Oi and Kitikami

[jwilkerson]

ORIGINAL: Marc

1. The Kitakami and Oi shouldn't have radar at the beginning of the war.
Only Kitakami received No.13 radar but as late as 1944/45 during conversion to a kaiten carrier.
Attached is a page from the book showing some details about the radar types stating that No.13 radar was developed in 1943/1944.

Marc - I've found conflicting data on the IJN radar - look at this site Click_here. Which to my surprise says Kitakami and Oi did have radar at start of war ... perhaps we will have to go to primary sources to resolve - and I can't read Japanese !!!

On a second note - I ran 20 tests as follows:

Created 2 IJN Surface Action Groups ( SAG ) consisting of 1 CL and 4 DD each ... the DD were identical Yagumos and CLs were Sendai in TF1 and Kitakami in TF2. For the USN I also created 2 TF each containing 1 CL ( Detroiot class ) and 4 DD ( King class ).

So I ran 10 pairs of tests. All airplanes on the map were turned off ... one set of 10 tests involved 1 IJN TF against 1 USN TF ... and so did the other set, only difference was one set had Kitakami one set had Sendai. Oh and I selected identically rated leaders for both TFs on each side.

The IJN did get 2 radar spots to open the actions ( out of the 10 tests using Kitakami ) ... but more common for both the Sendai and the Kitakami TFs were IJN lookout spots. The USN got both radar spots and lookouts spots with radar spots being more common. Once the USN got a radar spot and the IJN got a lookout spot but the USN were still surprised !

Results were mixed - and surprise did not also seem to mean that the surprising side got lopsided results in their favor - but when lopsided results did occur - surprise came first ... so surprise seemed to be a pre-requisite for a lopsided result but not a determining factor.

So I guess the T13 radar does do something in the game - it does allow - about 20% of the time - the TF containing it - to obtain a radar spot. Thats interesting because ALL the sources I've seen [ including Marc's above ] indicate that the T13 was an "air search" radar set.

Still hoping someone can tell us what the "penetration" value for radar sets ( in the game ) means.

[Tanaka]

Type 13

Became Operational
operationally March 1943, experimentally 1941

War Status
wide operational use in war

Installed
ground, surface ship and submarine portable

Purpose
anti-air

Wavelength
200 cm

Peak Output
10 kw

Transmitter
parallel two wire

Receiver
UN-954

Detector
n/a

Detected
aircraft, group at 100 km, single at 50 km

Weight
110 kg

Number Built
1000

Antennae
dipole array with mat type reflector, send and receive common use





Type 13 sets are known to have been installed on the following ships :

Major Ships:

1941
month unknown
Oi, Kitagami

1943
June
Katori, Kashima, Kashii


October
Yamato, Musashi

1944
May
Nachi, Ashigara, Haguro, Myoko


June
Atago, Takao, Maya


July
Junyo, Oyodo, Noshiro, Yahagi - 2 sets in Noshiro and Yahagi


August
Amagi, Unryu


October
Nagato, Katsuragi - 2 sets in the latter


November
Sakawa - 2 sets

1945
January
Kitagami receives 2nd set


The experimental installations on Oi and Kitagami were probably the first examples of Imperial Navy shipborne radar. They were also the only Japanese ships to begin the war with radar installed.

[jwilkerson]

I assume you're using the source ...

radar_link

by "Martin Favorite" ... I don't see "Martin" listing his sources ... so we can't be sure this is valid data. Other sources are in contradiction to this one source. Do you have OTHER sources - or do you know the PRIMARY source for the "early" radar in IJN ?

ALso see MARC's thread on radar - essentially focusing on this topic.

[mogami]

Hi, Has it been mentioned that Oi and Kitikami's last refit gave them DC? (18)

[rtrapasso]

ORIGINAL: jwilkerson

Well - I just ran some tests.

This is a standard test scenario I cooked up a while back to test carrier tactics ... it pits one KB near death star with 4 CV and 2 CVL in 1 task force ( 312 carrier planes ) versus 4 USN task forces containing 1 CV each [ note the USN task forces have the slowest one leading and the other three set to follow - so almost all the time, even when reacting, they wind up in the same hex - this seems to be the best way of getting the largest possible strikes for the USN in 1942 given the "CV Coordination Penalty" the USN suffer ]. The IJN TF has 25 ships, the USN TFs have 15 each. The USN has 294 carrier planes. The test is based off the Scenario 13 start and the hypothetical carrier battle happens about halfway between Kwajalein and Johnson Is. so that no bases have any effect.

So I ran 2 groups of tests ... 6 tests in each group ... first group the IJN TF had both Kitikami and Oi ... in the second group of tests, the IJN TF had neither of these ships. I was looking for any difference in CAP over the IJN TF.

The average CAP over the IJN TF with K&O was 37.0 the average CAP over the IJN TF without K&O was 39.3 ... so at least in this group of tests K&O presence did not improve the CAP over the IJN TF. The variation in results averages at 2.6 hence the difference in the results is "within the margin of error" so it is not significant that in this group of tests K&O not present seemed to have improved the CAP.

So, it looks like the type 13 radar on K&O doesn't help KB.

But does anyone know what the numbers on the radar devices mean ? There seem to be 3 that might be meaningful.

Range,
Effect,
Penetration

I'm guessing range is the range in kilometers and I'm guessing the effect is the percent chance of detecting something, as these numbers run from about 45 up to about 70 ... but I'm clueless as to what the "penetration" number would be ... some radars have a 500 here ( including the type 13 radar in question ) others have 0 ... at first I thought the ones with 500 here might be the air search radars, but alas there doesn't seem to be any coorelation between which radars have the 500 and which don't along air search versus surface search lines. So any insite on these parameters would be appreciated !

But as it stands now - I can't detect any effect of the Type 13 on K&O in carrier battles.

Well, after much searching with the clunky forum software, i finally found the relevant post (compliments of Feinder) under topic "Why is there no description of the types of radar in the game???" :
fb.asp?m=743388

Name........................................Range........................................Effect........................................Type(?)
Type 271 Radar............................28...........................................75.............................................S
Type 279 Radar..........................250...........................................70.............................................A
SC Radar.....................................24...........................................50.............................................S
SG Radar.....................................28...........................................75.............................................S
SJ Radar......................................25...........................................70.............................................S
CXAM Radar...............................150...........................................50.............................................A
SCR-270 Radar...........................250...........................................70.............................................A
CPS-1 Radar...............................400...........................................80.............................................A
Type 13 Radar............................100...........................................45.............................................A
Type 21 Radar..............................20...........................................55.............................................S
Type 22 Radar..............................34...........................................60.............................................S
Sound Detector (J)........................25...........................................10.............................................A
Sound Detector (A).......................25...........................................10.............................................A

Not sure of the types. There was a column (penetration) where each set was either 500 or 0. I know the sound detectors are Air only (and were 500), so I assumed that all other sets with 500 penetration were Air sets. Don't know if some are air only, or surface only, or combined tho.

Range seems evident, altho I'm not sure what it's affect on the game is, I suppose for scramblin LRCAP for adjacent hexes.

My -guess- is effectiveness it the percent chance of a successful interception.

-F-

EDIT: I have highlighted the relevant passage. From what i know about other radars, Feinder's conclusions about the types of radar (surface vs. air) seem correct.

[PeteG662]

Jwilkerson,

In a previous thread there was discussion about the little message that pops up on the battle screen for surface TFs. You may want to check out and see if the IJN TF with no radar has radar spotting as well. The initial discussion of the battle screen message said that there were "pat" messages put in there. You saw one anomaly with the US achieving a radar spot yet being surprised. There have been instances of IJN TFs with no radar having the radar spot message show in the battle screen.

I still haven't seen anything in the game where having radar on ships does anything for the subsequent battle.......anyone out there see something different?

[jwilkerson]

Ok that was my "fear" that PENETRATION parameter was "supposed" to mean air if equal to 500 and surface if equal to zero ... unfortunately when I looked last week at the database .. their seemed to be poor correlation between real AS and Surface radars and the 500 and 0 values ... Ill try to report out on this over the next week ( traveling right now ).

As to possibility of radar messages being spurious ... I wouldn't rule it out. But I did get 2 out of 10 radar spots from the K&O task force[radar equiped] and 0 out of 10 radar spots from the non-K&O task force [ non-radar equiped ] in the 20 tests I ran ... not definitive ... but certainly aligned with the idea that probability of getting radar spot message is higher with radar equiped task forces.

[rtrapasso]

Ok that was my "fear" that PENETRATION parameter was "supposed" to mean air if equal to 500 and surface if equal to zero ... unfortunately when I looked last week at the database .. their seemed to be poor correlation between real AS and Surface radars and the 500 and 0 values ... Ill try to report out on this over the next week ( traveling right now ).

I think Feinder's data above is from the database editor, and the correlations with real radar types look ok to me.