Search - random or set arcs?

[Ian R]

ORIGINAL: Kull

Draw your own conclusions:

ORIGINAL: Alfred

Although often asked, there is no particularly good consolidated thread which thoroughly deals with naval search/ASW arcs.  This thread is probably the best single thread.

http://www.matrixgames.com/forums/tm.asp?m=3299579&mpage=1&key=search%2Carc�

One of the problems you will encounter is that there are some very strong advocates for not setting search arcs but they tend to hide the details as to why they can get away with it.  Newbies read these no set arcs assertions and just adopt the principle that it works perfectly and obviates the case for setting arcs.  From that urban myths are created.  As always the devil is in the detail.  Particularly when reading my posts, one has to be alert to exactly what I say and the nuances I point out.

1.  Setting search arcs does increase micromanagement.  Players who are averse to micromanagement or at least want to minimise, tend to be very enthusiastic at the prospect of avoiding this additional work load.

2.  There is an automatic 360 degree search arc for up to 4 hexes on all naval search/ASW missions.  Set the mission out to 4 hexes, you get 360 degree coverage irrespective of what you do.  Set the mission out to 8 hexes, you get 360 coverage up to 4 hexes out.  Coverage for hexes 5-8 inclusive depends on what you do.  Set the mission out to 12 hexes, you get 360 coverage up to 4 hexes out, with coverage of hexes 5-12 inclusive dependent on your selection.

3.  Consider the range of your searching aircraft.  For example, Allied float planes are not really going to stretch the auto 360 degree coverage are they.  So there is no point in setting naval search arcs for them as the code has already taken care of that plus if you did specifically set such search arcs you would need to reset them every time a change of task force travel direction occurs as search arcs are not dynamic.

4.  Usually when the don't bother setting search arcs adherents assert that in their games they do very well without setting them they fail to point out that the DL and MDL of enemy task forces are also determined by other factors besides the efforts of their own planes flying search missions.  They also fail to point out that the sheer weight of embarked planes set to search usually is much greater than what they have on land and thus the malus associated with not setting arcs is mitigated.  As I said details, details which are very easy to overlook by newbies.

5.  Not all sea hexes are created equal.  There are frontal and backdoor approaches to most ports.  How often do you really think an enemy task force is going to, or is even capable, to come in from the back door.  Yet, because it is random, you will get backdoor searching if not set.


Experienced players who know exactly what they are doing and what the enemy capabilities are, can get away without setting search arcs.  They save themselves some micromanagement, but that is somewhat limited as setting of search arcs for land based aircraft is largely a one time set and forget task, only needed to be revisited when a major redrawing of the sea frontlines occurs.  It will superficially appear to be as effective as setting arcs, but it isn't.  So the real question for you is does the additional micromanagement represent an acceptable cost for the improved search footprint obtained when setting arcs.

Alfred

I rather thought Alfred was saying there, you should set search arcs for land based patrol squadrons, going beyond a 4 hex radius (set to 8 if ASW because that halves it), because that will possibly get you a better result, although the exe is not totally stupid and will direct some search capacity to the non obvious approaches to ports.

I.E. set search arcs for patrols out of the Conus, Australian ports, Colombo etc, as you retake major bases you may want to set some search arcs. These are long life asset direction "only needed to be revisited when a major redrawing of the sea frontlines occurs".

Don't set them for air combat TFs. Even if you might want that level of micro-management, you need 360 degree coverage.

Don't set them for short legged floatplanes on surface action TF's - it makes no difference out to 4 hexes.

There is a malus to not concentrating search assets to a limited area, i.e. the DLs you get will be better on the stuff in a concentrated area where you send the planes.

None of this sounds like rocket surgery to me.

[RangerJoe]

Long legged planes like Jakes probably could use search arcs, especially if changed based upon the direction of travel and/or the probably direction of the enemy. Of course, some should be left with no search arcs set.

[Kull]

I usually set ASW search arcs even though technically there's no benefit (the 4-hex rule). However, it can be VERY helpful, since toggling the arcs "on" tells me immediately which locations have active ASW search. It's certainly a heck of lot faster than checking each individual air field.

[OnWargaming]

ORIGINAL: Kull

I usually set ASW search arcs even though technically there's no benefit (the 4-hex rule). However, it can be VERY helpful, since toggling the arcs "on" tells me immediately which locations have active ASW search. It's certainly a heck of lot faster than checking each individual air field.

Sorry Kull, can you explain to me the 4-hex rule?

Thanks

[HansBolter]

ORIGINAL: OnWargaming

ORIGINAL: Kull

I usually set ASW search arcs even though technically there's no benefit (the 4-hex rule). However, it can be VERY helpful, since toggling the arcs "on" tells me immediately which locations have active ASW search. It's certainly a heck of lot faster than checking each individual air field.

Sorry Kull, can you explain to me the 4-hex rule?

Thanks

Search is 360 degrees out to a radius of 4 hexes even when you set limited search arcs.

Those arcs only apply beyond four hexes. Since all ASW missions occur at half the range setting on the aircraft only very long range aircraft will be able to take advantage of a limited arc setting for that mission and, at least in the early part of the war, long range aircraft that the Allies can afford to dedicate to the ASW mission are in short supply.

[OnWargaming]

Thanks HansBolter, another piece of the puzzle discovered [:D]

[RangerJoe]

Long Range ASW land based Allied aircraft early on are the Hudson/A-29s especially the LR version, the B17D which does not have the defensive firepower of the B17E but does have a nice long range. I had Devastators on ASW search bombing ships that they also discovered.

[OnWargaming]

So, I made a little test myself:

Guadalcanal scenario
- all aircrafts landed for both side except the Mavis air unit at Tulagi
- four Allied TFs in Remain on Station in the same sea hex for about 10 days
- a fifth Allied TF moved four days later in a sea hex within 4 hexes of Tulagi

Here the final position of the Allied TFs (all TFS were in the same hex for both tests)

[OnWargaming]

Mavis air unit on 50% Search with arcs set.

- 1st day nothing spotted
- In the next days two or three TFs have been spotted, never all four
- The fifth TF has not been never spotted even if inside the 4 hexes from Tulagi (I stationed it outside the search arc)

[OnWargaming]

Mavis air unit on 50% Search no arcs set (the distance has been lowered to 12 hexes, my mystake).

- 1st day one TF spotted
- In the next days two or three TFs have been spotted, never all four (more two TFs than three respect the previous test)
- The fifth TF has been spotted every time


According this small and SINGLE test:

- it SEEMS there is no difference for spotting with arcs set and no arcs behind the 4 hexes
- it SEEMS that if a TF is outside the arcs set cannot be spotted even if within 4 hexes (my test was at exactly four hexes)

[ITAKLinus]

I don't trust arcs and do just fine without them.

Time ago, I spent much time setting them properly and I have been dissatisfied with the results. Non-arcs are familiar to me and I somehow know what to expect from them.

Currently I use arcs just if there is a weird line of attack on enemy shipping where I want to avoid a CAP on some nearer base, which would drag my bobmers in NavB.

Also, I live under the convinction that often the arcs search in the nearby arc as well, but I use them so rarely that I really don't care.


For me, non-arcs is the way.

[Trugrit]

I use search arcs quite a bit but almost never just to cover a wide area of the open ocean.
I focus them and the trick to is to bring larger numbers into play when you use search arcs.

I use search arcs a lot for anti-submarine warfare.

So….Maybe I can add something for new players to think about.
Over the years I’ve found that some veteran players don’t post on the forum all the methods
They actually use in the game. They hold their cards close to their vest.

First...to protect my task forces against sub attack I’ll often form a protected Pipeline at critical ports
for my task forces to move in and out of.
(These are rear area important ports that are mostly free of enemy air attack)

In the diagram below I’ve set up a string of hexes that form a protected by air and sea pipeline.

A key is to have multiple ASW air groups and ASW task forces covering the line all the time.
For the air groups I can use bombers on ASW Patrol because they have a longer range.
I use multiple groups (many planes) to search a single sector.
(The B-17D is very good in this role)

Did I say I use many planes (multiple groups) in a single search arc? I think I did.

Using search arcs you want to bring larger numbers to a long range search like I described in this post:
fb.asp?m=4985693
In that thread Moltrey asked the question…...What do you do as Allies in the early war when you don’t
Have that many patrol planes? The answer is you can use bombers for naval search and ASW patrol.
Training Bomber pilots to search is very useful.

That way spotting an enemy sub task force in the pipeline is easier to do. I can attack or avoid the sub.
A spotted sub will seldom make an attack so spotting is as good as attacking.
(I use Destroyers for long range and/or Sub Chasers when they are close to port and can get a refuel stop)

My other task forces can enter and leave the pipeline at any point along it as necessary to avoid subs.

This way I can bring larger numbers into play and focus on one intense area instead of spreading
out my limited ASW resources.

Once set up I’ll watch it and use air and sea assets to clean it of any detected enemy subs.
(Using a method I’ll described next)

This is very effective if you are playing against the AI and maybe less so in PBEM games
Because your opponent has a brain and may detect it and take action.

If my opponent does not detect the pipeline I may tell him what it is and where it is in the hope
that he will move his sub task forces there. Then, I can more easily spot them, kill them, cripple them,
De-Fang and/or change my routes in and out of the port as required to avoid his sub task forces.

Note….If you can get the enemy to move his forces where you want them that is always a plus.
(It is not against the rules to talk to your opponent unless you have made it a rule)

Second….A first principle of intelligence gathering is “pattern analysis”.
Intelligence analysts attempt to discover patterns in enemy operations and exploit them.
This can turn bits of enemy information into “actionable” intelligence.
Actionable intelligence can be used to engage enemy forces.

In this game pattern analysis can be applied to anti-submarine operations.

In the game a submarine patrol task force is set up in one of two ways:

1. The task force has remain on station orders and stays in one hex only.
This is not usually used by experienced players because it is not as effective
as a patrol zone and players want to add the reaction setting which is more
effective with a patrol zone set. They are also easier to detect and attack
if they remain in one hex which is the main reason experienced players
don’t use remain on station or one hex patrol zones very often if at all.

2. Most common…...The task force has a patrol zone set. One, two or three hexes.
These can be linear or spread out to cover an area.

The important thing is that patrol zones create a pattern which can be exploited when detected.

In the diagram below, there is a detected submarine task force at Hex location A.
We don’t know how the task force has been set up or the location of any other Hexes
that make up the patrol zone but we do have one important piece of information:

We know the Hex it was detected in (Location A) and if it is running a patrol zone pattern
it will return at some point to that Hex. This is a fairly good indication of where it is going to
Be in a future turn. When a sub is detected I make a note of the Hex it was detected in.

That is actionable intelligence. When it returns to location A, I can be waiting there for it with
A dedicated ASW air patrol and multiple ASW surface task forces.

I use single destroyer ASW task forces. I like to use about 6 task forces with each TF set to a
Single hex patrol zone in the Hex the sub will return to. I use Destroyers for this because
Sub chasers don’t have the speed or the endurance I like for this type of work.

With this set up I have a good chance to get at least one and maybe multiple attacks on the sub
Every time it passes through that Hex depending on detection.

But another important thing is that the sub will get a chance to shoot at my destroyers.
The sub can’t usually pass up a chance to shoot at one of six surface task forces in the hex.
He has his choice since I’ve tried to make it easy for him.

I use destroyers because they are fast and it is very difficult for a submarine to hit one.
It does happen on occasion but chasing subs is one of their jobs and I want enemy subs to shoot at
My destroyers instead of my slow moving cargo and transport ships. That way the sub wastes it’s torpedoes
shooting at targets that are very hard to hit and returns to home port, if it is not dead, with the tubes empty.

Knowing where an enemy sub task force will be in some future turn is a good way to kill,
Damage or De-Fang subs.

In a PBEM game an opponent can always change the patrol pattern. That means he has to watch for detection
on his sub task forces and make the change. Not always a sure thing so I may still have an advantage.
It will add to his workload.

With all this said the next question to be asked is:
Since we know the Hex the sub is going to go to; can we lay a minefield to welcome it back?

The answer I would say to this is No. Minefields can be laid in the open ocean but they
deteriorate quickly and the chance that a lone sub will hit a mine in the open ocean is next to zero.
I’m not even sure it is possible since I’ve never seen it happen.
But...I’ve not seen a lot of deep ocean minefields.

Just something to think about.

[BBfanboy]

I say ixnay on the six X 1DD TFs in the same hex. Previous discussions made it clear that three DDs in the same TF is the ideal number for detecting and attacking the sub. This reflects RL, where a sub could elude a single escort fairly easily but could be boxed in after first contact by an escort group.

Also IME, too many TFs in the same hex make it harder to detect the sub. I don't know why this should be so - I don't think the game models noise saturation with the engines/sonars of many ships in the same area. But over many observations, if I had 2 ASW TFs in the hex, I had a good chance of finding and attacking the sub. If I had three or more TFs, very rarely did I get an attack. My guess is that the detection algorithm can't handle a large number of inputs.

[ITAKLinus]

I would also like to add that the more TFs you have in an area and the more likely it is that some important one doesn't get spotted by air search.

Basically, if you flood an area with TFs of various size, the air search will miss a very large number of them. At this regard, arcs can help.

I'm still convinced that arcs are to be discarded in favour of non-arcs.

Allied players might find it different since many of their sea routes are in open ocean, compared to the relatively coastal Japanese ones. As Japanese, I prioritize having my perimeter secured from random raids: ASW is done by the plethora of Jakes in NavS and Sallies/Ann in ASW. No need for arcs for either of those two.

[Trugrit]

ORIGINAL: BBfanboy

I say ixnay on the six X 1DD TFs in the same hex. Previous discussions made it clear that three DDs in the same TF is the ideal number for detecting and attacking the sub. This reflects RL, where a sub could elude a single escort fairly easily but could be boxed in after first contact by an escort group.

Also IME, too many TFs in the same hex make it harder to detect the sub. I don't know why this should be so - I don't think the game models noise saturation with the engines/sonars of many ships in the same area. But over many observations, if I had 2 ASW TFs in the hex, I had a good chance of finding and attacking the sub. If I had three or more TFs, very rarely did I get an attack. My guess is that the detection algorithm can't handle a large number of inputs.

Try this.

Open and start scenario 6 (December 8: The Full Campaign) in Head to Head Mode.

Stand down all your air groups so you won’t be bothered with air attacks in the replay.

As the Japanese player you know where the I-23 is located (Hex 183,106)

Advance to the Allied player orders and from up six ASW task forces and
set them all to a single hex patrol zone (Hex 183,106)

Stand down all your air groups and run the turn.

Because it is early war you are likely to lose some Destroyers depending on the commander
chosen for the I-23.

I was fortunate and got four attacks on the sub.
No hits because of the low skill of the Destroyers.