Busting Fortress Palembang - PTBS (J) vs Grollub (A)

[PT boat skipper]

19 August 1942

SITUATION REPORT


3. OPLAN
a) Lines of Operations and Decisive Points

The OPLAN, effective from 20 May, has three Lines of Operations and 13 DPs:



1) Cut SLOC to Australia: West and East
IOT delay enemy US naval offensive actions from Australia
KATSUIRO SAKUSEN

DP 1 = Conquer, or deny the use of Cocos island: RED
DP 2 = Conquer, or deny the use of Torres strait: RED
DP 3 = Conquer New Caledonia: RED
DP 9 = Defend Palmyra and Xmas islands: GREEN
DP 10 = INTACT KB with no limitations in fuel: RED



2) Conquer the border area India-Burma
IOT delay an offensive toward Burma and cut supply route to China
INMON SAKUSEN

DP 4 = Defend Rangoon: GREEN
DP 5 = Conquer Mytikynia: GREEN
DP 6 = Conquer Ledo: RED
DP 7 = DEFEAT enemy armies in eastern India: AMBER NOTE: changed from RED.
DP 8 = Conquer, or deny the use of Port Blair: AMBER NOTE: changed from RED.



3) Conquer China
IOT Win
SANGOKUICHI SAKUSEN

DP 11 = Conquer all oil-producing facilities: RED
DP 12 = Conquer route Hanoi - Hankow: RED
DP 13 = Conquer, or deny the use of all air bases: AMBER


Legend
RED = No or hardly any progress at all (0-19%)
AMBER = Notable progress (20-99%)
GREEN = Completed (100%)



NOTES:
DP 7 is AMBER due to progress of general offensive by 2nd Area Army.
DP 8 is AMBER due to landing operation on Ceylon.
DP 10 is still RED due to restriction of KB2 (Southern Army Reserve). This DP is expected to become AMBER at next monthly report due to KB2 being released from reserve task.
A recurrent staff conference will be held at GHQ on 20 August regarding the synchronisation of the three planned and on-going operations.

[PT boat skipper]

GHQ REPORT

19 August 1942



SOUTHERN EXPEDITIONARY ARMY (Burma-Java-Ambon)

Enemy sitrep:
ALERT! enemy made at major air attack against shipping unloading at Jaffna. CVE Taiyo and 6-8 empty transports were sunk. See air losses below.
ALERT! enemy moved back fighters to Silchar resulting in another air battle. See air losses below.
Enemy is moving ground reinforcements to Silchar from the NE and the SE. However, there are also indications that units are moving away from Silchar to Imphal.
20+ enemy submarines are active E Ceylon: S-41 was sunk SE Ceylon by I-9.
At Darwin, enemy fighter strength is estimated at 130+.

Current op:
GHQ staff conference is scheduled for 20 August.
INMON SAKUSEN:
2nd Area Army: Gen. Otozo Yamada is in tactical command of 16th, 17th and 25th Army. General attack is in progress. The fifth attack was launched against Silchar:

Ground combat at Silchar (59,39) - Japanese Deliberate attack
Attacking force 76707 troops, 1074 guns, 986 vehicles, Assault Value = 2290, adjusted assault: 1139
Defending force 35283 troops, 697 guns, 951 vehicles, Assault Value = 833, adjusted defense: 1847, terrain(+), leaders(+), experience(-)
Japanese engineers reduce fortifications to 0
Japanese assault odds: 1 to 2 (fort level 0)

Japanese ground losses:
5041 casualties reported
Squads: 93 destroyed, 284 disabled
Non Combat: 4 destroyed, 57 disabled
Engineers: 1 destroyed, 33 disabled
Vehicles lost 22 (3 destroyed, 19 disabled)

Enemy units:
16th British Brigade
14th British Brigade
254th Armoured Brigade
26th Indian/B Division
7th Armoured Brigade
27th Infantry Division
23rd British Brigade
26th Indian/A Division
26th Indian/C Division
216th Coast AA Regiment
2/9th Field Regiment
33rd Aviation Base Force
1st NW Frontier Base Force
25th Indian Mountain Gun Regiment
India Command
24th Indian Mountain Gun Regiment
2/11th Field Regiment
1st Bengal Base Force
77th Heavy AA Regiment
I Aus Corps Engr Bn /1

Enemy ground losses:
1489 casualties reported
Squads: 95 destroyed, 93 disabled
Non Combat: 3 destroyed, 55 disabled
Engineers: 0 destroyed, 7 disabled
Guns lost 86 (26 destroyed, 60 disabled)
Vehicles lost 24 (2 destroyed, 22 disabled)

16th Army: Three divisions (9th, 38th and 1st Tank) at Silchar. 19th Division is moving towards Silchar, ETA is 48H. 2nd Division is NE of Silchar.
25th Army: Four divisions (IGD, 5th, 56th and 18th) are at Silchar.
17th Army: 53rd Division is in hilly area WSW Tezpur. 52nd Division is SW Tezpur. 10th Division is NE of Silchar.
15th Army: defending Rangoon, Mytikynia and Lashio. Will advance to Imphal from the SW with the 33rd Division.
21st Division: at Imphal.
4th Division: 45 miles SW Imphal.

INMON SAKUSEN CE:
2nd Army: 24th and 25th Divisions are at Jaffna. 12th Division has been ordered by Southern Army to reinforce 2nd Army. The 12th Division will depart from Fusan to Singapore in 24h.
The assault against Jaffna will be made in 48H.
Combined Fleet:
KB1: supporting INMON SAKUSEN CE. Air battle over Jaffna - air losses:

Japanese aircraft
A6M2 Zero: 7 destroyed
A6M2-N Rufe: 4 destroyed

Enemy aircraft
Albacore I: 4 destroyed, 2 damaged
P-40E Warhawk: 10 destroyed
Kittyhawk IA: 2 destroyed
SBD-3 Dauntless: 2 destroyed, 2 damaged
Sea Hurricane Ib: 2 destroyed
P-39D Airacobra: 1 destroyed
Swordfish I: 2 destroyed, 1 damaged
Wellington Ic: 1 destroyed by flak

KB2: Note: Southern Exp. Army reserve force.
dai-2 Senkansentai (Kongo and Haruna) supporting INMON SAKUSEN CE.
dai-1 Senkansentai (Nagato & Mutsu) supporting INMON SAKUSEN CE.
2nd Fleet: dai-2 Suiraisentai: supporting INMON SAKUSEN CE.

3rd Air Army: at Rangoon.
21st Air Flotilla, 3rd & 5th Air Division: Silchar airfield was attacked.

Losses:
Japanese aircraft
Ki-43-Ic Oscar: 10 destroyed
Ki-21-IIa Sally: 1 destroyed, 4 damaged
Ki-45 KAIa Nick: 1 destroyed
Ki-48-IIa Lily: 4 destroyed, 2 damaged

Enemy aircraft
P-39D Airacobra: 1 destroyed
P-40E Warhawk: 2 destroyed
Kittyhawk I: 2 destroyed
F4F-4 Wildcat: 3 destroyed

Note: during next 24H the main effort will be offensive air operations.

Planned op:
INMON SAKUSEN PB Landing at Port Blair (16th Army).
SANGOKUICHI SAKUSEN: re-deployment to China (16th Army).



CHINA EXPEDITIONARY ARMY

Enemy sitrep:
70+ fighters at Chungking.
Enemy is reacting to 23rd Army's movements by moving reinforcements from Changsha to west of Henyang.
Enemy is moving about five units toward Mongol army.

Current op:
North China Army (1st, Mongol and 12th Armies): Mongol army is advancing west of Yenan. ETA is 2 days.
11th Army: in defensive position east of Changtei.
13th Army: in defensive positions SE Changsha, incl. three divisions in Changsha[/u].
23rd Army: is moving to position SW Hengyang.
25th Air Flotilla (Canton): again attacked and damaged the airfield at Hengyang.

Planned op:
SANGOKUICHI SAKUSEN: the total conquest of China.



4th FLEET (Central Pacific)

Enemy sitrep:
NIL.

Current op:
NIL.

Planned op:
KATSUIRO SAKUSEN: third phase: Torres Strait



SOUTHEAST AREA FLEET (New Guinea - South Pacific)

Enemy sitrep:
Enemy strongpoints are Port Moresby (70+ fighters) and Horn island (20+ fighters).

Current op:
Major submarine patrol area is Brisbane-Noumea.
Buildup of air (lvl 4) and naval bases at: Tulagi.
Buildup of air (lvl 4): Hansa Bay and Kavieng.

Planned op:
Buildup of air (lvl 4) and naval base at: Manus
KATSUIRO SAKUSEN: third phase: Torres Strait



5th FLEET (North Pacific)

Enemy sitrep:
ALERT! one enemy surface TG was discovered by aircraft east of Baker island.

Current op:
NIL.

Planned op:
NIL.



ASW and CONVOY COMMAND

Enemy sitrep:
Major concentration of enemy submarines near Ceylon.

Current ASW op and convoy movements:
GREEN: 1. Chittagong-Rangoon-Singapore: Losses: NIL.
AMBER: 2. Singapore to Japan: Losses: 1 AK (12 August), 1 TK (13 August).
AMBER: 3. Borneo to Truk: Losses: 1 AK (11 August).
GREEN: 4. Shanghai/Korea/Manchukuo to Japan: Losses: NIL
GREEN: 5. Karafuto-Hokkaido to Honshu (Japan): Losses: NIL

GREEN = no losses due to enemy action (last 10 days).
AMBER = minor losses due to enemy action (last 10 days).
RED = losses due to enemy action (last 10 days).

Planned ASW op:
Deploying ASW-air units to airfields North Borneo - Central Philippines.



ADDITIONAL NOTES
NIL.

[PT boat skipper]

GHQ REPORT

20 August 1942



SOUTHERN EXPEDITIONARY ARMY (Burma-Java-Ambon)

Enemy sitrep:
ALERT! enemy made an all-out air attack against remaining shipping unloading at Jaffna. 2 empty transports and 2 old DDs were sunk. See air losses below.
Enemy is moving ground reinforcements to Silchar from the NE and the SE. However, there are also indications that units are moving away from Silchar to Imphal.
Many enemy submarines are active E Ceylon.
At Darwin, enemy fighter strength is estimated at 130+.

Current op:
GHQ staff conference is scheduled for today. See separate post for minutes.
INMON SAKUSEN:
2nd Area Army: Gen. Otozo Yamada is in tactical command of 16th, 17th and 25th Army. General attack is in progress.
16th Army: Three divisions (9th, 38th and 1st Tank) at Silchar. 19th Division is moving towards Silchar, ETA is 24H. 2nd Division is NE of Silchar.
25th Army: Four divisions (IGD, 5th, 56th and 18th) are at Silchar.
17th Army: 53rd Division is in hilly area WSW Tezpur. 52nd Division is SW Tezpur. 10th Division is NE of Silchar.
15th Army: defending Rangoon, Mytikynia and Lashio. Will advance to Imphal from the SW with the 33rd Division.
21st Division: at Imphal.
4th Division: 45 miles SW Imphal.

INMON SAKUSEN CE:
2nd Army: 24th and 25th Divisions are at Jaffna. 12th Division is underway for Singapore.
The assault against Jaffna will be made in 24H.
Combined Fleet:
KB1: supporting INMON SAKUSEN CE. Air battle over Jaffna - air losses:

Japanese aircraft
A6M2 Zero: 11 destroyed (LRCAP)

Enemy aircraft
Fulmar II: 1 destroyed
Hurricane IIc Trop: 2 destroyed
Martlet II: 1 destroyed
P-40E Warhawk: 2 destroyed

KB2: Note: Southern Exp. Army reserve force.
dai-2 Senkansentai (Kongo and Haruna) supporting INMON SAKUSEN CE.
dai-1 Senkansentai (Nagato & Mutsu) supporting INMON SAKUSEN CE.
2nd Fleet: dai-2 Suiraisentai: supporting INMON SAKUSEN CE.

3rd Air Army: at Rangoon.
21st Air Flotilla, 3rd & 5th Air Division: Silchar airfield was attacked and damaged (no enemy fighters present).

Losses:
Japanese aircraft
NIL

Enemy aircraft
NIL

Note: during next 24H the main effort will be offensive air operations.

Planned op:
INMON SAKUSEN PB Landing at Port Blair (16th Army).
SANGOKUICHI SAKUSEN: re-deployment to China (16th Army).



CHINA EXPEDITIONARY ARMY

Enemy sitrep:
20+ fighters at Chungking.
Enemy is reacting to 23rd Army's movements by moving reinforcements from Changsha to west of Henyang.
Enemy is moving six units toward Mongol army.

Current op:
North China Army (1st, Mongol and 12th Armies): Mongol army is advancing west of Yenan. ETA is 24H.
11th Army: in defensive position east of Changtei.
13th Army: in defensive positions SE Changsha, incl. three divisions in Changsha[/u].
23rd Army: is moving to position SW Hengyang. ETA is 48H.
25th Air Flotilla (Canton): again attacked and damaged the airfield at Hengyang.

Planned op:
SANGOKUICHI SAKUSEN: the total conquest of China.



4th FLEET (Central Pacific)

Enemy sitrep:
CA/DD TF spotted SE Canton island. Note: most likely the same TF that was spotted east of Baker island yesterday.

Current op:
NIL.

Planned op:
KATSUIRO SAKUSEN: third phase: Torres Strait



SOUTHEAST AREA FLEET (New Guinea - South Pacific)

Enemy sitrep:
ALERT! I-17 reports many enemy ships including several BBs and APAs at Noumea. See separate flash report.
Enemy strongpoints are Port Moresby (70+ fighters) and Horn island (20+ fighters).

Current op:
Major submarine patrol area is Brisbane-Noumea.
Buildup of air (lvl 4) and naval bases at: Tulagi.
Buildup of air (lvl 4): Hansa Bay and Kavieng.

Planned op:
Buildup of air (lvl 4) and naval base at: Manus
KATSUIRO SAKUSEN: third phase: Torres Strait



5th FLEET (North Pacific)

Enemy sitrep:
NIL.

Current op:
NIL.

Planned op:
NIL.



ASW and CONVOY COMMAND

Enemy sitrep:
Major concentration of enemy submarines near Ceylon.

Current ASW op and convoy movements:
GREEN: 1. Chittagong-Rangoon-Singapore: Losses: NIL.
AMBER: 2. Singapore to Japan: Losses: 1 AK (12 August), 1 TK (13 August).
AMBER: 3. Borneo to Truk: Losses: 1 AK (11 August).
GREEN: 4. Shanghai/Korea/Manchukuo to Japan: Losses: NIL
GREEN: 5. Karafuto-Hokkaido to Honshu (Japan): Losses: NIL

GREEN = no losses due to enemy action (last 10 days).
AMBER = minor losses due to enemy action (last 10 days).
RED = losses due to enemy action (last 10 days).

Planned ASW op:
Deploying ASW-air units to airfields North Borneo - Central Philippines.



ADDITIONAL NOTES
NIL.

[PT boat skipper]

FLASH REPORT

DATE: 20 AUGUST 1942

FROM: I-17

TO: SOUTHEAST AREA FLEET

TEXT:
MANY ENEMY SHIPS INCLUDING BATTLESHIPS SIGHTED AT NOUMEA.

[PT boat skipper]

20 August 1942

GHQ STAFF CONFERENCE


1. INMON SAKUSEN

2nd Army’s landing at Ceylon has been costly. Losses so far are CVE Taiyo, 2 old destroyers and about 12 army transports. 2nd Army will launch a major attack IOT capture Jaffna tomorrow. If the attack fails, 2nd Army will await reinforcements (12th Division). However, the enemy is likely to reinforce Ceylon with at least one infantry division. Additional reinforcements are needed.

One successful effect of the Ceylon operation is that the enemy has diverted most of his aircraft assets from NE India to Ceylon. No enemy air-to-ground missions has been directed against 2nd AREA ARMY during the last days. Furthermore, remaining enemy fighter units have taken heavy losses defending Silchar airfield (level 2). Air superiority was today achieved over Silchar.

The Imperial War Council has stressed that it is of the utmost importance that INMON SAKUSEN is successfully concluded. The capture of Silchar-Imphal-Ledo will be a huge success since large number of the enemy’s ground forces will be destroyed. The capture of Ceylon will provide valuable flank protection and early warning if enemy aircraft carriers and/or invasion fleets approaches the area Chittagong-Rangoon-Singapore.

Imperial approval has been given for the transfer of 14th Army from KATSUIRO SAKUSEN to INMON SAKUSEN.

14th Army, GENLT Masao Watanabe
1st Division (reforming on Saipan)
14th Division (elite)
16th Division (-)
48th Division (-)
54th Division (new division undergoing basic training in Osaka area)
65th Brigade

SOUTHERN EXPEDITIONARY ARMY shall decide whether 14th Army is to initially join 2nd AREA ARMY in the attack against Silchar-Ledo, or to be initially used on Ceylon to bring that part of INMON SAKUSEN to a successful conclusion.


2. KATSUIRO SAKUSEN

KATSUIRO SAKUSEN III (Torres strait) is changed to KATSUIRO SAKUSEN IV (TO).
KATSUIRO SAKUSEN III (IN) is the shipping operation regarding the transfer of 14th Army from 4th FLEET to SOUTHERN EXPEDITIONARY ARMY. 14th Army units shall be replaced by garrison and defence units from 31st Army in the 4th FLEET area.
KB2 shall support KATSUIRO SAKUSEN III (IN).
KATSUIRO SAKUSEN III (IN) shall be initiated in 8 days.
KATSUIRO SAKUSEN IV (TO) shall initially be limited to the transfer of the 4th Air Division to Madang in eastern New Guinea.


3. SANGOKU SAKUSEN

This operation has been postponed IOT successfully conclude INMON SAKUSEN.
D-day is 25th December.


END