Quick question about spreads

[ddiplock]

Is the offset angle dial in the US TDC the best way of setting a torpedo spread?

So, you'd set an offset angle of say 4 or 5 degrees to left/right depending on the direction of the target in your scope. So if they are sailing to the right in your scope, you set the angle to the right, and left you set the angle to the left and such.

Just trying to figure out how to get my torpedoes to hit ALONG the target rather than kinda in the same area :)

[magic452]

You can use the gyro angle offset dial for this but it is so range sensitive that it's difficult. The longer the range the smaller the offset must be. Once you get use to it, it works pretty good. Your example for 4 or 5° would be for very close targets, more like 1 or 2° would be the norm.

If I am using this method I will lock the target and shoot stern to bow -1, 0 and +1° or whatever is needed. At longer ranges 0.5° may be necessary. I do this when I don't want to leave the scope up for a long time.

A better way to shoot a spread is to first take a final range and bearing measurement. Second turn off the PK, unlock the target and move the scope to a positing slightly ahead of the bow and send range/bearing to TDC and then shoot as the ship crosses the wire shooting bow to stern.
The scope is up for a long time so you have to consider the conditions at the time.

Magic

[commandosolo2009]

Is the offset angle dial in the US TDC the best way of setting a torpedo spread?

So, you'd set an offset angle of say 4 or 5 degrees to left/right depending on the direction of the target in your scope. So if they are sailing to the right in your scope, you set the angle to the right, and left you set the angle to the left and such.

Just trying to figure out how to get my torpedoes to hit ALONG the target rather than kinda in the same area :)


You my friend, need Dick O'kane's targeting method (http://www.subsim.com/radioroom/showpost.php?p=652326&postcount=67)

Cheers and, for the love of God, keep the spread dial as it is..

[Daniel Prates]

I too am curious about using spread shots, since as many skippers, I am not used to use this.

Isn't there a simple way to more-or-less use the offset dial? I mean, In a simple way to put it: how much angle (number of degrees) should I offset a shot every, say, 1000 meters or so?

[Rockin Robbins]

No, the real submariners used slide rules not available to us. It was easy for them and difficult for us.

[TorpX]

I too am curious about using spread shots, since as many skippers, I am not used to use this.

Isn't there a simple way to more-or-less use the offset dial? I mean, In a simple way to put it: how much angle (number of degrees) should I offset a shot every, say, 1000 meters or so?

Actually, yes there is.
Say you want to torpedo cruiser X at any range and have all the data fed into your TDC and are otherwise ready to loose death and destruction, but for the spread matter. Observe the angular distance of the target; if the stern is at 350 deg., and the bow at 354 deg., you know the target occupies 4 deg. of arc. So you can shoot your torps -2, -1, 0, +1, +2 for 100% coverage. You could also shoot -1.5, 0, +1.5 for 75% coverage. You get the idea. Notice that the spread is in both directions, not just ahead or behind. This is not a perfect method as it doesn't take into account the reach, turning radius of the torpedos or whether the range is closing or opening, but is a good quick and dirty method.

How much coverage should you use? That depends. The main reason for shooting spreads is to make up for errors in the firing solution. If you are confident in you solution you can get by with little or at least less than 100%. If the solution is shaky (as is often the case), more than 100% is indicated.

Frequently, I am not using the TDC and use a longitudinal spread. This is just a different means to the same end though.

[Rockin Robbins]

That's fine but the tick marks on your periscope are different angular sizes for different screen resolutions. Once you know what they are for your computer, you can do this. On the real periscope, different sets of eyes did not change the angular size of the ticks.:rock:

[Daniel Prates]

Thanks TorpX!

[TorpX]

That's fine but the tick marks on your periscope are different angular sizes for different screen resolutions. Once you know what they are for your computer, you can do this. On the real periscope, different sets of eyes did not change the angular size of the ticks.:rock:

I'm not talking about the tick marks. I mean turning the periscope/TBT and using the index ring with the center wire. That should be good for any resolution (at least I hope so).

[Rockin Robbins]

Yes, that will work fine and eliminate any error-ridden calculations that tend to muddy up the waters and cause misses. In other words, sight the bow on the centerline and read off the heading. Quickly sight the stern and note that heading. The difference between the two is the angular size of the target.

Now you can use that to figure your spread. Lets say the target is 3 degrees long. A 100% spread would start out at -1.5 degrees from the MOT (middle of target) and end at +1.5 degrees, or the other way around according to what your intended result is, maximally or minimally divergent spread.

I generally shoot a 75% spread, so I would go +1 degree, -1 degree, which is really a 66% spread. Close enough for government work!:har:

[Daniel Prates]

By now I have already tried spreading my shots a bit. It's a good tactic, several hits in different places appears to be a deadlier procedure.

However, it only works if you're sure your calculations are VERY correct and the fire solution indeed does bring your torps in the very middle of the ship. Otherwise, If you made some slight errors here and there, you will have, say, 1 hit and 3-5 misses where, without spreading, all torps would hit, even it in the extremity of the bow or stern.

[TorpX]

Spreading your torps is not a "complete" solution. As you've found out, spreading increases your chance of getting a hit, but also increases your chances of missing with some of the torps. If you could be sure of a 100% correct firing solution, you might never need to use a spread. The usual USN method was to use a spread, but not always. I remember reading O'Kane saying once on Wahoo, they fired their last two torpedos on a small freighter, both at the middle. (Morton wanted no cripples.)


Also, I should point out that if you use RFB, you will probably want to use spreads as the damage model works on the basis of flooding compartments, not just a hit point total. :)

[Mescator]

I remember reading O'Kane saying once on Wahoo, they fired their last two torpedos on a small freighter, both at the middle. (Morton wanted no cripples.)

It's a bit unfortunate that the game maxes out of damage zones, makes such tactics a bit counter productive to their real world effects = /.

(I've always wondered what the results of a torpedo sailing in through a existing torpedo hole and detonating INSIDE the ship would be, although i expect something quite spectacular.)

[Daniel Prates]

(I've always wondered what the results of a torpedo sailing in through a existing torpedo hole and detonating INSIDE the ship would be, although i expect something quite spectacular.)

Now imagine that happening to a ship loaded with fireworks.

[Armistead]

We all shoot spreads, but I prefer to use the stad to get everything plotted, then I'll unlock and shoot by the wire forward to rear, other times I set my spreads by changing enemy speed slightly by .5 to 3 kts because of the enemies ability to stop and speed to flank on a dime I react more to that than the actual setup. WIth M18's I tend to use the spread wheel since they can't see the wake.

As stated damage zones are more or an issue with either mod, although RFB is a lil more realistic with NSM. Still, you want to spread your damage out regardless, although you'll get more sinkings with TMO on some ships just by destroying one damage zone. Shot placement can be important, each damage zone can have different effects. Hit a turrent, the mag may explode, hit engines you can slow or stop a ship. Most mods set a weaker damage zone on the keel, so after 43 that's good. The right shot may blow off the ships prop. I once blew the rudder off a Fuso and it couldn't turn, so the group went one way the Fuso went the other and stayed in a straight line for over 400nms until it ran into land.

The game doe's provide internal and external cargo for many merchants such as oil, fuel, ammo, ammo crates, etc...If a merchant is carrying ammo of fuel one torp usually results in a mass explosion sinking the ship. If a ship has ammo or fuel it increases the blast zone. I've sunk one loaded merchant with fuel and the explosion blew up nearby ships many times, which blew up nearby ships. I've seen as many as 6 ships domino explode from using one torp on one ship. If you time it right you can take out many ships, but you only get credit for the one you hit with a torp. Course it's always fun to time a torp to hit a loaded merchant when a escort is passing by, least the escort is gone even if you don't get credit.

[Skubber]

The game doe's provide internal and external cargo for many merchants such as oil, fuel, ammo, ammo crates, etc...If a merchant is carrying ammo of fuel one torp usually results in a mass explosion sinking the ship. If a ship has ammo or fuel it increases the blast zone. I've sunk one loaded merchant with fuel and the explosion blew up nearby ships many times, which blew up nearby ships.

That's really awesome. With which mod?
I really like the idea of ships with dangerous cargo being, well ... dangerous.

Calls to mind the SS Mont-Blanc, which blew up in Halifax harbor – loaded with munitions, the aftermath looked somthing like a small atomic blast.

[razark]

That's really awesome. With which mod?
I really like the idea of ships with dangerous cargo being, well ... dangerous.
TMO or RSRDC, not sure which is responsible.

Earlier this evening, I closed in on a Kasagisan Maru. Great approach, fired a spread of four fish. One missed aft, one missed forward. The other two were duds. Surface the boat, attacked with the deck gun, sunk her, and the explosion took my boat out as well. :nope:

New career time...

[Daniel Prates]

I run TMO 2.1 (and nothing else) and I got damaged being to close to a tanker when it went off.

[Armistead]

That's really awesome. With which mod?
I really like the idea of ships with dangerous cargo being, well ... dangerous.

Calls to mind the SS Mont-Blanc, which blew up in Halifax harbor ***8211; loaded with munitions, the aftermath looked somthing like a small atomic blast.

Cargo is a feature of stock, but I have no idea how much cargo if any stock places on ships. TMO has some, but more limited, RSRD has the most. Cargo can be internal, external or both and can include oil, fuel, ammo crates, tanks, trucks, etc.. When ships carry oil, fuel or ammo is when you get the mass explosions and usually one torp will do the job. If any ships are within the blast radius, they will also explode. In some convoys many ships are loaded with fuel or ammo and often sinking one causes a domino effect, one exploding the other.

Yes, you can easily damage or do your sub in if your in the blast radius, seldom should be an issue shooting torps, but getting in close in a storm and using the deckgun another story.

[JohnnyCarwash]

Hi, I am a longtime lurker here but thought I would finally make an account and contribute something. I am sorry this might be a bit long winded.

I use a formula I found in a torpedo manual online. It is fairly easy you need to know the length of the target, and that is something that takes some figuring, and of course time. This is great method for when you have a long time to set up your attack, even on multiple potential targets!

If you look at the recognition manual it lists mast height. You can take a slip of paper and mark the mast height, then transfer this measurement to the waterline, and "count" how many mast height's the ship is long, in the picture. Simple math gives you an estimate of length (91.4ft tall x 4.3 heights in length is an example). Of course, just an estimate, but it is a start. You are trusting the recognition manual graphic at this point, so take caution.

The formula from the Navy is (lenght/100) x (% of coverage in decimal) x (2000/range) x (sinAoB).

An example for a 450 ft target would be (4.5) x (.85) x (2000/1500) x (1). That is for 85% coverage at 1500 yards and 90AoB. You do not always need the sin to be exact, from 70 to 90 is considered 1:1, 50 to 70 is 3/4, etc. There is a quick reference table for this estimate in the torpedo manual. Remember, this is estimating several things and the game has some other variables that you can not control. If always set up for 90AoB like me, just take that variable out of the equation as it is always 1. If you are in a furball of ships and angles get sharp, just use 1/2 or 1/4 to be safe, it's just a rule of thumb.

So as above you get 5.1, this is the total spread between farthest wings. Divide that number by (TotalTorps)-1, and you get the unit spread between each torp. For a 3 torp volley, rounding, I would shoot 2.5, 0, 2.5. For 4 you might use 2.5, .75, .75, 2.5, remember you are just filling in between what you have determined be the outer two wings for 85%, in this case. I actually use an old slider rule to do all this, as it lets me be a little more "estimatey and roundey" based on how confident I am in my speed/course/range etc.

Remember, coverage % should usually never be more than the overall length of target (> 100%), as that would be considered potential waste of ordinance. I read that comment once in a war patrol report.

It is funny you will find it just as easy that most targets under 2000 yards can be 2,0,2 and you will usually be safe, but for the longer shots a formula really helps.

But have had a lot of success with this method, for shots at all ranges.

[Diopos]

Welcome JohnnyCarwash,
a very interesting and promising 1st post !:up:

.

[razark]

http://i251.photobucket.com/albums/gg307/Nisgeis/SubSim/InGameTSAC.jpg
from here (http://www.subsim.com/radioroom/showthread.php?t=144202). Good for quick, rough figuring, without having to break out a slide rule or calculator, or figuring out sines, etc.

I don't use the version in game. I have it printed out and tacked up on the wall, plus a loose one or two somewhere on the desk.

[Rockin Robbins]

I KNEW Nisgeis' chart would rear its ugly head! That is one amazing piece of work there.

I like to do spreads by shooting a fixed bearing longitudinal spread. That way I've set my periscope at the lead angle and I just aim each torpedo for the part of the target I want to hit: bow crosses the wire, shoot it. Don't move the scope. Beam crosses, shoot it. Stern crosses shoot it. That way you are in complete control of the process and aren't dependent on tired brain cells to improperly process information.

The weakness of a longitudinal spread is that if the torpedoes are seen the target might be able to turn into them and avoid all the torpedoes, since they follow in the same track toward the target. On the other hand, since they follow each other in a single line they might be harder to see. Get in close and it doesn't matter.

[TorpX]

Yes, I have a copy of that chart somewhere, but haven't really gotten around to using it yet.

I like to do spreads by shooting a fixed bearing longitudinal spread. That way I've set my periscope at the lead angle and I just aim each torpedo for the part of the target I want to hit: bow crosses the wire, shoot it. Don't move the scope. Beam crosses, shoot it. Stern crosses shoot it. That way you are in complete control of the process and aren't dependent on tired brain cells to improperly process information.


This is the method I've been using. Since I'm in a S-boat and don't use the TDC, I'm, more or less, forced to do it this way. I've gotten pretty good results though. It like to use less than 100% coverage, and it is easy to do things this way. Using 100% coverage usually means wasting at least 1 torpedo.

The weakness of a longitudinal spread is that if the torpedoes are seen the target might be able to turn into them and avoid all the torpedoes, since they follow in the same track toward the target. On the other hand, since they follow each other in a single line they might be harder to see. Get in close and it doesn't matter.

IMO, the whole "torpedo wake" issue has been blown out of proportion. Is there any way to dial back the torp detection of enemy ships? Not eliminate it altogether, but make it reasonable, I mean.