SUBSIM Radio Room Forums - Patroling submerged

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- - Patroling submerged (https://www.subsim.com/radioroom/showthread.php?t=170772)

Ahhh! I thought I was using the doobies under the chin...Thanks RR...SK

Quote:

Originally Posted by Ducimus (Post 1416316)

I dunno, being able to hear 30 KM away in a set of hydrophones specified with a max range of 9KM seems like a bug to me. *shrug*

Well passive sonar should be modeled on a "decibel" principle. Your minimum "signal to noise" level (to trigger a "contact situation") could then correspond to a swimmer at 400 m, a merchie at 9000 m or a convoy at 25000 m. So yes you can have a contact at great distances as long as the "nature"/type of the target justifies it... me thinks, anyway :06:.

Quote:

Originally Posted by Rockin Robbins (Post 1416402)

Technically you are correct. Visual range is about 11 km conservatively. Sonar range is a ridiculous 30 km. Provided you are anchored, your area searched is 9 times greater with sonar. But on patrol you are not anchored.

If submerged, you are traveling at 1 knot to save batteries. Let's pretend you can go three knots and still have batteries at the end of the day just to be generous. So in 12 hours you can go 36 miles, searching a path 36 miles wide (18 mile radius is 36 mile diameter). Let's again be generous and square off the corners of your search path, giving you even more unrealistic search area. But we're trying to show that even fudging the numbers in favor of sonar, sonar sucks. Sucks badly. So you have searched an area 36x36 miles or 1,296 square miles.

Now lets take this puppy up on the surface where she belongs. Now we only search a 10 mile radius, but our search path is 9 knots times 12 hours long, 102 miles. 102 times 20 equals 2,040 square miles.

The winner by a resoundingly ludicrous margin: the surfaced boat with the lesser search range. In real life they could actually search a wider radius with high periscope than they could with sonar, resulting in a 10/1 advantage for the surfaced boat. If you have radar that is about the ratio.

No matter how you cut it, Patrolling submerged is foolhardy. You're burning up all your fuel charging batteries. If you are lucky(?) enough to find a target you have depleted batteries and are in no shape to go into combat. Your boat is just a travesty of fatal errors stacked on top of each other.

The ostrich strategy is totally without merit in every respect as a default way of hunting. It is not safe, it does not find targets. Do the math any way you want. It is moral bankruptcy of the highest degree.

Heh, I said sometimes it works... specifically when I'm in my patrol area, atop a likely shipping lane, I'll spend an hour or two at periscope depth to see if I pick up anything on sonar. I was south of Truk in the Pike and got a 10000 ton tanker this way, so it's not completely morally bankrupt! (grin)

Even without radar, using late-war tactics in the early war shows how much more effective the US sub force tactics became as the war continued. There really wasn't any way for the captains to have figured out the tactics in advance; the US (along with the Japanese) always assumed subs would be scouts and adjuncts to fleet actions, and trained accordingly.

Does anyone have some actual data/info on the hydrophones performance on surface (at varius speeds) versus "listening" submerged (at varius depths). I always was under the impression that you must "dip" for proper hydrophone "work".........

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Quote:

Originally Posted by WarlordATF (Post 1416443)

I agree its a bad tactic, but if you roleplay then until at least mid 42 its the historical way to do it. Realism is a very subjective subject when dealing with any type of sim so its up to each player to decide how he/she commands the boat. Some say the game is most realistic when set to 100% realism, however i doubt any captain did all the crew members jobs like in the sim. There really is no right or wrong way to play the game, if your having fun then your doing it right IMO.

Also i don't doubt for a minute that some Captains continued to spend the day submerged long after the order was retracted and those men deserved to lose their command. It must have been hard on these men to spend years training one way only to find out it does not work well in wartime and having to unlearn all that. New blood was needed, however before the change these men were just doing it the way the Navy instructed them to do it and their lack of success should reflect more on the people making the rules than the Captains following them.

I roleplay as the Captain, meaning i give the orders and the outcome is based on how well my crew performs. I spend my days underwater until mid to late 42, I use Auto-Targeting, I hardly ever man the sonar station but i will look at the Radar once in awhile. I count on my crew to do there jobs and for me thats the way i enjoy the game the most. I never use time compression when leaving port until i am several miles away and when i return i raise my scope if i have a successful mission (Wish i had a Broom! LOL) and dock the boat before i end the mission. I am not above using the external cameras, but never during combat and i have map contacts on to simulate the crew updating my map. I do use Limited Fuel and batteries, Realistic Repair and Loading Times and the other realistic settings.

Some would say thats unrealistic, but for me it makes me feel like i am a Captain of a Fleetboat. I don't knock anyones playstyle, To each his own.

Well said, we play the same for most part.I do not use auto targeting though.

Quote:

Originally Posted by Diopos (Post 1416869)

There don't seem to be any publicly released figures on the Internet. The advantages of the supersonic hydrophones are higher signal to noise ratio and greater directional certainty.

The disadvantage is that supersonic sounds are refracted, reflected and absorbed much more easily than the lower frequency sounds of the acoustic hydrophone head. So although the precise direction the high freq sounds are coming from can be more precisely determined, they are much more prone to refraction and reflection on the way to your sub than lower frequency sounds. That precise directional determination may not be worth the paper it isn't written on. Range is much shorter with supersonic sound because it is absorbed much more readily.

In order to do a proper long range sonar sweep in real life, they submerged to periscope depth or below, depending on acoustic sonar for long range and supersonic sonar in conjunction with the supersonic to fully develop the characteristics of a closer target.

The game doesn't begin to render the sophisticated (sorry modern submariners! I understand it's not sophisticated by today's standards.) array of filters available to glean hidden information from sound signals that were incredibly more varied than the very few recordings we hear repeated exactly time after time in the game.

With sonar, there is very little similarity between the game and real life.

Thanks RR,
for a moment I thought Ubi got it right and I was wrong concerning the ART of listening (with and without quotes) :DL

.

UBI getting something right? :haha::har::rotfl2:

Look, you gotta realize that for Ubi to "get it right" they would have needed hundreds of recordings. They would have had to have been able to manipulate those hundreds of recordings so you could count propeller rotations, hear continuous and continuously varying background noise.

The would have to have had own ship noises dependent on engine speed, which engines are running, different depth, what activities are going on aboard and the damage state of the submarine.

The would have to have refraction, reflection and absorption of sound varying by frequency of sound, wave state, temperature gradient, thermal layers, underwater obstacles, plant life, etc.

They would have to reproduce all the filters and all he switches in the real sonar, and each of the adjustments would have to realistically change the sound you hear, multiplying the necessary number of sound samples by a factor of at least 10.

And when they were finished, all you would have is a sonar simulator. There would be no more bandwidth left for the rest of the submarine! Ubi did really well, given the state of the art with computers and software.

Short cut methods, simplified tables, randomization factors and plain old talent may produce an interesting game without the need of a Cray supercomputer. In our case something as per a "dampening" factor for surface hydrophone work could urge the player to "dip" for more "productive" hydrophone work. After all it is a game not the navy's secret nuclear sub training simulator........

.

Quote:

Originally Posted by Diopos (Post 1418507)

Amen brother!

And I for one, "play" the game for enjoyment. Not for the white knuckled realism that others enjoy. To me, it is an enjoyable way to spend a little down time. Not a nifty new way to sit in front of the monitor waiting for something to happen. If I spend more than an hour (real time) without "something happening" then I feel that I am just wasting my time!

Having said that...

I prefer the yo-yo method of patrolling while out in the vast expanses stalking shipping lanes- but when my patrol area allows for it, I am perfectly willing (eager) to approach a suitable (some water beneath me) near coast position by stealth at night and then dive at dawn to simply sit and "listen" throughout the day, hoping to nab a coastal freighter or two.

Hmmm Lt. Corrado :hmmm:...That sounds like a nifty plan. I'm gonna try that on my next patrol. How far offshore do you lay in wait? Do you hang around harbors? I was thinking about that...SK

Quote:

Originally Posted by JoeCorrado (Post 1418571)

But when my patrol area allows for it, I am perfectly willing (eager) to approach a suitable (some water beneath me) near coast position by stealth at night and then dive at dawn to simply sit and "listen" throughout the day, hoping to nab a coastal freighter or two.

Yeah, this is my favorite prowling method, too. Find a nice spot of deep water somewhere where there's GOING to be a ship, stay submerged when the sun's up, and then aggressively chase down anything I happen to hear.

'Crocodile method', versus the more free-roaming 'shark' method, I suppose. Both have their merits, and I'll happily use whichever I think is best for my situation. I tend to run in Southeast Asia a lot, though, and there's lots of good places to lie deep and listen for prey down there.

And cast my vote for 'more fun before radar' are well.

Steelkilt: Look for someplace near a nice choke point, where shipping lanes enter or leave narrow straights. A lot of really good spots aren't near ports, actually.

The Bungo Straits is ringing in my ears...SK

Choke points good!