The Hunt for the IJN Cruiser Isuzu

Bubblehead1980 · 06-14-21, 02:17 AM

Sim played out close to what actually happened in April 1945.

TMO 2.5 with custom mods
100 realism. cams and contacts off.
USS Besugo SS-321
4th War Patrol

As mentioned, how this patrol has played out thus far in the sim resembles USS Besugo's actual fourth war patrol. Assigned to the Java Sea, she spotted the Isuzu and three escorts but was unable to close for an attack(where as I was able to attack, but missed) . A day later she was directed along with Charr and Gablian to intercept the cruiser, which had went to Bima Bay to pick up troops and then to Timor to deliver them. Returning to Bima Bay, she was attacked by Besugo in Sape Strait, but torpedoes missed and hit one of her escorts(I was unable to enter strait due to mines) , sinking it. The next day (April 7) Gablian damaged Isuzu and Charr scored hits, which caused her sinking. (Does not appear the AI subs I added damaged any of enemy this time, but they did attack and distract)

Having expended six torpedoes early in patrol and having damage, Besugo actually did return to Fremantle for repairs and to rearm, then returned to patrol. Later in April (April 23), she sunk German U boat U-183 in the Java Sea.

As part of my TMO upgrade, I added the Nagara Class to the roster and its historical movements for the mission using the Tabular Record of Movement from combinedfleet.com for Isuzu primarily as well as other sources. Also added the ULTRA messages. I added this sometime last year when working on traffic for the upgrade. The ULTRA reminded me of this. Was fun trying to chase down one specific ship, being thwarted by mines, planes, speed and course changes of target. Working with other subs (somewhat) and finally catching them. With the speed and course changes, could have easily not worked out. This is how I designed my upgrade, to bring variety and unknown factors, a challenge where success is not a guarantee. Really was fun to see it work out. Look forward to releasing soon., hope others enjoy it as well.

Will post screenshots in patrol log thread once patrol ends, don't want to have to tab out of SH 4 as will continue patrol tomorrow, causes issues when tab out, and time to go to bed lol.

3/24/1945-

0900-Departed Fremantle under new Commanding Officer LCDR H.E. Miller (editing the career track, switch up CO's every 5 patrols or so or to correspond with historical dates and focus more on the boat and crew than individual CO career, trying to implement this new focus into TMO update. LCDR H.E. Miller historically did relieve CDR T.L. Wogan after Besugo's third patrol in February 1945) assigned to patrol Area E6 in the Java Sea.

3/26- Fueled at Exmouth Gulf.

3/29-Transited Lombok Strait Northbound. No patrols encountered. Cleared strait by 2330 hours.

4/1-

0700- SD contact. Submerged to avoid.

4/2-4/3- patrol

4/4-

1640- SJ contact bearing 315 11 NM. 6 30 N 115 20 E. APR-1 detected emissions.

Target indentified as Nagara Class CL with two MS and one TB escort. Target on course 270 at estimated 22 knots.

1730- Submerged.

1740-Attack No.1 6 20 S 116 20 E. Fired four Mark 18 set for 10 feet from stern tubes.Range: 2100 yds. AOB 70 . Point of Aim: MOT with two degree spread using TDC spread knob.

1744- All torpedoes missed. Believe target changed speed as observed slight course change upon rising scope to observe expected torpedo impact. Sound showed torpedoes missing ahead by just 20-50 yards (estimated).

1745- Aircraft observed via attack periscope diving for Besugo. Ordered dive to 150 feet. Bombs detonated, no damage. One escort was heard breaking off to the area but did not search long, returned.

1820-Surface and initiated pursuit of enemy cruiser. Regained SJ contact but unable to close distance beyond 8 NM due to speed differential.

0000-Terminated pursuit. Returned to patrol area.

6 April-

0300- ULTRA received indicating enemy CL on transport mission from Kupang Harbor, Timor to Bima Bay Sumbawa Island would transit Sape Strait between 1600-2000 hours 6 April. . Along with Charr and Gablian, directed to area. (submerged AI torpedo firing subs placed in TMO upgrade).

Plot showed Besugo could make Sape Strait by 1300 on 6 April at 18 knots. Proceeding to Sape Strait.

1304- Enter Sape Strait(North). Observed multiple mines, Besugo had inadvertently entered a minefield. Backed out without course change and ordered guns manned. Using 40 MM, 20 MM, and 5 inch gun fire...fired upon and destroyed four mines.

1345- Departed area due to minefield. Moved to position 8 10 S 118 40 E off Sumbawa in attempt to ambush enemy upon arrival at entrance to Bima Bay.

1900- Enemy detected on SJ attempted to intercept, enemy speed was high with radical course changes close to shore after passing the narrow strait between Sumbawa and Sangeang Island. A persistent radar equipped patrol craft also contributed to interception.

2100- moved further away from coast

2300-ULTRA received indicating the CL (identified as Isuzu-Nagara Class) would depart Bima for Surabaya after 0200 7 April

7 April-

0651 - SJ contact bearing 031 11 NM. 7 50 S 118 30 E 35 NM NW of Bima Bay. APR-1 detected radar emissions. Went to GQ and initiated intercept.

0701- Radar indicated targets slowed with what was believed to be one escort and the Isuzu and another escort heading in different directions. Explosions of depth charges heard in distance. Another submarine attacked. Closed to assist but forced to dive by a patrol plane.

0811- SJ sweep detected two pips heading towards Besugo. Surfaced and closed. On calm, clear morning was soon able to spot the CL and MS in the distance. Plotted course and speed, believe would transit through the Tengah Islands. SJ showed another pip racing to catch up with two main pips, believed to be escort attempting to rejoin the Isuzu and the other escort.

0900- Ahead of target, waited for a expected zig to NW and submerged for attack.

0908- Target observed on course 310 at 19 knots. Target track was proving too close for bow shot and would be directly under the leading escort. . Besugo conducted a turn away to bring stern tubes to bear.

0912-Attack No 2: 7 18 S 117 55 E Fired 4 Mark 18 torpedoes set for 8 feet from stern tubes. Range 1900 yds. AOB 71 Point of AIM:Middle, Middle, Forward, Aft.

0914- Torpedoes 1 and 2 hit the stern and just forward of the stern of the cruiser, which set off the depth charge rack and aft magazine. Torpedo 3 hit amidships leaving a large visible hole under the middle stack. Torpedo 4 hit under the third stack. Target quickly slowed with a turn away from Besugo with two large fires burning. A list to starboard and by the stern quickly developed.

0915 a large series of explosions, presumed to be the magazines were observed. Isuzu quickly took a sharp down angle by stern while rolling to starboard and sunk at 7 18 S 117 E east. No survivors or lifeboats observed.

Simultaneously, pinging began. Observed a Shimimushu Class Type A Escort(previously indentified as an MS) closing in from 1800 yards. Ordered a dive to 450 feet, rigged for silent running, and depth charge. Two SBT decoys deployed. Escort did not take the bait and continued pinging Besugo.

0919. As Besugo passed 375 feet, escort passed overhead and dropped a sizeable DC pattern. All exploded above.

0921-Leveled off at 450 feet depth.

0922-0945- Escort conducted four attacks with the last two being accurate causing minor damage. Most serious was trim pump and battery damage.

0952- Besugo submerged at 600 ft depth. On the 5th attack, a close pattern exploded above the conning tower and forward torpedo room. Leaks and mild flooding occurred in both. The flooding in conning tower was quickly stopped but the flooding forward was more serious and quickly developed. With trimp pump not operating at 100 percent, the flooding forward gave Besugo a slight down angle and began to sink. To avoid rapid sinking, ordered rise on planes and minimum forward speed , adding back speed as required. Deployed three decoys as Besugo slowly descended . The 6th and 7th attacks landed no close charges as escort focused on escorts

1005- Besugo at 701 ft. Flooding stopped and rate of descent checked. Maneuvered about at 700-720 feet. Trim pump repaired.

1021-650 ft depth.

1031- Escort appeared to regain sonar contact as closed in and made another run. Two charges were fairly close and caused minor damage in engine rooms.

1035-1054- Escort, obviously first team, made two more attacks, shaking Besugo badly as she descended again to 675 feet but charges were above.Water finally pumped out of conning tower and forward torpedo room.

1101- Second escort arrived in area

1110-1304- Both escorts took turns making repeated depth charge attacks on Besugo. At 1231 a depth of 750 feet was reached to get under the intense and accurate attacks. Minor damage was incurred from these attacks, most serious of which being periscopes and JT listening gear heavily damaged.

From 1305, no sound contacts detected, believe escorts were "sleeping" listening for Besugo. To conserve power Besugo was back at 575 feet. slipping away to SW at 2 1/2 knots.

1619- Sound had one escort suddenly roaring to life at 900 yards and another at 1200, both began pinging and roared overhead. Dropping patterns of charges. However, none were close and appeared to explode either well above or well below Besugo. Sound then lost contact and was unable to regain. Believe escorts "sleeping"

1650- Sound reported two warships moving away at medium speed to NW. Secured from GQ maintained silent running.

1900- Periscope depth. Dark had fallen. Neither No 1 nor No 2 periscopes functional. Sound and SJ sweeps clear. Secure silent running.

1910-Surface.

2000-All damage repaired except No 1 and No 2 periscopes. Unable to repair attack scope while observation scope heavily damaged, barely functional. With eight torpedoes (All stern ) expended and scopes damaged, set course for Fremantle for repairs, refuel, and rearm with plans to continue war patrol afterwards.

06-14-21, 03:40 AM

Exciting! Highly because its more or less historical, that gives extra content.
Do you want to tell us your "custom MODS"?
What number will your next TMO get?

Bubblehead1980 · 06-14-21, 12:48 PM

Quote:

Originally Posted by easy

Exciting! Highly because its more or less historical, that gives extra content.
Do you want to tell us your "custom MODS"?
What number will your next TMO get?

Thanks, really was an exciting action and nice to stay busy in 1945 since targets are more difficult to find by this point. I agree about the historical part, which is why I completely revamped the task force layers in the campaign. Very few "random" warships generated and those that are are more in line with history far as composition route etc. Majority of warship encounters are now based upon historical movements, within parameters and limitations of sim of course. ULTRAS are provided when historically appropriate to provide player some alert. Player may happen to be at right place and right time to intercept. This cuts down on unrealistic warship encounters and means it you get a shot at a fleet carrier or a BB (once in a lifetime thing) then make sure do not mess it up lol. Also, provides that element of frustration and disappointment sub skippers and crews often encountered when they finally found choice targets and something went wrong...from torpedo malfunctions to target moving at high speed zigged at the last minute ruining the shot and sub in most cases would not be able to end around a BB/CA moving at high speed.

Also fun is receiving an ULTRA about an enemy submarines(as several did during war) and trying to locate it and get into position for attack, quite challenging usually, especially now that AI subs fire torpedoes.

My custom mods I refer to are primarily the campaign overhaul and ship packs for TMO, all part for my forthcoming upgrade for TMO 2.5. Many of my mods uploaded to subsim are including...torpedo update, depth charge mods, better hunters etc.

Name wise... I am undecided on name for my mod. I do not own TMO, Ducimus created it and he is no longer active in community so unable to reach him and thus would not call it TMO 2.6 or anything. Unless come up with some catchy name lol may keep it simple and call it Update for TMO 2.5 etc.

Mad Mardigan · 06-14-21, 01:09 PM

Quote:

Originally Posted by Bubblehead1980

Thanks, really was an exciting action and nice to stay busy in 1945 since targets are more difficult to find by this point. I agree about the historical part, which is why I completely revamped the task force layers in the campaign. Very few "random" warships generated and those that are are more in line with history far as composition route etc. Majority of warship encounters are now based upon historical movements, within parameters and limitations of sim of course. ULTRAS are provided when historically appropriate to provide player some alert. Player may happen to be at right place and right time to intercept. This cuts down on unrealistic warship encounters and means it you get a shot at a fleet carrier or a BB (once in a lifetime thing) then make sure do not mess it up lol. Also, provides that element of frustration and disappointment sub skippers and crews often encountered when they finally found choice targets and something went wrong...from torpedo malfunctions to target moving at high speed zigged at the last minute ruining the shot and sub in most cases would not be able to end around a BB/CA moving at high speed.

Also fun is receiving an ULTRA about an enemy submarines(as several did during war) and trying to locate it and get into position for attack, quite challenging usually, especially now that AI subs fire torpedoes.

My custom mods I refer to are primarily the campaign overhaul and ship packs for TMO, all part for my forthcoming upgrade for TMO 2.5. Many of my mods uploaded to subsim are including...torpedo update, depth charge mods, better hunters etc.

Name wise... I am undecided on name for my mod. I do not own TMO, Ducimus created it and he is no longer active in community so unable to reach him and thus would not call it TMO 2.6 or anything. Unless come up with some catchy name lol may keep it simple and call it Update for TMO 2.5 etc.

Ahoy, Bubblehead1980...

How about TMO 2.5: Bubblehead revamp/remix... just a thought... with a read me included that gives info on what's been reworked/revamped to have bettered it, with a nod to the original creator of it.

Just a thought...

M. M.

Bubblehead1980 · 06-14-21, 01:33 PM

Quote:

Originally Posted by Mad Mardigan

Ahoy, Bubblehead1980...

How about TMO 2.5: Bubblehead revamp/remix... just a thought... with a read me included that gives info on what's been reworked/revamped to have bettered it, with a nod to the original creator of it.

Just a thought...

M. M.

I may go with that. Of course will give a nod to Ducimus and a detailed readme about changes the mod makes to TMO etc.

I also plan to leave certain things out of the readme and include in a separate "spoiler" readme user can view at his or her discretion. I will do this since as a player, I like the unknown factor in the sim when on patrol, keeps things interesting in most cases. Run the sim enough can figure a lot of things out, like an experienced captain. Only downside of modding is learning the inner workings of things and can gauge how things will play out in many if not most instances.

06-14-21, 02:17 AM	#1
Bubblehead1980 Navy Seal Join Date: Apr 2009 Location: Florida USA Posts: 6,922 Downloads: 550 Uploads: 42	The Hunt for the IJN Cruiser Isuzu Sim played out close to what actually happened in April 1945. TMO 2.5 with custom mods 100 realism. cams and contacts off. USS Besugo SS-321 4th War Patrol As mentioned, how this patrol has played out thus far in the sim resembles USS Besugo's actual fourth war patrol. Assigned to the Java Sea, she spotted the Isuzu and three escorts but was unable to close for an attack(where as I was able to attack, but missed) . A day later she was directed along with Charr and Gablian to intercept the cruiser, which had went to Bima Bay to pick up troops and then to Timor to deliver them. Returning to Bima Bay, she was attacked by Besugo in Sape Strait, but torpedoes missed and hit one of her escorts(I was unable to enter strait due to mines) , sinking it. The next day (April 7) Gablian damaged Isuzu and Charr scored hits, which caused her sinking. (Does not appear the AI subs I added damaged any of enemy this time, but they did attack and distract) Having expended six torpedoes early in patrol and having damage, Besugo actually did return to Fremantle for repairs and to rearm, then returned to patrol. Later in April (April 23), she sunk German U boat U-183 in the Java Sea. As part of my TMO upgrade, I added the Nagara Class to the roster and its historical movements for the mission using the Tabular Record of Movement from combinedfleet.com for Isuzu primarily as well as other sources. Also added the ULTRA messages. I added this sometime last year when working on traffic for the upgrade. The ULTRA reminded me of this. Was fun trying to chase down one specific ship, being thwarted by mines, planes, speed and course changes of target. Working with other subs (somewhat) and finally catching them. With the speed and course changes, could have easily not worked out. This is how I designed my upgrade, to bring variety and unknown factors, a challenge where success is not a guarantee. Really was fun to see it work out. Look forward to releasing soon., hope others enjoy it as well. Will post screenshots in patrol log thread once patrol ends, don't want to have to tab out of SH 4 as will continue patrol tomorrow, causes issues when tab out, and time to go to bed lol. 3/24/1945- 0900-Departed Fremantle under new Commanding Officer LCDR H.E. Miller (editing the career track, switch up CO's every 5 patrols or so or to correspond with historical dates and focus more on the boat and crew than individual CO career, trying to implement this new focus into TMO update. LCDR H.E. Miller historically did relieve CDR T.L. Wogan after Besugo's third patrol in February 1945) assigned to patrol Area E6 in the Java Sea. 3/26- Fueled at Exmouth Gulf. 3/29-Transited Lombok Strait Northbound. No patrols encountered. Cleared strait by 2330 hours. 4/1- 0700- SD contact. Submerged to avoid. 4/2-4/3- patrol 4/4- 1640- SJ contact bearing 315 11 NM. 6 30 N 115 20 E. APR-1 detected emissions. Target indentified as Nagara Class CL with two MS and one TB escort. Target on course 270 at estimated 22 knots. 1730- Submerged. 1740-Attack No.1 6 20 S 116 20 E. Fired four Mark 18 set for 10 feet from stern tubes.Range: 2100 yds. AOB 70 . Point of Aim: MOT with two degree spread using TDC spread knob. 1744- All torpedoes missed. Believe target changed speed as observed slight course change upon rising scope to observe expected torpedo impact. Sound showed torpedoes missing ahead by just 20-50 yards (estimated). 1745- Aircraft observed via attack periscope diving for Besugo. Ordered dive to 150 feet. Bombs detonated, no damage. One escort was heard breaking off to the area but did not search long, returned. 1820-Surface and initiated pursuit of enemy cruiser. Regained SJ contact but unable to close distance beyond 8 NM due to speed differential. 0000-Terminated pursuit. Returned to patrol area. 6 April- 0300- ULTRA received indicating enemy CL on transport mission from Kupang Harbor, Timor to Bima Bay Sumbawa Island would transit Sape Strait between 1600-2000 hours 6 April. . Along with Charr and Gablian, directed to area. (submerged AI torpedo firing subs placed in TMO upgrade). Plot showed Besugo could make Sape Strait by 1300 on 6 April at 18 knots. Proceeding to Sape Strait. 1304- Enter Sape Strait(North). Observed multiple mines, Besugo had inadvertently entered a minefield. Backed out without course change and ordered guns manned. Using 40 MM, 20 MM, and 5 inch gun fire...fired upon and destroyed four mines. 1345- Departed area due to minefield. Moved to position 8 10 S 118 40 E off Sumbawa in attempt to ambush enemy upon arrival at entrance to Bima Bay. 1900- Enemy detected on SJ attempted to intercept, enemy speed was high with radical course changes close to shore after passing the narrow strait between Sumbawa and Sangeang Island. A persistent radar equipped patrol craft also contributed to interception. 2100- moved further away from coast 2300-ULTRA received indicating the CL (identified as Isuzu-Nagara Class) would depart Bima for Surabaya after 0200 7 April 7 April- 0651 - SJ contact bearing 031 11 NM. 7 50 S 118 30 E 35 NM NW of Bima Bay. APR-1 detected radar emissions. Went to GQ and initiated intercept. 0701- Radar indicated targets slowed with what was believed to be one escort and the Isuzu and another escort heading in different directions. Explosions of depth charges heard in distance. Another submarine attacked. Closed to assist but forced to dive by a patrol plane. 0811- SJ sweep detected two pips heading towards Besugo. Surfaced and closed. On calm, clear morning was soon able to spot the CL and MS in the distance. Plotted course and speed, believe would transit through the Tengah Islands. SJ showed another pip racing to catch up with two main pips, believed to be escort attempting to rejoin the Isuzu and the other escort. 0900- Ahead of target, waited for a expected zig to NW and submerged for attack. 0908- Target observed on course 310 at 19 knots. Target track was proving too close for bow shot and would be directly under the leading escort. . Besugo conducted a turn away to bring stern tubes to bear. 0912-Attack No 2: 7 18 S 117 55 E Fired 4 Mark 18 torpedoes set for 8 feet from stern tubes. Range 1900 yds. AOB 71 Point of AIM:Middle, Middle, Forward, Aft. 0914- Torpedoes 1 and 2 hit the stern and just forward of the stern of the cruiser, which set off the depth charge rack and aft magazine. Torpedo 3 hit amidships leaving a large visible hole under the middle stack. Torpedo 4 hit under the third stack. Target quickly slowed with a turn away from Besugo with two large fires burning. A list to starboard and by the stern quickly developed. 0915 a large series of explosions, presumed to be the magazines were observed. Isuzu quickly took a sharp down angle by stern while rolling to starboard and sunk at 7 18 S 117 E east. No survivors or lifeboats observed. Simultaneously, pinging began. Observed a Shimimushu Class Type A Escort(previously indentified as an MS) closing in from 1800 yards. Ordered a dive to 450 feet, rigged for silent running, and depth charge. Two SBT decoys deployed. Escort did not take the bait and continued pinging Besugo. 0919. As Besugo passed 375 feet, escort passed overhead and dropped a sizeable DC pattern. All exploded above. 0921-Leveled off at 450 feet depth. 0922-0945- Escort conducted four attacks with the last two being accurate causing minor damage. Most serious was trim pump and battery damage. 0952- Besugo submerged at 600 ft depth. On the 5th attack, a close pattern exploded above the conning tower and forward torpedo room. Leaks and mild flooding occurred in both. The flooding in conning tower was quickly stopped but the flooding forward was more serious and quickly developed. With trimp pump not operating at 100 percent, the flooding forward gave Besugo a slight down angle and began to sink. To avoid rapid sinking, ordered rise on planes and minimum forward speed , adding back speed as required. Deployed three decoys as Besugo slowly descended . The 6th and 7th attacks landed no close charges as escort focused on escorts 1005- Besugo at 701 ft. Flooding stopped and rate of descent checked. Maneuvered about at 700-720 feet. Trim pump repaired. 1021-650 ft depth. 1031- Escort appeared to regain sonar contact as closed in and made another run. Two charges were fairly close and caused minor damage in engine rooms. 1035-1054- Escort, obviously first team, made two more attacks, shaking Besugo badly as she descended again to 675 feet but charges were above.Water finally pumped out of conning tower and forward torpedo room. 1101- Second escort arrived in area 1110-1304- Both escorts took turns making repeated depth charge attacks on Besugo. At 1231 a depth of 750 feet was reached to get under the intense and accurate attacks. Minor damage was incurred from these attacks, most serious of which being periscopes and JT listening gear heavily damaged. From 1305, no sound contacts detected, believe escorts were "sleeping" listening for Besugo. To conserve power Besugo was back at 575 feet. slipping away to SW at 2 1/2 knots. 1619- Sound had one escort suddenly roaring to life at 900 yards and another at 1200, both began pinging and roared overhead. Dropping patterns of charges. However, none were close and appeared to explode either well above or well below Besugo. Sound then lost contact and was unable to regain. Believe escorts "sleeping" 1650- Sound reported two warships moving away at medium speed to NW. Secured from GQ maintained silent running. 1900- Periscope depth. Dark had fallen. Neither No 1 nor No 2 periscopes functional. Sound and SJ sweeps clear. Secure silent running. 1910-Surface. 2000-All damage repaired except No 1 and No 2 periscopes. Unable to repair attack scope while observation scope heavily damaged, barely functional. With eight torpedoes (All stern ) expended and scopes damaged, set course for Fremantle for repairs, refuel, and rearm with plans to continue war patrol afterwards. Last edited by Bubblehead1980; 06-14-21 at 06:10 AM.

06-14-21, 03:40 AM	#2
easy Stowaway Posts: n/a Downloads: Uploads:	Exciting! Highly because its more or less historical, that gives extra content. Do you want to tell us your "custom MODS"? What number will your next TMO get? Last edited by easy; 06-14-21 at 04:16 AM.