Operation 34A and the Nasty Class PT Boats


This is the inside story of Operation 34A and the Nasty Class PT Boats – and the crews that manned them during the Vietnam War.
By Jack H. Jennings and Tran Do Cam

Most Americans consider that our involvement in the Vietnamese War began with the Tonkin Gulf incident. The fact is our involvement began almost immediately following the 1954 Geneva Peace Accords that divided the country at the 17th parallel. The Pentagon Papers leaked some information, but the whole story of this operation is only now becoming known. Immediately following the Accords, CIA Director Allen Dulles sent Air Force Colonel Edward Lansdale to Vietnam as Deputy Director of the Office of Special Operation with orders to implement clandestine operations against the North. Highly experienced in such operations, in the 1950’s Lansdale performed similar duties for President Magasasay eliminating the Philippines of Huk Communists.

Lansdale recruited and trained Vietnamese civilians to carry out the initial counterinsurgency operations against North Vietnam. Lansdale relied on a variety of ethnic Vietnamese crews to accomplish this mission including Nung and other minorities that came from areas close to the Chinese border. For security reasons, Lansdale used Saipan as a training center. Later, the CIA borrowed trained counterinsurgency operatives from Taiwan for commando raids into North Vietnam. Early operations used native junks since they blended into the fishing boats off the North Vietnamese waters. These operations continued over the years, some highly successful while others were less so resulting in the complete loss of some crews. The code name for these operations was Nautilus after the mysterious submarine from Jules Verne’s 20,000 Leagues Under The Sea. Missions consisted of inserting spies recruited by the CIA and commando raids conducted by Republic of Vietnam frogmen. As the NVN Navy improved intelligence gathering capabilities, the routes used by Nautilus missions became well known and the junks soon lost their advantage of blending in. The NVN simply waited for the junks to cross the 17th parallel. The junk’s slow speed and weak firepower became too much of a disadvantage against North Vietnam’s heavily armed Swatow and P-4 gunboats.

In July 1962, the CIA and the Department of Defense determined that the CIA did not have the operational capability and capacity to effectively carry out the mission and determined that the DOD should have operational control. Admiral Harry Flelt, Commander in Chief, Pacific, analyzed the situation and recommended that PT Boats and Frogmen be used to carry out the mission. President Kennedy, himself a WWII PT Boat commander, liked the idea and approved its immediate implementation. On January 1, 1963, the Military Assistance Command, Vietnam Special Operations Group (MACV-SOG) assumed the responsibility for operations.

Operations Plan 34A

In May 1963, the Joint Chiefs of Staff directed Admiral Flelt to prepare a plan to support the RVN Navy effort to carry out special operations in North Vietnam. On August 14th, the JCS approved the final plan that became OPLAN 34-63. Slight adjustments were again made and approved on September 9, 1963. Before fully implemented, a coup d’état against President Ngo Dinh Diem took place on November 3, 1963. Despite the command confusion, commando raids continued under OPLAN 34-63. By December 1963, MACV-SOG became disappointed with performance and sought ARVN military participation. A new plan, known as OPLAN 34A was prepared that included ARVN with U. S. Navy support and was approved by JCS on December 15, 1963. Secretary of Defense McNamara and President Johnson wanted to deliver a strong message to North Vietnam that the U. S. would not accept the Communist invasion of the RVN. The main objective was to combine the attacks against the North with Diplomatic pressure to warn the North to cease their infiltration in Laos and RVN. Thus, the United States entered into a new phase of the clandestine operations against the North.

To support this operation, the U. S. Navy set up a base in Danang consisting of SEALS, U. S. Marine intelligence officers, and other specialists experienced in guerrilla operations. Two PT Boat crews along with necessary maintenance crews were sent to train Vietnamese crews in PT Boat operations and methods to use them in commando raids. On January 21, 1964, JCS approved the implementation of the first phase of OPLAN 34A. The maritime section of OPLAN 34A had the main objective of conducting operations on the sea routes and to engage in psychological warfare against North Vietnam. The JCS maintained tight control over operational planning leaving the details of completing the plan to MACV-SOG personnel.

The organizational structure that specialized in running the coastal commando operations consisted of the Vietnamese Navy Coastal Security Service comprised of VN SEALS and Boat Crews and technical specialists. All Vietnamese SEAL Teams and Boat Crews were recruited from the brightest and best of the VN Navy with superior service records. In addition, a small number of VN Army specialists were recruited and trained in SEAL tactics. The junks were rapidly replaced with NASTY class PT Boats. At that time, the NASTY was considered the best and most modern PT Boat in the world.

Tonkin Gulf Incident

By early 1964, operations using the newly arrived PT Boats were in full swing with excellent success. On July 30, 1964, impressed with the operational success, the JCS ordered to triple
the August schedule over that of July. This was a six-fold increase over the June schedule. On the night of July 30, the more aggressive schedule involved a nighttime raid on Hon Me and Hon Nieu islands off Thanh Hoa coast. This was a four boats raid involving PTF-2, PTF-3, PTF-5, and PTF-6. (PTF-2 was one of the gasoline-powered boats; the others were NASTY’s). At midnight, the four boats split up and headed for their respective objectives. At Hon Me, a fuselage of heavy machine-gun bullets met PTF-3 and PTF-6 causing heavy damage to the bow of PTF-6 and wounding four crewmen. Suddenly, a crewman sighted a Swatow patrol boat mooring near the island. With insufficient time to get a SEAL team ashore to blow up the target, the crew blasted a water tower and several military buildings with 40 mm and 20 mm gunfire. Caught in the glare of an illumination flare fired by the Swatow, the PTF’s continued to pour fire into the targets. In less than 25 minutes, the attack was over. It was now thirty minutes into August 1, 1964. Both boats sped away at 55 knots, easily outdistancing the Swatow only making about 45 knots.

At Hon Niew, PTF-2 and PTF-5 had better luck. They approached unnoticed and hammered a communications tower silhouetted in the moonlight. Only light machine gun fire was returned with no damage. After forty-five minutes of pounding the tower and other targets, both boats raced back to Danang. North Vietnam lodged a complaint with the International Control Commission. The United States denied involvement. In response, the North Vietnamese commenced a buildup of their naval presence and shifted about one-third of their 50 P-4 and Swatow gunboats from Haiphong to that area. General Westmoreland recognized that the successful 34A operations were responsible for this response.

At about the same time as the implementation of OPLAN 34A, the Navy began Desoto patrols along the coast that were designed to eavesdrop on communications from North Vietnam. These patrols were conducted by American tin cans that were careful to stay in International Waters, at least four miles off shore in the case of North Vietnam. General Westmoreland and Admiral Sharp, Pacific Fleet Commander-in-Chief, had discussed using the Desoto patrols to assist in the direct conduct of 34A operations, however, this was abandoned to preserve the plausible deniability of U. S. involvement. Nevertheless, in July 1964, Westmoreland had requested that Desoto monitor the upcoming 34A operations in case they were needed for support. Two days following the attacks on Hon Niew and Hon Me, at 1600 on August 2, frustrated with its inability to interdict the Nasty boats, North Vietnamese launched a torpedo attack against USS Maddox (DD-731) using four Soviet torpedo boats. Maddox, supported by aircraft from USS Ticonderoga (CVA-14), shot up the attacking boats leaving one boat dead in the water. The battle was over in 22 minutes. Maddox took machinegun rounds from a North Vietnamese PT boat, but steamed out of the area without further damage and no loss of life. The North Vietnamese had naturally connected the Desoto destroyers with the events of late July and early August since Maddox was steaming off the coast of Hon Me island at the time.

Undeterred by the events of August 2, the maritime operations from Danang launched a four boat 34A operation on August 3. The objective was to bombard a radar station at Vinh Son and a security post on the banks of the Ron River; both about 90 miles north of the 17th parallel. PTF-1, PTF-2, PTF-5, and PTF6 were the boats involved. After a successful attack, the PT Boats kicked into flank speed of 50-plus knots easily outdistancing pursuing enemy Swatows. Knocking out the radar station blinded North Vietnam contributing to their confusion.

On August 4, Maddox and USS Turner Joy (DD-951) reported that they were involved in an attack. The next day, on 5 August, planes from Ticonderoga and USS Constellation (CVA-64) struck an oil storage site in North Vietnam and destroyed coastal vessels. On 7 August, the U. S. Congress passed the Tonkin Gulf Resolution with overwhelming support. Now it is well known that the August 4 attack did not actually occur. This series of events permanently disrupted attempts by President Johnson to send a message to the North Vietnamese government through the Canadian delegation to stop its war against the South, thus setting the course of action for the next ten years.

The ICC immediately headed for Danang to investigate the PT Boat base. In the meantime, the Navy relocated the PT boats south to Cam Ranh Bay where they lay low until the ICC investigation was over; a week later they were back in Danang the crew having spent the week camping out on a small pier. Back in Washington, President Johnson ordered a halt in 34A operations to avoid any ambiguous message. By now, the veil of secrecy as to the location of the PT Boats was thin. Ambassador Maxwell Taylor, in Saigon, objected to the halt of operations. Following the Tonkin Gulf Resolution, the attacks again commenced in earnest.

Why the NASTY Class PT Boat

The search for a boat dates back to 1959 when the Navy was looking to replace the aging WWII torpedo boats. The top choice was the 80-foot Nasty Class patrol boat used with considerable success by the Norwegian Navy since 1957. Built in Norway, the boat had two British-built supercharged diesel engines delivering 3,100 shaft horsepower and could reach speeds of 44 knots fully loaded and speeds of over 50 knots after burning off some fuel. The cruising range could extend to about 1,000 miles at a speed of 20 knots. The Navy ordered 16 NASTY class boats and classified them as Patrol Torpedo, Fast, or PTF.

To fill in the demand before the NASTY’s arrived, Navy planners found two old WWII vintage PT Boats build in 1950. These boats were powered by Packard engines running on gasoline but proved unreliable in this mission due to engine problems and noise. In fact, the engines were difficult to start at times: this proved to be a serious weakness when on an insertion into North Vietnam waters when suddenly surprised by a Russian made P-4 or Swatow patrol boat. By the end of 1965, when enough NASTY’s became available, the gasoline boats were replaced and used for target practice.

The firepower of the NASTY was significant consisting of a 40 mm gun on the aft deck and two 20 mm guns, one on the port and one on the starboard side. An 81 mm mortar with a 50 caliber machine gun mounted piggyback was placed forward of the bridge. On some missions, the crews carried a 57-mm recoilless rifle for additional firepower.

In total, 16 NASTY boats saw service in Vietnam. As the demand for 34A operations increased and some were lost in action, an American company, Trumpy Boat Company, commenced building a knock-off of the NASTY called Osprey. The Osprey’s were of aluminum construction while the NASTY’s were laminated wood. The flexibility of the wooden construction actually proved to be superior and some of the Osprey design developed stress cracks in battle conditions and at flank speed in rough seas.

Action North

Many of the missions north of the 17th were simply milk runs with a continuous threat of meeting up with shore bombardment, attack by air or an attack by P-4 or Swatow gunboats. In addition, the North Vietnamese sometimes used suicide junks to try to sink a NASTY. During the length of the Vietnamese war, only one boat was lost to direct enemy action when a North Vietnamese bi-plane dropped a homemade bomb that unluckily hit PTF-9 on the fantail flooding the engine room. Other boats were lost when they ran aground racing south following an attack or while being chased by an enemy gunboat.

Direct action against the Russian made P-4 and Swatow gunboats was always one-sided. The NASTY was a superior boat with superior crews and superior firepower. In most cases, the North Vietnamese simply avoided direct combat or faked engine trouble to avoid a fight, or they radioed back that the NASTY was pulling away out of gunfire range. The after-action report by some aggressive NASTY officers sets the tone for the entire war:

On the night of February 19-20, 1971, four PTF’s were near the island Hon Niew observing and photographing Chinese shipping. Suddenly the boats were attacked by a North Vietnamese P-4, which was engaged and easily sunk. Mission compromised; the four PTF’s headed south and within an hour were engaged by a P-4 and a Swatow. The PTF’s left the attacking boats heavily damaged and continued south. Between Hon Gio Island and the coast, a P-4 torpedo boat and a Shanghai class gunboat again attacked them. The PTF’s left the attacking boats damaged and speed back to Danang at 55 knots, undamaged and with one KIA. During the duration of OPLAN 34A, the NASTY’s sank the majority of the P-4 boats.


OPLAN 34A missions were of a strategic nature primarily involving clandestine psychological warfare and secondarily commando raids to destroy military targets. Psychological operations included tax extraction from fishing boats, propaganda distribution using the 81-mm mortar and other operations creating havoc behind enemy lines. Some included taking snatches that were taken to Cu Lao Cham Island offshore from Danang were they were well fed and led to believe that they actually lived in a secret liberation zone of the Sacred Sword of Patriotic League located in North Vietnam. Later taken back to the north, plump and well fed, with the expectation that they would spread the story of the lifestyle outside of communism. Most of the psychological operations occurred north of the 18th parallel in more densely populated areas. Additionally, psyc-operations included dropping radios with a fixed frequency set on a CIA run station.

Vietnamese SEAL teams conducted raids and shore bombardment mission designed to destroy specific targets and to extract snatches. Military snatches in these missions were also carried to an offshore island for interrogation and perhaps reeducation. The following first-hand account describes the typical psychological operation:

“During 1967, we undertook a special psychological warfare program. We captured more than 300 fishermen in a three-month period. We took two individuals from every village. After delivering them to Cu Lao Cham we made sure that they were well fed. Each person ate a half chicken every day and after three months, was plump and had a healthy complexion. We took each back to their hometown to see what the reaction would be both locally and to the regime. It came as no surprise to us during the next six months that when we tried to capture the same individuals, they were nowhere to be found. After almost nine months had passed, we finally captured one fellow who signed: ‘You folks hurt us. When you released us, the local government officials noticed that we were fat so they put us in the thought reform camps and just released us.”


The Vietnamese Navy recruited boat officers from the most motivated and highest ranked graduates of the Naval Academy. Likewise, boat crews came from the most capable and experienced seamen. Motivation and espri-de-corps were always high among the crews and MACV-SOG maintained morale by supplementing their pay with an extra payment for each trip north and with special rations. As an example of the high morale, crewmen always volunteered for difficult missions in addition to their own schedules. There were rumors that American personnel were on board PTF’s on missions to the north. This is not true, at least during the period from 1965 to 1970 when the authors were with the PTF’s in Danang.

Over the roughly eight years in operation, OPLAN 34A sent over 1,000 missions into waters off North Vietnam. Nearly all missions were successful and achieved their primary or secondary objective. Few were complete bust, and none failed because of poor leadership or lack of skill. As an example of leadership and seamanship, the Vietnamese crews lost less than 40 casualties out of the thousands of individual missions. The single worst skirmish was a blue-on-blue event with one boat loosing two officers. Clearly, the crews that manned the NASTY’s were the best that Vietnam had to offer and they lived up to the highest standards.

  • Jack Jennings served with Boat Support Unit 1 during 1965-1966. He now resides in Dallas Texas and can be reached by E-mail at Jack@Jennings.net
  • Tran Do Cam served for five years as Executive Officer and Commanding Officer of PTF’s. He now resides in Austin Texas and can be reached by E-mail at DoCam11@yahoo.com