is it the mod or have I just been lucky before?

[She-Wolf]

hello y'all. The year is 1941 ( christmas) and I am in the Asiatic fleet in charge of a diddy little boat - SS-18. I have left TMO for now ( though will be back as I now understand that my habit of repeatedly saving to the same name was what was causing gremlins) and am trying out RSRDC and RFB, and so far so good - BUT, I have noticed two things that are different.

The first is that I cannot get close enough to a convoy to get a big ship in range ( 3500 yards?) because the escorts pick me up even when I am way out, and the second is that Auxiliary subchasers suddenly seem to have bigger ears than I found to be the case in TMO.

In TMO I would often go up to Yaizu ( plenty of deep water close by) because I could be sure of getting a good haul of merchantmen in that bay, and had a reasonable chance of evading the warships - so I tried it in RFB/RSRDC after I had been set free from my patrol duties, tootled in under cover of darkness, and sat about 5 miles off Yaizu, waiting for dawn. I knew of, and was keeping an eye on a subchaser some two miles plus away, but felt I was safe as the engines were off, I was submerged and it was pitch black. Yet, somehow, he knew I was there - made a beeline for me, and even though I went below a thermal layer and to silent running, I could not shake him off. How did he know I was even there? IN TMO I have had subchasers looking for me round Wake Island and not knowing they had passed within feet, yet this guy seemed to have me pinpointed from over two miles away... I dinna understand it!! ( fun though).

[Webster]

Yet, somehow, he knew I was there - made a beeline for me, and even though I went below a thermal layer and to silent running, I could not shake him off. How did he know I was even there?

its just the game itself, it cheats, plain and simple. there will be lots of times a ship will do that too you and if you watch you will see ships change course and try to ram you because they know your exact position speed and course :06: even carriers and BB but especially cruisers and DD. the best part is no matter what you do they rarely ever miss and can ram your conning tower with sniper accuracy lol.

it is a realism buzz kill for sure since the game would be so much more realistic if they put in some sort of less exact homing in on you and say had a built in error factor to knowing you position but sadly they dont although sometimes they do chase false contacts.

[She-Wolf]

aha... well, I got the little beastie. For some reason the boats seem to 'park up' at night, lying still and silent in the water for hours, which means, if you creep up careful and slow, you can get 'em. Only takes one fish with such a small craft. It doesn't add much to the tonnage but he was a pesky nuisance, stopping me from bagging a merchantman. Grr. Thank you Webster.

[Webster]

glad to help :salute:

even those who have been around a while see something new (and agrivating) about the game sometimes lol

the AI's cheat factor with the game often makes me say out loud "aww c'mon now!"

[Sniper297]

It does cheat all too often, I can't count how many times I've been working on an end-around where the wing escort, altho he hasn't sighted me, keeps edging further and further away from the convoy or task force forcing me further from the track - oh, it's just a coincidence he decided to make a sweep in my direction that changes from a sweep to an independent voyage? :doh:

That said, when they're not cheating there's an art to getting into firing position, the science comes after that. I forget if it was Run Silent Run Deep or the sequel Dust on the Sea, but one character said something like "anyone should be able to hit the target once you get in front of him, the trick is getting in front. A good attack starts with a good approach."

http://img855.imageshack.us/img855/5184/50222049.jpg

Heading directly toward the target is wrong, find out where he's going and get there first so you can be submerged and moving slowly, only needing a little maneuvering to go where you need to be. Move toward the track, not the target.

http://img259.imageshack.us/img259/7272/97311970.jpg

Detection circles for a destroyer - the outer ring is visual if you're on the surface and the lookouts are awake. Yellow is passive sonar, when you're inside that ring you need to be quiet. Red is active sonar, no matter how quiet you are you can be detected, so stay out of it. The range is about 750 yards, so active sonar sweeps a path 1500 yards wide. If the escort is holding a steady course the transparent red areas are the danger zones you want to stay out of, since the red active sonar arc will pass over you if you're in those zones when he arrives.

http://img4.imageshack.us/img4/4986/19110939.jpg

Once he passes ahead you can speed up a little provided the wing escort isn't already so close that he'll hear you, the trick is getting in through any available gap in the screen. In this case I got lucky since the wing escort on this side thought it was a good time to make an outward sweep.

http://img836.imageshack.us/img836/8499/21234169.jpg

Meat on the table, fire at the furthest first and try to time it so all the targets get hit about the same time. After the fish hit I kick out a decoy and go to flank speed and head for the bottom, going straight ahead under what's left of the convoy to cross under - it complicates the problem for the escorts since they'll initially be looking for you on the side the attack came from and if they figure out that you're crossing under they have to avoid colliding with all the merchants. Once under a layer slow down and go silent.

Odd thing about Sugar boats, I've started careers with Mark 10s and assumed that's all there is since the tubes in the S class were too short for the Mark 14. Not paying attention, I noticed that the second patrol starts with a mix of 10s and 14s, which is all wrong. Realistically the S boat has several problems;
1. Mark 10 torpedoes run slower and have less range, ideally the attack range should be 500 to 1000 yards, any run over 2000 yards is unlikely to hit anything.
2. Surface speed sucks, range sucks, sometimes you just have to let task forces and fast convoys go because you'd run out of fuel and the war would end before you finally got in front of them.
3. I don't know if the actual battery recharge rate for S boats was THAT bad, but in the stock game it takes 2 days to recharge 50%. Best use of an S boat in career is to cruise up and down the east coast of Luzon, where you'll find a lot of slow fat merchants steaming alone or in pairs without escorts. Some have deck guns, so it's best to make a standard approach and examine through the periscope when he gets close - if you see a deck gun shoot the torpedo, no deck gun then surface and sink him with your deck gun.

[She-Wolf]

gosh Sniper... I'm impressed....!

[Sniper297]

Let me know how it works out, how impressive a tutorial actually is depends on how successful the reader is after applying it. Obviously with 100% realism it's more difficult since without the map contact update you need two fairly good range and bearing points to plot the target track. And of course the escorts are aware of the limitations of active sonar so the good ones weave back and forth across the track line to broaden the danger area.

The principle remains the same tho, don't move toward the target since a sub underwater can't move that fast, move to where the target is going to be and let him come to you. Ideally you should be facing the track at a 90 degree angle, 1000 yards from the track when the target reaches the firing point.

[TorpX]

Nice presentation. How long did you say you taught at the Naval Academy? :)

[Sniper297]

I cheat, I have god-like powers from all the RPG games I play.

http://img600.imageshack.us/img600/7376/73936525.jpg

Actually it's a lifelong passion as strong as trains for me, my Dad took me to the Chicago Theater to see Run Silent Run Deep when I was a kid and I always wanted to be a submariner. Consequently I read every submarine book I could lay my hands on as soon as I was old enough to read.
Don't ask how I ended up in anti-submarine warfare instead, it's a long story involving alcohol and a Navy recruiter who had billets to fill. :doh:

[Sniper297]

I suppose I should add this - the original poster stated;

I cannot get close enough to a convoy to get a big ship in range ( 3500 yards?) because the escorts pick me up even when I am way out

I'll be covering what some people will consider obvious, but a common n00b mistake;

http://img19.imageshack.us/img19/8963/61454823.jpg

There's the enemy, head toward him and speed up!

http://img248.imageshack.us/img248/9964/97970091.jpg

But that's not gonna work because he's moving, not only will he be somewhere else when you get to where he is when you start, the high speed running will attract attention and deplete batteries. A surface attack at night is difficult to pull off and requires ideal conditions, any submerged attack should never be done from the side or behind.

http://img834.imageshack.us/img834/3451/83619652.jpg

Instead you stay outside the visual detection range of the escorts, turn parallel to the target's course, go to full speed and perform what's called an "END-AROUND" to get in front without being seen.

http://img560.imageshack.us/img560/8644/80157489.jpg

It takes time and patience but the idea is to pass him then move toward the track when you're ahead of him, don't get too close but don't get so far away that you lose contact either.

http://img850.imageshack.us/img850/1672/60357817.jpg

This is much harder with map contact updates off, but you want to stay at least 5 miles away from the nearest escort all the way. So when you arrive at the track you should be 5-10 miles ahead of the convoy/task force and ready to submerge, maneuver to a good firing position, and go silent before he gets there. The previous clipboard bragging I did different from the usual convoy, there were two columns of battleships and carriers about 1000 yards apart so I postioned my sub between the tracks facing parallel instead of perpendicular. Then I went down to find the layer, went 50 feet below that (the BT detector like the depth sensor is on the keel, if the thermal layer is at 160 feet you have to go down to 210 feet so the whole sub including conning tower is under the layer) and watched the sonar. As soon as the lead escort passed I rose to periscope depth and started firing bow and stern (Sargo class, four tubes at each end) at the furthest targets first, then the closer ones. The leading ships in both columns had already passed when periscope depth was reached so the sequence was last left, last right, spin the scope around and fire at first right and first left, then back around to third left and right, by which time the second in each column was past me close aboard so pop one at each. Shortly after all hell broke loose SIR! and a couple of the battleships required another fish. Next is get back below the layer and go quiet, discretion is the better part of valor.

:arrgh!:

[She-Wolf]

Sniper dear heart, I see all that you say makes perfect sense and have no argument with it. When in a Porpoise or equipped with the later torps I have had some success, now and then, to 'bag a biggie' using a creep toward and stay quiet and on the fringe until the escorts are passed strategy. However, can I ask whatI ought to have done differently in this mission? I was starting a new career based in Manila in an SS-18 with torps that only have a range of 3500 yards. I was cruising up the Luzon Straits, minding my own biz, on the way to my patrol area when I saw a huge battlefleet coming straight toward me. With eyes like saucers I waited and watched until I could pick out which would be the best target and how I needed to place my sub for a 90 degree shot - but of course I would have to be a lot closer in with such short-range torpedoes - so I started edging forward at 1/3rd with the intention of getting close enough and then swinging round as the ship passed. Well, never got that far as the escorts knew I was there long before I got into range of the big boys, and started dc'ing my position. I tried several times,going back to the save and attempting a different angle but each time the escorts found me and I eventually retired and watched my prize steam away untouched. Should I have gone deep? Should I have switched off engines ( but then how would I get close enough to attack)? I am sure a REAL skipper would have done something, but I snuk off with my tail between my legs....
ps this is in summer 1941

[Sniper297]

If it was summer 1941 you'll be explaining at the court martial why you thought it was a good idea to declare war on Japan 6 months before Pearl Harbor. :doh: Actually I don't know, S boats are a serious handicap to start with, the AI does cheat in the stock game sometimes. Without map updates them drunken lubbers on the deck watch repeatedly lose sight of an escort then report him as a new contact as he weaves back and forth, but don't think it's important to mention "uh, skipper, that tin can I reported earlier is getting closer now". 100% realism is not realistic simply because any lookout, sonar or radar operator should know enough to not report the same contact over and over if he's weaving back and forth in and out of contact range, it's ludicrous to keep reporting the same target as a new contact. Then the damned thing turns toward you long enough to see you, goes to full speed on a collision course, but since he's been in sight the whole time none of them scurvy dogs think it's important enough to mention it so you're completely unaware until the first shell hits. The whole crew needs Ritalin for that ADHD.

The mega mods like TMO might be different, I haven't tried any of them yet but probably will over the next month or so just to see what all the fuss is about. Lacking other info my guess is unless it IS a cheat they already detected you earlier than you thought, so your earliest save was already too late. One trick you could try is note the coordinates of that mongo task force then go back to a save long before you encountered them, proceed at speed to that same spot to see if they show up consistently. I've done that in the stock game a number of times, most would consider it cheating but I prefer to think of it as better intelligence reports from the purple machine boys.

http://img688.imageshack.us/img688/9862/60332607.jpg

Contact report, 600 miles away, by the time I get there he could be anyplace. So save the game and accelerate time while just sitting still, see where he goes.

http://img21.imageshack.us/img21/5608/15100902.jpg

New contact report 2 days later, note the position 16.5 N 116.8E. Reload the save game, mosey on over to that spot and wait two days for him to show up.

http://img802.imageshack.us/img802/9216/47265319.jpg

Again that's with a Sargo and I was lucky enough to sink 6 ships with 8 shots, if it was an S class I'd target a single battleship as close as I could get with a spread of four and call it good. Problems with saving and reloading when they're right on top of you, the torpedo settings and gyro angles do not save, so don't even bother saving the minute before firing since you'll never have time to set it all up again. Be set up and ready directly in front of them before they arrive and save it there.

[Wolferz]

That early war task force that you want to hit with your old WW I tub is headed for Manila to invade the joint. So, lets's cheat a little with some intel from the coast watchers we dropped off in Japan. After you debark from Manila, head straight up the western coast and park yourself in that western Luzon bay and wait for them to arrive. There are numerous troop transports and a few juicy cruisers to go along with a plethora of DDs.
Good luck.:D

[She-Wolf]

thanks for the tips boys - useful because in previous careers I have started from Pearl Harbour and with a more-up-to-date boat and torps, S-boats and Asiatic fleet is new t me :)

[Sniper297]

Worst trouble with Pearl is it takes forever to get anyplace, you might as well be starting in Nebraska for all the time it takes to get to the patrol area. Asiatic sucks after Java gets taken, so I hacked something with the mission editor - i forget what - to place a tender and some destroyers at Mios Woendi and made that the new home port instead of Freemantle after Java goes down.

Just finished downloading TMO 2-5, I'll try a Sugar boat in that and see if I can duplicate the AI cheating.

[She-Wolf]

Yes - the long trek to and from PH - that was why I changed.

[Sniper297]

I'd upload the new base mod if I could remember which files I hacked for it, but I'm a senile old geezer and can't remember for sure what I had for breakfast. :06: I should probably do a better one more centrally located anyway if I can remember how, secret allied sub base in Formosa? :|\\ Enabling TMO, off to start an S-boat career, see if I can find Bungo Pete and teach him who's the BOSS! :arrgh!: (Famous last words?)

[Wolferz]

S-boat career, see if I can find Bungo Pete and teach him who's the BOSS! :arrgh!: (Famous last words?)


The last words of Captain Sniper297...:03:
*Transmission garbled*

[Sniper297]

Bungo Pete will have to wait until spring, winters here in Wisconsin are brutal and $400 per month heating bills leave zero left over for DLC. Since both versions of TMO I've tried apparently require SH4 1.5 and I have SH4 1.4, they won't work at all for me.

[BigWalleye]

Wisconsin, eh? Nort' or Sout'?

[Sniper297]

Central, little tank town about 50 miles south of Wausau. I'm originally from Chicago but after my Dad and little brother died I had no family left there, so I moved up here where most of my kids and grandkids are. Beautiful in the summer, glaciers in the winter.

[BigWalleye]

I'm north of Eau Claire. Hey, Winter's not so bad. At least there are fewer mosquitoes!

[Sniper297]

I prefer mosquitoes, you don't have to shovel them.

http://sphotos-b.xx.fbcdn.net/hphotos-prn1/155570_160190010691954_1215101_n.jpg

[TorpX]

However, can I ask whatI ought to have done differently in this mission? I was starting a new career based in Manila in an SS-18 with torps that only have a range of 3500 yards. I was cruising up the Luzon Straits, minding my own biz, on the way to my patrol area when I saw a huge battlefleet coming straight toward me. With eyes like saucers I waited and watched until I could pick out which would be the best target and how I needed to place my sub for a 90 degree shot - but of course I would have to be a lot closer in with such short-range torpedoes - ...
I can't give you a specific how to, or critique your plan, but I would like to lay out a few quick general points:


The Mk 10 torpedo range of 3,500 yds. is reasonably adequate. The odds of getting hits at longer range would not be very good; at least on fast moving targets.
You don't need to line up on a 90 degree track. Against difficult targets, I would consider anything between 60 and 140 good. Forget what you may have learned in SH3; it doesn't apply here. The Mk 10's will detonate well at any angle.
Trying to sink well escorted IJN fleets with a S-boat, is a David - Goliath contest. Very few capitol ships were sunk by S-boats. In fact few were sunk by USN subs of any sort before 1944.

Really, if it was easy to sneak up to a powerful IJN fleet and devastate it, and escape, the game as a simulation, would be pretty much worthless.

[Sniper297]

Well, I just installed TMO 1.4 yesterday so I haven't had time to check it out, but in the stock game how easy it is depends on how well I'm positioned before the task force arrives. To allow for errors I generally get set up directly on the track, check when the lead destroyer is five miles away and confirm the exact location of the track, then start moving to 500 yards off the track while diving to 200 feet. Rounding off, a nautical mile is 6080 feet, I just call that 2000 yards. A task force is usually moving at 12 knots so it takes 5 minutes (60 divided by 12) for it to cover 1 mile. A Sugar boat takes about six minutes to get from periscope depth down to 200 feet, then 3 minutes to get back up to periscope depth. So when the range to the lead escort is 3000 yards he'll be over you in 7 1/2 minutes, and you'll be in his active sonar arc in about 7 minutes, even if there's no layer the slant range of the active sonar makes it much more difficult for him to pick you up at 200 feet, so start heading down there as soon as he's within 3000 yards.

Follow him on sonar (he'll be the closest unit so the sound man can do that) then order periscope depth as he passes overhead and turn toward the track. If the lead ship in the column is 1000 yards behind the lead escort he'll cover that 1000 yards in 2 1/2 minutes so you'll be looking at a stern shot, best bet is to ignore him and set up on the second or third ship in the column.

Another tip is to position the sub at 200 feet facing the same direction as the task force, so they're coming at you from behind - that places you with the smallest aspect for the sonar. Why facing away from them instead of toward them? It avoids "chasing the angles", if you're facing north and they're going south, you start turning toward the west while they're still moving south, they're changing angle faster than you can turn. If you're facing south and turning west his position is approaching the 90 degree angle instead of running away from it. An exact 90 degree angle torpedo track is ideal, but when you're close in anything from 30 to 150 with up to a 30 degree gyro angle will work, the main thing is the closer you are the harder it is for them to avoid getting hit.

[She-Wolf]

You don't need to line up on a 90 degree track. Against difficult targets, I would consider anything between 60 and 140 good. Forget what you may have learned in SH3; it doesn't apply here. The Mk 10's will detonate well at any angle.
Trying to sink well escorted IJN fleets with a S-boat, is a David - Goliath contest. Very few capitol ships were sunk by S-boats. In fact few were sunk by USN subs of any sort before 1944.





thank you TorpX, I don't feel quite such a hopeless kaleun now :D

[Armistead]

The 90 degree track is often the most dangerous, can put your broadside open to an escort.


I've sunk numerous capital ships with an S-boat....

[She-Wolf]

Armistead, interesting. I DID get the 90 degrees thing from SH3 as TorpX surmised, and it seems sensible to me, giving you the broadest chance to hit the target, and then you sink and skedaddle before the escorts pounce. I am impressed that you have knobbled biggies with the S-class.. I have just found another convoy and next time I go in I will try to put the accrued wisdom of you cleverer chaps to good use!

[Sniper297]

Well, again 90 degrees is the ideal attack, if someone sees the wakes or your periscope or an escort picks you up on sonar everyone starts speeding up and turning and blowing whistles and flashing signals and firing star shells all over creation. With a sharp angle the target speeds up, slows down, turns aside and the torpedoes miss. With the beam attack at least one fish will hit him somewhere, aft of center if he speeds up, forward of center if he slows down or turns. Standard doctrine was to fire four fish from the beam, one forward and one aft of center, and two more aimed to deliberately miss the target ahead and behind. That way whatever he does he's gonna take at least one torpedo someplace in the hull. At close range it doesn't matter as much, at 500 yards there's no time for dodging it, even a mark 10 at 36 knots will hit him in less than 30 seconds from that range. I often use my stern tubes to sink a destroyer, when he's coming straight at me from behind I wait til he's at 700 yards, fire one straight at his nose then one to miss right and the third to miss left so whichever way he turns he's toast.

Main thing is whatever the angle closer is better, as long as the fish has at least a 400 yard run to arm the closer you are the better the chances of a hit.

Once the first fish hits or the destroyers start whooping and pinging the jig is up, they KNOW you're there so there's no sense trying to be stealthy NOW, go to flank speed and get closer to your next target before firing, then hit the J key and dive down to 200 feet, don't slow down and go quiet until you're deep or below a layer.

[She-Wolf]

hmm, yes.. I haven't usually gone to flank speed and attacked when I've been sussed. Will try that next time it happens. Just been looking at one of the vids that ColonelSandersLite has linked to on the VideoPlayThrough thread... gosh.. so THAT's how it is done 'properly'! My efforts are much more 'rough and ready'.

[Armistead]

Depends if you're attacking a large convoy or small. The problem with sticking to a 90 degree attack is it often exposes your broadside to the enemy, making you an easy sonar target. You may get your attack off in time, but you may get pounced. If you use TMO or other mods that increase the AI or crew ratings, you want to stay as narrow as possible to the nearest escort. I don't use any method that forces me to stay on a set track, I try to come in from the front and I will constantly helm to keep my nose to the nearest DD. If you use mods like RSRD you'll often run into large convoys, so instead of shooting from a flank, you'll want to helm right in the middle of the convoy so you can shoot bow and stern torps at targets at the same time. Being in the middle of the convoy often causes escorts issues with dodging merchants to get at you.

It also pays to know what cargo is on the ship by looking through the scope, couse you have to learn to ID it. If it's fuel or ammo, one torp will explode the ship and take out any ship near it. I often try to time my hits when an escort is close to a loaded merchant, so the explosion will take him out as well. I've timed it to where I've taken out 6 merchants with one torp and 3 escorts as well. Problem is you only get credit for the ship you hit with the torp, but in those large 30-60 ship convoys, helps to get rid as many escorts as possible.

If you want to get good at the game using hard mods and realism, you'll need to learn several shooting methods and apply the best one needed based on the group you're attacking. For instance with TMO/RSRD Formosa is a great hunting area for large convoys in 44 but most the escorts are veterans and most are Type A-D, carrying 6 Y guns, double roll offs, etc...Many convoys run the shore line, so water is shallow, one mistake, you're dead.....not to mention the area is mined and if escorts spot you, planes come from all around to join in on the hunt dropping charges.

[TorpX]

People seem to be hung up on the 90 deg. thing. 90 degrees is not the optimum track angle.

Optimum TTA = 90 + arcsine (target speed / torpedo speed)

so, for
Mk 10 and 9 kt. ship_________ 104.5 deg.
Mk 10 and 12 kt. ship________ 109.5 deg.
Mk 10 and 20 kt. ship________ 123.7 deg.


This torpedo track angle gives the greatest error tolerance with respect to target course unknowns. This is not me saying so; this was taught and used by the USN.

[Sniper297]

You're thinking of the angle off. If you have a ship passing from right to left and wait until the periscope crosshair reaches zero, the torpedo track will not be 90 degrees. You fire when the crosshairs are at 15 degrees right (for the Mk 10 and 9kts) and it should impact when the crosshairs reach zero, assuming the ship continues at the same speed and direction during the entire torpedo run. Before the replacement of the contact exploder steel firing pins with aluminum pins the straight on 90 degree shot resulted in more duds, so a 30 or 60 was actually more reliable. But again the sharper the angle the better chance the target has of avoiding the hit by turning toward or away from the track.

[TorpX]

No sir,

I'm talking about the optimum track angle. If you don't believe me check out the Submarine Fire Control Manual:

http://hnsa.org/doc/attack/index.htm

Scroll down near the end. On plates XVII and XVIII there are two charts that show a graph for the deflection angle vs. track angle. The optimum track angle (greatest error tolerance) is at the point of the graph where the deflection angle is a maximum. This is so because at the maximum, the slope is zero or near zero, and errors in the track angle (because the target's course is not precisely known) have the least effect.

[Sniper297]

I think we're talking about the same thing calling it different names or something, the numbers you're posting are the lead angles which will result in a 90 degree torpedo track.

http://img46.imageshack.us/img46/4848/58818785.jpg

If you're exactly perpendicular to the target track you don't fire when the angle on the bow is at 90, you fire before it reaches 90 so it will be 90 when the torpedo arrives since both the target and the torpedo are moving.

http://img26.imageshack.us/img26/3158/39630712.jpg

That's for a mark 14 rather than a mark 10, so the lead is a little less due to the faster torpedo speed. The lead angle is 13 degrees and the AOB is about starboard 80 when the gyro angle on the TDC hits zero, that's when I fire.

http://img692.imageshack.us/img692/2821/72751983w.jpg

Since the target moves during the torpedo run, the fish hits when the periscope angle reaches zero, angle on the bow is 90.

Again it's not necessary or even desirable to be that exact, the important thing is whatever hits the target. Got two or three targets in line ahead I let the first one go by, fire at the last one which will hit at something like a 40 or 50 degree angle, then the first one which is now a stern chase which might hit 20 or 30 degrees abaft the beam, then the middle one which will hit close to 90 degrees. When shooting multiple targets the timing to get all the fish to hit within a few seconds of each other is more important than angles, since after the first explosion the other targets are not gonna keep a steady course so you can line up an exact broadside shot on each one in turn. With a single target at longer range the closer you can get to a 90 degree track the more difficult it will be for him to dodge it. Again, closer is better.

[magic452]

Nope TorpX is talking about something entirely different.

What you have there is a vector analyses attack.
Vector analyses attack can be done from any approach angle not just 90°
If you have good data it's very accurate but does not account for any change in the target course or speed if it tries to evade.
A spread will do this. Put one across the bow. This will make the target commit to a course of action, slow down, than adjust the remaining shots accordingly.

What TorpX is talking about is the optimum torpedo track angle.
That is the torpedo track angle that gives the target ship the least possible number of options to evade your torpedo. Or in other words gives you the best tack angle to hit the target even if it starts to evade. It will always be greater than 90°

Stock DDs are as dumb as tree stumps. With TMO you go trying 90° attacks form close range I predict a very short career, even TMO 1.4 much less 2.5.

A much better tactic is to track the convoy and get a better shooting situation such as night or bad weather. Much less chance of being seen.
Pick two targets and shoot one low speed and one high, timed right you get all impacts in quick succession and no time for the targets to react.
An approach angle of about 70° works just fine and you have much less chance of being detected. You still shoot at a low gyro angle, close to zero.
High gyro angles means that you have less tolerance for range or speed errors. True that you have a smaller target to shoot at but a better chance of living to tell about it.

Magic

[ColonelSandersLite]

RE Attack angle:

There's another hidden advantage to a sharp or obtuse attack angle as well. Suppose you fire at 1000 yards to the impact point on a 45 degree track angle. Your subs distance from the actual track is 720 yards (give or take a small amount) - 280 yards close than you would have been had you fired at a 90 degree angle. This means that you're also 280 yards further away from the wing destroyers track, which can be significant.


hmm, yes.. I haven't usually gone to flank speed and attacked when I've been sussed. Will try that next time it happens. Just been looking at one of the vids that ColonelSandersLite has linked to on the VideoPlayThrough thread... gosh.. so THAT's how it is done 'properly'! My efforts are much more 'rough and ready'.


Thanks!

[Sailor Steve]

Also remember the firing-pin fault on early Mk 14s. Ninety degrees was the angle most likely to cause a failure to detonate.

[TorpX]

Sniper,

I don't want to get completely lost in the technical stuff, but you (and others who haven't already seen it) should look at the Submarine Fire Control Manual. The graphs explain it better than I can. I didn't think too much about this aspect of fire control before someone posted the graphs. After studying them a while, I came to appreciate their value.

The point I'm trying to get across is that the "90 degree attack" is not essential, or even desirable, for a successful torpedo attack. But many who play the game, consider it almost mandatory, because they have been "taught" this from others. However, there is no mathematical/logical advantage to it. The USN "did the math" and had better methods.

[twm47099]

Sniper,

I don't want to get completely lost in the technical stuff, but you (and others who haven't already seen it) should look at the Submarine Fire Control Manual. The graphs explain it better than I can. I didn't think too much about this aspect of fire control before someone posted the graphs. After studying them a while, I came to appreciate their value.

The point I'm trying to get across is that the "90 degree attack" is not essential, or even desirable, for a successful torpedo attack. But many who play the game, consider it almost mandatory, because they have been "taught" this from others. However, there is no mathematical/logical advantage to it. The USN "did the math" and had better methods.


I agree. The only advantage of a 90degree approach (with 0-gyro) is that you can easily hit multiple targets (I've done 3 so far) at exactly the same time. With a zero gyro angle since all shots follow the same track, it can only be done with a 90 degree approach. That is because in a convoy ships in the same row of different columns all cross the torpedo track at the same time, but at the firing point they are staggered with the ship in the furthest column crossing the firing wire first. The slower the torp speed the greater the lead angle and the greater the separation between ships at the firing point. I usually try to get between columns and fire at two ships from the forward tubes and one from the stern tubes.

However, I usually find a 60 to 75 degree zero-gyro attack is better for a number of reasons described by others above. I will determine the approach angle depending on the arrangement of the escorts in each situation. I will try to get as far as possible in front of a convoy so that I have time to set up between the columns. That gives me my best choice of targets and usually limits exposure to escorts. Also my usual escape route after firing is to head for the next ship in the convoy column (at 2/3 ahead or standard) just ahead of me and go deep under it. That usually gives me time to get under the layer and far from my firing position where I switch back to silent running. The only problem is that I don't get to see the results of my attack first hand.

Note that the 3-at-once attack is more of an exercise in geometry and a 'can-I-do-it?' thing rather than a historical simulation. I'm not even sure how many submerged attacks in the Pacific were actually attempted or made from within a convoy (torpedo runs of 450 to 700 yards.) But it is a puzzle and a challenge, although probably not one a real commander would attempt in life or death situations.

I am going to give the 'greater than 90 degree' approach a try to see if that helps with accuracy on longer range shots.


Tom

[Armistead]

Sniper,

I don't want to get completely lost in the technical stuff, but you (and others who haven't already seen it) should look at the Submarine Fire Control Manual. The graphs explain it better than I can. I didn't think too much about this aspect of fire control before someone posted the graphs. After studying them a while, I came to appreciate their value.

The point I'm trying to get across is that the "90 degree attack" is not essential, or even desirable, for a successful torpedo attack. But many who play the game, consider it almost mandatory, because they have been "taught" this from others. However, there is no mathematical/logical advantage to it. The USN "did the math" and had better methods.


Totally agree! If you use any mod that increases the AI or crew ratings, th 90 attack is your worse option.....IMO.