Station HYPO

In late 1961–early 1962 a series of U.S. Navy patrols off the east coast of Communist China was proposed. The purpose of these patrols was to be three-fold. In the first place they would establish and maintain the presence of the U.S. Seventh Fleet in the international waters off the China coast; second, they would serve as a minor Cold War irritant to the “Chicoms”; and third, they would collect as much intelligence as possible concerning Chicom electronic and naval activity.

The initial phasing called for one U.S. destroyer to conduct each mission. There would be three installed positions on each mission (two radio telephone and one manual Morse), and these positions were to serve a dual role-provide direct SIGINT support to the defense of the ship, and serve as intelligence collection facilities for as many different sources and categories of emission as could be obtained. These patrols were given the cover name DESOTO.

From 14 to 20 April 1962 the first DESOTO patrol was conducted, with the destroyer USS DE HAVEN as the participating vessel. The area of responsibility encompassed by the mission focused around the Tsingtao area of the Yellow Sea, and the ship was instructed not to approach any Chicom-held territory, including the offshore islands, closer than 10 miles.

Major intelligence targets for this mission fell into five categories: Chicom naval units, particularly submarines; ELINT of Chicom electrical installations; Chicom air activity; hydrographic and weather information; and merchant shipping (particularly Chicom) in the area. This first DESOTO patrol was singularly effective in evoking Chicom reaction. Such things as shadowing of the DE HAVEN by three or more Chicom vessels at one time, jamming of the DE HAVEN communications facilities and the use of deceptive pennant numbers on the shadowing vessels all contributed to the success of the intelligence effort on this mission. In addition, the Chicoms issued three “serious warnings” to the DE HAVEN for violation of territorial rights during the 7 days the mission was in progress.

For the remainder of 1962, eight more DESOTO patrols were run, and prior to December of that year, these patrols were all conducted in the East and North China areas as well as up the Korean coast to the Soviet Gulf of Tartary. After the first mission, intelligence derived from the patrols was quite sparse. Shadowing of the patrol vessels was noted, and serious warnings were issued to almost all the patrols by the Chinese Government, but unique information was virtually nil.

In December 1962, with DESOTO patrol number IX, the USS AGERHOLM conducted the first probe into South China waters and the Gulf of Tonkin around Hainan Island. This pattern was repeated in April 1963 when the USS EDWARDS traversed the same path around Hainan Island and then extended its mission down the coast of the Democratic Republic of Vietnam (DRV). No DRV reflections were recorded at this time, and Chicom reaction was again limited to shadowing and issuance of serious warnings. Since serious warnings were not reserved for DESOTO missions (at that time the U.S. had received over 350 of these warnings for both air and sea violations), no particular significance could be attached to them.

The first DVR reaction to a DESOTO patrol came in late February–early March 1964 on the third venture into the Gulf of Tonkin, this time by the USS CRAIG. DVR radar stations performed extensive tracking of the CRAIG on her first run up the coast, and DRV naval communications referred to the CRAIG by hull number on one occasion. Although intelligence collected from this mission was not voluminous, it did contribute new insight into the placement and capability of DRV tracking stations and equipment.

Prelude to Violence

The fourth DESOTO patrol into the international waters of the Gulf of Tonkin was programmed in July 1964. Concerned more with the Vietnamese problem than the Chicom problem of its predecessors, this mission was to observe the junk fleet vessels believed to be a constant source of resupply to the guerrillas in the south, obtain navigational and hydrographic information, and procure any available intelligence on the DRV navy. Since the 1954 Geneva agreements specifically prohibited the DRV from establishing a navy, the emergence of this force had been, until late 1963–early 1964, extremely covert. During late 1957 the first DRV naval communications facilities were isolated with an estimated 30 ships involved in the transmissions. Then in 1959 the first evidence of the emergence of a modern DRV navy was noted during a probable joint DRV/Chicom naval exercise in the Pearl River estuary. Some of the vessels involved in this exercise were believed to be the same 10 motor gunboats later noted passing through the Hainan Strait, and probably represented the DRV’s initial acquisition of modern naval craft. Augmentation of this force was continual after 1959, and as of late 1964 the DRV navy had a total complement of nearly 100 vessels. –

Armed with this background, and clear on the purpose of the mission, the USS MADDOX reached a point on the 17th parallel about 12 miles off the coast of the DRV on 31 July 1964 at 1300 hours local time. From that point the MADDOX turned northward on a tack that was to take her up the coast for three days in what was believed to be another routine running of a DESOTO patrol.

Confrontation

Apparently the MADOX was not the only vessel active off the North Vietnamese coast on the night of July 31.  DRV naval communications reflected that on that date the “enemy” had fired upon the island of Hon Me, and had been pursued by DRV warships to no avail.  The MADDOX reported sighting vessels being pursued by DRV patrol craft, but had made no attempt to investigate the action.

Whether or not an association between the above-mentioned attack and the presence of the MADOX was drawn by the DRV is impossible to say.  They did protest to the International Control Commission that “American imperialists” has shelled their fortifications, but that was a constant complaint of the DRV and could not be directly attributed to the presence of the MADDOX when they mentioned that the “enemy” was “going on a course of 52 degrees . . . 9 nautical -miles from Hon Me . . . “

Shortly after placement of the MADDOX near Hon Me Island by DVR tracking authorities, – a message was passed to an unidentified DRV : fighting vessel stating that it had been “decided ~to fight the enemy tonight.” The MADDOX was apprised accordingly in a warning which preceded the actual attack by more than 12 hours.

DRV naval tracking stations were observed in continual surveillance from that time on. In addition, several messages were intercepted, apparently pre-positioning warships in preparation for the attack.

Between approximately 1130 and 1215 (Saigon local time) on 2 August, the MADDOX reported sighting three PT’s and two probable SWATOW class PGM’s (motor gunboats) about 10 miles north of Hon Me Island. During the same time frame the MADDOX reached the northernmost point of its mission and observed a large junk fleet (approximately 7S craft), which it intended to avoid on its return route. There were no military ships intermingled with the junks, and there was still no apparent hostility.

It is not possible to ascertain exactly which element of the DRV naval command ordered the attack, but shortly after the MADDOX reached the apex of its mission, a message was passed stating that it was time to close with the “enemy” and use torpedoes. The MADDOX received this information some 50 minutes before the aggressive actions commenced.

At 1530, some 30 miles from shore, the MADDOX altered her course to the southeast, heading for the mouth of the Tonkin Gulf, and increased her speed to 25 knots, attempting to avoid the three DRV torpedo boats reflected on radar as closing at about 50 knots, within 20 miles of the DESOTO ship.  At that time the MADDOX requested air support and posted all hands at their battle stations.

By 1600 the DRV boats were within 5 miles of the MADDOX, still traveling at about 50 knots, and had moved into column formation, an accepted procedure for torpedo assault.  The MADDOX fired three warning rounds across the bow of the lead ship, but for naught; and at 7 minutes past the hour, the MADDOX reported that she was under attack.

The PT boats broke into two formations as they closed on the stern of the MADOX, with two of them approaching from the right side and one from the left. At a range of 2700 yards the two PT’s on the right each launched one torpedo. The MADDOX then turned to the left to avoid the torpedoes, keeping the attacking craft under fire, and scored a direct hit on the PT approaching from the left, just as that craft placed a torpedo in the water. The torpedo did not run.  Air support from the TICONDEROGA arrived at that point and engaged the attacking vessels, and the MADDOX withdrew from the area. Total damage: one ORV PT boat dead and burning in the water; extensive but not totally disabling damage to the other two PT’s; and slight damage to one gun on the MADDOX.

In order to assert the right of the U.S. to freedom on the seas, it was decided that the DESOTO patrol should be resumed as soon as possible. The strength of the patrol was doubled, with the USS TURNER JOY joining the MADDOX for a proposed four-day continuation of the mission; a formal warning was issued to the ORV authorities in Hanoi, stating that any further such unprovoked actions would result in severe retribution; and at 0900 on 3 August, the DESOTO mission was resumed. For this phase, continuous combat air support was provided.

During the day of the 3rd, the MADDOX reported that both she and the TURNER JOY had picked up radar signals and believed they both were being shadowed. This same suspect shadow activity occurred during the daylight hours on 4 August, but there were no provocations. Then the DRV naval communications facilities were observed alerting two SWATOW-class PGM’s to make ready for military operations on the night of the 4th. The DESOTO units were advised of the possible attack, and headed for the mouth of the Gulf “at best speed.”

The MADDOX reported several radar sightings of apparent hostile craft throughout the early evening hours of 4 August. Some of these sightings later broke away, but some of them continued to close. At about 2200, the MADDOX reported firing on an attacking PT boat which had presumably launched a torpedo. Three more probable PT’s were tracked closing rapidly on the DESOTO ships, and continual torpedo attack was reported through 0035 on 5 August. During the attack period the two DESOTO vessels engaged several radar contacts, and the TURNER JOY reported that one vessel was probably sunk. It was also reported that a ORV PT boat may have sunk one of its own companions in the conflict.

The weather throughout the attack was overcast and cloudy, thus impairing the visibility of the support air fighters and making it impossible for them to sight the assailants. The DESOTO patrol initially reported that at least 21 torpedoes were launched during the battle. This figure was viewed as highly unlikely since the PT’s carried only two torpedoes each, with no known on-sea reload capability, and the total DRV PT force was estimated at around 13, three of which had been damaged in the fighting of the 2nd. The figure was later amended when it was determined that the sonar operators may have seen their own propeller beats reflecting off the rudders during the zigzagging evasive action followed by the two DESOTO ships.

In retaliation for this second hostile action, JCS ordered CINCPAC to conduct a onetime maximum effort air strike against selected DRV targets, to include several ports known to house SWATOW-class PGM’s and PT’s, as well as a “priority one” hit on the Vinh oil storage area. This strike commenced on 5 August at 0700 and resulted in an estimated 90% destruction of the Vinh oil storage area plus total or partial destruction of approximately 29 DRV naval vessels.  The U.S. lost two aircraft in the 64 sorties that were flown, and suffered severe damage to a third. In addition, one U.S. pilot was killed and another was captured.

The MADDOX and the TURNER JOY resumed the DESOTO mission of 6 August without further incident, and the rest is just painful history.

By Walter D. Abbot, Jr

Source: NSA/CRYPTOLOG February – March 1975