Operation JACKSTAY: March/April 1966
Before describing the various task forces' contributions to riverine warfare we might note Operation JACKSTAY, late March, early April, 1966--a full-scale U.S. Naval amphibious operation launched from a "blue water" force off the coast.
Operation JACKSTAY was an amphibious operation, launched from the USS Princeton (and the USS Alamo – JL), that utilized surface borne and helicopter borne assault forces. D-day for this search and destroy mission: 26 March 1966 . The scheme of maneuver dictated two phases over a period of about ten days. 1/5 landed and spent almost two weeks in the swamps of the Rung Sat Special Zone, a swampy area intersected by waterways, during Operation JACKSTAY.
Phase one began 26 March 1966 as a surface/helicopter amphibious assault on the face of the Long Thanh Peninsula by Marines of the 1st Battalion, 5th Regiment. Underwater Demolition Team (UDT) swimmers, preparatory air strikes by Seventh Fleet carrier-based aircraft and naval gunfire all supported the operation. Throughout, amphibious craft and coastal surveillance craft provided blocking and surveillance against Viet Cong escape. The long inland reach of sea power swiftly adapts to complex needs.
The second phase, a deep penetration of the swamps, began 31 March as an 18-boat convoy entered the Vam Sat River. Led by two French-built, Vietnamese-manned FOMs (a V-bottomed boat about the size of an LCVP), the convoy included two Vietnamese LCCPs rigged with chain drags and grapnels for minesweeping; a Vietnamese Monitor (an armored LCM-6 with a mortar and automatic weapons); seven LCMs and two LCVPs carrying U.S. Marines; two LCPLs providing additional gunfire support; and two U.S. Navy LCM-3 salvage boats. Throughout the 7-mile transit down the Vam Sat, carrier-based aircraft and armed helicopters provided air cover. Commander Derwin T. Lamb, USN, directed the operation from the open deck of an LCPL positioned directly behind the Vietnamese "minesweepers" and ahead of the Marines. The overall commander of the operation, Captain John D. Westervelt, USN, rode a helicopter patrolling overhead.
As the group approached the first bend of the Vam Sat, the Viet Cong tripped a crude electrical mine halfway between Lamb's command LCPL and the Monitor--a booming echo of Confederate "torpedoes" a century ago. The Navy craft escaped damage, however, because they had wisely hugged the shallow side of the river instead of navigating center channel. Following the mine blast, intense small arms fire burst from the matted foliage on both banks. Driving on through enemy shots, the boats opened up with everything they had--40-mm guns on the Monitor, .30-caliber guns on the LCPL, and small arms fire from the troops in the LCMs. Meanwhile, aircraft bombed and strafed guerrilla positions about 100 yards inland, preventing the Viet Cong from bringing heavy guns to bear. About a mile down river, the enemy fire lifted, and the rest of the passage was marked only by sporadic sniping.
After landing troops in the heart of the dismal mangrove swamps, the convoy moved back up river in the same formation to embark two companies of Marines working their way through the swamp to a predetermined point. The pickup was without incident; one observer reported:
The mike boats [LCMs] churned up to the shore, crashing their way through the overhanding tree limbs and dense undergrowth along the swampy edge. And as the ramps of the mike boats were lowered, they cut an opening right through the rotted vegetation, making it easier for the Marines to come on board.
As the convoy moved ahead after picking up their Marines, they again ran into small arms fire, which continued for the greater part of the trip upriver. The open LCMs, each carrying 60 Marines, were vulnerable targets. Close air support was especially helpful. Bombing and strafing on either side of the river again prevented the Viet Cong from bringing up heavy weapons or concentrating small arms fire. As the firing slowed, then silenced, the convoy moved out into open water of the Soi Rap.
As planned, on 6 April 1966 , the Marines of 1/5 withdrew from the Rung Sat Special Zone and went back aboard the USS Princeton (and the USS Alamo - JL). According to the Combat After-Action Report for Operation JACKSTAY, compiled by Lt. Col. Coffman, CO of 1/5, at least 63 Viet Cong were killed by 1/5 Marines and probably 60 more were either killed or wounded. In addition, a substantial amount of enemy equipment and material was captured and/or destroyed by BLT 1/5. Overall, the Marines of 1/5 had accomplished their mission with great success, while taking very few casualties. The Rung Sat Special Zone turned out to be a very difficult area to conduct combat operations, but the Marines were up to the task.became increasingly involved in the river war.
JACKSTAY pointed up the versatility made possible by control of the water whether offshore or within a country. The operation, conducted in two phases, was planned to decimate the Viet Cong in the RSSZ. These 400 square miles of swamp, thickly covered by tropical vegetation, are particularly suited to clandestine operations. For a generation the region had harbored the Viet Cong, with their arms factories, recuperation, and training camps.
The results of JACKSTAY were more impressive than the 53 confirmed Viet Cong dead or the tons of material destroyed or captured. They can be measured in terms of the penetration of sea power into the very heart of the enemy's sanctuary. As our initial major riverine operation, it proved what the enemy would soon learn more conclusively: that wherever water reached, there was no longer any sure place to hide from the versatile extension of the American Navy.1
1U.S. Navy. Naval History Division. Riverine Warfare: The U.S. Navy's Operations on Inland Waters. Washington, DC: U.S. Government Printing Office, 1969.
This is the official report of the Operation written by the Lt. Colonel commanding 1/5. That’s why so much mention is of “1/5” troops. I have added parenthetical enhancements through the body of this report to add the contribution of C Co., !st Tanks.
An addendum to this is that the blocking forces mentioned in “the second phase” were made up of crewmen and staff of Charlie Co., 1st Tank Battalion, which were on float with the USS Alamo along with the USS Princeton and others. The tanks (and some Amtraks which we picked up in Hawaii) were on the well deck. They were left on board while the rest of the Marines (mainly tankers and H&S co. staff) were off-loaded onto some Mike boats from the well deck and taken into shore. Somewhere in the Stars & Stripes archives there is a picture taken by one of their reporters of us all huddled together in that landing craft prior to getting to the beach. Our landing was unopposed and we didn’t have to do too much blocking. We got into a fire fight that first night ashore. If we weren’t fighting the VC we were fighting the mosquitoes. They were so big they had radar and landing lights. I grew up along the Gulf Coast but I have never seen mosquitoes like they have in the Delta.
While we were on shore playing John Wayne, the Alamo was going to refuel. In the course of refueling they collided with the refueling ship, the USS Kawanisi. There was a huge gash in the side of the Alamo, part of it through the side of the ship by my berth. (there are pictures of this at http://navy.memorieshop.com/Alongside/Alamo.html)
This necessitated a trip to Subic Bay over Palm Sunday weekend while the maintenance people welded a plate on the side and cut off my fresh air/sea view compartment. After that we stopped in Cam Ranh Bay while some more of our tankers (but again, “not tanks”) were ashore in another operation. This Delta region was so watery that tanks would have made no sense at all in there. I’m not sure of the operation’s name but it might have been Thomas Jefferson I. After that we went back to Subic to resupply then came back off the coast of Vietnam and offloaded the tanks and personnel to the beach at Chu Lai. That ended our “float” period.
The Mekong Delta divides into three rather distinct regions:
1.The Plain of Reeds, located west by north of Saigon, is a vast area of reeds and grass, which during flood season lies under 1 to 6 feet of water and looks like an immense shallow lake from the air.
2. The lower Mekong Delta with its great rice growing areas extends from northwest of Saigon to the dense forests of the southern and western Ca Mau Peninsula. The rice producing area holds most of the Delta population and until late 1968 was the scene of most U.S. Navy riverine operations. The forests of the Ca Mau Peninsula provided secure base areas for the Viet Cong until coastal surveillance and river assault craft with ground and air forces began to reestablish government authority.
3. The third and possibly most forbidding area is in the mangrove and nipa palm swamps at the mouths of the Mekong and in the adjacent Rung Sat (Forest of Assassins) Special Zone surrounding the main ship channel to Saigon. Like the Florida Everglades, the area consists of many meandering waterways through entangled trees, vines, exposed, roots, and heavy undergrowth. Tides in these waterways are so extreme that river flow often changes direction, and the foliage is commonly so thick that troops 3 feet apart lose sight of one another.
A French naval surgeon who participated in Delta operations in 1945-46 described its environmental rigors:
“Progress across rice paddies and mangrove thickets forced the men most of the time to struggle through water and mud. Frequent transshipments aboard LCVPs to cross river channels became exhausting; in fact, owing to the absence of roads, it was necessary to carry on one's back, not only a regular kit, but also all the ammunition and weapons, such as machine guns and mortars . . . and finally, for these drenched men, veritable hunks of ambulating mud, the leaden sun added to their torment.”
It is clear that projection of sea power into such an imposing riverine environment requires a major naval effort. On 1 April 1966, U.S. Naval Forces, Vietnam, Rear Admiral N.G. Ward, commanding, was established to consolidate the several U.S. Navy efforts already underway in Vietnam under a single service component of the U.S. Military Assistance Command, Vietnam. In addition to the support commands at Saigon and Danang, and Seabee construction efforts, the Naval Advisory Group, the Coastal Surveillance Force (TF-115), and the River Patrol Force (TF-116) were placed under the operational control of Commander U.S. Naval Forces, Vietnam (COMNAVFORV) at this time. Approximately a year later the first units of the Mobile Riverine Force (TF-117) were added to the resources of COMNAVFORV for the specific purpose of conducting combined riverine operations. In October 1968, Operation SEA LORDS (South East Asia Lake, Ocean, River, Delta Strategy) was initiated with the activation of the TF-194 designator in order to facilitate the coordinated and integrated employment of units from all three U.S. Navy task forces in riverine interdiction, strike, and pacification campaigns.