AREA: North of latitude 7d - 15 and SW of a
line bering 315dT from TAUARAR Pass.
OPERATION ORDER: Number 73-42.
1. NARRATIVE.
August 23- 0900 (VW) Departed Pearl.
Made trim drive and
received two indoctrinational depth charges from
escort. Set speed 14 knots for area.
August 26- 0630 (X) made trim drive
August 26- 2230(Y) Crossed 180th Meridian.
August 28- 0700(M) Lookout reported sighting
airplane.
Unconfirmed. Improbable.
August 29- 0720(M) Submerged. Surfaced at 1730.
August 29- 1830(M) Aircraft contact on Radar
at ten miles.
Sky heavily overcast and squally. Submerged.
Surfaced at 1900. Position ninety miles East of
TAONGI TOLL.
August 31- 0625(L) Sighted airplane about
six miles ahead.
Submerged. Surfaced at 1730(L).
September 1- 0600(L) Aircraft contact on Radar at three
miles.
Submerged. The time of day and geographical
position (North of PONAPE) made this contact most
unexpected. However there was a very bright moon
and possibly this area is being given a thorough
search. During the night O.O.D. had picked up
three greenish lights at about half hour intervals
in the distance. There maybe a connection between
the lights and the early morning contact.
September 1- Sound contact ahead. Nothing in sight
by
periscope. Sound followed contact 30d change in
bearing and reported propeller beats and speed
changes. Lost contact after about twenty minutes.
(0720(L).
September 3- 0500(K) Commenced periscope patrol.
Submerged
outside of assigned area between HALL and
NAMONUITO Islands about 40 miles NE of boundary
line, proceeding southwesterly.
September 4- 2300(Y) Sighted TOL Island bering
090T distance
about 30 miles.
September 5- 0430(K) Picked up fast propellers which
crossed
the bow heading for TRUK. With a bright moon and
glassy sea nothing was sighted, so it was presumed
to be a small patrol boat.
September 6- 0525(K) Sighted a loaded ship similar
to WYOGO
MARU class tanker, S77, except there was only one
stack. Approached and fired three torpedoes at
range of 1430 yards (using 50ft. masthead height).
Position 15 miles off TRUK. Target headed for
PIAANU PASS. Observed airplane on far side of
target at about three miles just before firing.
Observed target for about one and on half minutes
after firing, and saw torpedoes leading her track.
About 1 1/2 minutes after firing she started a
turn toward us. Assured the torpedoes had all
missed or run under so turned toward and went
deeper to run under target. At approximately 2
minutes, 20 seconds after first shot one explosion
was heard followed shortly thereafter by a second
explosion. Lost sound of propellers shortly after
explosions. From the timing it would appear that
the actual firing range was about 3000 yards and
that at least one and probably two torpedoes were
detonated by the target or its wake. Because of
sea conditions, proximity of the base, and the
presence of an airplane screen no periscope
observations were made after the explosions.
There is no visual evidence to warrant claim of
damage to the enemy.
September 8- 0748(K) Sighted reconnaissance Bomber
type 95 at
about two miles distance.
September 10- 0612(K) Heard distant underwater explosion,
followed by others at 0620, 0634, 0644, and 0653.
September 10- 1345(K) Heard five (5) distant underwater
explosion at about ten (10) seconds apart.
September 11- 0010(K) Picked up propellers bearing NORTH,
and
lost sound contact about ten minutes later on NW
bearing. Nothing sighted. Presumed it was a
small patrol boat passing fairly close aboard.
September 13- 0452(K) Heard two (2) underwater explosions
about
ten (10) seconds apart followed by two (2) more at
0455. Estimated distance of 8 to 10 miles.
September 14- 1025(K) Picked up propeller noises, and
shortly
thereafter sighted ship bearing 270dT, distance
12,000 yards, angle on the bow 65d port. Ship was
screened by a single float plane similar to Navy
Reconnaissance Bomber type 95, and by a small
patrol boat. Came to normal approach course and
approached by sound for thirty two minutes. At
the end of thirty two minutes came to periscope
depth for the shot and found range to be 4,000
yards and track about 110 port. Target was
identified as a small freighter of about 2500
tons, and being in an unfavorable firing position
broke off the attack. Ship proceeded into TRUK
via PIAANU PASS.
The surface escort was not observed through the
periscope, but was plainly heard and tracked by
our sound. It was the same high pitched, fast
propeller beat as was heard on the 5th and 11th of
Sept. The escort would run for about five minutes
and get ahead of the freighter, then lie to and
drop astern. It was presumed that the had
listening gear but no echo ranging. There was no
indication that we were detected, which is further
born out by the fact that our target made a 25d
zig in our direction during our approach.
September 14- 2055(K) While engaged in routine servicing
of
torpedoes No.1 tube as [sic] inadvertently fired
with a fully ready war shot in the tube, both
outer and inner doors being closed, and with 400
lbs., per square inch, of impulse air. Details
are given under "Major Defects Experienced." This
tube is out of commission for the remainder of the
patrol.
September 20- Having spent seventeen days in Southeastern
part
of the area and seeing but two small ships heading
toward PIAANU PASS, decided to spend a week
patrolling south of NAMONUITO Island for East-West
Traffic.
September 20- 2255(K) With a bright moon, clear sky,
no wind,
and a flat sea, the O.O.D. sighted a column of
smoke bearing 322dT. Ran toward it for half an
hour on the surface and then submerged for a
periscope attack. At 0001 target was identified
as a freighter of about 6500 tons of the KEIYO
MARU Class, similar to that of plate 69. Course
estimated at 135dT. Speed 12 knots at this time,
although at various times the ship would stop and
lie to for appreciable periods.
September 20- It was later discovered that we were at her
rendezvous point with an escort. At 0005 it was
seen that our tracks were very close together and
we swung left for a stern tube shot on the
starboard track. Target passed abeam about 200
yards distance and at 0008 we fired the first
torpedo on 140 starboard track. This torpedo
undoubtedly failed to arm. The second torpedo was
fired with a 2d right spread on 155 starboard
track. It apparently ran down the starboard side
of the target and target saw it and turned left.
Third torpedo was fired with a 2d left spread on
162 starboard track and also missed. By this time
target presented a 90d port angle on the bow, and
with a fourth new setup on TDC another torpedo was
fired on 108 port track. This torpedo hit the
target 1 minute and twenty seconds after being
fired. Target took a port list of about 50d and
settled bodily and by the stern, as witnessed by
four or five observers, and her engines slowed
radically. Four minutes later there started three
series of underwater explosions, each series
consisting of three or four explosions, and when
upon observation through the periscope we first
sighted the escort arriving on the scene. He
dropped perhaps a dozen depth charges, none within
a thousand yards of us.
At about 0030 there was considerable confusion
around the target. Accompanied by sounds believed
to be internal explosions, a billow of heavy black
smoke came off the target, and it was no longer
seen or heard. By this time we were about 4000
yards away so we surfaced to clear the area.
About the time we got to 21 knots the escort
picked us up and with a tremendous stream of black
smoke pouring out of his stack he gave us chase.
He was closing the range by leaps and bounds when
along came the most welcome rain squall that it
has been our pleasure to encounter. We passed
into the squall and made a radical course change.
When we came out the other side we found that the
escort had followed us through so we eased back
into the rain and went the other way. When next
we got into the clear the escort was barely
visible on the horizon and he did not pick us up
again.
There is no doubt in the minds of any of this crew
but that we sunk the freighter.
September 24- 2200(K) Sighted patrol boat bearing 090dT.,
distance 5 miles, angle on the bow zero. Moon
bright, sea calm, visibility good. Submerged.
Patrol passed about 3000 yards astern, heading
West. Surfaced at 2330 and remained in area so
see if he would return escorting a target. Such
was not the case.
September 25- 0415(K) On routine daylight dive there
was some
trouble in getting the ship down. Upon surfacing
at night found that the Bow Buoyancy vents were
not operating properly. Removed bow buoyancy
manhole cover for remainder of patrol.
September 30- 0520(K) Sighted ship later identified
as Aircraft
Tender CHIYODA bearing 322dT., course 170dT, range
12,000 yards. Estimated target was headed for
PIAANU PASS and that we were in ideal attack
position. Two minutes later target zigged 40d
left. Three minutes after this zig he went 35d
further left. We turned to normal approach course
and closed the range to 6,000 yards, at which
point we were on 130d starboard track. Target
then made another left zig presenting 175
starboard angle on the bow and went over the hill
on course 075dT., heading apparently for NORTH
PASS in to TRUK. Weather was ideal for submarine
approach and we were able to watch target
continuously except when making high speeds to
close the range. There were no screens or
escorts, and any planes might have been overhead
never came within the periscope field. the Japs
were just begging someone to knock off this
Tender, but it was not our lucky day. In 24
minutes he zigged 95d away from us.
September 30- 0745(K) Sighted airplane to Northward
flying
EAST.
0850(K) Sighted airplane to Northward flying
EAST.
October 1- 0700(K) Sighted airplane
to Northward flying
EAST.
October 1- 1412(K) Sighted smoke bearing
220dT. Smoke in
sight for two hours. By plot we estimate it to
have been a ship on Easterly course, speed 10 to
15 knots, Minimum distance to our track 18 miles.
October 1- From what we have seen and heard
it is believed
that a great portion of the shipping from the
Empire to TRUK is running close to NAMONUITO, with
medium and large ships entering NORTH PASS. We
cannot patrol pass between NAMONUITO and EAST FAYU
so, having but a few days left, decided to patrol
for ships making a landfall on ULUL. This lane is
not in any assigned submarine area. It is
believed that the spirit of our orders will permit
the stretching of our Western patrol limit to
Longitude 149dE., especially if events turn out to
favor us with a target or to discover a main
shipping lane.
October 3- 1350(K) Sighted ULUL Island,
NAMONUITO, Bearing
035dT., distance 9 miles.
October 3- 1535(K) Sighted fishing
boat bearing 122dT., on
course 320dT., distance 6,000 yards. Boat passed
1,000 yards abeam and continued on to North West.
While watching it sighted masts of a similar boat
to Northward. We were at this time about 8 miles
West of ULUL Island. First boat was in sight
about an hour, the second was only seen once.
October 4- 1920(K) Sighted lights
of a small craft bearing
220dT., and lost them 20 minutes later on bearing
244dT. Estimate it to have been a fishing boat
similar to one seen on October 3, on course NW.,
and passing about 4 miles South of our track.
There were two white lights in a horizontal line
about 50 feet apart, and periodically a red
flashing light showed between and below the white
lights. We were on the ships starboard beam, so
it was not a side light. Believe it to be a
station ship for incoming traffic. Remained in
position, lying to awaiting return of small craft
in company with suitable target.
October 5- 0400(K) Received Comsubpac
despatch assigning us
to Southern Sector of area in addition to sector
already assigned. Started South and East to head
for new sector.
October 5- 0654(K) Sighted aircraft
carrier RYUJO
accompanied by two AMAGIRI class destroyers
bearing 220dT. angle on the bow 60d starboard,
range 11,000 yards, speed 14 knots. One DD was
leading and second was trailing carrier. Made
approach which, upon final analysis, lacked
aggressiveness and skill, and closed range to
about 7,000 yards. Watched the best target we
could ever hope to find go over the hill untouched
at 0800. A normal approach course at time of
sighting and full speed for the whole twenty
minutes would have brought us in to 3000 yards and
a fair shot. At 0915 we surfaced and went ahead
at 19 knots on course NORTH, which was the targets
last course, in an endeavor to trail. About 1030
we ran into general rain squalls and reduced
visibility and at 1200 broke off the chase. At
1315(K) sent message to Comsubpac giving contact.
Called on 16460 KCs for 5 minutes, received no
answer, so broadcast message twice. Considerable
interference from Japanese station.
October 6- 0230(K) Having opened to
SW to change R. D. E.
Bearing from TRUK, and not receiving any
indication on Submarine Radio schedule that our
contact report was received, sent report again on
4235 and 8470. Called for 20 minutes, then
transmitted message twice. There was considerable
interference from the Japanese and no report was
obtained.
October 7- 1200(K) Departed Patrol area.
October 8- 0120(K) Having made three
tries at getting off
our message without success, using all the high-
priced help and mechanical aids, we felt pretty
discouraged and had ordered the usual radio
silence. The radioman on watch, on his own
initiative, tuned in on 4235 KCs and listened. He
states that suddenly reception on this circuit
became exceptionally strong, so he grabbed the
message, called Pearl, sent the message and got a
receipt. He then reported his violation of
orders. Held mast and gave him a reprimand for
his offense, and advanced him one grade in rating
for his loyalty, initiative, and ability to get
results.
October 7- 2050(K) Broadcast contact
report twice on 4265
KCs without interference, then called Pearl and
Midway for about 30 minutes. No answer.
October 9- 1240(K) Sighted airplane.
Submerged. Surfaced
at 1600.
October 10- 1700(K) Aircraft contact on
Radar at 2 miles.
Sky almost completely overcast. Submerged.
October 12- 1220(L) With the sky overcast
and squally, sea
rough with lots of whitecaps, sighted a MITSUBISHI
97 two engine, Army heavy bomber close aboard and
headed directly for us. His range was less than 1
mile, position angle 30d. We made a pretty fast
dive. There was a long silence. The only reason
we can attribute to the lack of attacks is that he
was either unarmed or was as surprised as we were.
There was no indication on our Radar. Counting
the O.O.D. there were seven (7) lookouts on the
bridge when the plane was sighted.
October 15- 0945(X) sighted U.S.N. PBY at
about 10 miles. He
passed within about 3 miles without registering on
the Radar. Perhaps the SD Radar is not
functioning.
October 16- 1500(WX) Sighted U.S.N. PBY
and exchanged
recognition. Radar inoperative.
October 16- 1750(VW) Sighted U.S.N. PBY
flying E. altitude
1600 feet.
October 17- 0630(VW) Met escort at rendezvous
and proceeded
to Pearl.
2. WEATHER
ENROUTE TO TRUK: Normal trade weather.
Sea from NE or E,
condition 1 to 3. Trade winds to ENIWETOK, then shifting
Southerly. Sky generally overcast with occasional rain.
ON STATION - TRUK: Glassy sea with
no swells or white caps.
Clear sky with some low clouds on horizon, especially during
night. On the 8th the sea picked up a bit to condition 1,
and
visibility decreased. Very little breeze at night, humidity
high. During the 9th the wind died down and the sea again
became
flat and glassy. Rainy and overcast on the night of 10-11
September, with sea condition 1, and NW breeze. During the
day
the wind shifted to Southerly and sea became good for periscope
observations for the first time. By the 12th the Sea was
condition 2, with white caps. Sky overcast and visibility
spotty, but where clear of rain squalls horizon visible for 15-20
miles. Winds remained variable in strength and direction.
During later part of September there was
considerable rain,
with shifting winds and seas, alternated with short periods of
flat calm. Rain squalls covered large portions of the horizon,
with visibility greatly reduced. This was no particular handicap
until we tried to follow the RYUJO on the surface. We ran
afoul
of an area of reduced visibility that morning entered it at 1030,
and remained in it until the chase was abandoned at 1200.
During
this period the visibility was variable between 100 and 3,000
yards.
ENROUTE TO PEARL: The sky was almost
completely overcast
with much rain and reduced visibility the entire trip. From
TRUK
to TAONGI the sea was calm, with slight swells from S and SE.
After passing TAONGI the sea shifted to E and became moderately
rough, condition 3 to 5. Normal trade winds were encountered
north of Latitude 15dN.
3. TIDAL INFORMATION.
The normal set was in the direction of
the prevailing wind,
generally toward NW with drift from 0.4-0.7 knots. In the
passage between NAMONUITO and HITCHFIELD-GRAY FEATHER Banks and
inshore west of TRUK strong Easterly sets were encountered
regardless of the wind and surface condition of the sea.
4. NAVIGATIONAL AIDS.
TOL Island, TRUK was in sight a good portion
of the time on
station. Ordinarily the peak could be sighted from 35 to
40
miles, and was very valuable as an aid in checking position.
ULUL Island, NAMONUITO, was sighted about 9 miles off and is an
excellent landmark.
No other Navigational Aids were noted.
5. ENEMY SHIPS SIGHTED:
TIME &
DATE : Position :Course:Speed:
DESCRIPTION : REMARKS
----------------------------------------------------------------------
0525(K) :15 Miles WNW : :
:2400 ton tanker :Escorted by one
6 Sept. :of TRUK enr- : 145d : 10 :loaded, similar
:airplane. Hit by
:oute PIAANU :
: :to that of plate:at least one and
:PASS
: : :577 except
with :probably two
:
: : :only one
stack. :torpedoes.
:
: : :One gun
about 3":
:
: : :mounted
at bow. :
----------------------------------------------------------------------
1015(K) :12 Miles W :
: :2500 ton freight:Escorted by one
14 Sept.:of PIAANU : 135d- : 10 :er similar
to :airplane and a
:PASS
: 110d : :SENSEI MARU
:surface patrol.
:
: : :listed
on plate :
:
: : :163.
:
----------------------------------------------------------------------
2225(K) :Lat. 7-43N :
: :6500 ton freight:Passed about 200
20 Sept.:Long. 150-36E: 135d : 12 :er similar to
:yards abeam
:
: : :KEIYO
MARU :during bright
:
: : :listed
on plate :moonlight. Sunk.
:
: : :69.
:
----------------------------------------------------------------------
0010(K) :Lat. 7-43N :
: :Single stack :Seen at about
21 Sept.:Long. 150-36E: - : 25 :ship
of about :4,000 yards in
:
: : :700 tons
oil :moonlight. This
:
: : :burning.
:was the escort
:
: : :163.
:of the above
:
: : :
:listed ship.
----------------------------------------------------------------------
2200(K) :Lat. 8-30N :
: :Patrol boat :
24 Sept.:Long. 150-24E: 270d : 12 :similar to our
:
:
: : :old 110
ft S/M :
:
: : :chasers.
Very :
:
: : :long and
low :
:
: : :with single
:
:
: : :stack
and bridge:
:
: : :structure
slight:
:
: : :ly forward.
:
----------------------------------------------------------------------
0545(K) :Lat. 7-58N :
: :Aircraft tender :Unscreened.
30 Sept.:Long. 151-02E: 170d- : 18 :CHIYODA. No
:Headed for NORTH
:
: 075d : :planes on deck. :PASS, TRUK. Five
:
: : :
:aircraft seen in
:
: : :
:area during this
:
: : :
:period.
----------------------------------------------------------------------
1535(K) :8 miles west : :
:Fishing boat of :
3 Oct. :of ULUL : 330d
: 8 :about 150 tons. :No armament
:Island
: : :Rounded
bow, :noted.
:NAMONUITO
: : :elevated
fore- :
:
: : :castle,
2 masts :
:
: : :with fore
about :
:
: : :50 ft.
and main :
:
: : :about
30 ft.high:
:
: : :Two booms
rigged:
:
: : :from amidships
:
:
: : :at angle
of :
:
: : :about
45d. :
----------------------------------------------------------------------
0654(K) :Lat. 9-15N :
: :Aircraft carrier:No aircraft on
5 OCT. :Long. 149-00E: 345d- : 14 :RYUJO and two
:flight deck. All
:
: 000d : :AMAGIRI class :four
masts up.
:
: : :destroyers.
:
----------------------------------------------------------------------
6. Description of all aircraft sighted,
including type,
position, course, altitude and time of sighting.
TIME &
DATE : POSITION : TYPE
:COURSE: ALTITUDE : REMARKS
----------------------------------------------------------------------
1500(VW):Lat. 20-50N : USN :080d :2000 feet
:
23 Aug. :Long. 159-30W: PBY :
: :
----------------------------------------------------------------------
1510(VW):Lat. 20-35N : USN :080d :2000 feet
:
23 Aug. :Long. 159-35W: PBY :
: :
----------------------------------------------------------------------
1830(M) :Lat. 14-30N : - :
- : - :Radar contact
100
29 Aug. :Long. 170-05E: :
: :miles east
of TAONGI
----------------------------------------------------------------------
0625(L) :Lat. 12-45N : Large :000d :3000 feet :Sighted
at long range
31 Aug. :Long. 161-05E: plane : :
:Position 60 miles
:
: : :
:North of ENIWETOK.
----------------------------------------------------------------------
0600(L) :Lat. 11-30N : - :
- : - :Radar contact.
1 Sept.:Long. 158-00E:
: :
:
----------------------------------------------------------------------
0525(K) :15 miles WNW : - : East:2000 feet
:Sighted while making
6 Sept.:of TRUK. :
: :
:approach. Did not
:
: : :
:observe closely.
----------------------------------------------------------------------
0750(K) :40 miles WNW :Reconn-: NE :2000 feet :
8 Sept.:of TRUK. :ais-
: :
:
:
:sance : :
:
:
:bomber : :
:
:
:type 95: :
:
:
:single : :
:
:
:float : :
:
:
:biplane: :
:
----------------------------------------------------------------------
1025(K) :12 miles W :Reconn-: East:1000 feet
:Air screen for
14 Sept.:of PIAANU :ais- :
: :freighter.
:PASS, TRUK
:sance : :
:
:
:bomber : :
:
:
:type 95: :
:
:
:single : :
:
:
:float : :
:
:
:biplane: :
:
----------------------------------------------------------------------
0520(K) :45 miles WNW :Small, : West:4000 feet :Formation
flight
30 Sept.:of TRUK. :fast :
: :observed
at long
:
:planes : :
:range.
----------------------------------------------------------------------
0745(K) :40 miles WNW :Single : East:2000 feet :
---
30 Sept.:of TRUK. :float :
: :
:
:sea- : :
:
:
:planes : :
:
:
:(95) : :
:
----------------------------------------------------------------------
0850(K) :35 miles WNW :Single : East:4000 feet :
---
30 Sept.:of TRUK. :float :
: :
:
:sea- : :
:
:
:planes : :
:
:
:(95) : :
:
----------------------------------------------------------------------
0700(K) :35 miles WNW :Small : East:2000 feet :
---
1 Oct. :of TRUK. :sea-
: :
:
:
:plane : :
:
----------------------------------------------------------------------
1240(K) :Lat. 12-35E :Unident: East:3000 feet :Sighted
at long range
9 Oct. :Long. 158-50E:ified :
: :
----------------------------------------------------------------------
0700(L) :Lat. 14-00N : - :
- : - :Radar contact
at two
10 Oct. :Long. 162-30E: :
: :miles.
----------------------------------------------------------------------
1220(K) :Lat. 15-50N :Two :South:3000-4000
: ---
11 Oct. :Long. 171-34E:motored:west :feet.
:
:
:bomber : :
:
:
:similar: :
:
:
:to MIT-: :
:
:
:SUBISHI: :
:
:
:97 Army: :
:
:
:Heavy : :
:
:
:bomber : :
:
----------------------------------------------------------------------
0945(X) :Lat. 19-20N : USN : East:2000 feet
: ---
15 Oct. :Long. 168-00E: PBY :
: :
----------------------------------------------------------------------
1500(WX):Lat. 2035 N : USN : East:1200 feet
: ---
16 Oct. :Long. 161-24E: PBY :
: :
----------------------------------------------------------------------
1750(VW):Lat. 20-35N : USN : East:1600 feet
: ---
16 Oct. :Long.161-16.5: PBY :
: :
:E
:
----------------------------------------------------------------------
7. SUMMARY OF S/M ATTACKS.
Listed on printed form herewith attacked [sic] as enclosure (A).
8. ENEMY A/S MEASURES.
Radar contacts indicated an A/S air patrol in the vicinity
of
TRUK during twilight hours. This apparently covered a distance
of but
a few miles beyond the reef.
There is apparently a periodical sweep of the area by an
offshore
A/S air patrol during daylight which is infrequent.
Ships are escorted during daylight by aircraft and by a surface
patrol. One incoming ship made a rendezvous 60 miles West
of TRUK at
midnight with an A/S patrol boat of about 700 tons.
Surface patrols of small craft pass through or patrol the
area at
infrequent intervals. It is possible that those heard and
seen were
either meeting, or had completed escorting, surface vessels.
The presence of an airplane in the area usually meant that
surface vessels were in transit.
No echo ranging was heard during any part of the patrol.
We encountered only one patrol that actually stopped to listen.
It was acting as an escort. We heard ships at ranges varying
from
3,000 to 12,000 yards, but there was no indication that we were
heard
by sound.
Only one depth charge attack was encountered, and on that
the A/S
vessel dropped charges at random with none inside our 1000 yard
range.
The area north of MARSHALL'S is patrolled by air. Indications
are that planes encountered were from ENIWETOK and possibly TAONGI.
9. MAJOR DEFECTS EXPERIENCED.
1. Torpedo tube number 1.
Tubes 1, 2, and 3 had been made ready
for firing during the
approach on September 14, but were not fired. After surfacing
the
torpedoes were examined in rotation.
Two tubes in each end are habitually kept ready for firing
except
for opening the outer door and air master solenoid valve.
Forward
tubes 3 and 4 are the ready tubes. While 3 was being checked,
number
1 was made ready as the standby tube. Number 3 was checked
and
preparations made to fire a 25-50 pound inboard slug. Instead
of
raising the firing interlock and firing number 3 by hand, this
was
inadvertently done on number 1 instead. There was quite a
bang, and
tube number 1 flooded.
The torpedo officer was lowered over the side for external
examination. He found the shutter intact, but the outer door
sprung
about 1 1/2 inches.
This tube was pumped down and the inner door opened.
The torpedo
had traveled forward about 3 or 4 inches, and there was indications
that the torpedo had started a hot run which was speedily terminated
by the over speed trip.
Several hours were spent in attempting to back the torpedo
out of
the tube, without results. When a 1 1/2 ton chain fall failed
to
budge the torpedo the attempts were abandoned.
This piece of gross carelessness has cost the ships [sic]
the use
of this one tube, and probably the wreckage of one torpedo.
The full
extent of the damage cannot be determined until return to port.
2. Bow buoyancy operating linkage failed to function
properly
and the vents would not open. The manhole cover was removed.
The
cause of failure will be investigated and remedied on return to
port.
3. HARDIE-TINE H.P. air compressor.
Trouble continues with the discharge valve
discs. A total of
seven (7) first stage discs were broken during the patrol.
4. The ship's Hull Exhaust Ventilation system does
not remove
battery gases from forward battery when charging at the finishing
rate
and ventilating inboard. This condition can be corrected
by
installing dampers in the exhaust ducts in the pump room and galley.
5. SJ Radar caused considerable difficulty. The
turning gear is
of faulty design and becomes almost impossible to turn. The
antenna
tuning was thrown out of adjustment early in the patrol and without
a
willing target it is impossible to re-tune. Probably the
major source
of trouble came from improper operation by unskilled personnel,
the
whole unit will require checking and tuning. A small turning
motor
would be a distinct asset.
10. COMMUNICATION.
Radio reception - Radio reception of the NPM Fox Schedules
was
very good and was complete. The 8 megacycles were used during
almost
exclusively on station. 12 megacycles were used during the
day to and
from station and occasionally during the early morning while on
station. Low frequency reception depended on weather conditions.
Low
frequency was seriously interfered with by the SD Radar.
High
frequency suffered very little interference.
Interference was encountered from enemy stations when
transmitting on 4235 series. No interference was encountered
on 4265.
Last serial received OCHER 031911 of Oct.
Last serial sent ANDROID 140930 of Oct.
11. SOUND CONDITIONS AND DENSITY LAYERS.
In general, sound conditions varied from good to excellent.
Propellers were picked up at ranges varying from 3000 to 12000
yards.
At times there was a marked variation in sound intensity of a steady
propeller beat, with sound fading in and out. It was being
stopped
and started.
There were some sounds heard which were not caused by ships,
these taking the form of grunts, groans, and clicking, but they
were
the exception and not the rule. They were heard in far less
quantity
than experienced in some other patrol areas.
Temperature gradients were measured daily. The water
temperature
remained 85d F. to 150 ft., with a rare gradient, except that a
layer
of water of 86d F could be found of about 30 feet thickness at
depth
varying between 60 and 120 ft. Sometimes a change in density
of the
water could be felt through a change in the trim but not indicated
by
temperature change of the water.
The fading of propeller noises is believed to have been caused
by
skip distances. Under conditions of zero temperature gradient,
there
results a bending up of the sound beam. This causes the beam
to stay
near the surface and bounce and re-bounce off the underside of
the
sea's surface. A sort of "skip distance" at a projecter [sic]
depth
of 68 feet could easily occur under such conditions.
In general, it is felt that the sound conditions in the area
to
the Northwest of TRUK are favorable for submarine operations.
Submarine listening conditions varied from good to excellent, while
the positive velocity gradient (resulting from a zero temperature
gradient) combined with the ever present density layer at a convenient
depth would offer a fairly safe sanctuary against listening or
echo-
ranging by surface craft.
12. HEALTH AND HABITABILITY
During the early part of the patrol colds were numerous.
As soon
as we became acclimated and took proper precautions these cleared.
There were no serious illnesses. One man had a small Furuncle
on his
right buttocks which required lancing, and one Electricians's Mate
suffered a second degree burn on his hand and was temporarily blinded
by flash when he drew an arc in pulling a fuse from the auxiliary
power board on a hot circuit.
Habitability was good. The average submerged temperature
was
about 90dF., with humidity decreasing shortly after diving.
The air
conditioning units were operated at capacity and were just adequate.
On several occasions one air conditioning unit had to be secured
for
repairs, and it was not very comfortable at this time.
13. Miles steamed enroute to and from station.
Miles steamed enroute to station 3,109.
Miles steamed enroute from station 3,075.
14. FUEL OIL EXPENDED.
Fuel oil
expended enroute station - 28,633.
Average
speed - - - - - - - - - - - 12.9 knots.
Fuel rate
- - - - - - - - - - - - - 9.22 gallons/mile.
NOTE: Conditions
were ideal. Clean bottom, smooth sea,
wind and sea from astern, and set in direction
of travel.
Fuel oil
expended returning from station 37,052 gals.
Average
speed - - - - - - - - - - - - - - 12 knots.
Fuel rate
- - - - - - - - - - - - - - - - 12.05 gals.
per mile.
Three fourths
of the return trip was made against head
winds and seas, with adverse set.
Some three and four engine
speeds were used.
15. FACTORS OF ENDURANCE REMAINING
Torpedoes
- - - - - - - - - - 17 (one probably wrecked)
Fuel
- - - - - - - - - - - - 16,295
Provisions
- - - - - - - - - 30 days.
Fresh water
- - - - - - - - - 1000 gallons. This is no
longer a
factor of endurance unless the stills break
down or
become dirty. We could have ended the patrol
with 10,000
gallons of water if we had desired.
Personnel
- - - - - - - - - - 10 days.
16. The patrol was ended by the time
written in the
operation order.
17. REMARKS.
From departure for patrol on August 23rd
until about
September 30th this was a routine patrol, marred only by the
unfortunate accident to No. 1 torpedo tube on September 14th.
During
this period we sunk one medium freighter and got one or two hits
on a
small tanker. The remainder of the patrol was a fiasco.
On the 30th
we sighted the CHIYODA. Actually it was not possible to get
within
torpedo range, but that was the bad luck of initial position and
subsequent target movements, which is an excuse but not a suitable
result. Then I decided to patrol West of NAMONUITO and to
try to find
out where ships were coming from. After sighting various
small craft,
suddenly on the 5th there came onto view the RYUJO heading for
the
Empire. Had I but required a more rigorous and alert watch
we might
have picked her up sooner. Had I correctly estimated the
situation
and made a more aggressive approach we could have gotten in a shot.
Had I taken up the surface chase without allowing over an hour
to
elapse we might not have lost the target. Had I continued
the search
through the rain squalls until dark we might have picked her up
again.
None of these happened and the second target proceeded unharmed.
The
rest of the time allotted to the patrol was spent in changing position
and attempting to transmit the information on the contacts to the
Task
Force Commander.
In studying over both approaches I find
that they each
conform to my normal method of attack, and confronted with the
same
situations again the results would probably be identical.
18. The Loop antenna was not used
on this patrol. On
previous tests it has given excellent reception at depths to 58
feet,
where fading begins. All our submerged patrolling was done
at 62 feet
or deeper, so there was no occasion to use this loop.
FC5-10/A16-3(FB5-102) SUBMARINE SQUADRON TEN
Serial 043
Care of Fleet Post Office,
San Francisco, California,
October 20, 1942.
CONFIDENTIAL
From: The Commander Submarine
Squadron Ten.
To : The Commander Submarine
Force, Pacific Fleet.
Subject: U.S.S. WAHOO (SS238) - First War Patrol
- Comments on
1. The WAHOO's
patrol covered a total of fifty-five days, of
which thirty-four were spent on station. The last
four days were spent patrolling to the westward of the assigned
area.
More time should have been spent in closer proximity to Piannu
[sic]
Pass.
2.
In the attack on September 6, there is insufficient
evidence to support a belief that a hit was obtained upon the tanker.
the masthead height was probably underestimated.
3. On September
14, sea and weather conditions are not
stated. Under certain conditions, when an aircraft screen
is known to
be present, the practice of going deep between periscope observations
is sound. However, to resort to an approach wherein no periscope
observation is made for thirty-two minutes invites failure.
4. The attack on
the freighter which was sunk was conducted
in such a way as to indicate that again ranges were in error.
If
ranges had been more accurate, a more favorable firing position
would
have been obtained. It appears that the firing mechanism
of the first
torpedo failed to arm due to the short run. The subsequent
tactics
used in evading the escort were well conducted.
5. To get in an
attack on such a valuable target as an
aircraft carrier calls for the greatest degree of aggressiveness.
The
fact that the RYUJO was not sighted until at a range of 11,000
yards
bears out the Commanding Officer's statement that a more alert
watch
could have been kept.
6. It is regretted
that so much difficulty was encountered in
the operation of the SJ Radar. This has greatly handicapped
the WAHOO
since valuable training in the use of this equipment has been missed.
During the current refit period, Radar personnel should receive
special instruction in its use. A training motor will be
installed if
available.
7. The excellent
material condition of the WAHOO upon return
from patrol is commendable. The following damage is considered
as
done the enemy:
SUNK
1 Freighter ............ 6,500 tons.
CONFIDENTIAL
From: The Commander Submarine
Division ONE HUNDRED TWO.
To : The Commander Submarine
Force, Pacific Fleet.
Subject: U.S.S. WAHOO (SS238); First War Patrol, Comments on
1. The WAHOO spent
34 days in or in vicinity of the assigned
area. During this period five worthwhile torpedo targets
were
contacted. Two of the targets were extremely valuable vessels,
the
RYUJO and CHIYODA. Of the five, one 6500 ton freighter was
sunk.
More targets probably would have been sighted had Piaanu Pass been
kept under closer observation then shown in the track chart.
2. Japanese tankers
and other fast auxiliaries have been
observed to be carrying depth charges which they apparently drop
either to embarrass the attacking submarine or to countermine
approaching torpedoes. This might have been the tactics employed
by
the small tanker attacked on the morning of September 6th and is
offered as an explanation of the two delayed explosions which were
heard one minute after torpedoes were estimated to have crossed
the
track.
3. It is very unfortunate
that attack positions were not
attained on either the CHIYODA nor RYUJO. In the case of
the former,
luck alone was the factor that saved her from certain destruction
or
severe damage. In the case of the latter, the situation upon
sighting
indicated that attack position, if attainable, could be gained
only by
the most aggressive kind of approach. It is regrettable that
the need
for such immediate action was not recognized.
4. S.J. Radar.
It is regretted that so much difficulty was
experienced with the S.J. Radar. Had the radar been kept
in operation
condition it might well have made the desired contact with RYUJO
at
noon on October 5th. No effect should be spared to keep this
valuable
instrument in perfect operating condition throughout a patrol.
In
regard to the tuning of the system it is suggested that the proximity
of any high land in the patrol area at night will provide the
"willing" target required for this purpose. The urgent need
for
trained radar maintenance men in submarines is again noted.
5. While the patrol
was not outstanding in either results or
aggressiveness it is certain that the resultant seasoning of the
officers and crew has prepared them to most any situation on future
patrols with resolution and effectiveness.
6. MATERIAL.
WAHOO will be refitted by SPERRY assisted as
necessary by the Navy Yard.
It is assumed that steps have been taken to prevent a
repetition of the gross carelessness which placed tube number 1
out of
commission.
Serial 01249
Care of Fleet Post Office,
San Francisco, California,
1 November 1942
COMSUBPAC PATROL REPORT NO. 83
U.S.S. WAHOO - FIRST WAR PATROL
CONFIDENTIAL
From: The Commander Submarine
Force, Pacific Fleet.
To : Submarine Force,
Pacific Fleet.
Subject: U.S.S. WAHOO (SS238) - Report of First War Patrol.
Enclosure: (A) CSS-10 Ltr.File FC-10/.16-3(043) of 26
Oct. 1942
(B) CSD-102 Ltr. FB5-102/A16-3(1) Serial 016 of
October 20, 1942.
(C) Subject Patrol Report.
1. The Commander
Submarine Force, Pacific Fleet, agrees with
the comments of Commander Submarine Division 102 and Commander
Submarine Squadron TEN that more time on this patrol should have
been
spent in close proximity to PIAANU PASS.
2.
A successful attack on the RYUJO would have had far
reaching results and it is unfortunate that the WAHOO failed to
press
home an attack in this instance. Opportunities to attack
an enemy
carrier are few and must be exploited to the limit with due acceptance
of the hazards involved. The Commanding Officer realized
his mistake
in the instance, as noted in paragraph 17 of the report.
The lesson
learned by this experience should impress on all Submarine Commanding
Officers the necessity for continuous alertness, and quick, positive
action immediately when a contact is made.
3. Firing of four
single torpedoes in the attack on September
20th undoubtedly resulted in the needless expenditure of torpedoes
over what would have been required to obtain the same results had
a
torpedo spread been used in the initial attack.
4. The WAHOO is
credited with having inflicted the following
damage on the enemy:
SUNK
1 Freighter 6,441 tons
R.H. ENGLISH.
DISTRIBUTION
(35CM-42)
List III: SS
Special
P1(5), EN3(5), Z1(5),
Comsublant (2)
Comsubsowespac (2)
** signature **
E. R. SWINBURNE,
Flag Secretary