Early war escorts have radar enabled!!

[jhelix70]

This finding stems from the threads I began in the main forum and one about enemy sensors here in the mod forum. Basically I and others have noticed that Japanese escorts were spotting you first, way before you spot them. This is easily observable in the photo recon quick mission. Two destroyers guarding the entrance to the bay come beelining toward you well before they should have spotted you. The low profile of your sub should result in you spotting them first, not the other way around.

One idea I had was that the escorts were actually using radar. This would be nonhistorical because I believe Japanese escorts didn't get radar until very late, say 1945. The photo recon mission takes place in 1943.

I tested things in the photo recon quick mission. I first decided to test the radar theory, to get that out of the way, by altering the sim.cfg file. To my horror, by changing the [radar] Enemy surface factor (defines how much surface area must be presented to the sensor in order for detection) from 5 to 50000, normal behavior was restored. Now I spot the destroyers first, and they are on their normal patrol routes.

One important thing we have to determine is if this mistake just affects the missions, or do all Japanese escorts have radar in the campaign? I'm not sure how to look for that, but its disasterous for realism if they do.

In any case, you can bork the enemy radar by dramatically increasing the Enemy surface factor in the sim.cfg file. The disadvantage is that later in the war some escorts maybe should have primitive radar. But certainly not in '42-'43. In fact, "American experts placed Japan "four or five years behind" the United States in the development of radar."

[tater]

I think the eqp on the ships (or the improvements over time) can be altered. Escorts should not get surface radar til '44.

[jmjohnson36]

I have not seen any thing for radar in the eqp. file but if it is...ITS AN EASY FIX...I mod ships all the time...got an idea what Im looking for ?

[tater]

Actually, it's in for each ship by date under their sns file (Sea/Shipname/Shipname.sns).

So you can set the dates the sensors appear, or you can set them to NULL.

What TYPE of escort did you think had radar? I've checked a few and they are 1944. The type 13 radar is air search (very common, over 1000 built), and the type 21 is surface search. All the type 21s in game seem to happen in November 1944. I think that most escorts probably shouldn't have it, even then. Course the type 22 was made in more numbers, so they probably use the 21 as a general surface search radar. Problem is that it was installed here and there, not all ships got it.

Eeew, look at this:

[Sensor 9]
NodeName=R01
LinkName=NULL
StartDate=19380101
EndDate=19421001

[Sensor 10]
NodeName=R01
LinkName=Type13
StartDate=19421001
EndDate=19441101

[Sensor 11]
NodeName=R01
LinkName=Type21
StartDate=19441101
EndDate=19451201


R01 is the spot for "radar." Sop far so good. The start and end dates are the same, so the ship has no radar til october 1942, then it gets type 13, then it gets type 21. Here is the possible problem. The type 13 is ONLY air search. The type 21 does both. So we need to look at the stuff for the 2 types, if they allow the type 13 to do surface stuff, that needs to change.

Note that a very common (in GAME) escort is the Akizuki, the one DD least likely to escort anything but warships in RL. It has radar in 1942, 1 year before any ships had radar in the IJN. So does Asashio. Checking others. All those type 13 radars need the earliest date to be March 1943, though it would have gone to BBs, then CA, and then lesser types. Late 43 would make more sense, or at least late in the summer.

[jhelix70]

Escorts should not get surface radar til '44.
Agreed. I think summer '44 is probably about right.

Thanks for doing some digging Tater. I just know at the very least the destroyers in the 1943 photo recon mission have it. I think they were Akazuki class. Maybe we just need to adjust a few dates.

There is also the possibility of air radar showing ship contacts, since in the game the US radar is screwy too.

[tater]

OK, looked at the tweaker stuff. What does "MinSurface =" mean in there? it is set to 1.5 for both the type 13 AND the type 21.

[jhelix70]

good question, I'll have a look at the "fixing the radar" thread and see if they explain it.

Since air radar on enemy escorts hardly effects gameplay it might be safest to disable it entirely.

[LukeFF]

According to http://www.combinedfleet.com/radar.htm :

Type 21:
Type 21 first fitted to BB Ise in April 1942, Taiyo, Chuyo and Unyo in January 1943, others prior to August 1943. At least 30-40 sets built and used operationally.

Type 22:
Type 22 fitted to Kazegumo and Makigumo in March 1942, Hamakaze in June 1942, Akigumo and Yugumo in July 1942, Kongo, Haruna and Hyuga in October 1942, Katori, Kashima and Kashii in June 43,Yamato and Musashi in October 1943, other destroyers prior to September 1944. In wide use by mid-to late 1944. Type 22 radard while not designed for gunnery control provided moderately accurate data for this purpose.

[tater]

30-40 sets, and 100+ DDs not counting the big ships. So a few classes of DDs should get that (the type 22 is in game, BTW) I guess. The dates are useful though. The problem of course is that all ships of a class are identical, so one Asashio gets radar, and they all do.

With all the problems getting air radar not to pick up ships for subs, the same is likely true of the AI. The short term solution would be to dump the type 13, and have the first radar be the 21/22 later in the war. It's not like the AI battles are realistic anyway, letting them detect incoming planes is pretty meaningless. All that matters is how they interact with player subs.

[Mraah]

OK, looked at the tweaker stuff. What does "MinSurface =" mean in there? it is set to 1.5 for both the type 13 AND the type 21.

What's the name of the file you're tweaking? I can't locate the names.

thanks

[Mraah]

According to http://www.combinedfleet.com/radar.htm :

Type 21:
Type 21 first fitted to BB Ise in April 1942, Taiyo, Chuyo and Unyo in January 1943, others prior to August 1943. At least 30-40 sets built and used operationally.

Type 22:
Type 22 fitted to Kazegumo and Makigumo in March 1942, Hamakaze in June 1942, Akigumo and Yugumo in July 1942, Kongo, Haruna and Hyuga in October 1942, Katori, Kashima and Kashii in June 43,Yamato and Musashi in October 1943, other destroyers prior to September 1944. In wide use by mid-to late 1944. Type 22 radard while not designed for gunnery control provided moderately accurate data for this purpose.



Excellent link :up: :up: :up:

thanks

[tater]

Kazegumo and Makigumo, Yagumo, Akigumo were Yagumo Class DDs (visually identical to Asashio), Hamakaze was a Kagero (also looks like Asashio). Kashii, Kashima and Katori were Katori Class CLs.

[tater]

It's the AI sensors file in library I think. Using the minitweaker program.

[jhelix70]

With all the problems getting air radar not to pick up ships for subs, the same is likely true of the AI.
I just confirmed this in the 1943 photo recon mission. Tested changing the dates on Akazuki destroyers for types 13 and 21 radar, and nulling them out entirely. Nulling the 21 radar had no effect, but nulling the type 13 radar solved the unrealistic detection problem.

SO AIR SEARCH RADAR ON JAPANESE SHIPS IS DETECTING SURFACE TARGETS (IE. OUR SUB). Same bug as the radar on US subs. The problem is the air search radar is available much earlier than the type 21, so all enemy ships currently have an unrealistic detection capacity in the early and mid war eras.

I agree with Tater, we should "NULL" entry on the air search (type 13) radar for all ships while we figure out the radar error. This is done individually for each ship (Sea/Shipname/Shipname.sns)

[tater]

Did the type 21 detect you?

tater

[Ducimus]

OK, looked at the tweaker stuff. What does "MinSurface =" mean in there? it is set to 1.5 for both the type 13 AND the type 21.

How high the radar beam sits off the surface of the water. (also adjustable by MinHeight if i remember correctly)

In SH3 we had a broad range of radar, all the way down to 3 cm radar. So the min surface would be 0.03. That radar i hated with a fervant passion. 1.5 meters means it wont detect your periscoope unless its out of the water more then 1.5 meters.

[tater]

I was looking at ai_sensors.dat in the library I guess. There seems to be no difference between the 13 and 21 except the range. The other sensors other than radar do not use the MinSurface= parameter, and all the radar have it set to 1.5. I wonder what setting it to zero would do to the type 13...

Ah, so shouldn't the air search AI radar have this set to the height of a SHIP or greater? like maybe 20, 30, 40m?

[tater]

Sounds like the fix for the air search type 13 might be to set MinSurface= to a lareg number, like 100.

I wish I could just tweak and test, but it takes a year to load up on my machine, and anything screwy will CTD me.

[jhelix70]

Did the type 21 detect you?

tater

Confirmed, it appears to be working properly.

[jhelix70]

Sounds like the fix for the air search type 13 might be to set MinSurface= to a lareg number, like 100.


If MinSurface refers to the surface area of the target, then yes, putting a very large number there should disable all type 13's. I'll check and report later tonight.

[tater]

type 13:
Max range 10000
Max height 25000

Should be a group of aircraft at 100km, a single plane at 50km. The game values might all be shortened from reality however.

type 21:
Max range 14000
Max height 25000
RL could detect a large ship at 20km, single plane at 70km.

type 22:
Max range 18000
Max height 25000
Large ship at 34km, single plane at 17km

The difference in cross section between a large ship (presumably a cruiser or bigger? Maybe 5000+ tons?) and a sub, even surfaced is pretty huge.

The 13 and 21 are 200 and 150cm sets. The 22 is 10cm. I think I'd change the 13 and 21 to not ever detect a periscope, and they should probably have trouble getting a sail from bow or stern.

[tater]

Sounds like the fix for the air search type 13 might be to set MinSurface= to a lareg number, like 100.

If MinSurface refers to the surface area of the target, then yes, putting a very large number there should disable all type 13's. I'll check and report later tonight.

Mine was a reply to ducimus saying it was the minimum altitude the detector could see. So a large number so that even a surfaced sub would be invisible.

[akdavis]

I strongly recommend reviewing this thread before you get too deeply submerged in the radar issue:

http://www.subsim.com/radioroom/showthread.php?t=111562

[tater]

I did read that. The SD working as surface search makes player subs too powerful, while the jap escorts all having surface search radar makes THEM too capable. The tweak files for AI raqdar are not as complicated in terms of values, i think.

[Mraah]

It's the AI sensors file in library I think. Using the minitweaker program.

Much thanks again. :up:
Building tweakfile now ... argh, there are 61 sensors in this one.

[tater]

The tweak file was done already by nvdrifter, I'm using minitweeker to read it.

http://www.subsim.com/radioroom/showthread.php?t=109854

-AI Sensors.dat Tweak file:
Allows modding of AI sensors using TT SH3 Mini Tweaker program

[ref]

MinSurface is the minimum surface the sensor can pick (in square meters) at maximum range.

Ref

[jhelix70]

A quick question, I'm using the minitweaker for the first time. When you make changes to a number, at what point does it actually change the file? Does it overwrite it in the SH4 folder (thats where i pointed the program to). My changes to the type13 radar in the ai_sensors file don't seem to have any effect.

[Ducimus]

Ii'll double check when i get home from work. As i recall theres acutally two surface values where AI radar is concerned. One deals with an objects surface, the other deals with height from the surface of the water. I could be mistyping the name though, (im going by memory here, i dont have the files in front of me)

[Ducimus]

M'kay, reread some of this thread.

When someone said, "air search" radar, the first thing that popped in my mind was radar similar to Mark series thats assigned to aircraft. That was my misunderstanding. That radar is a bit different then the acutal problem. Air search radar in similar context to the SD radar problem?

Honestly, i would either: assign the destroyer another radar via the SNS file, reconfigure that radars geometry to act as an early version of surface searching radar, or remove it from 43 altogether. Seriously how often do you think JP destroyers need to be aware of US aircraft? Theres really not much of a need, so it's not really crucial that it detects only air units.

[tater]

Ah, so there is no limit on the altitude for AI radar then. Yeah, ducimus, that was my suggestion earlier. the AI vs AI combat is pretty crappy as it is, the best solution would be to just NULL the Type 13 radar out.

tater

[tater]

BTW, regarding the visual "sensor" does that work within the parameters deterministically, or is there a random element? Ie: You COULD be detected at such and such a range, but you might not, vs get inside X range going Y speed in Z seas, and you are detected 100% of the time.

I ask because while AI with radar when they shouldn't might be a problem, so is pulling up next to a DD and having them ignore you 100% of the time.

OTOH, I am with you on the "the heck with reality in the specifics, it's the outcome that matters" side of things. So while one such solution is to eliminate the air search radar, another similar technique might be to change the minimum surface area detected at max range to a LARGE number, like a huge warship cross section. I say this because the later radar models are identical in the tweak file except each has the max range increase by 4000m. So if the 13 detects you decks awash in the fog now at 7km, so will the 22, even if in RL it would see a DD at 7000m, but not a sub until 2000m (surfaced).

So tweaking that for a realistic outcome using the cross sectional area might make sense---all attention to its functionality for anythign other than detectign subs would be ignored, just try to get THAT part in the ballpark. If that makes any sense.

[Ducimus]

Visual detection:
varies on:
- enviormental variables (light, sea wave height, fog)
- How much surface area of your sub is being presented
- how fast your going.


Radar:
Id stick to a simplistic solution because its really not that improtant. At the most, id take the nonclamture an a 1944 surface radar, make the type 13 match it, and then shorten the range.

[ref]

A quick question, I'm using the minitweaker for the first time. When you make changes to a number, at what point does it actually change the file? Does it overwrite it in the SH4 folder (thats where i pointed the program to). My changes to the type13 radar in the ai_sensors file don't seem to have any effect.

Minitweaker creates a backup copy of the file you are editing "Copy of ...." , you must remove it from the directory for the changes to take effect.

Ref

[jhelix70]

Thanks for the help, ref.

Changing the max range value of type 13 radar to 1 (in the AI_Sensors file) solves the problem.

[Observer]

I have a solution for this that allows the radar to remain enabled and operational as intended, but I need to test a bit further first. I also have to create a special visual sensor to do the testing. If I get it working tonight, and can verify the results, I'll post the modified AI_Sensors.dat.