U.S.S. TRIGGER (SS-237) — war patrol report SS-237_TRIGGER_Part2.pdf

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3 October

0400 (L) Radar contact on ANATAHAN ISLAND, range approximately 100,000 yds.

0704 (L) Sighted ANATAHAN ISLAND bearing 200°T.

0712 (L) Sighted Liberator (PLANE CONTACT #1). (Numerous planes were sighted during remainder of run to SAIPAN but not listed as contacts).

0802 (L) Rendezvoused with escort and Blakely's Behemoths, and set course 160°T for SAIPAN.

1340 (L) Pilot came aboard.

1440 (L) Moored port side to U.S.S. SILVERSIDES in nest alongside U.S.S. FULTON.

1445 (L) U.S.S. SALMON moored alongside to starboard. Commenced voyage repairs and fueling. U.S.S. FULTON commenced work on forward TBT which was grounded, overloaded on DRA-11, and LC, motor generator voltage regulators.

4 October

1700 (I) U.S.S. SALMON and SILVERSIDES underway from alongside enroute patrol area. TRIGGER sailing delayed due to uncompleted job on forward TBT.

1800 (I) Lieut. John G. GLASSON, O-V(S), USNR., reported aboard for duty.

5 October

0554 (I) Underway in company with U.S.S. SEADAGON and escort AM102 enroute patrol area. Weather bad and getting worse.

1154 (I) Escort detached. Entered safety lane. Changed course to 310°T, making standard speed on 3 main engines.

6 October

0000 (I) Secured one main engine. Sea now force 6.

0502 (I) Secured one main engine. Sea now force 7.

1025 (I) Sighted Liberator close aboard (PLANE CONTACT #2). Dove.

1040 (I) Surfaced.

1055 (I) Changed course to 280°T because of seas, now force 9, and slowed to 1 main engine. Making 6 knots good and taking green water over the bridge.

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Enclosure (A)

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6 October (Cont'd.)
1315 (I) Seized fighting the war - commenced fighting the weather in earnest. Sea sickness affected 1/3 crew and officers.

7 October
0100 (I) Weather moderating slowly.
0542 (I) Put 2 main engines on propulsion.
0617 (I) Changed course to 290°T.
0900 (I) Sighted plane (PLANE CONTACT #5).
1350 (I) Sighted plane (PLANE CONTACT #4). Exchanged recognition signals.
1353 (I) Put 3 main engines on line.
1452 (I) Put 4 main engines on line. Sea now force 5.
2100 (I) Interference on S.J. Exchanged calls on S.J. radar with U.S.S. SEADRAGON, SNOCK.

8 October
0120 (I) Exchanged calls on S.J. radar with U.S.S. SEADRAGON.
0838 (I) Sighted plane (PLANE CONTACT #5). Dove.
0853 (I) Surfaed.
0859 (I) Plane (PLANE CONTACT #6) on S.D. Dove.
0952 (I) Surfaed.
1040 (I) Sighted plane (PLANE CONTACT #7). Dove.
1055 (I) Surfaed.
1405 (I) Sighted sampan (SHIP CONTACT #1) bearing 320°T. c/o 180°T to avoid as we were a day behind schedule.
1415 (I) Sighted single engine plane (PLANE CONTACT #8) on starboard quarter closing fast. Dove. Closed sampan. Decided sampan well off Fleet track and headed away. Too rough for 4"; vessel too shallow for torpedoes.
1545 (I) Changed course to 290°T.

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Enclosure (A)

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8 October (Cont'd.)
1842 (I) Interference on S.J. radar. Exchanged calls with U.S.S. FLYING FISH. Gave her dope on sampan.

9 October
1030 (I) Sighted 3 planes (PLANE CONTACT #9) circling with elevation angle of 65°. Dove.

1128 (I) Surfaced. We were still 10 hours behind schedule.

1400 (I) Entered patrol area 11C at Latitude 23-00 N, longitude 125-05 E.

10 October
0235 (I) Radar contact on FORMOSA, range 90,000 yards.

0522 (I) Sighted HOIKENKAN HAKUCHI (KARENKO) light, bearing 280°T.

0551 (I) Submerged with KARENKO bearing 270°T, distance 12 miles, and commenced approach to investigate harbor and adjacent coast. Despite delay of 1 day at SAIPAN, typhoon weather, planes, and sampan, had managed to arrive on station only 6 hours late.

1200 (I) Having closed harbor to 3 miles and found it empty, took pictures and o/c to 030°T to open coast.

1853 (I) Surfaced on course 030°T, 12 miles from beach. Cleared numerous fishing lines from bridge.

2145 (I) Picked up radar interference on APR on 151.megs.which got progressively stronger until at

2158 (I) The pip covered whole oscilloscope. At this instant, a pip (PLANE CONTACT #10) appeared on SJ at 6,000 yds., and again at 3,500 yds. Dove and o/c to 035°T.

2203 (I) Sound picked up fast light screws on bearing 005°T, target #1 (SHIP CONTACT #2) and bearing 110°T, target #2. Target #1 was drawing slowly to left. Nothing seen through periscope. Both were sampans.

2225 (I) Target #1 was lost at 335°T, having passed out of range.

2230 (I) Target #2 was heard until surfacing when it bore 035°T.

2235 (I) Went to radar depth and manned S.J. and A.P.R. Small radar pip bearing 128°T at 2800 yds. was verified by sound as heavy screws with turn count of 140. J.K. also reported this. This was not a good steady pip. Had the appearance of a periscope of wave pip. There were no other radar indications. Sound still had screws at 025°T.

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10 October (Cont'd.)

2250 (I) At battle stations submerged. Radar had had small pip intermittently on bearing 120-125°E since 2235. Sound had had continuous contact on bearings 120°-125°T and 0°-5°-030°T.

2257 (I) Surfaced - c/c to 000°T. Radar could not pick up pip at 120°T, but sound still had screws at 120°T and 022°T. All stopped.

2305 (I) c/c to 160°T, 1/3 speed, to open on screws at 022°T which were on steady bearing. Still nothing on radar.

2306 (I) Radar pip, small, at 120°T, range 2,300, verified by sound. At this time sound picked up 7 distant pings from this bearing on long scale.

2325 (I) Sound reported heavy screws bearing 130°T making 140 turns. All ahead standard on 3 K.E.'s on course 120°T to run over his pip.

2327 (I) S.o. radar interference bearing 080°T. Assumed this to be the SILVERSUIDES, and attempted to contary her but got no response. At this time sound lost contact on screws at 137°T.

2345 (I) c/c to 060°T to try to close SILVERSUIDES and find out what the score was.

2345 (I) Secured from battle stations. No screws, no pips, no interference. c/c to 005°T.

11 October

0005 (I) Fire in forward engine room. The field coils of #1 auxiliary generator caught fire and the generator was out of commission for the remainder of the patrol.

0130 (I) Changed course to patrol east and west along latitude 25 off SAMUCHO KAKU, having decided to pass up S00 WAN and get the lay of the land off the northern end of the island in view of coming operations.

0539 (I) Made quick dive with SAMUCHO KAKU bearing 270°T, distance 10 miles, and began closing to investigate. During the next hour, evidenced a 3-4 knot set from 090°T and at

0643 (I) with SAMUCHO KAKU light bearing 270°T, distance 8,000 yds., c/c to 000°T. Sighted beached wrecked freighter in core north of SAMUCHO KAKU. No activity whatsoever in the vicinity, and at

135 (I) c/c to 110°T and commenced opening range to seaward.

1837 (I) Surfaced on course 110°T. Patrolling area while proceeding northward to take position at dawn as life guard.

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Enclosure (A)

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12 October

0320 (I) Radar contact bearing 095°T, distance 8,500 yds. Manned radar and plotting party. Fips were very small and night was very dark. About 10 small pips (SHIF CONTACT #5) were seen and closed to 4,000 when they could still not be seen from the bridge, so evaded as we wanted to take no chance of disclosing our position at this time. Believed this to be a small fishing fleet. This "fleet" got in and out of our way all night while we were trying to get on station.

0630 (I) On station 35 miles, bearing 060°T from BITO KAKU. Sampan convoy just ahead and going toward KIRUM right on our life guard line. Decided to close and sink them with 4" gun.

0705 (I) Sighted large twin-engine double-tailed bomber (FLAME CONTACT #1) at range of 6 miles. Dove.

0710 (I) Sighted single engine fighter (FLAME CONTACT #12).

0814 (I) Surfaced - commenced closing reference point at 6/s on 1 M.E. No fighter protection. Between this time and 0913 when scouts arrived, 3 single dsp planes closed but headed away before we had to dive. Our formations in the distance seemed to deter them from attacking or perhaps they thought we were a straggler sampan. (Sampans were still in sight).

0902 (I) Sighted first of 4 waves of our planes to attack and planes were in sight for the remainder of the day. At this time our fighter escorts had not arrived and the situation on the bridge was still tense as we did not know friend from foe at this time. Planes sighted during remainder of strike are not listed as plane contacts.

0913 (I) Large column of smoke and high flame sighted just on horizon bearing 307°T about 10 miles north of end of FORMOSA. Commenced closing on 4 engines thinking it was downed plane. At this time, our escorts finally showed up and informed us it was a sampan damaged by our planes. Commenced patrolling station slowly under our fighter coverage. Tension on bridge had eased slightly. The island was now almost obscured by fog and mist and we could see nothing of the show.

1031 (I) . Skipped 5 F6F fighters headed for us, one plane trailing black smoke. Were notified by escorts he was going to land close aboard.

1100 (I) Plane made flat landing in water 300 yds. dead ahead, broke in two and apparently sank immediately. Pilot was then seen in water as we approached a "friendly" speed. Pilot was struggling weakly, apparently overcome by shock, gas and oil fumes, and salt water. Lieut.(jg) C. HOBERTS dove into the water and swam a line to him and assisted him alongside. Picked up Lieutenant (jg) JOHN J. McGUIRE, U.S.N.R.,

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12 October (Cont'd.)
1100 (I) Cont'd.
#250542, of Squadron VF8 from U.S.S. BUNKER HILL, suffering from shock, shaken up, and weak, but without a scratch upon him. Notified his cohorts over VHF of his condition.

1235 (I) Fighter escorts departed without reliefs due to gas shortage. Were forced down twice by friendly (f) planes coming in on us with no IFF before

1450 (I) when relief fighter escort showed up.

1500 (I) Received word that pilot was down at entrance of KIRUN Harbor with a Nellie circling him. There was no trace of him upon later investigation by plane.

1630 (I) Operations completed for the day. Escorts departed. Dove and c/o to 180°T for a few hours relaxation.

1915 (I) Surfaced - commenced patrolling area.

13 October
0600 (I) Dove in assigned life guard position, bearing 120°T, distance 30 miles from BITO KAKU.

0715 (I) Sighted 2 dep planes (PLANE CONTACT #13).

0737 (I) Surfaced and commenced patrolling in position awaiting fighter escorts. Same suspense until

1000 (I) when escorts arrived on scene.

1400 (I) Received message from escorts that plane was down 58 miles, bearing 252 from reference point. Sent TRIGGER serial one to CONSUBIFAC, info TANG of this fact. Weather very hazy over FORMOSA and few planes seen. Business was very slack all day except for several Jcp plane approaches to 8 miles and usual friendly plane approaches without IFF.

1600 (I) Escorts departed - submerged 10 miles east of SAMUCHO point on course 090°T.

1904 (I) Surfaced. Commenced patrolling station.

2000 (I) Made contact with SILVERSIDES - exchanged calls.

14 October
0605 (I) Made quick dive 20 miles east of BITO POINT awaiting developments.

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Enclosure (A)

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14 October (Cont'd.)
0605 (I) Cont'd.
If no air strikes developed intended to proceed along northeast coast of FORMOSA between BITO KAKU and KURUN KO.

0920 (I) Sighted 9 planes (PLANE CONTACT #14) circling over northern end of island. Could not identify them—no reversed course to 090°T and went 2/3 speed to open coast, and at

1200 (I) surfaced. No other planes were sighted during this time, and upon surfacing could not raise anyone on life guard frequency or V.H.F., so at

1303 (I) Submerged and continued submerged patrol off SAMUCHO POINT.

1900 (I) Surfaced.

2100 (I) Destroyer reported by B-29's heading up east coast of FORMOSA. Changed course to 285°T on 4 engines attempting to intercept off SAMUCHO POINT should he be heading for KURUN KO.

15 October
0330 (I) c/o to 060°T heading for YONAKUNI JIMA to fix position and switch areas with SILVERSDES.

0630 (I) Radar contact on YONAKUNI JIMA, range 50,000 yards.

0702 (I) Submerged - c/o to 025°T.

1445 (I) Sighted plane (PLANE CONTACT #15).

1658 (I) Sighted plane (PLANE CONTACT #16).

1858 (I) Surfaced on course 270°T - c/o to 100°T to close YONAKUNI JIMA.

1935 (I) Radar contact on YONAKUNI JIMA, bearing 190°T, distande 55,300 yds. With steady radar interference with S.J. characteristics steady on us. This interference stayed steady on us for 7 minutes while the radar operator was analyzing it and attempting to raise the SALMON in case it were she. (See comments on Radar).

16 October
0610 (I) Submerged in northern part of area in latitude 25° N and commenced patrolling east and west line.

1850 (I) Surfaced. Set course 180°T to close range on S.J. radar interference believed to be SALMON.

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Enclosure (A)

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16 October (Cont'd.)
2105 (I) Exchanged calls with SALMON.
2255 (I) Lieutenant Richard B. LANNING, USNR., executive officer of SALMON and two men aboard from rubber boat to exchange area information and movies. Borrowed two radar tubes which we were badly in need of.
2355 (I) Lieutenant LANNING and men departed in rubber boat. Continued patrol, Since surfacing, a searchlight was noticed playing on the clouds at frequent intervals throughout the night. This light was situated on IROKNOTO JIMA, and suggested that the Japs were flying planes in.

17 October
0610 (I) Submerged and commenced patrolling east and west line west of YOHAKUNI JIMA.
1200 (I) Surfaced to look around and see if there was any hot dope on the radio. All silent, so at
1211 (I) submerged and continued patrol.
1652 (I) Surfaced.
18 October
0615 (I) Submerged along latitude 25 N and commenced patrolling north and south line.
1858 (I) Surfaced.
19 October
0604 (I) Submerged on latitude 25-10 N and commenced patrol on course 070°T.

SHIP CONTACT #4. NOT ATTACKED.
SHIGURE CLASS DESTROYER.
LAT. 25-20N LONG. 122-37E

1055 (I) Sighted mast (SHIP CONTACT #4) range 10,000 yards, bearing 065°T. Battle stations submerged. As his tops came in sight saw he had a large port angle on the bow so changed course to 320°T and went ahead standard to close the track. He tracked at 15 kts., base course 265°T, constant helming, and was a big fat unescorted SHIGURE class DD, appertently heading for KURUN KO.

1027 (I) Range had decreased to 5600 yds., and we were on a normal approach course less bearing fast when he zigged right again and left us. At this time, several pings were heard, but he had not slowed so it was probably his fathometer. Range continued to open fast and at

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19 October (Cont'd.)
1108 (I) watched him go out of sight on the horizon on course 255°T, bearing 247°T, still heading for KURUN KO. Believed he might be an advance scout for something big coming later so determined not to be caught in the same spot twice, and took up patrol station along 25-16°N after sending contact report over wolfpack frequency to SILVER SIDES and SALMON.

SHIP CONTACT #6. NOT ATTACKED
2 ATAGO GA15, 1 NATORI CL, 2 DD LEADERS or CL15, SEVERAL FUBUKI DD12-48 E
LAT. 25-15 N LONG. 122-48 E

1328 (I) Sighted tops of several ships bearing 060°T, range 18,000 yds. Went to battle stations and commenced approach.

1332 (I) Sighted float type plane (PLANE CONTACT #17) circling ahead of convoy. 0/0 to 340°T, estimated range 16,000 yds., angle on bow 10 stbd. Course of 340°T was taken as it was believed task force would zig north just as DD had.

1334 (I) Angle on bow 30 Port; all ahead standard.

1337 (I) Angle on bow 60 Port and following ships were identified; 2 ATAGO class cruisers, 1 light cruiser and possibly 2 other light cruisers or destroyer leaders, and several FUBUKI class destroyers. (This is an estimate as only the tops of the superstructure were seen.) Took normal approach course.

1342 (I) Angle on bow 0, range 10,000 yds.

1344 (I) Plane was sighted 3,000 yds., angle on bow zero. Went to 70 feet between locks. Terpedo was heard passing along stbd. side. All stop.

1345-3C (I) Convoy was heard to zig right on sound gear and upon locking, we had 60 port angle on bow. From this time on, we lost bearing fast and range opened although we continued at standard speed on normal approach course.

1449 (I) Task Force I disappeared on horizon en course 270°T, bearing 300°T. Apparently we were sighted at 1342 by the plane. If we could have made 15 kts. submerged or had had a 10,000 yd. torpedo, we might have made it. To have 2 approaches in one day with such valuable ships get by, and not to be able to get within firing range even when we guessed his base course and zig plan, was discouraging to say the least, however, at

1522 (I) surfaced on course 245°T on 3 main engines, and sent contact report

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Enclosure (A)

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19 October (Cont'd.)
1552 (I) Cont'd.
to CONSUBPAC, info Third Fleet, thereby carrying out ergers to get
contact report off of any enemy task forces encountered (i.e., report
first, then attack). Tried to raise SILVERSIDES or SALMON, without
results.

1545 (I) Sighted wrecked Zero and parachute.

1625 (I) Had closed FORMOSA to 28 miles. Had plane over convoy still in
sight on SD at 16 miles. Plane contacts were getting too numerous,
so drove.

1900 (I) Surfaed.

1952 (I) Contacted SILVERSIDES. Received instructions to patrol area 6
miles north of PEITAU KAKU next day.

20 October
2615 (I) Submerged with PEITAU KAKU bearing 235°T, distance 12 miles, and
o/o to 270°T.

0916 (I) Sighted SILVERSIDES periscope bearing 004°T, distance 8,000 yds.

1045 (I) Received message on sound gear from SILVERSIDES that she was
clearing area on course 090°T, so changed course to 080°T with
PEITAU KAKU bearing 180°T, distance 6 miles.

1223 (I) Sighted plane (PLANE CONTACT #18).

1300 (I) Sighted plane (PLANE CONTACT #19).

1343 (I) Sighted 3 planes (PLANE CONTACT #20).

1350 (I) c/o to 150°T to keep the coast line in sight.

1500 (I) Sighted 3 planes (PLANE CONTACT #21).

1848 (I) Surfed ed en course 090°T.

1915 (I) Contacted SILVERSIDES and communicated with her on S.J. Roosevelt
instructions to cover approach to KURUN KO south of 25°-15° N.

21 October
1699 (I) Submerged and commenced patrol 6 miles northeast of PEITAU K.K.T.

1855 (I) Surfaced.

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Enclosure (A)

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22 October
0540 (I) Sighted HOKA SHO light, bearing 335°T, distance 22 miles.
0627 (I) Submerged and commenced patrolling east and west along 25-10° N.
1015 (I) Sighted plane (PLANE CONTACT #2).
1545 (I) Sighted 3 planes (PLANE CONTACT #23).
1850 (I) Surfacad.
23 October
0526 (I) Submerged 35 miles south of UOTSURI SHIMA.
1030 (I) Surfacad.
1108 (I) Sighted two flying boats (PLANE CONTACT #24). Dove.
1745 (I) Surfacad.
24 October
0200 (I) Contacted SILVERSIDES on S.J. radar, exchanged information.
0517 (I) Submerged with ISHIGAKI SHIMA bearing 160°T, distance 25 miles, course 320°T.
1259 (I) Surfacad; changed course to 190°T.
SHIP CONTACT #6. NOT ATTACKED. BUENOS AIRES AIRCRAFT - HOSPITAL SHIP. LAT. 25-16 N LONG. 123-50 E.
1400 (I) Sighted tops of ship bearing 246°T, distance 20,000 yds.
1403 (I) Submerged; battle stations; commenced approach.
1437 (I) With range 10,000 yds., and target tracking on steady course 050°T, speed 10 kts., target was identified as BUENOS AIRES MARU, properly marked hospital ship.
1451 (I) Took pictures and secured from battle stations.
1748 (I) Surfacad.
1945 (I) Contacted SILVERSIDES on S.J. radar.

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Enclosure (A)

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24 October (Cont'd.)
2106 (I) Rubber boat from SILVERSIDES with Lt. Comdr. C.F. LEIGH, USN., executive officer, and one man came alongside. Exchanged information, movies, and gave him some radar tubes.

2135 (I) Underway, patrolling station.

25 October
0560 (I) Submerged on course 045°T with ISHAGAKI SHIMA bearing 175°T, distance 20 miles.

1600 (I) Surfaced.

1730 (I) Sighted mast bearing 303°T - dove, commenced approach.

1754 (I) Identified target as U.S.S. SILVERSIDES. Discontinued approach.

1822 (I) Surfaced.

2030 (I) Contacted U.S.S. SILVERSIDES on S.J. radar. Received instructions to take stations for surface patrol next day at Lat. 23-35 N, 123-53 E. Changed course to 200°T.

2110 (I) Changed course to 180°T to pass between TARAMA JIMA and ISHIGAKI JIMA.

26 October
0230 (I) Changed course to 270°T.

0425 (I) Information contained in despatches from ROACH's RAIDERS indicated task force will pass to eastward of us, so changed course to 090°T and cut in 4 main engines on propulsion.

0456 (I) Changed course to 075°T.

0830 (I) APR indication of radar interference on 198 and 201 meg.

SHIP CONTACT #7. NOT ATTACKED.
TWO SHIPS - HEAVY TOPS - SEVERAL LIGHT TOPS.
LAT. 24-07 N LONG. 125-41 E.

0836 (I) Sighted tops of heavy ship bearing 060°T through high periscope, estimated range 25 miles. Commenced maneuvering for end around keeping range such that we would not be sighted. Almost immediately the tops of another heavy ship and 2 smaller tops were seen. The task force was plotting on course 040°T, speed 16 kts., and the possibility of a long end around looked good at this time. Continued maneuvering to get to eastward of task force while clearing contact.

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Enclosure (A)

— page 14 —
26 October (Cont'd.)

0836 (I)  Cent'd.
report to SILVERSIDES and SALMON on wolfpack frequency. (Ending around
to East had three advantages: (1) It placed task force between us,
SILVERSIDES, and SALMON; (2) Put task force between us and mine
field, and; (3) Ending around West would put us in sight of
MIYOKA JIMA before we could get ahead). Asked them to retransmit
to COUSUPAC for us. APR Indications were strong on 210, 197, and
147 meg (See comment on Radar), and one plane (PLANE CONTACT #26)
was seen over the task force.

0838 (I)  Message sent and receipted for by U.S.S. SALMON and U.S.S. SILVER-
SIDES. The bearing had been drawing steadily to the left and it ap-
peared we were doing all right on our end around. True bearing was
then 010°T.

0855 (I)  Range commenced to open rapidly with task force bearing 005°T.
Closed on true bearing.

0912 (I)  True bearing 003°T with target tips just visible and getting
smaller. That feeling of utter frustration that we know so well
is here again.

0925 (I)  Lost sight contact 350°T.

0950 (I)  Sighted smoke bearing 320°T - o/o to 320°T and cleared message to
SILVERSIDES giving him the latest dope. Task force was now on course
320°T, and had speeded up to 18 or 20 knots, and was apparently
heading for the slot between MIYAKO JIMA and TARAMA JIMA.

1040 (I)  No trace of the enemy had been seen for the last 50 minutes so
gave up the chase and came to course 130°T feeling completely
thwarted for the 4th time in 6 days. Had the HALIBUT's contact
report contained her position at time of sighted perhaps we could
have been in a better position - or interception at dawn, as this
error cost us 45 valuable minutes and was enough to cause us to miss
a position ahead.

1107 (I)  Sighted the SILVERSIDES.

1900 (I)  Received message from SILVERSIDES to patrol area C tomorrow.
Changed course to 270°T and proceeded for area assigned via pass bet-
ween YONAKUNI JIMA and HIJOMOTE JIMA.

27 October

0540 (I)  Radar contact bearing 085°T, distance 6,000 yds. Commenced
tracking.

0546 (I)  5 small pips on radar (SHIP CONTACT #8), and sight contact from
bridge identified them as samps.

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Enclosure (A)

— page 15 —
27 October (Cont'd.)

0610 (I) : Submerged at sunrise and commenced closing to investigate. Plotting and TDC showed them on course 240°T, speed 2 kts. Periscope now revealed they were under sail. Let them go booause of close proximity to land, and planned to look them up after dark.

0627 (I) : o/c to 120°T having decided to lock into ISHIGAKI HAKUCHI for anchored ships. IRIONOTE JIMA then bore 140°T.

0647 (I) : Sighted plane (PLANE CONTACT #26), distance 15 miles.

1326 (I) : Nothing in roadstead - o/c to 270°T to open coast.

1850 (I) : Surfaced.

2147 (I) : o/c to 180 to pass east of JONKUNI JIMA enroute area south of OKINAWA JIMA to cover southern approaches. 3 main engines on propulsion.

28 October

0243 (I) : o/c to 090°T with HADERUMA SHIKA bearing 000°T, distance 10 miles.

0637 (I) : Sighted periscope bearing 000°T, distance 2,000 yds. - avoided.

0916 (I) : Sighted plane (PLANE CONTACT #27). Dove.

1020 (I) : Surfaced on course 060°T.

1732 (I) : o/c to 070°T.

29 October

0627 (I) : o/c to 000°T.

0912 (I) : Sighted mast (SHIP CONTACT #9) bearing 359°T. Commenced approach.

1038 (I) : Submerged - Battle Stations.

1109 (I) : Identified targets as 6 tuna boats with two ex-whale "Killer" boats escorting. All too small for torpedoes. Commenced opening.

1255 (I) : Sent message to SILVERSIDES asking permission to battle surface.

1310 (I) : SILVERSIDES replied she had just picked up fresh oil slick and was following it. Changed course to joint SILVERSIDES.

1432 (I) : Surfaced on course 300°T.

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Enclosure (A)

— page 16 —
35 October

0500 (I) o/c to 105°T to head for rendezvous with SILVERSIDES and SALMON.

0530 (I) Received contact report from SALMON - c/c to 158°T at full speed to intercept.

0700 (I) Received message from SALMON giving OTC enemy position and stating she was making end around. Results negative.

SHIP CONTACT #9. ONE DAMAGED ONE LARGE CONVERTED TANKER, FOUR ESCORTS. LAT. 29-29 N LONG. 132-05 E.

0710 (I) Sighted tops of ships, bearing 205°T, visibility variable with rain squalls and haze. o/c to close and commenced tracking. Contact was large fleet tanker with 4 escorts. One escort was quite large, appearing to be an AK about 1/4 as big as the tanker. Due to variable visibility we had closed too much before sighting him, and the target challenged us.

0712 (I) c/c to 000 to open, and the convoy fell in astern of us, distance 10 miles.

0800 (I) Had finally worked our way out to 17 miles and had only his tops in sight bearing 230°T through periscope.

0805 (I) Enemy grew suspicious apparently, and changed base course to 070. Maneuvered to get ahead again.

0900 (I) In position ahead about 17 miles. Enemy changed base course to 340°T, thereby throwing us on his beam again. Proceeded to get back ahead at full speed.

1020 (I) Ahead in position - enemy changed base-course to 020°T. Proceeded to get ahead again at full speed. This convoy was smart. We have to stay 15 to 18 miles ahead to stay out of sight, and his changes of base course were just irregular enough to prevent our pre-estimating a place to dive. Each base course change had placed us on his beam necessitating a long full power run to get ahead again.

1125 (I) Received message from SILVERSIDES saying she had attacked with 1 premature.

1200 (I) Sighted SALMON on bearing 200°T, range 10 miles.

1330 (I) Target disappeared in rain squall - bearing 265, manned S.J. radar.

- 16 -

Enclosure (A)

— page 17 —
30 October (Cont'd.)

1403 (I) Radar bearing 229°T, range 28,000 yds., showing he had zigged to 160°T. He had changed 140° in base course after entering rain squall. This bearing in a heavy sea and heavy rainstorm was a combination of luck and skill. Sent contact messages for which no one received. Commenced closing at high speed on his normal approach course. With range 15,000, convoy o/o to 040°T. We were on reverse bearing. Rain lifted and we drove. A long persistent chase had been rerared. We finally had the rat cornered - now we'll see how he fights. Weather was roughening up with waves 6 to 8 feet in height. We were headed into the sea and wind and had difficulty holding depth at 60° (broached to 36 feet once but not sighted.). When targets came into sight in periscope, four escorts were seen, one being a small freighter. The big tanker was zigging back and forth in center of escorts which were arranged on each quarter. Escorts would zig about once for each of 2 zigs of the tanker making the approach damn difficult.

1558 (I) Range 4600 on tanker, angle on bow 10 Port on 2 starboard escorts, and 5 Starboard on tanker, came to 160°T, 45°s to his course to open track intending to fire high parallax if he did not zig back, or gambling on a zig to his right if he did zig at all.

1600 (I) With range 4400, periscope dipped just as target was beginning a zig to his right. He gave us a 45 port angle which was a perfect set up for the bow tubes except for the range, which would be long. It was now or never, though. The port escorts were pinging on us with angles on the bow of 10 Port and zero.

1605 (I) Maneuvered around escort who was pinging on us, zero angle on bow.

1609 (I) Unable to see target as escort was in way.

1610 (I) With range 4,000 yds., angle on the bow 90 port and torpedo run too great, commenced firing the bow tubes gambling on one of them having a long run. We were firing into the wind and sea. (Just prior to firing at the tanker, one escort had crossed our bow and we almost fired at him, all fish being set on 4 feet. We let him go by, however, and there was not time to change the depth settings back to greater depth). One torpedo broached all the way down the range alerting the tanker who zigged left, toward us, swinging fast. We were swinging right and settled on course 270°T. The tanker headed across our stern on course 000°T at increased speed. All forward tubes had missed.

1615 (I) Commenced firing after tubes with range 1400 yds., angle on bow 9, course 000°T, speed 14 knots. 2 minutes later heard first torpedo hit. Raised scope and observed 2 more hits, all in stern which was obliterated by smoke and flying debris. Smoke cleared to show a portion of the stern gone. His screws stopped never to turn again. Fourth fish hit, but I was looking at an escort who had turned toward

- 17 -

Enclosure (A)

— page 18 —
30 October (Cont'd.)
1615 (I) Cont'd.
us with a zero angle on bow and a bone in his teeth. Retired to safer depth, 320 feet, where our inductions would be safer, and while passing 120 feet heard a tremendous explosion which was not a depth charge, and which rumbled and crackled for about 20 seconds to the accompaniment of heavy minor explosions. While going deep, 3 more escorts joined the chase, and as we hit 200', the first escort made a beautiful run and dropped a pattern over us followed by other escorts in quick succession. The 4th escort, presumably the AK, stayed off to the side apparently coaching. The encirclement method was employed, and we were boxed in very quickly. A 3 degree negative temperature gradient was found starting at 250 feet. Stayed at standard speed heading for escort who had made the last run. This course was into the wind and sea and away from the tanker, giving the SALMON a chance to get in and finish the tanker or AK. Slowed to 2/3 speed, which was maintained throughout the evasion tactics. During the next hour, 78 depth charges were dropped, all pretty close, screws were heard on at least two runs passing overhead, once close aboard down the stab side, and the rest astern.

1730 (I) Escorts were falling slowly astern, our course 150T, so made reload and started up only to have one escort start toward us.

1800 (I) Started up again.

1855 (I) Surfaced. 3 pips on radar at 15,000 yds., bearing 300°T. We were in the moon slick but luckily had a bad horizon behind us. Headed north with two engines on charge and two on propulsion to get in position for another attack if opportunity presented itself. Antenna trunk was flooded out, so we had only the S.D. radar mast, and sent out serial four to COMMERAC, and reports to other submarines on wolfpack frequency. Received no reply. During this time, we were getting snatches of messages showing that SALMON, SILVERSIDES, and STEELER were making a coordinated attack. Held off closing to get more dope on their positions.

2140 (I) Saw gunfire bearing 180°T. Unable to raise SALMON or SILVERSIDES. Commenced closing gun flashes. Picked up'S.J. radar interference ahead. Challenged on S.J., but got no reply. Decided to go around this stranger, but he was between us and the gun flashes and it was a long process. This sub was later identified as the STEELER proceeding towards target. STEELER reported putting 4 hits in tanker we had hit. Why it didn't sink before, with that tremendous explosion; we will never know. Sent latest dope to COMMERAC and all submarines.

- 16 -

Enclosure (A)

— page 20 —
31 October (Cont'd.)
2341 (I) Cont'd.
since 2200 but were unable to contact her.

1 November
0010 (I) STERLET reported 2 torpedoes heading north. All ahead emergency to avoid. Sighted wakes from bridge passing astern of TRIGGER and ahead of STERLET who was bearing 250°T at the time. Commenced closing area. Sent message to SILVERLINES, but it was not receipted for.

0059 (I) Lookout sighted torpedo wake on stab beam passing aft. Avoided. Decided this was a very unhealthy area so decided to clear it at SALMON's best speed and send rendezvous message to SILVERLINES following night if she didn't show up before. Set course 157°T to head for SAIPAN safety lane at 16 kts.

0065 (I) Lieutenant LAKING and men left ship in rubber boat. TRIGGER screening on port bow and STERLET on starboard bow of SALMON.

0627 (I) SILVERLINES sighted bearing 270°T, distanced 10 miles.

0730 (I) Received instructions from SILVERLINES to take position ahead, distance 10 miles. Commenced opening range to look for Picket boats and aot as. bait.

1417 (I) Sighted plane (PLANE CONTACT #28) bearing 270°T, range 6 miles. Dove. On the way down received message from "buck" saying we had air coverage on our port beam. Surfaced. Continued enroute SAIPAN with air coverage.

2 November
0803 (I) Air coverage arrived (PLANE CONTACT #29). A total of 5 planes showed up during morning.

1730 (I) Air coverage departed.

1800 (I) o/c to 133°T.

1900 (I) Green flare, radar interference on SFR, and pip on S.J. at 20,000 yds. Exchanged recognition signals with 2 friendly planes.

3 November
0840 (I) Rendezvoused with U.S.S. ELLET.

2030 (I) Moored alongside of U.S.S. HOLLAND, outboard of STERLET in TANAP HARBOR, SAIPAN.

- 20 -

Enclosure (A)

— page 24 —
U.S.S. TRIGGER - Report of War Patrol Number TEN (Cont'd.)

(A) AIRCRAFT CONTACTS: (Cont'd.)

CONTACT NUMBER | 8 | 9 | 10 | 11 | 12 | 13 | 14
---|---|---|---|---|---|---
Date | 8 Oct. | 9 Oct. | 10 Oct. | 11 Oct. | 12 Oct. | 13 Oct. | 14 Oct.
Time (Zone) | 1415 | 1030 | 2158 | 0705 | 0710 | 0715 | 0920
Position, Lat. | 121-12N | 122-49N | 124-24, 8125=0TN | 125=0TN | 125=08.5, 125=16.2
Long. | 133-55E | 125-50E | 122-21E | 122-16E | 122-28E | 122-01E
Speed | 17 | 17 | 7 | 6 | 11 | 3 | 3
Course | 189 | 286 | 035 | 270 | 270 | 180 | 300
Trim | Sur. | Sur. | Sur. | Sur. | Sub. | Sub. | Sub.
Minutes Since Last SDR Radar Search | 1 | 1 | 1 | 1 | 1 | 1 | 1
Number: | 1 | 3 | 1 | 1 | 1 | 1 | 2
Type | Single | Single | IWR:Eng, IWI:Eng, IBetty | IWI:Eng, IZI:Eng, IZeke | IZI:Eng, IZeke
Probable Mission | Unk | Unk | Patrol Patrol Patrol | Patrol Patrol | Unk
How Contacted | 1 | 1 | 1 | 1 | 1 | 1 | 1
Initial Range | 5000 | 5000 | 6000 | 12000 | 6000 | 10000 | 10000
Elevation Angle | 15° | 65° | 5° | 10° | 5° | 30°
Range & Relative Bearing of Plane When It Deployed S/M | 1 | 1 | 1 | 1 | 1 | 1 | 1
(Slate (Beaufort) | 3 | 3 | 3 | 3 | 3 | 4 | 3
Sea (fort) | 300 | 300 | 300 | 235 | 235 | 235 | 235
Visibility (lat) | 20 | 20 | 5 | 20 | 20 | 10 | 10
Clouds (F) | 300 | 3000 | 5000 | 5000 | 5000 | 5000 | 3000
Overcast | 20% | 20% | 60% | 30% | 30% | 40% | 20%
Moon (Angle) | 1 | 1 | 1 | 1 | 1 | 1 | 1
(Parent Illum. | 1 | 1 | 1 | 1 | 1 | 1 | 1

- 24 -

Enclosure (A)

— page 26 —
22 23 24 25 26 27 28
Date: 4 4 4 4 4 4 4 4
Time (Zone): 1015 1545 1108 0900 0647 0916 1417
Position: Lat. 25-19 N 25-17 N 25-15 N 24-07 N 24-38 N 23-43 N 23-49 N
Long. 122-10E 112-17W 124-05W 125-41E 123-35E 124-47E 137-30E
Speed 3 3 3 3 3 3 3 3
Course 305 100 060 075 120 090 155
Trin. Sub. Sub. Sur. Sur. Sub. Sur. Sur. Sur.
Minutes Since Last SD Radar Search 36
Number 1 1 1 1 1 1 1 1
Type 1 1 1 1 1 1 1 1
A 1 1 1 1 1 1 1 1
I 1 1 1 1 1 1 1 1
R 1 1 1 1 1 1 1 1
C 1 1 1 1 1 1 1 1
R 1 1 1 1 1 1 1 1
A 1 1 1 1 1 1 1 1
F 1 1 1 1 1 1 1 1
T 1 1 1 1 1 1 1 1
Initial Range 10000 10000 15000 30000 18000 18000 12000
Elevation Angle 5° 5° 1° 5° 5° 5° 3°
Range & Relative Bearing of Plane When It Detected S/M
C 4 3 3 1 1 2 1
C 4 3 3

— page 27 —
29 30
Date: 12-Nov. 12-Nov.
Time (Zone): 0803. 1905
Position: Lat. 20-01N 17-50N
Long. 139-56E141-08E
Speed: 16 15
Course: 155 133
Trin. Sur. Sur.
Minutes Since Last SD Radar Search: - - -
Number: 2 2
Type: PB-2Y LIBER. 10th Air/10th Air
Probable Mission: 20,000 20,000
Initial Range: 20000 20000
Elevation Angle: 3° 1°
Range & Relative Bearing of Plane: - - -
When It Detected: - - -
C/M: - - -

(C) State (Beau- | 1 1
Sea: (fort) 1 1
(Direction(Rel): 090 090
Visibility (Miles): UN UN
(Hoight in: 10000 10000
Cloud: (Percent 5% 5%
Overcast (Rel) 5% 5%
Moon(angle 5%
Percent Illum.
Enclosure (A)

— page 28 —
U.S.S. TRIGGER - Report of War Patrol Number TEN (Cont'd.)

(H) ATTACK DATA:
Torpedo Attack No. ONE. Patrol No. TEN.
Time: 1615 (I) Date: 30 October Lat. 30-14 N, Long. 132-50 E.

TARGET DATA - DAMAGE INFLICTED:
Large fleet tanker escorted by 3 torpedo patrol boats and one 2500 ton AK. Ship contacted at 0730 by high periscope watch in good visibility after SALMON had sent out contact report.

Ship(s) sunk: None.
Ship(s) damaged or probably sunk: One large AO.
Damage determined by: 2 observed hits in stern followed by 2 timed hits.
Target draft: 20 ft. Course: 100 Speed: 14 Range: 4000 1400 000

GUN SHIP DATA:
Speed - 3 kts. Course - 180 Depth - 65 Angle - 120P 270 90P

FIRE CONTROL AND TORPEDO DATA:
The bow tubes were fired on 120P track, but excessive range caused misses/astern. One or more torpedoes broached causing target to zig aeroes our stern. 4 stern shots were then fired, all of which hit aft.

Tubes Fired 6 5 4 3 2 1
Track Angle 114° 116° 116° 117° 118° 119°
Gyro Angle 348° 343° 341° 346° 347° 336°
Depth Set 4 ft. 4 ft. 4 ft. 4 ft. 4 ft. 4 ft.

Power
Hit or Miss Miss Miss Miss Miss Miss
Erratic No Broadband Broadband Pos. Bro. Pos. Bro. Pos. Bro. Pos. Bro.
Mark Torpedo 18-1 18-1 18-1 18-1 18-1 18-1
Serial No. 56268 56229 56209 56200 55607 55194
Mark Exploder 8-5 8-5 8-5 8-5 8-5 8-5
Serial No. 8821 10243 10158 9812 9045 9860
Actuation Set Contact Contact Contact Contact Contact Contact Contact
Actuation Actual Contact Contact Contact Contact Contact Contact
Mark Warhead 18-2 18-2 18-2 18-2 18-2 18-2
Serial No. 2311 2025 2612 3210 2419 2213
Explosive Torpex Torpex Torpex Torpex Torpex Torpex
Firing Interval 8 sec. 8 sec. 8 sec. 8 sec. 8 sec. 8 sec.

Sea conditions State 4 State 4 State 4 State 4 State 4 State 4
Overhaul Activity
Remarks Fired into Wind and Sea.
Torpedo Run 3750 3750 3750 3750 3750 3750

- 28 -

Enclosure (A)

— page 29 —
U.S.S. TRIGGER - Report of War Patrol Number TEN (Cont'd.)

(H) ATTACK DATA (Cont'd.)

FIRE CONTROL AND TORPEDO DATA (Cont'd.)

Tubes Fired 7 8 9 10
Track Angle 100°P 102°P 108°P 110°P
Gyro Angle 173.5° 164.5° 157° 167.5°
Depth Set 4 ft. 4 ft. 4 ft. 4 ft.
Power
Hit or Miss Hit Hit Hit Hit
Error No No No No
Mark Torpedo 18-1 18-1 18-1 18-1
Serial No. 55158 55140 55665 56481
Mark Exploder 8-5 8-5 8-5 8-5
Serial No. 8721 9841 9129 8752
Attuation Set Contact Contact Contact Contact
Attuation Actual Contact Contact Contact Contact
Mark Warhead 16-2 18-2 18-2 18-2
Serial No. 1510 2344 3061 3547
Explosive Torpex Torpex Torpex Torpex
Firing Interval 8 sec. 8 sec. 8 sec. 8 sec.
Type Spread
Sea Conditions State 4 State 4 State 4 State 4
Overhaul Activity SUBMARINE BASE, PEARL HARBOR
Remarks Fired Aircraft
Torpedo Run 1350 1375 1400 1400

(I) MINES: Not applicable.

(J) ANTI-SUBMARINE MEASURES AND EVASION TACTICS:

The enemy counter-measures encountered on the attack of 30 October were very good during the first phase. Immediately after the first torpedo explosion, one escort made a beautiful run directly over us and dropped about 7 charges overhead as we passed 200 feet. Settled at 320 feet. Escorts continued running on us until a total of 70 charges were dropped, each pattern falling progressively farther astern. Immediately after the first pattern, a string of about 20 light explosions were heard at about 1 second intervals. The encirclement method was used with 3 escorts circling and pinging and one listening. We held 2/3 speed and a southeasterly course between changes of course to put tail to attacking escort, and after two hours, put escorts astern. S.E. course was into wind and sea. Negative temperature gradient was 3° with a good layer at 320 feet. Predicted echo range was 1700 yds. at 320 feet. Course drew escorts away from crippled tanker, but evasion tactics were too successful as escorts were back at tanker at 1915 in time to detect the SALMON making an approach. These escorts had no radar, however, radar was used by the heavy ships encountered on 26 October.

It is worthy of note that the float plane over the Task Force on 18 October sighted and fired a torpedo at us.

- 29 -

Enclosure (A)

— page 36 —
35237/A16-3
Serial: 034
C-0-Z-F-I-D-Z-I-T-I-A-L
From: The Commander, Officer, The Commander in Chief, United States Fleet.
To: The Commander Submarine Division 102.
Via: (1) The Commander Submarine Squadron TDN.
(2) The Commander Submarine Force, PACIFIC FLEET.
(3) The Commander Submarine Force, PACIFIC FLEET.
(4) The Commander in Chief, U.S. PACIFIC FLEET.

Subject: Addenda to Report of U.S.S. TRIGGER War Patrol Number TEN.

Enclosure: (A) Subject Report.
(B) Track Chart (To CombSue only).

1. Enclosure (A) covering the second part of this vessel's TURN War Patrol to the east and north of the MONTH IOLAD during the period from 10 November to 23 November 1944, is forwarded herewith.

P. J. HAMILTON, II.
U.S. NAVAL HISTORICAL COMMITTEE
[signature]

— page 37 —
10 November 1944

1620 (I) Underway from TAPAG HARBOR, SAIPAN, in company with SAUV, TAMBO, SILVERJIDDS, BURFISH, HONQUILL, STERLET, and 3-SUGO, in accordance with Commander Task Group 17.2, supplementary patrol instructions dated 9 November, 3-0.P.A. - Commander Task Group 17.2 in SILVERJIDDS, being escorted by U.S.S. CAUTION.

2143 (I) Escort departed. Entered eastern end of FUNNEL. 0/0 to 311ST.

11 November

Surface cruising, battlesurface drills.

2306 (I) At Western end of FUNNEL, 0/0 to 355ST, and took station in scouting line, distance 14 mile 5; order of ships from right to left - SAURY, TAPBOR, TRICOBER, SILVERJIDDS, STERLET, BURFISH, and RONQUILL. RESCUED departed formation and proceeded independently.

12 November

1005 (I) Sighted plane (PLAN CONTACT #1). Exchanged recognition signals.

1040 (I) Radar signal, 193 megacycles, on SIR. Radar officer held his ground that this was friendly ship from radar, and at

1055 (I) Proved himself right when a friendly Task Force (SHIP CONTACT #1) consistently of approximately 3 cruisers and 5 destroyers, was sighted bearing 0600T, distance 18 miles. The SPR-SPA has certainly proved its worth. It has, on 2 separate occasions on this patrol, given advance notice and, identification of the arrival of major task forces, one Jap and one friendly, as well as numerous plane contacts. It is definitely worth its weight in gold. No notification of the passage through our area of this task force had been received.

-1- Enclosure (A)

— page 38 —
12 November (Cont'd.)

Contacted touchdown base (?) of Task Force on VHF; informed him 2 friendly subs were either surface or submerged in front of friendly Task Force.

Next two hours were hectic as many planes, one Liberator in particular, of Task Force umbrella, Apparently not having word of subs, made frequent unfriendly approaches.

13 November

1000 (I) Entered assigned patrol lane and commenced steering various courses to give maximum area coverage.

14 November

1145 (I) Sighted plane (PLANE CONTACT #2). Dove.

1258 (I) Surfaced.

15 November

0550 (I) Received contact message from SILVERSHIPS giving information on patrol boat. c/c to close.

1620 (I) Sighted periscope on horizon. 1022 Periscope disappeared.

1104 (I) Sighted submarine surfacing. Exchanged calls with ARCHERFISH who was proceeding to lifeguard station.

1225 (I) Sighted gunfire on horizon. This was STRELETBATTLEING PATROL BOAT (SHIP CONTACT #2). Closed.

1237 (I) STRELET dove.

1256 (I) Sighted SILVERSHIPS bearing 320°T.

1300 (I) STRELET surfaced.

1327 (I) Commenced closing target in line of bearing with SILVERSHIPS and STRELET, using VHF for communication.

1357 (I) Quartermaster sighted periscope close aboard to port. Took evasive course to, work our way around it. Later decided, after sighting several empty shell cases in water, that the periscope had been one of the same. Our apologies to the SILVERSHIPS and STRELET for unduly alarming them.

- 2 -

Enclosure (A)

— page 39 —
15 November (Cont'd.)

1512 (I) Had closed target to 3,000 yds. He was a small net tender and had been running away during our approach at approximately 12 kts. Commenced firing with STERNES and STERNITES, with SILVERSTONES astern of target, STERNET on target's stern, turret and TRICER on port quarter. Target commenced maneuvering radially, and returning fire when range was 7,000 yards, and secured several attacks on us. At 5,600 yards, heavy strafights were all around. Disembarked to keep out of his range which appeared to be around 6,800 yds., and continued firing with 4". The 4" gun shooting was heartbreaking. Using radar ranges and high periscope spotting, we scored many near misses, several times splashing him with water, but we could not hit.

1605 (I) Out of 4" ammunition, having fired 112 rounds. Tracking target evading instructions. Closed STERNET to communicate with VHF end received dope that SILVERSTONES had subarqued for torpedo attack; TRIGGER to draw target to northeast. Charged course to comply. Shortly thereafter, SILVERSTONES surfaced and ordered us to resume normal patrol. Communication on VHF could not be established at this time, so spent 1 hour closing SILVERSTONES and requested permission to try torpedo attack. Permission issued was granted, and at

1611 (I) Charged course to 255 to regain contact.

2150 (I) Heine thoroughly searched area and not having received contact, charged course to 0650 to regain position in search-lines. Time wasted in establishing VHF communications resulted in target's escape.

16 November

0145 (I) Received TAMOR contact report and changed course to intercept.

0925 (I) Sighted gun flash bearing 1580' and changed course to close.

0700 (I) Arrived at scene of attack just in time to see TAMOR sink the Patrol vessel (SHIP CONTACT #3). While approaching we thought we saw a direct hit scored on TAMOR.

0716 (I) Charged course to regain station in own lane. TAMOR needed no assistance.

1955 (I) Received SAVRY contact report of 2 patrol boats, c/o to intercept.

- 3 -

Enclosure (A)

— page 40 —
16 November {Cont'd.}
2304 (I) Radar contact on SAURY bearing 1700T, distance 12,700 yds. o/c to 1700T. Received latest information on targets from SAURY. Commenced tracking. Visibility was very poor and sea fairly rough. SAURY ordered no torpedo or gun attack until dawn.

17 November
0045 (I) Radar contact, 2 small pips (SUIT CONTACT #4).
0705 (I) Submerged ahead of to port for submerged attack having arranged with SAURY to approach from stab, side. Targets had tracked all night at speed 4 kts., course: 335.
0810 (I) Targets not in sight so surfaced to continue search. Heavy rain had set in.
0813 (I) Sighted targets bearing 1100T, distance 5 miles - submerged and commenced closing.
1115 (I) Only 1 target in sight. No was lying to and appeared to be on course. Decided to try torpedo attack as target appeared to have 3" (?) gun and we had no 4" ammunition.
1135 (I) Fired one electric torpedo with range 1200 yds., gyro angle zero, speed 3 kt. to allow for drift, depth set 2 foot, angle on bow 90 stab. Seas force four, firing down wind. Missed, so set.
1137 (I) Fired another with same setup. Missed.
1140 (I) Reversed course.
1142 (I) Hard on end of run explosion. The target had shown no signs of life even after the end of run explosion.
1154 (I) Fired one electric from stern tubes, range 2400 yds., gyro zero, speed 1 kt., angle on bow, zero. Missed.
1200 (I) Hard on of run explosion. Still no activity on the target. Scoured from battle stations and commenced opening range.
1405 (I) With range 12,000 yds., surfaced and commenced tracking - 2 targets spar in sight. They were both underway again.
1520 (I) Aimed 40 M, 20 M's and 50 cal. and commenced closing from eastern on 4 engines to attack. With range 8,000 yds., targets sighted us and took evasive action. Things wore going fine until

-4- Enclosure (A)

— page 41 —
17 November (Cont'd.)

154C (I) when plane (PLATE CONTACT #3) appeared on SD radar at 16 miles close in fast, so submerged. Where this plane came from will always be a mystery. He certainly caused enough damage to us, however, as we were forced to dive with all guns mounted and all ammo exposed.

1712 (I) Surfaced on course 060.

1925 (I) Exchanged calls with SAURY. Continued search for patrol vessels.

2200 (I) Received Pref Commander message directing sweep to discontinue, to proceed CIAR, to request routing instructions from COSTURPAC.

230C (I) e/o to 1500m. The water gyro, radar, and radio equipment, 11 simultaneously went out of commission. The radar was intermittently out of commission for the remainder of the night.

18 November

0045 (I) Heard distant explosions.

0155 (I) Radar contact on SAURY who was searching for t-nuker. We had missed SAURY messages on t-nuker.

0225 (I) Radar contact 4,000 y-ras - two patrol vessels. Avoided and continued search for damaged t-nuker unknown to ourselves. (This contact plotted very near static to position of two p-trol boats that we had last seen at 1600).

0230 (I) Auxiliary gyro stashed down.

0310 (I) Exchanged calls with STREET who had joined search.

0458 (I) STREET reports finding some 2 p-trol boats, but no t-nuker.

0526 (I) SAURY reports losing all contact, 1 hit in tanker. Discontinued search, set course 130 for 22 h east side Dunkers Dummy. The tanker had not escaped in our section from 0700 to 2000, and as we had approved from northwest just before SAURY fired, he did not secure in that direction.

1030 (I) Changed course to 1800T.

19 November

0216 (I) Changed course to 1400T.

- 5 -

Enclosure (A)

— page 42 —
20 November
0500 (I) Changed course to 1300T. Weather very rough and had reduced speed to 1 M.E.

1250 (I) Plane contact on radar 8 miles. Closed to 3500 yds., but visibility was 1000 yds., and he was not seen. At this same time, radar interference was picked up in the SFR-SPA on 3 Jap frequencies (See comments on Radar). This interference persisted until about 1800.

21 November
1200 (I) Sea began to moderate. Commenced making s/s on 2 main engines.

1229 (I) Changed course to 2550T.

1555 (I) Made landfall on SAITAN ISLAND, range 40,000 yds., c/c to head for rendezvous position at end of safety line.

22 November
0410 (I) Rendezvoused with U.S.S. SWANSON, circling on station writing arrival of SPEARFISH and BLENNY.

1000 (I) Changed course to 1900T.

1300 (I) PLENTY and SPEARFISH left formation for SAIPAN.

23 November
0607 (I) Passed through torpedo net.

0640 (I) Moored stbd side to SPERRY, ARA Harbor, GUAM.

- 5a - Enclosure (A)

— page 44 —
1 2 3 4
Date: 12 Nov. 14 Nov. 17 Nov. 20 Nov.
Time (Zone): 100°(I) 1145(I) 1540 I 1240 I
Position: Lat. 20-54.5N 28-23N 31-15N 19-31N
Long. 138.45E 136-39E 141-22E 147-04E
Speed: 15 13 15 7
Course: 332 045 150 180
Train: Sur. Sur. Sur. Sur.
Minutes Since Last
SD Radar Search
Number: 1 2 1 1
Type: B-24 Bomber
Probable Mission: Patrol
How Contacted: Sight Radar Radar
Initial Range: 13 mi. 10 mi. 13 mi. 12 mi.
Elevation Angle: 180 20
Range & Relative
Bearing of Plane
When It Detected
S/M

| State (Beau- | Sec: (fort) | 2 | 3 | 4 | 6 |
|: | : | : | : | : | : |
| Direction (Rel) | 750 | 340 | 060 | 315 |
| Visibility (Miles) | 20 | 15 | 15 | 1 |
| Cloud: (ft) | 1600 | 1600 | 1500 | 1000 |
| (Percent Overcast | 40% | 50% | 60% | 100% |
| Angle | | | | |
| Moon: (Percent | | | | |
| (Illum. |

— page 45 —
(H) ATTACK DATA:
    TORPEDO ATTACK REPORT FORM
    U.S.S. TRICKER
    Time: 1135 I
    Torpedo attack no. ONE PATROL NO. TEN
    Date: 17 November 1944
    Lat. 31-10 N., Long. 141-30 E.
    TARGET DATA - DATABASE INFLICTED
    Description: Small patrol craft, similar to Tuna Boat.
    Ship(s) sunk: None.
    Ship(s) damaged or
    probably sunk: None.
    Damage determined by: No damage.
    Target draft: 5 ft.
    Course: 265°T.
    Speed: 0 kts.
    Range: 1200 yds.
    Stern: 270 yds.

ON SHIP DATA
Speed: 4 kts.
Course: 175°T.
Depth 64 ft.
Angle: 60°.
025°T.

TITLE OF TORPEDO DATA
Type attack: This was a daylight submerged surface attack.
Tubes fired: 1
Tracks: 1
Gyro angle: 90° S
Depth: 2 ft.
Depth: 2 ft.
Power: 2 ft.
Hit or Miss: Miss
Ere-time: No
Mark Torpedo: 1-1
Serial No.: 55787
Suit Exploder: 4-2
Suit No.: 10073
Actuation Set: Contact
Actuation Actu: 13-2
Mark Reached: 13-2
Serial No.: 1037
Explosive: Torpex
Firing Interval: None
Type Spread: None
Sea Conditions: None
Overall Activity: 4
Remarks: SUMARIZE BASE, FINAL HARD
End of Run: None
End of Run
Explosion: None
Explosion

Enclosure (A)

— page 46 —
7
Addenda to Report of U.S.S. TRIGGER War Patrol Number TMN(Cont'd.)

(I) MINES:
No comment.

(J) ADJUST-SURFACE MEASURES AND MATCHES:
No comment.

(K) MIZOR DETECTS AND DETACH:
No comment.

(L) RADIO:
No comment.

(M) HEADER:
SJ gear operation was only fair. After run attack on Patrol boat, much maintenance work was required to maintain normal operation. Voltage surges from I.V. power source blew fuses on two cox-sions while gear was in operation and on the second cox-sion literally blew up the ZXZ tube in the Range Indicator. During gun attack on Patrol boat SJ was used for ranging and spotting. Sides were frequently shot and always on an intermittent basis.

SD gear used infrequently and only on an intermittent basis. Only routine maintenance work was required.

SH-SFA gear used continuously on TORI SHIPS, ISLAND or 146 mogs, 6 u.s. pulse length, 60 P.R.P. We were not picked up by this radar. Several U.S. contacts were made, one from a Task Force 15 minutes before sighting masts at 20 miles range.

(N) SOUND GEAR AND SOUND CONDITIONS:
No comment.

(P) HEALTH, FOOD, AND HYGIENICITY:
No comment.

(Q) PERSONNEL:
No comment.

(R) MILES STEADED - FUEL USED:
Ships to area 855 Mi. 8,780 Gals.
In area 1450 Mi. 19,430 Gals.
Area to Guam 1200 Mi. 15,200 Gals.

Total 3505 Mi. 43,410 Gals.

Enclosure (A)

— page 47 —
3
Days in area: 5
Days around Guam: 13

(T) FCTORS OF INFLUENCE REMAINING:
Torpedoes: 11
Fuel: 44,100 (at Guam)
Provisions: 30 days
Personnel: 20 days
Total: 74 days

Imitate factor this patrol - Swamp discontinued on orders of CONSULTER.

(U) REMARKS:
The commanding officer feels that, due to the improvements encountered in previous anti-submarine warfare, the following characteristics are best becoming a necessity in submarine construction: (1) ability to dive to 800 feet; (2) surface speed of 27 kts., and submersible speed of 12 knots; (3) installation of double rudder to facilitate quick turns submerged; (4) Development of a riser-type depth induction (SCHNORCHEL) developed, similarly with the present free floating induction in place. Item (4) seems to be the only feasible method to combat the improvements not in shore-based radar in the vicinity of important ports which are taking an undetected approach to enemy ports more than 100 miles distant. In addition, night flying radar planes and persistent long-held down searches will be, in effect, nullified.

The establishment of a submarine C.I.C., in central listening area, with power to strategically shift and station all packs immediately so the situation changes, is suggested. This advanced sub air force, would be able to make the most of the enemy's situation. The possibility of the enemy's ability to move forward and strike the enemy fleet is not considered. Individual sub air force would be reduced to minimum. It is suggested that the NAMURUS, NAPWIL, BAS3, BAHACUDA, and BONITA, could be fitted out as C.I.C. submarines.

The TRIGGER was dropped during its gun attack on this patrol by the TCT to the gun was situated aft. The best solution to the problem is the installation of a 5" gun forward and aft. The 40 MM shells should have a range of 8,000 yds. before self-destruction.

- 10 -

Enclosure (A)

— page 48 —
05-10/416-3
Serial 0254
CONFIDENTIAL

PILOT ADDRESS: 00 THICKER Itr. SS237/416-3/Serial 033 or 3 Nov. 1944.

From: The Commander Submarine Squadron Ten and the Commander Submarine Division 101.
To: The Commander in Chief, United States Fleet.
Via: (1) The Commander Submarine Force, Pacific Fleet.
(2) The Commander-In-Chief, U.S. Pacific Fleet.

Subject: U.S.S. THICKER - Report to Captain Number TEN.

1. The Tenth War Patrol of the THICKER consisted of two patrols. The first was the customary submarine war patrol, during which THICKER was one of three submarines in a well-pack, in company with SILVERSTONES and SALMON, and included two days of lifeboat duty near FORNOCA. Upon completion of the first phase, THICKER spent a week at SABINE getting ready for the second. During the second phase, THICKER was one of seven submarines, organized to make an anti-petrol vessel sweep to the east and north of the SOUTH ISLAND. The other six submarines were SLIMMESD, MURPHY, RONALD, SAVOY, and TARBOR.

FIRST PHASE

2. During the first phase, THICKER was fifteen days enroute her area, twenty-one days in area, and three days enroute from area to CAPITAL. Ten torpedoes were fired and four hits registered in a large tanker (which was subsequently attacked by both ROCKY and SPIRIT, and sunk). No other torpedoes were fired during the patrol. Four worthwhile contacts were made, all during daylight, as follows:

(a) A SINGLE Class Destroyer on 19 October - Because of relatively positive wind shifted and because of the destroyer's speed and radical changes of course, THICKER was unable to gain attack position, but suspected that this destroyer was an advance scout for a larger force. This proved to be the case, and five hours later resulted in contact with

(b) An enemy task force of two CA's, one CL, and several DD's - THICKER surmised that this task force would follow the same zig-zag path that the DD had, and commenced approach accordingly, but about thirty minutes after the task force was sighted, a

— page 49 —
7/5-10/16-3
Serial: 0254
CONFIDENTIAL
Subject: U.S.S. TRIGGER - Report of War Patrol Number TGT.

---

**Note:**
- The text is a transcript of a submarine patrol report.
- The report is dated 7/5-10/16-3.
- The report is from the USS TRIGGER.
- The report is classified as TOP SECRET.
- The report was written by a crew member named TRIGGER.
- The report was sent to the USS TRIGGER.
- The report was received by the USS TRIGGER.
- The report was sent

— page 50 —
3. TRIGGER participated in one gun attack on a small net tender with SILVERSDIGS and STARLET on 15 November, firing a total of 112 rounds of four-inch ammunition at a range of about 7,000 yards. No hits were scored, and the attack was broken off to enable the SILVERSDIGS to deliver a torpedo attack. On the morning of 17 November, TRIGGER made a submerged periscope attack on what appeared to be an ex-Tuna boat. Three torpedoes, with a depth setting of two feet, were fired, but all missed. During the attack, which was characterized by bad weather, no damage was inflicted on the enemy by TRIGGER. The sweep terminated on orders from Commander Submarine Forces, Pacific Fleet.

4. TRIGGER resumed one naval aviation pilot while performing lifeguard duties on 12 October.

5. The events on the nights of 10 October and 31 October indicate that radar-equipped planes, working in conjunction with submarines, are employed by the enemy as an anti-submarine measure.

TRIGGER arrived at Guadalcanal in reasonably good material condition, except for her interior communication system, which appears to be overloaded. Every effort will be made to improve before she goes on another patrol. Otherwise, her refit will be normal, by SERRY and Submarine Division 101, Personnel were in good spirits and in good shape physically.

7. The Squadron Commander congratulates this Commanding Officer, the officers and men of the TRIGGER for the damage inflicted on the enemy, and welcomes them to Camp Dealey as the first guests there.

8. It is recommended that TRIGGER be credited with inflicting the following damage on the enemy:

DAUGER
1 converted tanker
14,000 tons.
(Exact tonnage not known but abeut)

Copy to:
CO TRIGGER.
G. L. RUSSELL.

— page 51 —
23 DEC 1944
FF12-10/A16-3(15)
Serial 02762
CONTINUATION
SECOND SUBMARINE REPORT to
TRIGGER report of
Tenth War Patrol.
CO. SUBPAC PTROL REPORT NO. 591
U.S.S. TRIGGER - TENTH WAR PATROL
From: The Commander Submarine Force, Pacific Fleet.
To: The Commander-in-Chief, United States Fleet.
Via: The Commander-in-Chief, U.S. Pacific Fleet.
Subject: U.S.S. TRIGGER (SS237) - Report of Tenth War Patrol.
(24 September to 3 November 1944) and (10 November to 23 November 1944).

1. The tenth war patrol of the TRIGGER was carried out in two phases. During the first phase the TRIGGER conducted its patrol off the East Coast of Formosa and among the Southern Islands of the Nansel Shoto. The TRIGGER was one of three submarines forming a coordinated attack group with the U.S.S. SILVERSTAR (SS236) and the U.S.S. SALMON (SS182). During the second phase, the TRIGGER was one of seven submarines forming an anti-patrol vessel sweep off the Bonin Islands.

2. On two occasions the TRIGGER contacted enemy task forces and, although unable to close, sent out valuable contact reports. The only contact worthy of torpedo fire that could be closed was a large enemy tanker with four escorts. The TRIGGER made an aggressive attack on this tanker and damaged it sufficiently to stop it, which enabled the SALMON to damage it further and the U.S.S. STERNET (SS 392) to sink it.

3. The TRIGGER also rescued a Naval aviator off the North Coast of Formosa during the first phase. In addition, the TRIGGER was one of the four submarines forming a protective screen around the damaged SALMON, successfully escorting her to Saipan.

4. During phase two the TRIGGER attacked patrol craft with both guns and torpedoes. The shallow draft patrol vessels and the rough seas prevented damage to the enemy.

5. A ward of the submarine Combat Insignia for this patrol is authorized.

6. The Commander Submarine Force, Pacific Fleet, congratulates the commanding officer, officers, and crew for this aggressive

— page 53 —
1. The Commander-in-Chief, United States Fleet.
To: The Commander Submarine Division ONE HUNDRED TWO.
Via: (1) The Commander Submarine Squadron TEN.
(2) The Commander Submarine Squadron TEN.
(3) The Commander Submarine Squadron TEN.
(4) The Commander-in-Chief, U.S. PACIFIC FLEET.

Subject: U.S.S. TRIGGER - Report of War Patrol Number SLEVEN.

Enclosure: (A) Subject report.
(B) Trace chart (ComSubPac only).

1. Enclosure (A), covering the ELEVENTH war patrol of this vessel, conducted in the ENIGO SUBD - KII SUBD area during the period 25 December 1944 to 3 February 1945, is forwarded herewith.

P. D. HURLBINGER, II.

FILMED
106 BKS

— page 55 —
1 January 1945

| Date       | Time         | Location          | Notes                                                                 |
|||||
| 0830      | c/o to 000°T. | Slighted plane (Plane Contact #2). Dove. |                                                                  |
| 1245      | Surfaced.     |                       |                                                                  |
| 1206      | c/o to 305°T. | On Station. Entered southeast corner of Area 8. Decided to cut across traffic lane between JUMPO SUIDO and WAI DIKEN STRAIT so as to patrol across all possible Jcp Fleet sortie lanes. Our forcoas were sailing for LINGAIEN GRIP. Fleet was striking FORDASA. Set course 300°T to close TOI MISAI. |                                                                  |
| 2100      | Submerged.   |                       |                                                                  |
| 1152      | Surfaced, c/o to 040°T. | Slighted TCI MISAI bearing 285°T, distance 50 miles. |                                                                  |
| 1645      | Slighted plane (Plane Contact #3). Submerged. |                                                                  |
| 1714      | Surfaced.     |                       | Fleeted up SFR signal on 207 mge. at Iatt. 53-57 ft, Long 133-42.5 E, and almost immediately thereafter piloted up a signal on 150 mge. (Plane Contact #4). These signals were weak and intermittent when first piloted up, but by |                                                                  |
| 1945      | c/o to 130°T to close. Contact became steadily stronger. |                                                                  |
| 1949      | c/o to 130°T to close. Contact became steadily stronger. |                                                                  |
| 1955      | SFR contact weak on 150 mge. |                                                                  |
| 2001      | Conditions the same with nothing in sight from radar or bridge, so commenced maneuvering trying to establish S.J. contact. The signal, however, rapidly decreased, so at |                                                                  |
| 2040      | took course 135°T again. Intermittent and weak signals were received until 1940. No contact was made on S.J. at any time. The only conclusion we could draw was that the Japs had turned tail on picking up our S.J. signals and made 20 knots good while we searched |                                                                  |

— page 56 —
2200 Entered Area 6B. Changed course for surface patrol of possible Jap Fleet routes from KOBE or TOKIO. This area also covered BONH-SUNGO SUDO tanker route.

: 3 January Weather gradually built up to a winter gale.

: 0722 Submerged at intersection of KII SUDO-VAN DIEMEN STRAIT, and SMNO SUDO-20MIN routes for submerged patrol to train diving officers in controlling boat in heavy sea.

: 1712 Surfaced. All sections showed progress in depth control.

: 2105 Sighted light bearing 320°T. o/o to close. At same time had a dubious momentary radar contact.

: 2135 Sighted torpedo wake pass up stab. side, 200 yds. abeam. At this time we were approximately 10 miles north of the spot where radar interference was encountered on preceding night. Reversed course to clear area. Someone had the drop on us.

: 4 January Submerged patrol - weather still very rough.

: 5 January

: 0725 Submerged 15 miles northeast as spot where we'd had troubles during the last few days and nights to investigate during daylight.

: 1130 o/o to 145°T.

: Squalls in port shaft returned to plague us remainder of patrol. Return to port was considered but decision was made to remain on station if squalls did not occur below 80 r.p.m.

: 1850 Surfaced.

Ship Contact #1
Lat. 51-42 N. Long. 135-46 E
Ferrisope

: 1709 Sighted periscope (Ship Contact #1) bearing 240°T, distance 2000 yds. - avoided on surface. Round two to the dap. We're hunted him both day and night, but have ended up being the hunted each time.

: 6 January

: 0747 Submerged. Weather made diving time 2°40".

: 1821 Surfaced. o/o to 305°T to move into area 6. Barely making five knots at s/s due to mountainous waves.

: - 3 - Enclosure (A)

— page 57 —
7 January
U.S.S. TRIGGER - Report of War Patrol Number ELEVEN (Cont'd.)

7 January
0758 Submerged 40 miles, bearing 150°T ASHIZURI SAKI, and set course 030°T to close MUROTO ZAKI.

1522 Wind and seas calmed a little so surfaced but sighted plane (Plane Contact #6) and submerged immediately. Diving time 14°C.

1546 Sighted ASHIZURI SAKI bearing 295°T, distance 30 miles.

1600 Wind increased again; mountainous seas.

1908 Surf-ocd. Patrolled KII SUINO approaches, and HUNGO-20HIN route.

8 January
0706 Submerged 16 miles, bearing 150°T from MUROTO ZAKI and patrolled western entrance to KODE.

1908 Surf-ocd. Patrolled across mouth of SUNGO SUINO. Storm was worse. It was a battle to keep control and forward engine rooms dry.

9 January
0716 Submerged with ICHIE SAKI bearing 015°T, distance 15 miles, set course to close coast. Sections seemed strained well enough. Broad-od only once during entire day. This was an excellent performance in view of the fact this was the first rough weather experienced by diving officers.

0955 Sighted plane (Plane Contact #6). Closed and patrolled 3 miles from beach on course between AHUI SAKI and Long. 135=0 E during day. A total of 7 small sailing boats were seen but no other shipping of any description.

1900 Surf-ocd.

10 January
0713 Submerged with AT-AKI SAKI bearing 030°T. Set course 035°T to close coast.

Squeals returned intermittently in both shafts at various speeds, including 1/3 speed (50 turns). It was found possible to stop the squeal for long periods by going up to full speed and stopping suddenly. Continued patrol.

1950 Surf-ocd.

11 January
0713 Submerged with ICHIE SAKI bearing 050°T, distance 14 miles, and closed to 3 miles to patrol along 100 fm. curve.

- 4 -
Enclosure (A)

— page 58 —
11 January (Cont'd.)

1125 Sighted one small coastal fishing boat rounding ICHIE SAKI and shortly thereafter sighted a PO heading toward KII SUIDO from SHIONI MISAKI. Hoping these were the advance guard of something bigger leaving KII SUIDO, changed course to 325° with ATAIKI SAKI bearing 020°T. We were on the 100 ft. curve at this time and both escorts were very close to the beach.

1200 Sighted 2 more PO boats rounding ICHIE SAKI and expected any minute to see something worth shooting at appear. Went to battle situation. Sound at this time had picked up the 3 PO boats which were on course 115°T, speed 7 knots. 2 PO's came down 100 fathom curve passing close aboard. The other remained 500 yards from beach.

Ship Contact #2
Let. 35-31N Long. 135-30E
1 small coastal freighter
3 small patrol craft

1215 Still nothing in sight from KII SUIDO and upon looking the escorts over again discovered a small coastal steamer (Ship Contact #2) had joined the trio. He had been waiting for the escorts in the river at OTAKI SAKI. We had good luck out of position by closing the escorts to the north as they rounded ICHIE SAKI. Then first seen, the steamer was bearing 080°T and heading for SHIONI MISAKI with 130(S) angle on the bow four miles to the southeast, so scoured from battle stations with hope that bigger things might start moving.

1228 Echo ranging which lasted about 5 minutes from the direction of the escorts. Had a few squalls from sniffs during the time escorts passed out beam but they paid no attention.

1900 Surfaced.

12 January

0722 Submerged 20 miles bearing 210°T from ATAKI SAKI and closed to patrol coastline. Patrolled along 100 fathom curve.

1855 Surfaced.

2300 Received ComSubPac 121091.

2400 Changed course to 040°T.

13 January

0707 Storm had abated. Submerged with SHIONI MISAKI bearing 320°T. Set course to close KINTORI ZAII. Spent the day 3 miles from the beach. One small fishing boat was sighted.

1118 Sighted plane (Plane Contact #7).

- 5 -

Enclosure (A)

— page 59 —
13 January (Cont'd.)
1914
Surfaced and commenced patrolling east and west between Latitudes 35°45' N and 35°55' N.

14 January
C590
At 34-52 N, 126-37 E, observed a weak SPR signal on 99 megs.

C055
S.J. radar contact bearing on a small object 225°T, range 2100 yards. Avoided at high speed and then continued searching vicinity. No further contact could be made on S.J. or sound.

C500
c/c to 090°T and went ahead standard on 4 main engines to gain day-light position ahead of this possible submarine contact.

C700
Submerged and patrolled north and south along 136-50 E.

C790
c/c to 090°T.

C155
Hoori distant heavy explosions. These explosions were heard 5 times during the next 1/2 hour, the explosions being in groups of 4 to 8. Believed they might have been "embarrassing charges" slightly out of a convoy from MOOTAH.

C160
When just having finished a periscope look at 50°, a burst of sharp explosions sounding like 20NM or 37NM shells was heard directly overhead. We had been straf'd by a plane coming out of the sun, but deep and c/o to 100°T while waiting for the bomb that didn't come (flame Contact #8).

C192
Surfaced and made retiring search along convoy lanes from MOOTAH.

15 January
C065
Sighted light about 10 degrees high moving fast (Plane Contact #9). It did not close. Received first word of 5-29 raid on MOOTAH and that no strikers were down. Discontinued search as explosions must have been "near misses". Left life guard station and headed for area.

C716
Submerged. Due to rough seas patrolled submerged.

C844
Surfaced. Seas still very rough necessitating heading into them at 2/3 speed making good about 4 knots.

C2340
SPI contact on 55 megs. This contact was very strong and consisted of a series of about 6 dots which were saturation pips on the oscilloscope. Searched the vicinity. Nothing could be found, however.

- 6 -

Enclosure (A)

— page 60 —
16 January
0731 Surrounded - weather still too rough for surface patrol. Entered area 6A.

1523 Surrounded. c/o to 300°T and headed into seas at 2/3 speed. Patrol rolled junction of all routes to NANSEI SHOTO and BONIN group.

17 January
Surface patrol in southeast part of area 6A.

18 January
Surface patrol westward in southern part of area 6A enroute next area assigned.

19 January
OBC Entered area 8. Conducted surface patrol in southeast part of area.

1315 Shifted plane (Plane Contact #10) distance 15 miles. Sky heavily overcast, did not dive. Last sight of plane in clouds.

1330 Strong SSR contact on 147 meters - submerged, as plane had apparently sighted us and climbed into clouds.

1315 Surface. c/o to 270°T to close land.

2130 Radar contact on YAMA SHIMA, distance 43 miles, bearing 295°T.

20 January
Patrolling Latitude 30°N, south of TANEGA SHIMA and YAMA SHIMA.

1019 Deck SSR contact on 147 meters. Sighted plane (Plane Contact #11). Submerged.

1048 Surface on course 060°T.

1049 Received ComSubPac 191557. It was impossible for us to catch either ship sighted by I-29's, but headed in that direction in the event more night came through.

1100 Strong SSR contact on 147 meters. Sighted plane (Plane Contact #12) 8 miles, elevation 30°. Submerged.

1655 Surface.

21 January
0023 Received word of carrier strikes on NANSEI SHOTO group. Headed for position to guard COLBERT and VINCENTES STRAITS.

- 7 - Enclosure (A)

— page 61 —
21 January (Cont'd.)
1118    Sighted plane (Plane Contact #13). Dove.
1314    Surfaced.

22 January
0738    Submerged. Patrolled on 100 fathom curve remainder of day.
1120    Sighted plane close (Plane Contact #14). Avoided.
1924    Surfaced on course 090°T. Patrolled BUNGO SUID-KOBE routes to
    NANSEI SHOTO group.

23 January
0755-    Contact on SFR (Plane Contact #15) aircraft frequency. Contact
    became stronger. Jet shifted to keying, when pulse was saturated
    at strength three, and with too many plane lockers, at
    Dove.
    U809    Surfaced.
    G922    Strong SFR signals on 150 meg. (Plane Contact #15). Dove.
   1400    While preparing to surface, discovered SD out of commission.
   1612    Sighted a Betty (Plane Contact #17) at 3000 yards, elevation
    "Angels" one, angle on bow zero. Avoided. Scoured attempts to
    surface; we were spotted in too well.
   1307    Surfaced. Set course to close TOI MISAKI at VAN DIEMEN STRAIT.

24 January
0230    Strong SFR contacts on 155 and 157 meg. from TOI MISAKI, dis-
    tance 42 miles. At 28 miles, Jap radar caused sweeping and centered
    on.
0315    Sighted single flashing red light on TOI MISAKI, single flash
    every 75'. Having approached from south searched to north for a
    possible expected convoy. Closed OSHIMA ISLAND just north of TOI
    MISAKI.
0718    Submerged 19 miles bearing 070°T from OSHIMA. Set court to close
    beach. Patrolled along 100 fathoms curve during day.
1914    Surfaced on course 145°T with weak SFR signal from TOI MISAKI.

-6-    Enclosure (A)

— page 62 —
24 January (Cont'd.)
1924
SPR contact on 208 mesgs. followed immediately by a contact on 200
mesgs. These contacts were both fairly strong when first picked up
and were very intermittent. Commented maneuvering using SFR screen
to determine approximate bearings. True bearing was determined to
be roughly 200°T.

2000
c/o to 230°T to close, but signal began to decrease in strength,
so at

2010
c/o to 145°T and signal increased in strength.

2017
Rude another check with SFR screen, and true bearing was 260°T
approximately.

2022
With 4 engines on and a 40 knot wind blowing, the navigator
heard a plane (Plane contact #18) and it was then sighted passing
overhead from port to starboard at an altitude of approximately
1000 ft. No action was taken on his part or ours and he soon dis-
appeared from sight headed for TOI NISAKI. He had no running lights
and no plane radar had been picked up since surfacing.

2030
c/o to 230°T with same results as before - SFR signal strength
decreased.

2040
Again c/o to 145°T, but signal became weaker and weaker and was
lost altogether at about 2000.

2102
c/o to 230°T, and at

2120
both signals were picked up for several minutes fairly strong with
int-rmittant sweeps. This was the last contact. The conclusion
reached after recapitulating is that at least 2 radar equipped
ships were picked up at 1824 probably in the vicinity of TOSAKI
ENAI. Travelling southward at about 15 knots. These ships rounded
TOI NISAKI about 2030 and passed through VAM DIEMEN STRATIS. The
fact that the signal strength decreased when we headed on 230°T was
probably due to his approaching our antenna "null" section. This
conclusion was reached at about 7.

2330
and we c/o to 145°T knowing, if he had gone into VAM DIEMEN STRATIS,
he was gone for good, and if our assumptions were wrong he would be
to the south east and we might regain contact. A convenient means
of making SFR directional would be a big assist.

25 January
Conducted surface patrol in south east part of area.

1230
Sighted 2 planes (Plane Contact #19). Dove.

1425
Surfaced.

1452
Sighted plane (Plane Contact #20). Dove.

- 9 - Enclosure (A)

— page 63 —
25 January (Cont'd.)
1840 Surfaced.
1958 Sighted plane (Plane Contact #21) distance 1 mile. Dove.
2018 Surfaced.

26 January
0711 Submerged at Latitude 32°N, 11 miles from the beach and patrolled along 100 fathom curve during day.
1925 Surfaced 18 miles from beach.
2100 Sighted running lights of plane, distance 4 miles (Plane Contact (22). Dove.
2135 Surfaced.
2200 Received ComSubPac 260936.

27 January
0702 Submerged and patrolled SUNO SUDO-BONIN route during day, just southwest of ASHIZURI SAKI.
1617 Sighted plane (Plane Contact #23).
1923 Surfaced.

28 January
0740 Submerged south of ASHIZURI SAKI on JUNGO SUDO-BONIN route.
1922 Surfaced in northeast's nest on course 260°T, and immediately began picking up strong SR contact on 4 different frequencies between 126 and 152 megas.
1953 Sighted first of innumerable plane-equipped radar (Plane Contact #24). The moon was full, clearest 60°, sea glassy, and clouds were scattered. It seemed bright as day during the entire night, however. The first batch of planes were easily seen from the bridge at 16,000 yards, and appeared from the north, disappearing on 000°T.
1943 Received strong signal on 200 megas., and almost immediately a second signal on 201 megas. These were definitely 2 distinct radar sets. Corrconed maneuvering attempting to locate approximate bearing, but this time our radar screen was of absolutely no assistance. Planes were in sight from the bridge continuously during this time and were being picked up easily by the S.J. radar.

-10-
Enclosure (A)

— page 64 —
28 January (Cont'd.)

2069 A Betty made a "run" down the port side and dropped 3 flares at 4 miles. Submerged diving time 52".

2012 JK sound gear picked up weak echo ranging bearing 160°T. This was simultaneously reported by JP.

2015 With a light cloud obscuring the moon, surfaced and o/c to 150°T. Only 5 planes in sight. Moon came out brightly.

2019 S.J. picked up plane at 5400 yards closing and it was sighted from bridge crossing nation. When 200 yards astern he sighted our wake and turned and challenged with a green light. Dove, diving time 42". Plane dropped 6 flares.

2030 Surfaced when a cloud covering the moon.

2042 Contact on 200 nets very strong, saturation plp with half gain, and steady on. Planes were very numerous, there being as many as 6 in sight at once, crashing ahead and astern. Parachute flares were hanging near at 045, 225, and 355°T.

2110 Plane was sighted on starboard bow, distance 1000 yds. He crossed our bow and while passing down port side challenged us with red light using "Au!". Dove. Diving time; 32".

2151 While trying to surface, S.J. picked up plane at 3200 yards crossing astern. Lights of 2 gopher planes soon thru periscope at about 4 miles. Flares had been moved closer to us on the last surface run and several of the planes had turned off running lights. Planes in pairs were working together now. One with running lights would make a run about, drop flares silhouetting us, while the second plane without lights would make a run from our other boat. Then a plane made a bad run we would stay on the surface, if the range and bearing showed a good run, we dove.

2214 With a light cloud obscuring the moon and a darker one promising, surfaced with a bubble in safety and bow buoyancy. After an all day dive and with one air compressor out of commission, we were getting seriously on air and juice. However, on the other hand, we were losing the convoy by continually boring in despite the plares; furthermore, by remaining submerged, we were in danger of being holed down at the next day's meeting. We could see clearly that fresh planes were arriving from KYUHI to relieve planes in station every hour. Year types of planes were now on hand: Betty's, Rufe's, Jake's, and Zeke's. We were tracking the larger planes on the S.J. out to 23,000 yards.

2226 Strongest signal on 201 meg, yet received. We were clearly gaining! Signals were now being received from 2 sets on 200 meg, one on 201 and one on 209.

-11- Enclosure (A)

— page 65 —
28 January (Cont'd)
2240
Gearing on flares now, true bearing had decreased on 080°T from 100°T. Planes had been in constant attendance, but in the dark of the cloud they had fallen aft in their runs. We zigged from dark spot to dark spot as best we could while closing rough bearing of convoy.

2312
Moon came out bright again.

2314
Darkened Rufe spotted us and headed in fast flashing his landing lights(7). Dove. Diving time to 60' almost negligible.

2322
Had gained on now flares until bearing was 052°T.

2334
Flares were now bearing 032°T. We had been running at 42' tracking planes with S.J. Their searches or runs were close, some passing right overhead, but no bombs were dropped. Why, we'll never know.

2359
c/c to 210°T on picking up weak echo ranging on that bearing.

29 January
2222
Planes were all now searching aft again, closest runs being about 5000 yards away, so with echo ranging weaker and a cloud starting across the moon, surfaced.

SHIP CONTACT #5
LAT. 31-11 N. LONG. 132-48 E.
LARGE CONVOY

0236
Radar contact 13,000 yards bearing 230°T. This was seen from bridge to be another bomber crossing from stab. to port. Smoke sighted from four to six ships running 23,000 yards. on same bearing 160°T, radar range 23,000 yards.

0244
Lady Luck turned her face and the moon came out bright and clear. The number previously mentioned, which had been flying a 20 mile box around the convoy, spotted us and headed in. Simultaneously, the S.J. picked up a second plane coming up from astern at 5000 yards. Our wake with four engines on looked four miles long in the bright moonlight, so with the bomber giving "AA, AA", dove. This was heartbreaking to be sighted again after successfully breaking out of the encirclement and after having established sight contact on the convoy.

0251
Escorts again started echo ranging, five sets of echo rangers were picked up true bearings 165 thru 210°T. One escort was tracked leaving the convoy and heading back in our general direction; he passed about six miles west and then started searching. The convoy's sounds (sorews and pings) gradually got weaker, fading on 180°T. Planes had started their circuits overhead again. We alternated between 421 and 60' watching the show and gradually drawing away to the south.

- 12 - Enclosure (A)

— page 66 —
29 January (Cont'd.)

0400 A favorable opportunity to surface presented itself, moon hidden momentarily and closest plane 3 miles. On passing 35 feet, the plane that was closest apparently gained radar contact and closed. He passed overhead as we struggled back down. Attempts almost identical in nature to surface met with no success until about 0530. After waiting 30 minutes for bomber ahead to finish his "stern" leg of convoy, at

0609 Surf.ced with SFR-SFA, SD, SJ, and our 1 air compressor running, and charging with 3000 amp hr. rate. Determined to dive on any plane contact to avoid being sighted during daylight, as our only chance was quick surfacing and chasing. Convoy was 38 miles ahead on course 180°T., speed about 8 knots.

0740 Sighted plane at 10 miles (S.J., range). (Plane Contact #25). Dove.

0902 Plane still in sight searching around at range of 2 to 3 miles.

0920 All clear, surfaced. The plane had gone off to the convoy.

1107 Sighted Betty (Plane Contact #26) coming back on stern leg again, and almost immediately a float type Zero which had gotten in to five miles undetected by S.J. Dove.

1250 Appeared all clear. Planes had neared around a few minutes, then shoved off. Surfaced.

1357 Sighted 2 Betty's (Plane Contact #27). Dove. These stayed in the vicinity much longer than usual, afreid we had been sighted.

1555 No planes having been in sight for 30 minutes, surf.ced. Out in engines on propulsion as fast as they came off charge until we were making 19 knots. Last planes had disappeared to southwest instead of south, but at

1700 sighted a new empty packing box, so decided to search first to scutt, then running a search curve to south west.

2130 c/o to 255°T, with wind and sea building up rapidly from 045°T.

2200 Finally cleared TRIGGER 1st to ComSubPac and Kuru Morque giving all available information on convoy. All attempts to get DEWIPISH and Kuru Morque on ...P. frequency had failed.

30 January

0630 Completed search to south and southwest. Convoy had either cut inside NMSEI SHOTO group or gone to RONIN's. Leaving western search to Kuru Morque, headed east for RONIN search route.

0700 Weather stepped in and slowed us to 2/3 speed on 1 main engine.

- 13 - Enclosure (a)

— page 67 —
30 January (Cont'd.)

2200 Received ComSubFle's 301021 terminating patrol, weather having previously made further search ineffective. o/c to head for "Funnel" making 5 knots into mountainous seas.

31 January

0942 Wind and seas diminishing rapidly, went to s/s on 1 main engine.

0949 o/c to 150°T.

1 February

0250 Exchanged recognition signals with U.S.S. SUNFISH.

0355 o/c to 140°T.

1225 Sighted plane (Plane Contact #20). Exchanged recognition signals with PB4Y.

2 February

0118 o/c to 130°T. Entered western end of "Funnel".

2053 Heard loud crackling in cubical and lost power on port shaft. Flames and sparks were seen behind cubical. Could not get power to port main motor fields. All stop on port shaft. Simultaneously, water was discovered above deck plates in motor room and smoke was seen to issue from #2 main motor. Examination found both reduction gear sumps containing salt water. Source of water not yet determined. A complete report will be submitted under separate correspondence.

2100 All stopped. Isolated #2 main motor fields and armature.

3 February

0100 Underway making 160 turns port shaft, 230 turns stbd. shaft.

0150 Cleared TRIGGER third message to CTG 17.7

1502 Moored port side to starboard side of U.S.S. AFOLIO in Port Apra Harbor, Guam, Marianas Islands.

- 14 -

Enclosure (A)

— page 70 —
1-1-45 1-1-45 1-1-45 1-1-45 1-1-20-45 1-1-20-45 1-21-45 1-21-45 1-22-45
Date: 1650 2425 1215 1019 1100 1118 9765
Time (Zone): (-10) (-10) (-10) (-10) (-10) (-10) (-10) (-10)
Position: Lst. 33-41 N 33-22 N 30-19 N 30-00 N

— page 71 —
15 16 17 18 19 20 21
Date: 1-23-45 1-23-45 1-23-45 1-24-45 1-25-45 1-25-45 1-25-45
Time (Zone): 1:12 1:12 1:12 1:12 1:12 1:12 1:12 1:12
Position: Lt. 35-27 N 30-49 N 30-50 N 31-30 N 34-48 N 35-50 N 51-09 N
Length: 132-25 E132-29 E132-43 E132-10 #132-55 E132-50 E132-41E
Speed: 11 11 2.5 14 11.5 11 10
Course: 140 120 120 145 330 330 340
Trim: Sur. Sur. Por. Sur. Sur. Sur. Sur. Sur.
Minutes since Last: * 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
SS Radar Search: "0.00" "0.00" "0.00" "0.00" "0.00" "0.00" "0.00" "0.00"
* "0.00" Indicates Radar not in use.

Number | Unk. | Unk. | Lt. | Lt |

— page 72 —
22 23 24 # 25 26 27 28
Date : 1-28-45 1-27-45 1-28-45 1-29-45 1-29-45 1-29-45 1-29-45 1-29-45
: 2100 : 1617 : 1939 : 0740 : 1107 : 1357 : 1226 :
S Time (Zone) : (-10) : (-12) : (-10) : (-10) : (-10) : (-10) : (-10) : (-10) :
Position: Lat. : 31-56 N 132-05 M 131-30 N 130-32 N 129-57 N 123-10 N :
: 132-25 E 133-08 E 132-40 E 132-50 E 132-50 E 132-50 E 132-50 E 132-50 E :
Speed : 11 : 2.5 : 12 : 14.5 : 17 : 17 : 17 :
Course : 110 : 20C : 20C : 18C : 19C : 19C : 19C : 19C :
Trin : Sur. : Per. : Sur. : Sur. : Sur. : Sur. : Sur. : Sur. :
Minutes Slice Last : "

— page 74 —
35.1 TRIGGER - Report of War Patrol Number ELEVEN (Cont'd.)

(a) RUDAR:

S.J. Radar performance was very good throughout patrol. Ranges on land (2200 ft. elevation) up to 65,000 yds. were obtained, planes at 16,000 yds. Time out of commission for repairs totalled about four hours. No unusual jarring or interference was encountered. Gear was used intermittently close to land. Japs apparently are using directional search receivers covering S.J. frequency.

S.D. was operated very little during patrol and when used was operated intermittently. No jarring or interference (other than SFR at 65-20 megacycles) was encountered.

SPR-SFA was used continuously throughout the patrol and continued to serve as an excellent early warning device. Efforts to determine rough bearings of surface ships' radar be means of a shielded proved partially successful and warrants further development.

On night of 28 January (sea narrative for our hide-and-seek game with radar planes and ships) during presence of two very strong signals at 200 megacycles, two changes in pulse rate were noted from one signal source, obviously a deliberate signal from the Japs operator. About 30 seconds later both radar sets were caught off and were obtained only once again 5 minutes later. Spare unusual signal shapes were encountered during this process and are sketched below. Japs planes were also using some form of lope switching as evidenced by double traces at top of plot.

Frequancy - 167 n.c.
P.R.P. - 1250; F.R. - 8 u.s.

Frequancy - 201 n.c.
F.R.P. - 1100; F.R. - 18 u.s.

Efforts to use the shield to give rough bearings proved of no value during events the night of 28 January. This may have been due to presence of at least three different sources of 200 megacycle radars which interfered with bearing readings.

- 21 -

Enclosure (i)

— page 75 —
1. Erratic sweep intensity and splotches on PFI. Replaced R44. (R44 spares are almost impossible to obtain - we were lucky, we had one spare).
2. Blown fusos, no pilot light. When fusos renewed and high voltage switch thrown on, excessive rectifier current drawn and blow fusos again. Found time delay relay had stuck closed. Temporarily bypassed it adjusting ii.v. Variance to allow tubes to warm up. Later disassembled, cleaned and replaced time delay switch.
3. No sweeps on range indicator on PFI. Found open Synch cable. Resoldered both tips.
4. Regulated rectifier voltage drifting badly. Renewed 6YG tubes, some of which had only about 100 hrs. on them. Also renewed VR-150 and VR-105 tubes, A week or so later we experienced another similar trouble - - -
5. Fuse #8 blew. Trouble traced to shorted 6YG tube in "A" rectifier. Also found both "E" rectifier 5UG15 had as a result of this - one shorted, one burned out. Probably would be advisable to renew all four 6YG tubes in a unit when one goes bad.
6. Renewed several tubes showing low emission when tested.

S.F.R. TROUBLES

1. A wildly erratic pattern on screen, appeared due to faulty pulsing. After much checking and double checking, an intermittent was found in a cable between T105 and R109. A temporary jumper was installed and all was hunky-dory - seven hours later.

S.F.R. TROUBLES

1. An exasperating trouble caused intermittent output of receiver. A damaged banana plug was repaired, a loose fuse holder secured without results. Finally found resistor, R201, cracked and evidently intermittently open. Renewed resistor and trouble cleared.

S.F.R. CONTACTS

| Pre- | Pulse | Pulse | Date | Position | Remarks |
|------|-------|-------|-------|||
| 73*  | 27    | 500  | 090230 | 13-35 E  | Weak signal. Strayed on |
| 73 * | 27    | 500  | 090230 | 13-35 E  | Fuse still de- |
| 73 * | 27    | 500  | 090230 | 13-35 E  | weak signal. |

Enclosure (A)

— page 78 —
31-08 N : 1
157 * : 7-8 : 6'60 : 2321200 : 132-09 E : Notating Antenna, weak signal.
: 31-28 N : 1
168 * : 7-8 : 600 : 241930 : 131-56 E : Easily strong, rotating antenna.
: 30-55 N : 1
200 @ : 6 : 1 : 021450 : 132-15 E : Two signals present. Weak.
: 31-46 N : 1
208 @ : 16 : 1000 : 021940 : 132-42 E : Signal strong and steady. Chased.
: 31-30 N : 1
208 @ : 10 : 1250 : 241937 : 132-08 E : Strong signal. Chased
: 31-30 N : 1
200 @ : 10 : 241940 : 132-08 E : Precast at some time as above,
: 31-30 N : 1
200 @ : 12 : 1150 : 261343 : 31-19 N : 1
201 @ : 7-8 : 125 : 232226 : 132-42 E : 1
: 31-30 N : 1
208 @ : 12-10 : 1000 : 28214 : 1000 :

— page 81 —
1. The Commander Submarine Division T.O. MIGHTY OS
To: The Commander-in-Chief, United States Fleet.
Via: (1) The Commander submarine Squadron Task Force.
(2) The Commander Submarine Force, NAVY FLAG.
(3) The Commander in Chief, U. S. PATROL FLAG.

Subject: U.S.S. TITAN (SS-237) - Report of USS MIGHTY OS

1. The eleventh war patrol of the TITAN was conducted in waters east of HINDOO and HII ISLAND, while the overall length of the patrol, thirty-eight days, was less than average the first half of the month and the last half of the month. The patrol was characterized by foul weather, plentiful enemy air activity, and dispassionately few ship contacts.

2. The period of four days commenced 2 February and in the same general locality, about seventy miles south of NIGHTMARE, HINDOO encountered first six small apparently oncoming from submarine equipment but was unable to locate the carrier, avoided a torpedo and sighted a periscope (38 ft.). Apparently the enemy continued to use his submarine as anti-submarine craft.

3. The tension development of the OP contact at the evening of 2 January and the subsequent change, both conducted in the face of extremely heavy if improbable pressure, air opposition, extremely severe weather, and the threat that the fleet might be attacked by a large escorted convoy a more than 100 percent chance to strike. It is noted that the submarine's difficulty was encountered in descending the contact report.

4. With the exception of the badly damaged main motors (usually described in narrative under item 2.2 below but not marked in section F) MIGHTY returned from patrol in very good material condition, clean and ship shape. It is estimated that the fleet will require three weeks, repairs to the main motor being the controlling factor.

5. The Division Commander extends his sympathy on a difficult patrol during which, and despite morale effort, it was impossible to engage the enemy. It is his confident prediction, based on the spirit shown by the entire ship, to carry, that there will be better luck next time.

L. H. CHAPMAN

— page 83 —
2-10(A)/L15-3(1G)  SUBMARINE FORCE, PACIFIC FLEET
Serial 0312
CERTIFICATE
THIS REPORT WILL BE
DISTRIBUTED PRIOR TO
ENTERING CONTROL.

From: The Commander Submarine Force, Pacific Fleet.
To: The Commander-in-Chief, United States Fleet.
Via: The Commander-in-Chief, U.S. Pacific Fleet.

Subject: U.S.S. THRIGGER (SS237) - Report of Eleventh Patrol (26 December, 1944, to 3 February, 1945).

1. The eleventh patrol of the THRIGGER, under the command of Commander F. J. Kerrington, II, U.S. Navy, was conducted in the Bungo Suido - Kii Suido area.

2. Despite thorough and aggressive area coverage, few contacts were made with the enemy. Air and radar anti-submarine measures were barely throughout the patrol and thwarted the THRIGGER's attempts to close a large convoy contacted on 29 January. Evidence of continued use of submarines as an anti-submarine weapon by the enemy was encountered in the form of a torpedo wake and prismsights in the area.

3. ...ward of Submarine Combat Insignia for this patrol is not authorized.

J. H. HONN, Jr.,
Deputy Combat Submarine.

DISTRIBUTION:
(Complete Reports)
(Continued)
CINCPAC
JICPC
LACPC
Conscwrpc
Cincalant
Consubelant
S/Si School, NL
CO, S/F/Basc, PH
Consopac
Consowscpac
Consubswscpac
CTFC 71.9
Comorpac
Consubspac
Consubspac.d
SUB.D, II
ConsubspacSubordcom
(7)
(5)
(6)
(1)
(1)
(1)
(8)
(8)
(2)
(1)
(2)
(1

— page 84 —
1. TRIGGER (SS 237)
2. Departing Guam on 11 March 1945, TRIGGER, under the command of Cdr. D. R. Comole, headed for the Nansei Shoto area to conduct her twelfth war patrol. She was to provide rescue services for carrier based aircraft, as well as to carry out a normal offensive patrol.

After having sent several routine messages enroute to her area, TRIGGER reported her first action on 18 March. She stated that she had made a seven-hour end around on a convoy she had previously reported, and had attacked. She sank one freighter and damaged another. The other two merchantmen of the convoy and four escorts proceeded west.

For some time, Allied forces had been aware of a large Japanese restricted area west of the Nansei Shoto in the East China Sea. The area had been marked "restricted" in captured enemy notices to mariners, and Allied forces were obliged to accept that the area was mined, and to keep out of it. Submarines had been warned of its presence and given its position, and were in the habit of proceeding around it to the north when patrolling the Japanese Strait and the adjacent China Coast. The convoy which had been attacked by TRIGGER was heading for this restricted area. It had always been strongly suspected that there were gaps in the minefields, since the area was too big to be at once completely and effectively mined.

Immediately after receipt of TRIGGER's report of the attack she had made, ComSopPac told her to give as much information as possible concerning the subsequent movements of the convoy, in order to help establish the existence of a safe passage through the restricted area. On 20 March TRIGGER reported that the attack

— page 85 —
20-44E, and that she had been held down for three hours by escorts following the attack. When last seen hours