Ideal range for sonar only attack on a lone merchant

[commandosolo2009]

Hello skippers,

I'm in a bit of a dilemma here. Just a few moments ago, after 3 mission reloads, I fail to deliver but 1 out of 12 eels to a stupid merchant (yes 12 since 4 of them multiplied by 3 mission saves to just before firing.


The story: While I was inside Shizuka (just west of Tokyo), I found this very ship (a Large Old Split freighter), worth 8k+ tonnes. Problem is, the devs got the spawn inside the grooves or comb-like channels, that you have to be dead on for a magntic boom, which, means that I literally have to be under a Subchaser, in shallow waters, to get the other ships with a rear shot.


So, I decided "hell, we'll get them sooner or later, then, in fury, shot an eel to the chaser, and left with hate gushing out of my eyes..



So, couple minutes later, while sailing to open waters, I get 2 chasers on my back, so I floor the poor electric engine, to get to echolot 119 meters, I order a full stop, pause loading on tube 4, and dive to 100 meters.


I wait for like 6 hours, not getting a single contact, then on my way up, I notice this sonar contact, which sounded aweful slow to be for a warship. Then again, my reliable SO, keeps tracking the chasers far ahead, and I constantly urge him to keep the wheel on the fat chunk coming, he refuses to comply. I order the crew to detain him, and I assume his position. With my limited sonar senses, I open my copilot notebook, start up hydrophone tracker, and sit around a real life hour, studying the target movements, matching the hydrophone receiver with the propellers no less.




With enough data, I find out that the target speed is 5kts, course 99, incoming starboard beam. One more puzzle to figure is the range.
So, I draw an intercept bearing on the map, and wait for him to get in it, so I ping and have his range, problem solved. NOOOOO..

Turns out that once he enters the bearing on my hydrophone, I couldnt just fire. He maybe well close enough, so I fail at first because of this. On trial 2, I use both optical and sonar, only that the stupid sonar wheel turns away from last tracked bearing, thereby wasting precious seconds on bringing it back to bearing, pinging, then fight my way with the mouse in pressing the send range to tdc.

Last trial was THE ****!!! I had everything worked out, but only forgot to enter ship ID, and it's mast height, as well as depth settings for torpedos. Also, on reviewing the shots, I find out that they cross the bow of the ship, even when I get tubes 1 and 4 to a salvo click Right and 3 and 4 to a click left.

Of course something is soo wrong. Is the sonar reliable as optics? or are the optics that bad? And whats the best range for conducting a sonar only attack? My separation from the merchant was 6500 meters

I even set the speed to 6 since he'll floor it on sight of first torpedo.

I need your analysis fellas.


Thanks

[commandosolo2009]

wow!! 47 views, and no replies?

I guess its iatrogenic then..

Originally Posted by commandosolo2009

wow!! 47 views, and no replies?

I guess its iatrogenic then..

Well considering that there is not a single reliable account of a successful sonar only attack in the entire Pacific war, why are you surprised that yours failed?

Solving the target motion analysis problem with whiz-wheels and manual plots alone can never be effective although repeated often enough it might yield a success or two.

Only in the artificial world of SubSim is the technique alive, in the event the USN held the sonar only approach as doctrine until just after actual war started and then dumped it almost immediately as it did not work.

What you're experiancing is just the game imitating real-life.

[commandosolo2009]

Well, for two things, the waters were calm, and second, I wasnt detected. But it would have been cool if the technique was implemented in the war. Subs wouldnt have had to worry about being spotted at all... Well, at least with electric eels.. Which had flaws... I guess nothing is perfect. However, and surprisingly, I did a reboot today, but this time, raced to the intercept point. The target became clearer, and I delivered 3 out of 4 eels, into after the command deck, stack, and aft deck, the missed eel just passed too close to the rudder.... I sunk the bastard..


Got a bronze for the fourth patrol... Not fancy though... I like the medal system.... Hopefully by the end of it, I get the purple heart or the medal of honor

[Fish40]

I tried a sonar attack only once, and by chance it was a success. I came across a 3 merchant convoy in horrible weather. Visibility was about 700yds. I knew there would'nt be enough time to properly ID the target, and get a range useing the Stadimeter, so I decided to use a DO style attack. Since I had radar, getting course and speed were easy useing the 3min rule. After outflanking the ships, I headed 90 degrees to their course, dove to PD, and slowly closed the range, always tracking on sonar. I could hear they were pretty close, but could not see them. The beauty of the DO method is that range is not really a factor. I couldn't ping for a range, because there was an escort in the area. When the target sound was loudest on the appropriate bearing, I fired the fish and crossed my fingers. Not long after came the sounds of impact! It was a very impressive kill if I do say so myself!

[commandosolo2009]

Thats another good thing about SO. You can literally shoot with zero visibility, still hightening your chances of actually getting a kill. I got my fattest merchant on this patrol, by the help of periscope actually. The one modification that helped accuracy, was that I raced at flank underwater, and still the PK was off, so once I became close to about 3000 meters, I raised scope, corrected range and sealed the SO. It was by visibility this time though.. But certainly, when I get the electric eels, I'll even engage topside without DEs being able to find me. A radar also improves ranging, since the mast, gives a near center lock on the target, as its the hoist thru which radar emits... to mid-end 1942...