Realistic attacks!

[siber]

Hi guys and gals!

I was wondering; how many torps would a real life captain fire at a target? Would that number change depending upon whether the target is alone or in a convoy, or merchant or warship?

To be honest, I feel that the 1 torpedo per ship rule results in vastly unrealistic tonnage scores. Why are we all so good here, but (in general) uboat's averaged only few ships sunk each? What's the unrealistic factor? The number of torpedos fired in the salvos?

At the moment, in my Type IIA (Jan. 1940) I'll generally fire 2x spreads of two torps in a patrol, saving one torp for the return journey. However, how would I fire torps if/when I upgrade to a VIIB to be faithful to real life tactics?

More torps fired = better chance of hitting, but fewer salvos available.

[flakmonkey]

The one ship, one torpedo rule only applies if you are Otto Kretschmer for everyone else it varies depending on the ship and weather conditions.

Generally i fire a full salvo of 4 if the target is 7000 tons or more so i can be sure of at least 1 hit, this helps especially in rough weather when your range/AOB calculations may be a little off.

I seem to recall real life patrols of 80`000 tons or more so if your aiming is up to the task you can cartainly acheive realistic tonnages.

+ Although it can take DAYS for a large ship to sink with only 1 hit, if it sinks at all! So its probably best to be sure you sink it on the first attack and fire more than one fish.

[Brag]

Sinking 2 - 3 Ships in a convoy attack is realistic enough. Historically, the lower tonnages were not so much due to misses or pumping large loads of torpedoes out, but lack of contacts. IN SH3 finding targets is easier than in RL. Usually we return to base with empty tubes and plenty of fuel left. Historically U-boats returned short of fuel and torpedoes left in the tubes.

So this is a question of playability vs historical accuracy.

Now do what Onkel Neal says to do on this thread:http://www.subsim.com/radioroom/showthread.php?t=129239

[Grayson02sept1980]

anything above 5000 gets at least 2 torps...

anything under 5000 is not worth it ... nah! if I stumble accross a single one and if it is a little 2000t sahiop I shoot it with one and hoping/praying it is enough

In convoys I pick the two biggest with my fron tubes 2per ship and the third ship also is a big or I take two smaller ones (type IX I have now)

6 torps on 3-4 targets not more.

[melnibonian]

It depends on the target really. If the merchant is alone one torpedo was usually used to wound it or stop it before it was finished off by gun fire (early in the war). During convoy battles the usual practice was to fire a salvo of two torpedoes per target to ensure a hit and to maximise the chances of a kill. Generally speaking though each Captain had his own style and based on their experience they were taking the choice on how many torpedoes they would use.

[Keelbuster]

Two per target makes sense. You can straddle the ship's midline and thereby hedge your bet on its speed (if you're slow you turn it into a midship + stern hit, if you're fast you turn it into a midship + bow hit). Two hits almost always kills a ship. If it's bigger (like a BB, or an aircraft carrier) I'll give her three. If I'm really unsure of the speed of a BB (which sometimes happens because they go so fast) I'll give her four, spaced evenly along her. In the IX, two per target is great because it means 3 ships, almost certainly destroyed, per convoy raid. In convoys, it's not worth shooting one torp at a target because if it takes her days to sink, you have to hang around to make sure, and thus lose distance on the rest of the convoy. You want to inflict sudden destructive hits on all targets, and then start the overhauling maneuver. I don't really know what they did in real life , but I sort of imagine that having played the game for long enough on high realism, you'll basically end up behaving like a real Kaleun.

[Captain Nemo]

This is an interesting thread. From what I have read, generally speaking two torpedoes were normally fired at a target by U-Boat captains to try and ensure a hit and a kill. In comparison, British submarine captains tended to be more generous with their torpedoes firing four to six at a target. Deck gun actions by British submarines, especially in the Med, were also quite common.

Nemo

[Ivan Putski]

I was on my 22nd patrol, June 1942 in area AK62, the sea was very heavy, winds 15 meters per second when I contacted a merchant at long range. It was dusk, I usually don`t bother with attacking ships in that type of weather conditions, waste of eels. I had been out for 14 days without a sighting, so said give it a go. I had a milch cow not to far from my position, so I plotted the merchants course, and set up for an attack, reching the intercept point I went to 22 meters, and picked up the Merchants screws, he was close. Reaching PD, I was surprised to find two American Granville-Type Freighters.

At that point I had an almost perfect AOB on them, range close around 600 meters, set depth 2 meters under their keel, and gave the trailing one 2 eels, made slight adjustment, and fired 2 at the lead freighter. All 4 mags detonated under their targets. The rear freighter was exploding, the lead was ablaze, and got off a couple rounds at my scope, which I returned to it`s armor housing. It took a little over an hour, but the lead freighter finally went down, and BDU was happy. Puts

[SmokinTep]

Anything over 3k tons, I will usually fire 2 at it.

[Canovaro]

I fire 2 at small ships and 3 at big ships. Always inpact and 3 meters deep. I'm a boring kaleun

[Uncle Goose]

Real U-boat captains knew a lot about merchant ships and could easily spot the weak points on those ships, their aim was to send the ships to the bottom using only topedo's. The reason for that is simple, you could indeed use 1 torpedo for 1 ship but this meant you had the change the ship would sail futher even with the damage or that it comes to a dead stop and you have to finish it off with either another torpedo or use the deckgun. Using a deckgun was a risky business, the boat wasn't crashdive ready and if a destroyer (or even worse, a plane) popped up then you could really be in serious problem and lose the boat and the crew. That's why most captains tried to finish the ships off with torpedo's rather than to have them shelled and expose themselfs to hostile retalliation. Especially later in war the risks to use the deckgun increased dramaticly.

[Hitman]

From the U-Boot Commander's Handbook (Official Kriegsmarine publication, revised 1943, ful text here http://hnsa.org/doc/uboat/index.htm) :

Section IX
Use (Expenditure) of Torpedoes.
391.) Every possibility of attack must be used quickly and resolutely. In most theaters of operation, the opportunities of hitting with a torpedo are rare. Do not, therefore, economize in torpedoes when attacking.
392.) The torpedo must always be ready for action at shortest notice. Always be prepared for unexpected opportunities of attack. A neglected opportunity will not recur.
In foggy weather and bad visibility, the tubes should be ready flooded. If necessary, they should be flooded via the mouth flaps.
393.) As far as the supply of torpedoes allows, several discharges, in the form of multiple shots (double or three-fold shots) should be directed against worthwhile targets, even at short range and when the aiming data are not in doubt. In this case, all the torpedoes should hit the mark, in order to ensure the annihilation of the enemy. This means that the torpedoes should be fired at different parts of the target.
394.) If the range is over 1,000 m, or if there is uncertainty as regards the aiming data (high speed of the enemy), several torpedoes (2, 3 or 4) should be released on the "fan" pattern. The idea is to make sure of one hit. It is better to score only one hit than to miss the target with each of several consecutive shots.
The target should therefore be covered by aiming at the boundaries of the area of dispersion on the target, i.e., the shots should be spread by the width of the dispersion area in relation to one shot aimed on the basis of the estimated data (if 2 or 4 shots are fired), in relation to an imaginary middle shot).
395.) If a final shot is necessary to sink the damaged ship, remember that the number of misses at the kill is proportionately greater than in firing during the attack.
a) At the kill, steer the submarine ahead of the stationary target, in position 90 at range 2,000 to 3,000 m, and approach slowly, carefully keeping the course, to find out whether the enemy is still making headway. When the change of bearing has been measured, the speed of the target should be set on the director angle of the computer, or the enemy should be finished off by the bow or stern torpedo attack proper. The speed of the enemy should be taken into account in determining the displacement of the marking point on the target.
b) Go in as close as possible, range under 1,000 m. On moonlit nights and during the daytime, submerge once more and attack underwater at 400 to 500 m.
c) If, in remote sea areas, an early arrival of enemy defence forces is not to be anticipated, the final shot should not be precipitated. Many ships sink only after 2 to 3 hours.
d) If enemy anti-submarine forces are sighted (naval or air), the final torpedo should be fired at once.
e) In the circumstances described under c), it should be ascertained whether the target can be destroyed by gunfire, instead of by the final torpedo. See also No. 277.

[antikristuseke]

When im confident in the data i have gathered I fire single torpedoes at targets less thant 4000 tons, 2 torps at anything over that but under 10,000 tons, and 3 or 4 at larger targets, depending on the descision i make at the time.
In rough weather I never fire less than 2 torpedoes at a target due to the difficulty in obtaining accurate data about the target.

[siber]

So, combining Brag's and Hitman's comments, to play realistically, I should use salvos of 2-4 torps per attack and realise that SH3 provides far more targets than would have appeared in real life (but I presume this is hardcoded?).

Cool. I was just wondering whether my tally of one-to-two ships per patrol in my Type IIA was realistic, and whether I should be using single torps or salvos when I move up to bigger boats.

If I may ask one more question: When firing two or four torp salvos, how do you decide the spread angle? Three in a salvo means one straight down the middle, but two/four means that there's not a 'centre' shot...

[Keelbuster]

Originally Posted by siber

If I may ask one more question: When firing two or four torp salvos, how do you decide the spread angle? Three in a salvo means one straight down the middle, but two/four means that there's not a 'centre' shot...

Here's my take on it. Don't worry about firing an official 'spread' a la TDC. Use your Periscope/UZO to do the angle for you. If your range is right or close, then by aiming at the very bow of the ship, and the very stern, counts as a spread. If you're really unsure about the target's speed, aim even ahead of it (or behind it). I almost never do this. For ships travelling slow and medium speeds, the length of the ship makes it cover a good spread angle. Thus, sending a shot to the bow and a shot to the stern counts as an effective spread - as I said earlier, you may get both, you may get one (if you pegged it as too slow or too fast). Don't worry about having one 'straight down the middle'. Technically, the one straight down the middle is your best estimate of the target speed. For a small merchant, who's length is relatively short, it's wise just to fire a single torp straight down the middle - this is your best chance of hitting it.

There is an advanced method that i've started using. I'll get a minimum estimate - like - I _know_ for sure, that the ship is going faster than 6kts, but I don't have time to get a better estimate. So I'll set her for 6 kts, then aim a center shot, and a bow shot. That way, if he's doing 7 or 8, the center will hit stern and the bow will hit center. If i'm really unsure, i'll put a third shot in front of the ship, just for the weird chance he's actually doing 10. This kind of uncertaintly rarely happens for slow and medium ships because the speeds are so tightly bounded (like, your sonar man will tell you if it's slow or medium, giving you a 2-3 kt margin on the actual speed). If it's a fast ship, then it gets tricky because fast is everything > 12 (i think). So, you set it to your guess, then fire shots ahead of the ship to cover the different possibilities. Another way to do this is to keep the aim centerred, then change the speed in your TDC for each shot, to account for each possibility. I do this sometimes if one misses completely - jack the speed up by at least two knots and fire another - it usually hits.

The main message is, you don't need to use the TDC spread. It's not faster, and you don't really have to compute the angle because the UZO/peri does it for you. Now if you want to, for realism reasons etc, then, well, someone will have to walk you through the trig problem you can solve on your map.