Patrol Report June 00 II
SS-184 Skipjack Ninth War Patrol covering the period from 5/4/43 to 5/28/43
To: ComSubPac, Commander SUBRON 4 - Manual TDC
PROLOGUE TO
Arrived Fremantle 3/27/43 after eighth war patrol.
NARRATIVE
Departed Fremantle 5/4/43 for Indochina. Thanks to information provided by CMDR Kulick elected to use manual-TDC for all torpedo's. This should limit our ability to send quick follow up shots as well as defend against escorts but we shall see.
Arrived on Station 5/13/43. Start patrolling outside Saigon for a few days.
Rmks 1. 23:00 5/13. SJ contact 14000. Looks like three or four targets bearing 300 into Saigon at 10-11 knots. Track and setup up TDC using radar information until first target is sighted at 23:31. Convoy is four ships in two columns. Initial attack will be on the lead ship in the near column a standard merchant of 9010 tons. 21:35 come to flank speed for the run in on surface from 6000 yards into firing position. Moon is up and behind us so will dive at 3500 yards for final approach and firing. Dive at 23:39 TDC and target tracking right in line with radar readings and TBT bearings. 23:43 fire two fish ten seconds apart speed high depth 5. First is a Dud second is a hit under his stack. 23:46 target has sped up and turns across our bow. Fire a third torpedo at 1000 yards aimed at MOT. This one hits target is burning. Fire fourth torpedo at 700 yards then dive to evade second ship in this column which attempts to ram. No sound of a hit or dud so we assume this torpedo missed, however diving at high speed cannot be sure. 23:53 back at periscope depth turn around and fire one torpedo from the stern tubes at the initial target range 1000 yards his speed is down to about 9 knots. This hits amidships and breaks him in two, target destroyed. The others are heading in three different directions.
Rmks 2. 00:13 5/14/43. The troop transport of 5440 tons has circled around and looks like he will cross our bow at about 1000 yards. Setup for a bow shot as he goes by. Fire two torpedo's one at the forward mast the second under the stack. First one hits under the mast and destroyed the target. Second one passed ahead of the ship nothing left to hit. Surface to search for survivors, none found. Clear the area to the NE at high speed.
Rmks 3. 0715 5/14/43. Sight two CL task force range 21000 yards bearing 030 in the Indochina shipping lane. Unable to close for an attack.
Rmks 4. 1230 5/14/43. Sight two more CL's using periscope at radar depth. No SJ contact but almost immediately an SD contact at 17000 yds. Two aircraft come right for us dive to 200 feet to evade. Both CL's turned away so suspect they either sighted our antenna and periscope or are able to pick up radar signals.
Rmks 5. 1830 5/14/43. SJ contact 14000 yards followed by an SD contact. Almost sun down so aircraft should depart soon. Track via SJ and turn to intercept. This is either another or the same CL group. Once the aircraft leave the area will attempt to gain firing position on the surface. 1837 aircraft are gone and convoy has zigged away. Surface come to flank speed heading down the base course to get ahead of the group. 1907 break off the pursuit cannot close on this group.
Rmks 6. 2100 5/14/43. SJ contact 13000 yards. Just finished recharging the batteries so come to intercept course and see what we have now. Two CA's an ISE class CV and 9 escorts. Fire three forward torpedo's at the CV range 1800 to 1500 yards then dive to evade. All must have missed but the 9 DD's sure know we're here. At 0015 on 5/15/43 all but three of the escorts leave. At 0100 surface and vacate the area. Minor hull damage in the pump and control rooms. Repaired, charge batteries resume patrolling.
Rmks 7. 0622 5/15/43. Sight two large fighting tops coming over the horizon. Lots of capital ship activity in this area All heading NE. This looks like a Yamato class and a Fuso class BB, one CA and six escorts. Fired four from the stern at the Yamato class range 2600 yards. One prematured, one dud and two hits. Dived to evade escorts. On one pass suffered damage to the DC motor 1 and Control room. Repaired them. On another pass suffered damage to steering gear, periscope, fwd battery and Control room again. All repaired except scopes are inoperative. 1130 finally get out from under the 8 or 9 DD's. Every fifteen minutes two or three more break off heading back toward Saigon. 1315 after one final wide circle the last three DD's depart.
Rmks 8. 1430 5/15/43. Surface to recharge batteries. At 1530 sight Sampans ahead turn to avoid contact. 1635 SD and SJ contacts. Dive to avoid due to no periscope. This group has four heavy screws and seven escorts. Will patrol along the coast at night looking for night surface action to use remaining torpedo's.
Rmks 9. 5/16/43. Positioned in a bay NE Saigon waiting for ships to cross our path. Dive at dawn to 200 feet wait out the day there and surface at dusk.
Rmks 10. 0120 5/17/43. SJ Contact 7500 yards intercept at high speed to investigate. 0130 sight two DD's and two Kuma class CLs radar indicates two more DD's dive to avoid. Moon is almost full and behind not a good set up.
Rmks 11. 2150 5/17/43. SJ contact 14000 yards attempt to intercept. We have a high speed group of two ships and two escorts heading away at 17 knots. Once we verify that two are escorts break off the chase to pursue something a little slower and less dangerous.
Rmks 12. 0410 5/18/43. SJ contact 14500 yards attempt to intercept again. This is a small freighter of 1330 tons at 14 knots heading WSW. The moon is behind him and setting so run in at flank speed for surface action. Fire one torpedo at 2000 yards 5 feet. Hit amidships and breaks him in two. Target destroyed close enough to shore so left survivors in their boats.
Rmks 13. 0400 5/19/43. SJ contact 13000 yards. Another high speed convoy 16 knots heading ESE. Escorts on both sides with the full moon decide not to pursue.
Rmks 14. 1940 5/19/43. SJ contact 14000 yards coming right at us. Turn stern to target and stop waiting for them to come into view. Looks like four ships in two columns from the radar. This group is at least six ships in four columns coming at us at about 9.5 knots. Turns out to be 4 columns of three ships. Fire two torpedo's at first ship in first column at 2500 yards and one at first ship in second column at 2200 yards. One premature and one hit on the ship in column one a dud on the ship in column two. Now see how they scatter and look for a final shot with the two remaining torpedo's forward. Fire two more torpedo's at the first ship in column one. One hit he is now burning one miss. Battle stations surface and finish off the cripple with 18 shells from the deck gun. An Oil Tanker split off from the group. Attacked deck gun 30 shells sunk the tanker. Radar detects another ship that has left the group. Pursue him and leave the group, to many armed merchant cruisers for deck gun action. Attacked a converted factory ship left him burning but still moving at six knots. Out of ammunition. While leaving he hit us with his deck gun causing unrepairable damage to DC motor 1.
5/28/43 arrived in Fremantle.
SUMMARY
Manual TDC versus Auto-TDC actually seems to have a higher hit ratio and much better than I expected. SJ radar gives excellent bearing and distance verification allowing the setup to be tracking very closely even before the target is sighted. Multiple targets can be quickly changed and fired upon assuming same base course and speed easily. Follow ups do require a step back to allow the targets to settle on a new course. Can't just send another torpedo at the target after a dud or a premature because TDC data is stale versus auto which automatically updates it. In general found manual TDC a little more work but a little better result.
Jap ASW
The groups we ran into were larger than in past patrols and much better organized. Escaping from a group of eight or nine DD's is difficult. They maintain the contact longer and do a better job of dropping the DC's. In two separate actions one a CV TF and the other a BB TF endured persistent and accurate attacks from the escorts. It definitely appears that the japs intend to protect their capital ships from submarine attacks. Also ran into a number of high speed and escorted convoys so they are also protecting their merchant fleet better.
Torpedo Performance Summary
Attack one - All fired at depth 5 feet high speed.
Hit Prem Dud Miss ����������������������� 3 0 1 1?
Result 9010 ton Standard merchant sunk
Attack two - All fired at depth 5 feet high speed.
Hit Prem Dud Miss ����������������������� 1 0 0 1 - nothing left to hit
Result Sunk 5440 ton troop ship.
Attack three - All fired at depth 5 feet high speed.
Hit Prem Dud Miss ����������������������� 0 0 0 3? Did not hear and could not confirm any hits.
Result nothing but a severe beating by the escorts.
Attack four - All fired at depth 5 feet high speed.
Hit Prem Dud Miss ����������������������� 2 1 1 0
Result 2 hits on Yamato class BB and a 6.5 hour very severe thrashing.
Attack five - Fired at depth 5 feet high speed.
Hit Prem Dud Miss ����������������������� 1 0 0 0
Result 1 hits on small freighter of 1330 tons target sunk.
Attack six - Two torpedo's depth 5 high speed, then two again followed by deck gun action.
Hit Prem Dud Miss ����������������������� 2 1 0 1 - aimed too far forward.
Result 1 hit and One premature, then one hit and one miss. Used deck gun to sink standard merchant of 7900 tons.
Attack seven - One torpedo depth 5 speed high.
Hit Prem Dud Miss ����������������������� 0 0 1 0
Result 1 dud no noticeable damage to transport.
Attack eight - 20 shells from deck gun.
Result sunk one oil tanker of 4670 tons.
Attack Nine - 45 shells from deck gun.
Result left one transport burning but still making six knots.
Totals
Hit Prem Dud Miss ����������������������� 9 2 3 6
Torpedo performance, hit and explode versus duds was slightly better then last patrol. The premature's were less and did not result in any misses. Ships were not alerted early enough to avoid the other torpedo's.
Deck Gun, expended all shells, 88 hits for 95 shots on three different ships.
SJ Radar
Performance varied but generally made contact at about 13000 to 14500 yards. One time contact was not until 7500 yards but we were in close to shore and that may have effected performance.
SD radar
Aircraft were detected at around 15000 yds during the patrol.
Damage
Hull damage moderate 32%, system damage light 8%, repair time nine days.
Weather Conditions
Fair and smooth seas while in PZ.
Ships sunk - five.
Standard Merchant 9010 tons Troop Transport 5440 tons Small Freighter 1330 tons Standard Merchant 7900 tons Oil Tanker 4670 tons ������������������������������ TOTAL 28350 tons
Respectfully,
LTCMD Ray McNeice
Commander SS-184 Skipjack