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Gulf of Tonkin, USS Maddox Reports for 2 and 4 August 1964

Related Resources:

Formerly Classified Documents Subsequent to 4 August

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USS Maddox "Report of Action, Gulf of Tonkin, 2 August 1964" dated 24 Aug.:

U.S.S. Maddox (DD 731)
C/o Fleet Post Office
San Francisco, California

DD731/DMJ: fs
Ser: 003
24 August 1964


From: Commanding Officer, USS Maddox (DD 731)
To: Chief of Naval Operations
Via: (1) Commander Destroyer Division ONE HUNDRED NINETY-TWO
(2) Commander Task Group SEVENTY-TWO
(3) Commander SEVENTH Fleet
(4) Commander in Chief, U.S. Pacific Fleet

Subj: Report of Action, Gulf of Tonkin, 2 August 1964

Ref: (a) COMSEVENTHFLT msg 170531Z July 1964

Encl: (1) DRT trace of action [not attached]
(2) Close-up Photograph of Damage to Mk 56 Director Pedestal [not attached]
(3) Photo of Mk 56 Director [not attached]

USS Maddox (DD 731) 2 AUGUST 1964

1. On 2 August, the Maddox was conducting a routine DESOTO Patrol in international waters in the Gulf of Tonkin, in accordance with instructions found in reference (a). The primary purpose of the patrol was to determine the coastal patrol activity furnished by the Democratic Republic of Vietnam (DRV) along the North Vietnam coast. Other intelligence requirements included collecting ELINT and hydrographic information, monitoring of junk density and junk traffic patterns, conducting radarscope photography, and photographing landmarks. (At no time that day did Maddox approach the mainland nearer than 8 nautical miles or an island nearer than 4 miles.)

2. Our own forces in the area included CTG 72.1 (COMDESDIV 192) embarked in the Maddox; CTF 77 (COMCARDIV 5) embarked in the Ticonderoga (CVA 14), operating in the vicinity of 16'N, 110'E; the C. Turner Joy (DD 951) on station at 17 [degrees] 30'N 108 [degrees] 00'E; and the Samuel N. Moore (DD 747) on station at 17 [degrees] 30'N, 109 [degrees] 40'E.

3. During the morning of 2 August, the Maddox proceeded northward towards Point DELTA (19 [degrees] 47'N, 106 [degrees] 08'E) arriving in the vicinity at 1145I and then turned south on the first leg of an 8 hour orbit. The Maddox continued in a southerly direction during the early afternoon headed for a point 4 miles seaward of HON ME. About 1330I three patrol craft believed to be motor torpedo boats were sighted to the northwest, also on a southerly course apparently headed towards HON ME. The Maddox reversed course and headed back towards Point DELTA on a northeast heading. At 1350I two more patrol craft, believed to be Swatow patrol boats, were sighted to the northwest and they were also apparently headed towards HON ME. The three PT boats and the two Swatow PGM's were tracked by radar into a cove on the north side of HON ME. At 1445I the Maddox altered course 35 degrees to starboard to avoid a large junk fleet fishing in the vicinity of Point DELTA. By 1600 the Maddox was 12 miles due east of Point DELTA still headed on a northeast course when a radar contact bearing 230 range 30 miles was detected just north of HON ME. The contact was tracked on a course of 050, speed 30 knots and it was evaluated as a probable patrol craft due to its high speed.

NOTE on speed and other characteristics of Tonkin Gulf vessels:

Gulf of Tonkin junks are of two basic sail powered types which generally operate in fleets of twenty to one hundred. Within the fleets the junks operate in pairs when towing a large trawl net between the boat. When engaged in trawling, the net acts much like a large sea anchor and prevents the junks from making more than a few knots through the water. Junks not fishing and under full sail can make about 6 knots. Tonkin Gulf junks are very similar in appearance to the South Vietnam types, VTAC-2 and PTBC-la as shown in the OSOD Junk Blue Book.

Two types of PT boats are known to belong to the DRV Naval Forces which operate in the Gulf. The P-4 class is a 50 knot (plus) boat which carries two 18" torpedoes and two 12.7 mm twin guns. The P-6 class has a maximum designed speed of 43 knots. It carries two 21" torpedoes, two 25 mm twin guns and is equipped with radar (Skinhead).

There is a third type of vessel, the PGM "Swatow" class patrol boat which has a speed of 25 knots, a Skinhead radar, and 37 mm guns. It is believed that these slower craft are used to vector the PT's in to their target during night engagements, leaving the last moments of the run-in up to the individual PT to make their own adjustments for the attack solution. It is further believed that the PT's reposition themselves for subsequent attack by first seeking the fresh wakes of the target vessels, getting their "bearings", and then opening out for another attack.

During the next 45 minutes the Maddox increased speed from 10 knots to 25 knots and headed east momentarily and then southeast in order to open the contacts which also were increasing speed and closing. By 1700I, the Maddox was 25 miles from the DRV coast, headed southeast at 27 knots. The contacts could be seen visually bearing 269, range of 8 miles, and they were being tracked by the Fire Control radar on a closing course of 120 with a speed of 50 knots. It was apparent that the contacts were motor torpedo boats and that they were intercepting the Maddox. By 1705 the boats were identified as three P-4's in column formation. They had closed to 9800 yards off the starboard quarter at which time the Maddox fired three 5"/38 caliber warning shots which were unheeded.

4. The torpedo boats continued to close and were taken under fire with 151 5" rounds and 132 3" rounds of continuous fire. Although receiving numerous hits and near misses, two boats (second and third in a column) closed to 2700 yards and, because of the volume of fire, only the second boat was able to launch torpedoes. The lead boat received a direct hit at 3000 yards as it launched a third torpedo, the torpedo was not observed to run. The first two torpedoes passed near the starboard side after the Maddox turned to evade. During the attack, 12.7 mm machine gun fire was also directed the Maddox, but resulted in only one hit and no casualties. After having turned away, the first and third boats slowed apparently to assist the second boat which had been hit and had retired earlier. The Maddox turned and pursued the boats for 4 minutes after it was known that the torpedoes had cleared. By this time the high relative opening range rate had opened the boats to 5 miles. At 1729I the pursuit was broken off because of the possibility of spent torpedoes in the area and that carrier aircraft had started their strafing runs. The Maddox remained in the area in order to render possible assistance to damaged or downed aircraft and then retired to the southeast.

USS Maddox (DD 731) ACTION ON 2 AUGUST 1964

1315I Steaming independently in the Gulf of Tonkin, conducting DESOTO Patrol Course 205, speed 10 knots. Position 19 [degrees] 33.3'N, 106 [degrees] 07.1'E.

1330I Sighted and tracked on radar three patrol craft. Patrol craft bearing 306, 9.4 miles, course 190, speed 20 knots. Position 19[degrees] 30.7'N, 106 [degrees] 05.7'E. Later identified as probable P-4 class torpedo boats.

1340I c/c 020.

1345I Position 19 [degrees] 28.8'N, 106 [degrees] 05.1'E.

1350I Radar contact held on two patrol craft bearing 333, 17 miles, course 190, speed 15 knots. Later identified two Swatow PGM class.

1400I Position 19 [degrees] 31.1'N, 106 [degrees] 06.2'E.

1415I Position 19 [degrees] 33.1'N, 106 [degrees] 07.5'E.

1422I Tracked all patrol craft by radar into HON ME.

1430I Position 19 [degrees] 36.1'N,106 [degrees] 09'E

1445I Position 19 [degrees] 38.2'N, 106 [degrees] 9.9'E.

1455I c/c 050 to avoid fishing boats.

1500I Position 19 [degrees] 40.3'N, 106 [degrees] 11.5'E.

1515I Position 19 [degrees] 41.8'N, 106 [degrees] 13.6'E.

1530I Position 19 [degrees] 43.3'N, 106 [degrees] 16.1'E.

1545I Position 19 [degrees] 45.2'N, 106 [degrees] 18.6'E.

1549I c/c 047.

1600I Position 19 [degrees] 47'N, 106 [degrees] 20.6'E. Radar contact bearing 230, range 30 miles approaching on course 050, 30 knots. Three contacts evaluated as PT boats, about 10 miles north of HON ME.

1615I Position 19 [degrees] 48.8'N, 106 [degrees] 22.5'E.

1623I c/c 090.

1625I c/s 15 knots.

1627I c/c 105.

1630I Position 19 [degrees] 49.4'N, 106 [degrees] 26.4'E. Set condition 1AA, General Quarters.

1633I Held boats on radar 239, 19 miles, course 040, 33 knots. Boats are opening concentration of junks.

1638I c/s 20 knots.

1640I Designated target to fire control.

1642I c/s 25 knots.

1645I c/c 130. Position 19 [degrees] 51'N, 106 [degrees] 30'E. Acquired target with fire control radar, bearing 255, range 13.3 miles.

1647I Requested immediate air support from the Ticonderoga, four airborne F8E's were detached to assist.

1650I c/s 27 knots. The target boats were 261, 11 miles, course 090, 46 knots and appeared to be weaving.

1659I c/c 150. (Note: After director (Mk 56) acquired and shifted to the second boat; the forward director (Mk 37) was tracking the first boat. The boats had returned to a column formation, bearing 269, range 16700 yards, course 120, speed 50 knots).

1700I Position 19 [degrees] 45'N, 106 [degrees] 34.5'E. Experienced jamming on the CID net.

1705I Fired three warning shots. Target 266, range 9800 yards.

1708I Commenced continuous fire. Target course 126, 47 knots, bearing 266, 9000 yards. AN/SPS 40 interlocks tripped, lost the air search radar and the Mk 10 IFF.

1713I Boats returned fire with 12.7 mm machine guns; projectiles fell short. Boats were identified as P-4 class each with radar and machine guns. The first boat was noticed by Main Battery Director officer to have a larger caliber gun, not manned, probably a 37 mm. Engine exhausts were noticed forward of the cockpits, outboard. (Photos confirmed they were P-4's.)

1715I Position 19 [degrees] 36'N, 106 [degrees] 39.5'E. Made direct hit with 5" AAC on second boat causing it to swerve left in an almost complete circle and slow. It was effectively removed from action; however, it was seen to launch two torpedoes when it was hit. The second boat eventually increased speed and retired to the north before it lost all power. Hits were also noted over the third boat.

1717I The third boat turned left and passed close under the Maddox stern without having launched torpedoes. The after director shifted to the first boat which returned fire and turned toward the Maddox.

1717I c/c 110 to avoid torpedoes fired by the second boat.

1720I Observed two parallel torpedo wakes passing up the starboard side about 200 yards.

1720I Made a direct hit on the first boat bearing 195, range 2000 yards. Observed a torpedo to be either launched or blown over the side; however, the torpedo apparently did not run. The first boat turned under the Maddox stern, raking the ship as it passed. Closest point of approach was 1700 yards. The Mk 56 director pedestal received one hit. The 12.7 mm projectile richocheted down into the 3"50 ready service magazine.

1722I c/c 150.

1727I c/c 330 to pursue.

1728I c/c 315. Aircraft made their first attack.

1729I c/c 180, position 19 [degrees] 36.8N, 106 [degrees] 38'E, pursued one mile before retiring south. F8E's jets made first attack. c/s 20 knots. Set pilot rescue team. Broke off pursuit to permit the aircraft a clear field for their attack and to avoid spent torpedoes still in the area.

1733I c/s 20 knots.

1734I c/c 310.

1735I c/c 180.

1739I c/s 25 knots.

1742I Aircraft departed the area.

1745I Position 19 [degrees] 35'N, 106 [degrees] 39'E.

1748I c/c 150.

1800I Position 19 [degrees] 26'N, 106 [degrees] 40.6'E.


1. 5"/38 VT frag and AAC ammunition and 3"/50 VT frag were used against the enemy PT boats. The 5"/38 AAC was fired with the fuze setters set on manual and safe. The 5"/38 mounts fired approximately 50% VT frag and 50% AAC. This selection of projectiles was effective at the initial firing ranges of from 8,000 to 10,000 yards. However, as the target range decreased to 5,000 yds and less, several 5" and 3" VT frag projectiles exploded early due to their proximity to the surface. This was caused by the low trajectory path at decreased ranges. The rapid rate of fire of the 3"/50 twin gun mount (Mt. 33) accounted for heavy saturation of the target area, and because of this, the 3"/50 VT frag was very effective even with the high number of early bursts caused by the proximity to the surface. Mt. 32 fired 132 rounds of 3"/50 VT frag without a casualty. 5"/38 VT frag was less effective than the 3"/50 Vt frag because of the slower rate of fire. 5"/38 AAC with fuzes set on manual and safe was effective and accounted for a sufficient number of surface bursts along with the air bursts received from the VT frag. The performance of the 5"/38 twin gun mounts was good and the rate of fire was effective until the mounts fired all the ammunition stored in the upper handling rooms. Due to the shortage of men in the present manning level, 5" magazines are not manned at general quarters and the mount crews were required to break out additional ammunition. This hindered the effectiveness of the 5"/38 gun mounts. Mt. 31's gun crew manned Mt. 53's magazine and enabled Mt. 53 to maintain their rate of fire. The 5"/38 mounts fired 80 rounds of VT frag and 71 rounds of AAC.

2. The performance of the Mk 56 GFCS with the Mk 35 radar was very effective. The radar initially acquired target at 26600 yards and remained locked on until designated another target. At 12000 yards the Mk 56 GFCS was designated a second target and took it under fire at 9800 yards. Firing continued until the PT boat was badly damaged and the director was ordered to shift targets. The Mk 56 GFCS immediately locked on to its third designated target and because of its rapid solution time was able to open fire again instantly. At no time during the firing did the radar lose target. The Mk 37 GFCS with the Mk 25 radar and Mk 1A computer initially acquired target at 31400 yards. The radar tracked the target into firing range and the computer acquired solution.

3. The torpedoes fired by the DRV P-4 boats were easily avoided since they were launched at about 27000 yards, from a relative bearing 150, and they were set shallow enough so the wakes could be seen. One was running on the surface but it was not porpoising. Their wakes permitted the conn to judge the time to turn and course to change to in order to evade. Sonar did not hear the torpedoes even though they passed close aboard (100-200 yards) to starboard. The Maddox was at 27 knots throughout the action. Both torpedoes were seen to be launched or to be physically blown over the side of the leading boat (last to attack) when a direct hit was observed. The boat was at a distance of about 2000 yards when it was hit. The torpedo apparently did not run since no wake was seen.

4. Radar was observed on all three boats; however, Skinhead intercepts were not held on the ECM equipment.

5. A larger caliber gun than the 12.7 mm guns in action was seen on one boat. It was mounted aft and was not manned. Judging from the splashes from the machine gun bullets the enemy gunners were consistently sweeping in wide deflection and they were falling just short in range.


1. Aside from the ½" bullet hole in the after director pedestal, no damage was incurred by the Maddox (See enclosure 2 and 3). One DRV P-4 boat received several hits and was observed to be dead in the water and burning. Aircraft also observed the same boat as dead in the water and burning. It is assumed the boat later sunk. Although the other boats received several hits each and both appeared to have been badly damaged, they were able to retreat to the northwest toward North Vietnam.

2. F8E Crusaders from the Ticonderoga attacked the boats while they were still in international waters. One aircraft received minor wing damage but was able to continue on its mission. The aircraft made no known Zuni rocket hits on the boats; however, the 20 mm cannon fire looked effective.


1. All personnel manned their General Quarters stations quickly and the topside personnel donned body armour in addition to their regular battle dress. Throughout the ensuing action all personnel performed their duties in the highest traditions of the Naval Service. At no time was there confusion or indifference among the crew in making the instantaneous transition from a routine "cold war" patrol on a Sunday afternoon to an actual enemy attack under war time conditions.


1. Naval Weapons Selection NWIP 20-2 (A) recommends High Capacity with point detonating fuzes or anti aircraft common with mechanical time fuze (MTF) set on "safe" be used against targets such as PT boats. COMCRUDESFLOT 3 Gunnery Doctrine recommends the use of 50% AAC with the MTF set for a 50 foot airburst over the target and 50% VT frag. The Maddox recommends the use of 50% AAC and 50% VT frag for the 5"/38 gun mounts. Of the 50% AAC used, it is recommended that two of the three 5" mounts have fuze setters in automatic with the MTF set for a 50 foot airburst over the target. One 5" mount should have the fuze setter in manual with the MTF set on "safe". This mount would be controlled by the Mk 56 director. This would allow for both air and surface bursts and would inflict greater damage on enemy craft such as PT boats. The air bursts would be effective against enemy personnel and the surface bursts effective against the underwater hull and topside structure of PT boats.

The Maddox also recommends opening fire at maximum effective gun range with one gun mount per director at slow salvo rate of fire. Continue slow salvo rate of fire until hitting range has been established then shift to rapid rate of fire with all mounts available to each director. Due to the shortage of ammunition available caused by present manning level of this class DD, an initial rapid rate of fire before hitting range is established will cause depletion of ammunition before it can be effectively used against the enemy.

LESSONS LEARNED -- 1. For 5"/ 38 twin gun mounts use 50% AAC and 50% VT frag. Have two 5" mounts set with MTF for a 50 foot airburst over the target and one 5" mounts set with MTF on "safe".

2. The rapid rate of fire of the 3"/50 twin gun mount with VT frag causes heavy saturation of the target area and is very effective against PT type boats.

3. Use slow salvo rate of fire with one gun mount per director until hitting range is established, then shift to rapid rate of fire with all gun mounts available.

2. The Enlisted Distribution Plan (EDP) -- Manning level in WestPac for this class destroyer is 193 men. The Bureau of Personnel level is 234 and the wartime complement is 288 men. The ship was undermanned for wartime conditions and this shortage was felt the most by the Weapons Department in the following way. The 5" mounts ran out of ammunition after they had used the ammunition from the ready service magazines (upper handling) rooms. There were not enough personnel on board to man the 5" magazines; however, repair party personnel and mount crews were utilized to pass ammunition and thereby place the 5" batteries back in action. Had the ship encountered more than three boats in a better coordinated attack the shortage of personnel would have disastrously altered the outcome of the engagement.

LESSONS LEARNED – The current manning level of a WestPac DD is not high enough to provide for personnel in the magazines.

3. CIC Equipment: The first 5" salvo tripped every battle interlock and caused a serious water leak in the cooling system of the AN/SPS-40 (air search radar) at a most critical period while CIC was directing the aircraft inbound to assist. Both the radar and IFF were lost. The aircraft's arrival over the targets was delayed while the aircraft had to be homed in over the Maddox by UHF direction finding. The SPS-40 interlocks were tied down in subsequent action, thus permitting air control on the 4 August attack. Tripping of the interlocks and leaks in the fresh water cooling systems of the SPS-40 radar from shock effects has occurred before when the 5" mounts have been fired.

LESSON LEARNED -- The SPS-40 radar equipment is not properly shock mounted.

4. Enemy operational procedures and tactics: The stern approach on a closing course by the P-4's does not seem to be an intelligent tactic because the boats are in DD gun range for a longer time before they are in a position to launch their torpedoes. Their very low silhouette, weaving tactics and high relative speed made the boats difficult targets during the approach until they drew up on the quarter. If they had approached from the bow they would have been harder to hit and also under fire a shorter time. As long as the defending ship has sea room, the best defense is to keep the enemy boats astern or on the quarter as long as possible in hopes of destroying them before they can gain a position on the bow and turn in for the torpedo run. The attacking boats were aggressive and showed no tendency to abort their torpedo run even though they were confronted with a heavy barrage of fire. It was only after the boats were damaged that they broke off their run and passed astern. During the run-in no evasive tactics were used by the P-4. Each P-4 was equipped with a Skinhead radar. The frequency band of this radar was being searched by ECM and no intercepts were made.


1. USS Maddox is unique in that the ship did not undergo a FRAM overhaul similar to other FRAM's. To house the equipment for the AN/SPS-40, additional space was built on the starboard side of the 01 level. The various transmitter sections were installed on the outboard bulkhead. When the forward battery (four 5" guns) are fired in salvo on the starboard quarter the concussion on the forward and outboard bulkheads shakes the equipment to the point that major water leaks develop and the radiate interlock relays open, thus dropping the radar to "ready."On the 2 August action the radar went down on the first salvo, for 40 minutes, while leaks were repaired, the air locks eliminated, and the interlocks taped closed. Equipment specifications presently call for the installation of rubber hose to couple nonflexible tubing in the cooling system. This should solve the problem of the leaks; however, there is no known field change or operating procedure that will prevent the interlock relays from opening other than tying them closed. It is recommended that BUSHIPS investigate the feasibility of a Battle Short Circuit, and shock mounting, if this problem is common enough to warrant it. (Part VI, para. 3 page 9).

2. If further action against this type target is anticipated the installation of the 20 mm cannon is recommended. The 20 mm with its range of 4800 yds (2000 effective) would be highly effective against the maneuverable PT's.


Copy to:
CNO (2)
CTF 77 (1)
COMDESRON 19 [handwritten in copy 12]
COMCRUDESFLOT 3 [handwritten in copy 12]

Source: Tonkin Gulf Collection, 1962-1984 [1964 and 1968], Series I: Misc. Subject Files, 1964, Box 1 of 12, Operational Archives Branch, Washington, DC.

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USS Maddox "July-August DESOTO Patrol..." dated 24 Aug:

U.S.S. Maddox (DD 731)
c/o Fleet Post Office
San Francisco, California

DD731/DMJ: bt
Ser: 002
24 August 1964

From: Commanding Officer, USS Maddox (DD 731) (CTU 72.1.0)
To: Chief of Naval Operations
Via: (1) Commander Destroyer Division ONE HUNDRED NINETY-TWO (CTG 72.1)
       (2) Commander U.S. Taiwan Patrol Force (CTF 72)
       (3) Commander U.S. SEVENTH Fleet
       (4) Commander in Chief, U.S. Pacific Fleet

Subj: July-August DESOTO Patrol conducted during the period 28 July-8 August 1964 (C)

Ref: (a) COMSEVENTHFLT msg 170531Z July 1964
       (b) CTF SEVENTY-TWO msg 210005Z July 1964
       (c) COMSEVENTHFLT msg 230245Z July 1964
       (d) COMSEVENTHFLT msg 022225Z August 1964
       (e) COMSEVENTHFLT msg 031710Z August 1964
       (f) CINCPACFLT msg 032259Z August 1964
       (g) CTF SEVENTY-SEVEN msg 041238Z August 1964
       (h) COMSEVENTHFLT msg 041249Z August 1964
       (i) COMSEVENTHFLT msg 042005Z August 1964
       (j) CINCPACFLT msg 051022Z August 1964
(k) CTF SEVENTY-TWO OPORD 201-64, Appendix II to Annex D

Encl: (1) Narrative of Events
        (2) Navigational Summary
        (3) Visual Contact Log
        (4) Weather Data Sheet
        (5) Surface Search Radar Contact
        (6) Navigation Log
        (7) ECM Intercept Summary
        (8) Photographic Summary
        (9) Air Search Radar Summary
       (10) Overlays
       (11) Brief Action Report, 2 August 1964
       (12) Brief Action Report, 4 August 1964
       (13) USS Maddox NOTE 003500 of 28 July 1964

1. The USS Maddox (DD 731), with CTU 72.1.0 (Commander Destroyer Division 192) embarked as the DESOTO Patrol Commander, conducted a DESOTO Patrol in the Gulf of Tonkin along the East coast of the Democratic Republic of Vietnam (DRV) during the period of 28 July to 8 August 1964. This patrol was conducted in accordance with reference (a), as directed by reference (c) and modified by references (d) through (j). By reference (b), Commander Destroyer Division 192 was redesignated CTG 72.1 on 31 July. On the night of 2 August the USS C. Turner Joy (DD 951) joined the Maddox. Additional units assigned CTG 72.1 were aircraft (on call) and onstation CAP provided by USS Ticonderoga (CVA 14). The mission of the DESOTO Patrol was to collect general and specific intelligence as listed in references (a) and (k). Intelligence collection was interrupted on 2 August by an attack by three DRV torpedo boats. Subsequent movements of the group did not permit the collection of more than an occasional electronic emissions within the threat bands and collection of navigational information in the areas previously patrolled. For reporting purposes the patrol is considered to have been completed on 8 August when the group was ordered south to join Task Group 77.5.

2. TRACK. The patrol commenced as scheduled on the track specified in reference (a). Dog legs between Pt. "B" and "C" and between Pt. "C" and "D" were necessary in order not to approach the DRV mainland closer than 8 miles. Pt. "D" was located inside the 8 mile limit. After arriving in the vicinity of Pt. "D" on 2 August, the Maddox commenced the first leg of its orbit toward HON ME. After approaching about half the distance toward HON ME, the Maddox reversed course to pass near Pt. "D" again on a NE heading. At about 1500I the Maddox changed course to the SE to avoid reported patrol boats. Subsequent to the day action on 2 August the original track was not resumed. A modified track was prescribed by reference (d) which required patrolling from Pt. "C" to "D" on 3 August, from Pt. "D" to "C" on 4 August, and from Pt. "C" to "D" on 5 August. The minimum distance to approach DRV territory was changed from eight to eleven miles. Patrols were to be conducted during daylight with the ships retiring to the East at night. A night attack on the patrol occurred on 4 August. On 6 August the patrol refueled and rearmed in the vicinity of 17N 109E and proceeded back into the Gulf to arrive in the vicinity of Pt. "M" by first light on the morning of 7 August. The patrol proceeded South into the vicinity of Pt. "N" and then retired southeast for the night. On 8 August the patrol arrived off Pt. "N" after sunrise and proceeded South, passing in the vicinity of Pt. "O" and Pt. "P", thus terminating the Gulf of Tonkin operations.

3. Enclosures (1) through (13) contain required reports and overlays of charts depicting the track. Edited fathometer records, the associated navigational track, changes to NavAids, and Bathythermograph slides have been forwarded directly to the U.S. Naval Oceanographic Office. Elint material has been forwarded directly to PACOM ELINT CENTER.

4. Pre-Sail Briefings. A general briefing was conducted by the Elint Center, Fuchu, Japan for the ECM operators. The Naval Security Group, Taiwan Defense Command, and Naval Forces Japan representatives conducted briefings on board the Maddox in Keelung and also in the J-2 section at TDC. Emphasis and clarification of the mission were well covered as was the order of battle of the DRV and CHICOM forces in the Gulf of Tonkin. Additional Elint information covering specific geographical locations was provided by the First Radio Battalion detachment from FMFPAC once the patrol started. Officers of the USS Mc Kenzie provided recommendations and sample logs which were helpful aids during the patrol.

5. Personnel. The following personnel were assigned Temporary Additional Duty to the Maddox:

a. Special teams from the NAVSECGRU, Taipei; the NAVSECGRU, Philippines; and the First Radio Battalion, FMFPAC, operated the security group van.
b. A radarscope photographer was provided by the USS Ticonderoga.
c. A photographer was provided by the Mobile Photo Unit, Pacific.

6. Special Equipment. Equipment utilized in addition to that normally installed included:
a. Naval Security Group Van and associated equipment.
b. 1 -- AN/SLA-2 ECM Pulse Analyzer.
c. 1 -- KD-2 camera for SLA-2.
d. 1 -- CRZ-6 Radarscope camera from the Ticonderoga (CVA 14).
e. 1 -- NIKKO REX F camera.
f. 1 -- NIKON F camera.
g. 1 -- 500 MM lens.
h. 1-- 135 MM lens.
i. 1-- 16 MM Filmo.

7. Logistics.

a. Logistics support prior to the patrol was marginal. The AN/SLA-2 provided by CTU 70.8.1 was not installed and ready until two hours before getting underway. Six AN/SLA-2 Pulse Analyzers were checked before finding one that was in operating condition. This one worked for only a short time before it required repairs to worn parts. Many of the "ready" AN/SLA-2 analyzers had been cannibalized. A radarscope camera was not provided prior to getting underway. A jury-rig was prepared using a personal camera; however, a radarscope camera and a qualified operator were provided by the Ticonderoga on request and transferred to the Maddox via the Ashtabula on 31 August.

b. A harbor pilot was confirmed in the LOGREQ reply but was not furnished. Tugs for assisting the Maddox in shifting berths and for assisting the Mc Kenzie in getting underway were promised but not supplied. This caused a delay due to high winds.

c. Fuel would have been critical had the patrol been carried out in accordance with the schedule of reference (a). It was estimated that the Maddox would have had 34% fuel remaining by 9 August. Even this amount of fuel could have been preserved only by conducting the scheduled orbits at five knots. It is recommended that fuel requirements be considered more carefully in scheduling future patrols.

d. The Maddox was refueled by the USS Ashtabula (AO 51) on 31 July and 3 August; from the USS Kennebec (AO 36) on 6 August; and was rearmed from the USS Moore (DD 747) and the USS Edson (DD 946) on 6 August. The Turner Joy rearmed from the Edson on 6 August.

8. Surface Units Encountered. The majority of the surface contacts encountered were junks and sampans engaged in fishing. No abnormal movement of the junks was observed. On the morning of 31 July, four PT boats were observed that were later evaluated as (Nasty) class PT boats from South Vietnam. In the early afternoon of 2 August three P-4 PT boats and two Swatow PGM's were sighted visually and then tracked by radar into a cove on HON ME. Later that afternoon three PT boats were tracked as they departed the cove on HON ME. These three boats later attacked the Maddox. A brief of this action is contained in enclosure (1). On 3 August a contact, visually identified by an aircraft as a tanker, was tracked into a cove on HON ME.

On 4 August a ship resembling a U.S. Navy YO which was seen leaving HON ME returned to HON ME upon sighting the Maddox. That night the Maddox held several radar contacts which comprised a "trap" and lead to the action of 4 August. A brief of this action is contained in enclosure (12).

9. Air Contacts. Very little DRV air activity was observed. No air contact over DRV territory was held longer than a few sweeps of the air search radar.

10. Elint. The USS Turner Joy joined the Maddox on the night of 2 August and from then to the end of the patrol assisted in the collection of Elint. The two ships intercepted a total of twenty-eight signals, several of which confirmed existing sites. Eleven signals were evaluated as unknown, usually due to lack of sufficient information. One intercepted signal appeared to be an EW radar with moving target indication capability, ECCM capability, or both. Recordings and photographs have been forwarded to PACOM ELINT Center. On 3 August the ECM equipment on the Maddox lost its sensitivity and was of use only for strong signals during the remainder of the patrol. The Elint capability of both ships was noticeably hampered by the lack of D/F capability below 300 mcs. Most Communist Bloc Early Warning radars are below 300 mcs.

11. Communications.

a. Fleet broadcast reception during the July-August DESOTO patrol was satisfactory. Frequent frequency changes were necessary and both KWR-37s' and teleprinters were used continuously to maintain reception.

A wide variety of frequencies were copied from Guam, Japan, and the Philippines with good results. No particular frequency or frequencies can be recommended which will ensure thorough coverage. Constant attention was given to monitoring frequencies and shifting as conditions warranted.

b. Due to the fleet broadcast equipment requirement, Duplex Radio Teletype would have had to utilize a transmitter distributor only for transmission and a typing reperforator for reception. This would have congested the teletype room with operating personnel. As an alternate, the Naval Communications Station, Philippines, provided a special CW circuit for the DESOTO units. Various frequencies were assigned in the A2 series by NAVCOMMSTAPHIL and excellent communications were maintained during the entire period. Traffic moved quickly and efficiently on this circuit and communications were never lost. The traffic sent on this circuit appeared on the fleet broadcast, where necessary, in a very short period of time thereby indicating expeditious handling by NAVCOMMSTAPHIL.

c. Communications on the HICOM circuit were sporadic and generally nonexistent late at night. Radio checks were attempted every four hours. The Maddox was able to complete communication checks with CTG 77.6 at Hong Kong throughout the day, but no contact was made on the HICOM circuit with CTG 77.5. In order to maintain the required communications with CTG 77.5, the equipment used on HICOM (URC-32) was shifted to TG 77.5 CID net with good results. Communications thereafter on this circuit were generally satisfactory.

d. The outgoing encrypted traffic load was extremely heavy during the patrol. In seven days, 76 off-line messages were encrypted. All messages, with the exception of flash precedence, were check decrypted by a different cryptographer prior to transmission. Flash precedence traffic was check decrypted immediately following transmission.

A well trained Crypto Board, including sufficient personnel trained in limited access key list procedures, is an absolute requirement.

It is recommended that a spare crypto machine be drawn from RPIO prior to departure for patrol.

12. Photography.

a. VOBRAK, J.W., 539 59 12, PH3, USN, from the Pacific Fleet Mobile Photographic Unit, Detachment "A", was embarked during the patrol and was assigned the responsibility of photographing surface and air targets of opportunity. VOBRAK used a NIKON F SLR with two lenses; a 135 MM and a 500 MM. Sixteen rolls of film were exposed yielding approximately 261 pictures. The majority of the exposures were of the coastline with several shots of possible ECM sites, of small fishing boats, and of the torpedo boat attack on 2 August. Photographic conditions were generally poor due to haze.

b. ECHERSLAY, W. W., 587 64 94, RD3, USN, from the USS Ticonderoga (CVA 14) took radarscope photographs of land masses in the vicinity of the patrol track. A CRZ-6 radarscope camera was utilized. Ten feet of film were exposed which should yield 120 pictures of the coastline. Pictures were taken every five miles along the coastline. At river mouths several exposures were made varying the scope gain for greater detail. Conditions were excellent for this type of photography due primarily to the performance of the AN/SPA-8A radar repeater. The pictures taken should produce very good coverage of the coastline.

Enclosure (8) is a detailed log of the exposures made during the patrol. The undeveloped film is forwarded with this letter for disposition by CTF 72.

13. Hydrographic and Bathythermograph Data.

a. Forty-seven BT drops were made and continuous soundings and associated fixes were obtained every 15 minutes from 31 July until the afternoon of 2 August.

b. Navigational aids sighted/verified:

(1) CUA TUNG RIVER -- Steady white light, visible 10 miles, right side of entrance; 17-01.1N 107-03.7E. (see chart H. O. 6211)

(2) ILE du TIGRE -- No navigation lights; conspicuous tower on summit; 17-09.6N 107-20E. The southwestern side of the island has two sandy beaches suitable for LCVP or LCM dry ramp landings. (see chart H. O. 6211)

(3) HON ME -- Very bright white light (mercury vapor or xenon), 1 second flashing over dim steady white light; 19-21.9N 105-55.6E. Excellent NavAid when in operation but it is believed that its operation is controlled by the military and it does not operate continuously. (see chart H. O. 2594 or 6214)

(4) BEN SON light -- Has been extinguished; 19-20.3N 105-49.2E. (see charts H. O. 2594 and 6214)

(5) CUA HOI entrance lights -- Extinguished; 18-45.5N 195-45E. (see chart H. O. 6214 or 2596)

(6) HON MATT to HON ME -- There are many fish trap markers between these islands, extending seaward to 106-15E. The markers consist of clusters of two to four bamboo poles sticking five to ten feet above the surface, either erect or at some grotesque angle. (see chart H. O. 6214)

(7) General comment-- Permanent lighthouses and beacon structures were noticed on the coastal promontories and off shore islands between 17 N and 19-30N. None of these lights were observed to be in operation.

c. Sailing Directions, H. O. Pub. 93 was found to be generally accurate in the area covered. In some cases difficulty was experienced in locating places described in H. O. 93 on the chart since different proper names were listed. It is recommended that future changes in the publication or in the charts bring the names into agreement.

14. Navigation. The primary means of navigation while on the track and when orbiting were by visual bearings during daylight and by radar at night. No dependable navigation lights were available. Loran and DRT were utilized during night retirement in the central area of the Gulf. Loran stations 1L6, 1L7, 2H3 and 2H4 were satisfactory at night, and 1L6 and 1L7 were satisfactory during the day. The sketches of landfalls found in the Sailing Directions (H. O. 93) were of little value since the tracks were 8 to 16 miles off the coast.

15. Recommendations.

a. That positive action be initiated to ensure that the AN/SLA-2 Pulse Analyzers in Yokosuka are operable prior to issue.

b. That berth 17 or 18 be used by DESOTO units instead of berth 1-B, which is difficult to get away from with an onsetting wind. Berths 17 and 18 or alongside the AO at berth 13 are excellent. All three berths are military controlled, and these piers are patrolled by GRC sentries.

c. That a qualified radarscope photographer and radarscope camera be made available from a more permanent source than from a CVA at the last minute. A photographer need not be provided if a complete briefing is provided for scope photography, including temporary issuance of NAVAER 10-1RH-512b (Photography Technical Bulletin – Radar Scope).

d. That a Lloyd's of London Ship Register be made a part of the DESOTO turnover file.

e. That fuel requirements of the patrol ship be carefully considered in planning the patrol.

f. That ECM equipment with D/F capability below 300 mcs presently used by reconnaissance aircraft be made available to DESOTO ships.

g. That a detailed ELINT briefing be provided to at least the CIC watch officers and supervisors while in port.

h. That ships with on-line encryption capability be assigned DESOTO patrols if they are available.

16. Summary.

a. Intelligence collection was limited to that area between points "A" and "D" before the patrol was interrupted on 2 August. After 2 August the patrol continued in waters already covered and very little additional information was collected. Fishing in the patrol area virtually ceased by 8 August.

b. ELINT confirmed several known radar sites. Of more than general interest was the intercept of an unknown signal resembling an Early Morning radar with possible MTI and also the visual sighting of a probable DF site similar to but smaller than a THICK EIGHT, located on NUI TRUONG Point. Neither BKDQ nor BKEH signals were detected. The Maddox was not equipped to detect or locate sources of 10-50 KC emissions. Many towers were sighted along the coast indicating complete radio communications coverage.

c. The only ships noted in the area were two coastal type vessels probably used in replenishing HON ME. One merchant man was sighted en route from Haiphong to Penang. A total of five patrol craft were sighted, three P-4 and two Swatow. There was no apparent pattern evident in the movement of the junk force.

d. The assistance given by the Naval Security Group detachment, LT Gerald MOORE, USN, Officer in Charge, proved to be invaluable. The Detachment is being commended.


Copy to:
CINCPAC (less encl (10))
COMNAVFORJAPAN (less encl (10))
COMCRUDESGRU 7th FLT (less encl (10))
CTG 72.1 DESOTO File (less encl (10))
CNO (OP-922) (advance copy)
FIRST RADIO BN, FMFPAC (Attn: LT SANTOS (less encl (10))

Source: Tonkin Gulf Collection, 1962-1984 [1964 and 1968], Series I: Misc. Subject Files, 1964, Box 1 of 12, Operational Archives Branch, Washington, DC.

05 July 2006