keltos01]

if we could only import 3d models using s3d..... btw anyone found where the description of the us torpedo types is in ver 1.5 ??

[elanaiba]

\data\UPCData\UPCLocalization\UPCLocalization.tsr

Look for lines such as (do not modify the left part, the ID, unless you know what you're doing. Edit the part on the righ):

Mark 18 Torpedo= the name of the torpedo, if
Mk18TorpInfo= Left side of the table, we put technical data there
Mk18TorpNotes= right side of the table, we put descriptions there (Notes for US Torpedoes are empty)

To create new accoustic torpedoes, its best you clone existing torps.

There are no sensors involved, but there's a special controller - amun_AcousticTorpedo, which needs to be placed on the torpedo instead of the normal amun_Torpedo.

The problem is deeper than this though, since every torpedo needs to have a special unique ID from a hardcoded list. So unless you actually replace one of the existing torpedoes (german or american) in the list, you can't really do this.

[skwasjer]

if we could only import 3d models using s3d..... btw anyone found where the description of the us torpedo types is in ver 1.5 ??
You can always reuse one of the longer models, and optionally reskin it...

[M. Sarsfield]

Hey Sarsfield, lemme know how the Mk 28 work for you, I'm not going to get a chance to try them out until Saturday. Gonna be a loong week at work this week. :down:

I started a new U.S. career as an S-42 boat early in the war. Pretty fun little toy, despite it's limitations.

I will start a late-war career and load up the Mk. 28's to let you know how they work. Did you modify the speed and agility of the Mk. 28 or just the speed?

[AlmightyTallest]

I'm not sure what was changed, speed and range at least. I didn't make the mod, so I don't know about the warhead being changed from the standard Mk27 as well.

[keltos01]

there is a file named change.txt included iwth my mod :doh:
here's the contents :

- changed the spec of the mk27 in the sim file as to match the speed
and range (19.5 /4000m) of the mark 28, the mk 27 is already electric !
Speed 19.6 range 4000
straight run = 500

- torpedo_Us.zon :
min ef = 149
max ef = 241
ap = 114
minRadius = 2.8
maxradius = 3.5

- changed the ammunition.upc to get it to display MK 28 instead of MK27
[Ammunition 13]
ID=Mk27Torpedo
NameDisplayable= MK 28 accoustic torpedo
Type= AmmoTorpedo
Subtype=Mk27TorpUS

keltos01

[M. Sarsfield]

there is a file named change.txt included iwth my mod :doh:

Of course there is. We're just lazy. :)

Seriously, I am currently heading toward Okinawa in the USS Apro (I believe) in Oct. '44 with 4 Mk. 28's forward and 4 aft - 2 loaded and 2 in reserve in each location. I'm on picket duty to support the Philippines invasion. I'll let you know what happens when I make an attack run tonight. The Mk. 28's are loaded into tubes 1 and 2 and I plan to launch them at the first thing that I see. Preferably a high speed target to see what they can really do.

What are all of the settings for under "torpedo_Us.zon"?

[keltos01]

min ef = 149
minimum efficiency or dammage

max ef = 241
maximum dammage

ap = 114
armor piercing (mm ?)

minRadius = 2.8
dammage if no direct hit (magnetic) minimum radius

maxradius = 3.5
dammage if no direct hit (magnetic) maximum radius

I adapt them using the original ratio of the mk14 as and the ammount of explosive carried by different types of torp :
130,210,100,2 and 2,5 would be the stock values of the mk14
k

[AlmightyTallest]

I read the change.txt file keltos, but it didn't say anything about the warhead size or damage being changed for your torpedoes. The Mk 27 has a relatively small warhead when compared to the Mk 28.

[M. Sarsfield]

AT, you two must have posted within a few seconds of each other. Keltos's last post explains it all.

[AlmightyTallest]

lol, your right, we were one minute apart on the posts. Thanks for the clarification Keltos. :)

[M. Sarsfield]

I still haven't had a chance to fire off a Mk. 28, yet. I'm trying to get to the bottom of why PE2 is such a huge impact to my system.

[AlmightyTallest]

It's no problem Sarsfield, I noticed you were having some problems with PE2, sorry to see it's continuing. I tried PE2 and didn't have many problems, but I decided to just wait for RFB 1.5 to put with PE2 so I don't have all my mods installed yet to try it out.