Static Search Vs. Dynamic Search

[TorpX]

Originally Posted by gi_dan2987

I totally see the point you are trying to make. I personally think that if the target is within feasible sailing distance, and you're not nearing the point of no return on your fuel level, then making a solid dash for attack position would be well worth the extra go juice.

I personally find that galavanting around at optimal cruise speed on the surface on a search course is the best way to increase odds at running into something. While surfaced and cruising around, you're covering way more square area in a shorter amount of time than putsing around submerged with the hydrophones. Granted your watch crew may have a detection radius much smaller than your hydrophones, but the larger area you can cover on the surface more than makes up for lack of spotting radius.

Perhaps this wasn't clear from my OP, but I consider there is a BIG difference between using fuel to pursue a known contact, and using fuel to cruise around aimlessly. I think most, if not all, skippers would have used almost any amount of fuel to attack a definate target. Also, I should clearify what I mean by a 'static search'. In my example, I allowed for 20 nm movement each night. ( O'Kane mentions this as a safeguard, in case they had been spotted by an aircraft and the enemy was routing ships around their position. Maybe I'm the only one who reads O'Kane. )



Anyway, to return to my example, searching at 5 knots only increases your chances by 14%. Searching at 10 kts. gives a 49% greater chance per day. This sounds good but.... this is at the cost of reducing your time on station by a substantial margin; hence your gains are illusory.

One thing I didn't include in the OP, because I hadn't thought of it at the time. The figures if calculated are based on a searching boat moving at a right angle to the shipping lane. If the searching boat is to stay inside the lane, it must periodically reverse course and backtrack. This would have the effect of reducing somewhat the 'search bonus'. (The boat would be searching water just recently travelled through.) How much, would depend on how often it would turn around.

While surfaced and cruising around, you're covering way more square area in a shorter amount of time than putsing around submerged with the hydrophones

It is not the square area, but the radius that is important. If you can see 5 nm and you detect X % of ships transiting the area, a 10 nm visibility will allow you to detect 2X %,(not 4X %). This may seem counter-intuitive, but if you diagram it, you will see it is true.



If you want a rule-of-thumb, I would say limit your fuel use in such a way that you would be able to complete your patrol schedule. That is, for a fleetboat, be able to remain at sea for at least 60 days. I'll admit, it is more "fun" to be cruising around "doing something" than sitting still, but this is not the same as saying it is a more successful tactic.

I was thinking it would be interesting to try to pin down the math more, so different search patterns could be analyzed according to the assumptions used, but as you are the only one to post a reply, I'm guessing there is limited interest in this topic. Anyway, thanks for the response.

[Armistead]

The formula probably has more bearing historically than it does in game. Course he may have readjusted fuel for 2.5, I'm still playing 2.2 where fuel really isn't an issue.

Even before that fuel has never been an issue, stay in shipping lanes and the traffic will come.

[magic452]

Just a few thoughts.

If I remember right you wouldn't get a mission to Luzon from Pearl via Midway. You would go to Japanese home waters that are closer so you have more fuel for patrolling. This would hold for both methods but with the static patrol the extra fuel would do you much good because you are already staying out 60 days.

I can only think of a single time I've spent anything near 1000 nm in pursuit and evasion. I chased a fast TF in heavy weather at flank speed for something like 200 nm. Even at that I RTB for torpedoes not fuel, I had one left. I was out of Brisbane so fuel wasn't a real factor.

Safety/weather allowance of 1000 nm. seems rather excessive.

So in my experience I have a lot more fuel than you are allocating for patrolling. I can't think of a single time I patrolled for only 8 days, it just hasn't happened.

31 ships in 31 days of paroling. Nice if you can sink 31 ships with only 24 torpedoes. In my experience two fish for every target and some times three.
dynamic search = 12.4, two torpedoes per ship = 24+ torpedoes.
A static search will net you 12 ships at best in 12 days or more patrolling and you RTB for lack of fish and fuel is no factor. I've gone many a day without seeing anything at 10 knots and that is covering 220 nm. more than a static search would and that's at 0.49% higher rate.

The idea is to sink enemy shipping not stay on patrol as long as possible.

The only time a static search would be of any real value is if you are assigned to patrol the entrance of a major port, a choke point or a mission to the Sea of Japan and even at that I think a dynamic search would be more productive. These areas are patrolled by aricraft and you can get down much faster at 10 knots than you can at zero. What O'Kane did or didn't do has little relevance to playing this game. Things just don't work like they did in real life.

Where do you get that PR figure? 1.0 verses 1.49 at 10 knots.

I don't patrol perpendicular to a shipping lane but rather zig zag along it's length.

#3 With a dynamic search you will leave that shipping desert just by the fact you are moving and patrolling the biggest possible area.
With a static search you leave that desert 20nm. a day or the the whole fuel thing falls apart. There are lots of shipping deserts out there and you go where you are sent. If you're playing by the book you do your patrol and call in for another mission, can get sent to many shipping deserts this way.

Anyway for my torpedoes I'll patrol at 10 knots and take my chances.

Magic

[Stealhead]

I fully agree with Magic your duty is destroy enemy shipping therefore one should use the tools at hand to maximum effect by staying in one spot your are adding the Japanese because now they just need to have the poor luck to come to you by being mobile they now must deal with the bad luck of being within 200 miles of you.I think like a tiger each tiger has a large bit of land that is his and he roams it constantly.

Considering that all of the most successful US Navy submarine captains all firmly believed in actively patrolling or "dynamically" searching it seems to me that it is the best method.Why sit in one spot and wait when you are very likely missing something 30 miles away that is not headed in your direction.I have never had fuel consumption issues myself with various versions of the game even if having to leave a dry area.I would say in most cases performing an active search in the typical "patrol this area for X hours" and covering a 100-120 miles radius I very rarely wind up not finding a ship or ships often I will find a convoy attack it and move on and wind up finding and hitting another convoy 40 or 50 miles and few hours searching later.Seems to me by sitting in one spot you are greatly lowering the odds of finding a ship unless you knew for certain that something was going to pass your position which in most SH4 missions you do not.I find a known lane and go hunting.If you ever read "Thunder Below" by Gene Fluckey you will be firmly convinced how much more effective it is to actively search but all the successful skipper where like minded they would have felt that being static and conserving fuel would be counter productive to searching the greatest area and therefore increasing your of finding ships which of course is the primary mission to seek out and destroy enemy shipping.

[TorpX]

Originally Posted by magic452

Just a few thoughts.

If I remember right you wouldn't get a mission to Luzon from Pearl via Midway. You would go to Japanese home waters that are closer so you have more fuel for patrolling. This would hold for both methods but with the static patrol the extra fuel would do you much good because you are already staying out 60 days.

The reason for conserving fuel is so you have it when you need it. If you get an ultra message or decide to move 300 nm to a different area, it is nice to have the fuel to do it.

I can only think of a single time I've spent anything near 1000 nm in pursuit and evasion. I chased a fast TF in heavy weather at flank speed for something like 200 nm. Even at that I RTB for torpedoes not fuel, I had one left. I was out of Brisbane so fuel wasn't a real factor.

The 1,000 nm is not to be taken at face value. 1,000 endurance at 10 kts is likely to be more like 250 at 20 kts. I tried to stick to the 10 kt endurance figures, since those are the figures quoted. If anyone knows the actual fuel consuption at 15 or 20 kts, please help me out.

Safety/weather allowance of 1000 nm. seems rather excessive.

See above.

So in my experience I have a lot more fuel than you are allocating for patrolling. I can't think of a single time I patrolled for only 8 days, it just hasn't happened.

First, I used a fairly distant patrol area for the example. Second, mod and game issues change what the in-game fuel consuption will be. I just used the quoted 11,000 nm @ 10 kts. figure.

31 ships in 31 days of paroling. Nice if you can sink 31 ships with only 24 torpedoes. In my experience two fish for every target and some times three.

Don't get hung up on the exact figures. These are relative numbers of contacts. In a low traffic area, the "31" contacts could be 3 or 4. The point is that if one method gives 30 relative contacts and the other gives 15, this says you can expect twice as many. The actual number would depend on the volume of shipping and your luck.

dynamic search = 12.4, two torpedoes per ship = 24+ torpedoes.
A static search will net you 12 ships at best in 12 days or more patrolling and you RTB for lack of fish and fuel is no factor. I've gone many a day without seeing anything at 10 knots and that is covering 220 nm. more than a static search would and that's at 0.49% higher rate.

As I said above, these are the relative probabilities of a contact, not the actual number of ships. This is impossible to calculate with very specific data for a particular area.

The idea is to sink enemy shipping not stay on patrol as long as possible.

A short patrol runs the risk of having few (or no) contacts. It's possible to run around like a speedboat and find a good number of contacts if there is a high volume of traffic to find. It's just as possible to burn up your fuel and be forced to RTB emptyhanded. There were war patrols where boats came back after 60 days with all their torpedos. Since you have no good way of knowing how many or when you will get contacts, it makes sense to plan for a long patrol from the start.

The only time a static search would be of any real value is if you are assigned to patrol the entrance of a major port, a choke point or a mission to the Sea of Japan and even at that I think a dynamic search would be more productive. These areas are patrolled by aricraft and you can get down much faster at 10 knots than you can at zero. What O'Kane did or didn't do has little relevance to playing this game. Things just don't work like they did in real life.

You may not like O'Kane. I started this thread for those who are interested in the RL techniques/math of patroling. I agree SH 4 is not too much like the actual war. IMO, it is rather too easy to come up with targets in the game. It depends a lot on your style of play.

Where do you get that PR figure? 1.0 verses 1.49 at 10 knots.

I gave the formula used in the OP. I have no easy way to post a diagram ATM.

I don't patrol perpendicular to a shipping lane but rather zig zag along it's length.

Going back and forth perpendicular to the shipping lane is the optimum method. This is easily visualized if you imagine going parallel to the shipping lane. You would not make contact with any ships that were not going make contact anyway. You would only hasten the contact from one direction or delay them from the opposite direction. Zigging has some advantage if you just "passing through" an area, but I don't see much advantage if you have reached the area you want to patrol.

#3 With a dynamic search you will leave that shipping desert just by the fact you are moving and patrolling the biggest possible area.
With a static search you leave that desert 20nm. a day or the the whole fuel thing falls apart. There are lots of shipping deserts out there and you go where you are sent. If you're playing by the book you do your patrol and call in for another mission, can get sent to many shipping deserts this way.

Again, you are not understanding the concepts here. I don't want to get into the whole mission/patrol area thing. I know some people ignore mission orders altogether, some are diligent in following them. I doubt many will spend a whole patrol in an unproductive area. If you use a static search technique, you can search an area for a week or two, and if you have not found anything you have plenty of fuel for a redeployment ( within reason). If you are using a dynamic search, and you spend a week or two and come up empty, you may not have enough fuel to do much about it.

Anyway for my torpedoes I'll patrol at 10 knots and take my chances.

Magic

Anyone is free to play as they please. I should like to reiterate this concept is not really mine originally. O'Kane mentions this in his book. I don't remember the exact words but the jist of it is that racing around did not provide much advantage in searching for contacts. He said this could be shown mathematically. I just did the math.

Many times new people have made posts asking why they can't find targets, or why they don't have enough fuel. Often, the response is to go here or there, because there is a lot of traffic over there in that time period, or a battle will happen on such and such date. RL captains did not have this advantage. They had to rely on sound technique and perserverence. I have attempted to show how they were able to do this.

[magic452]

I think we are talking about two different things here and I do see your point.

You're wanting to enhance the realism of the game with real world tactics.
This is fine

I'm trying to maximize what the game gives us to play with. I'm not a real stickler for realism I guess.

I don't have anything but respect for O'Kane but I play more like Morton.
I'm no WWII navel historian by any means but O'Kane and Morton and the like were no doubt given the best assignments. The 60 day no contact patrols were given to captains of lesser ability. You send your best to where the action is most likely to be. A 60 day no contact patrol may be realistic but not a whole heck of a lot of fun to play IMO.

The point I was so poorly trying to make is that, in the game, fuel is seldom a real concern so a dynamic patrol works well. So I'll take the higher rate of return and RTB as soon as possible and get back out as soon as possible. Torpedoes will be the determining factor not fuel.
Again in areas where a static patrol would work good are also where the flying thingies are and you can dive faster at 10 knots than zero.

I follow mission orders and call in and go the the next mission, don't freelance much. In game mission orders are far different than real ones but I'm not racing around with no plan, I use a tried and proven patrol method. The method depends on several factors, time, place, type of boat, etc.

I've tried perpendicular patrolling, not had much success with it but you make a good case so I'll give it another go in the right places.

As far as Ultra reports go I've only had two that were anyway near enough to take any action. The TF in my last post was one and the other was the Big Y near Truk. Long chases for both and still no fuel issues.

Your 10 knot speed is just fine with me as that is the most fuel efficient game wise and I never exceed that unless I'm in hot pursuit.

I was taking your figures to seriously and to be truthful I misread your formula as being absolute rather than relative. I'm not my sharpest at 1 AM, come to think of it, not all that sharp at 1 PM either.
Heck it's 1 AM again.
Good debate sir

Good luck and good hunting.

Magic

[gi_dan2987]

I would like to interject on all of these thought-provoking topics. First off, what is the name of this book by Mr. O'Kane?

Every skipper has different methods that could work given the circumstances. I believe that every situation is different and requires the ability to adapt. That being said, sometimes surface patrol courses are more effective than submerged static/dynamic sonar sweeps and vice-versa.

Captain Morton of the USS Wahoo took a sub that was once commanded by a cautious man who lacked proper incentive and aggression, and turned it into a tonnage logging, effective war machine. Mr. Morton spent a lot of time actively patrolling on the surface. Granted his crew paid the ultimate price for their bravery and aggression, but they also are listed in the records as one of the most successful submarines of the war.

[Stealhead]

O'Kane wrote two books one was about the Wahoo it is called "Wahoo: The Patrols of America's Most Famous World War II Submarine" O'Kane spent much time on this boat but obviously was not aboard when she was lost but he does his best to estimate her last patrol and hed have the best idea seeing as he was the XO for Morton.

The other book is called "Clear the Bridge" it is about the USS Tang which was O'Kanes boat she was lost to a circle runner but O'Kane a few others survived.Both books go into great detail the methods used by O'Kane and Morton while on patrol and they stayed in one place rarely.

"Thunder Below" is another excellent book written by a submarine commander Gene Fulckey who received a Medal of Honor for his exploits his book is very detailed as well.Fluckey who clearly from reading the book was a very good officer and cared greatly for his men and defends both O'Kane and Morton who had bad reputations with some war is war people die even when you make the correct choices and neither man made any obviously huge errors in judgment it was just a better day for the Japanese that day.

Personally I after reading these books largely used the same tactics and I had a lot of fun doing so therefore ever since then that is how I play.It seems to me that most of the successful boats generally searched actively most of the time but if the situation warranted they might stay immobile that can be very useful in some situations like if you are near a cost line and seeking a ship hugging the coast staying stationary is wise because you know generally where the vessel is going to be this tactic is also useful in several locations in Japanese home waters.

[TorpX]

Originally Posted by Armistead

The formula probably has more bearing historically than it does in game. Course he may have readjusted fuel for 2.5, I'm still playing 2.2 where fuel really isn't an issue.

Even before that fuel has never been an issue, stay in shipping lanes and the traffic will come.

I did intend this more for historical interest than as being essential for SH. People seem to either have a hard time understanding the math or just don't want to change their prefered game style. Oh well.

[Armistead]

Originally Posted by TorpX

I did intend this more for historical interest than as being essential for SH. People seem to either have a hard time understanding the math or just don't want to change their prefered game style. Oh well.

Yea, I get it, problem is odds math seldom worked in history or in real game, but interesting concept.

I sort of static and dynamic, depends where I'm hunting. If I'm in Formosa I know groups going north or south cant get past me, so I can sit there. The same with the shipping lane off the west coast of Borneo, you can sit 30 nms of Brunei and catch the large RSRD or TMO for that matter convoys coming either way. Simply, if you know the right places, you can sit and the traffic will come to you. That's the problem with predetermined traffic, easy to deal with once you know it.

Seldom did subs static search historically, they were basically always moving, moreso when they started acting like surface raiders. I think in Wahoo, the first patrol with an old Captain Wahoo spent over 500 dived, when Morton took over, it was 60 hours the first patrol......that's balls. He made subs moving surface raiders.