OPERATION JACKSTAY 

                            PROVIDED BY SHIPMATE ROGER J. CRAGG

 I was a deck officer on the Merrick from 6/65-11/66. The Merrick provided the LCMs and crews for the Marines during operation JACKSTAY. The following is information that I have about the operation that I participated in as a Boat Offier.  1/5 MARINES was a Marine Corps Unit as was SLF. Operation JACKSTAY began with an amphibious assualt on the Long Thanh peninsula by the US Marines BLT as part of the SLF.  At this time, the 1st Battalion, 5th Marines was the primary infantry component of the BLT. The RVN committed two Marine battalions.  In late Feb and early Mar. the VC had attacked two cargo ships on the shipping chanel to Saigon.  MACV requested that the SLF be used to clear their base area.  This operation, 39 miles southeast of Saigon in the Rung Sat Special Zone, was the southermost large-scale employment of U.S. forces in Vietnam up to that date.  It terminated on 6 April 1966.  The SLF claimed at least 63 enemy KIAs while suffering 5 US KIAs, 2 US MIAs and 25 US WIAs.



Beore 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 the first major U.S. naval operation in the river environment of the Rung Sat Special Zone (RSSZ). It marked a turning point in the unfolding saga of projection of U.S. sea power from the high seas and coastal waters into the waterways of the Delta. Prior to this, the U.S. Navy's participation in the river war was fairly well limited to inshore operations by "Swift" boats, small fast patrol craft (PCF) of the Coastal Surveillance Force, and the work of U.S. Navy advisors with the Vietnamese Navy River Assault Groups. After JACKSTAY" the beginning of River Patrol Force operations and establishment of U.S. Naval Forces, Vietnam, the U.S. Navy 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.

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.

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.


Amphibious Operations
Operation JACKSTAY
A major amphibious operation was launched on 26 March in the Rung Sat Special Zone by the Seventh Fleet's Special Landing Force, and other American and South Vietnamese units.

The Rung Sat Special Zone is ideally suited for the capabilities of the Navy-Marine team. It is largely inundated at high tide and its primary lines of communications are rivers and canals. Further, it lies astride the major waterways connecting Saigon, South Vietnam's major port, with the sea.

During February and early March, the danger posed by the almost undisputed Communist control of the Rung Sat Special Zone was underscored by three attacks made on merchant shipping enroute to Saigon. The last of these came on 2 March when the Panamanian transport PALOMA was attacked and set afire in a position only four miles up river from the site where an ambush had been launched three days earlier against another merchant ship.

In the aftermath of this attack, COMUSMACV asked that the Seventh Fleet's Special Landing Force be committed for about 10 days to penetrate the Rung Sat Specia1 Zone and disrupt Viet Cong activities. Planning for the operation began on 10 March 8t the headquarters of the Naval Advisory Group, MACV. D-Day was set for 26 March, with the initial landings to come on the Long Thanh peninsula thirty miles southeast of Saigon. The naval force assigned to the operation was the Seventh Fleet's Ready Amphibious Force (COMPHIBRON ONE) consisting of flagship PRINCETON (LPH 5) with ALAMO (LSD 33) and PICKAWAY (APA 222). Attached for special operations were WEISS (APD 135) with a UDT detachment embarked, MERRICK (AKA 97), ROBINSON (DDG 12) for naval gunfire support, HENRY COUNTY (LST 824), WASHOE COUNTY (LST 1165), and RECLAIMER (ARS 42). Aircraft from HANCOCK provided daily air support for the operation.

During the next twelve days, multiple helicopter and surface landings were made by United States and South Vietnamese forces throughout the 300 square miles area in the Rung Sat Special Zone. River and coastal patrol forces supported these operations throughout the period. By the end of the operation, 63 VC were reported killed against U.S. casualties of 5 KIA, 2 missing, and 24 WIA. JACKSTAY resulted in the destruction of three major base complexes upon which the estimated 1000 Viet Cong in the area had depended. Sixty-six individual weapons were taken as well as large quantities of rice and fresh water. The latter commodities were of special importance since the Rung Sat Special Zone has no fresh water and only limited quantities of food naturally available.

The operation was significant in that it entailed the first joint United States-Vietnam amphibious operation of the war. This occurred on 31 March when the Vietnamese River Assault Groups provided a protective screen and minesweeping escort for United States Marines embarked in landing craft. The twenty-four boat convoy worked its way seven miles down the narrow Vam Sat River to make the deepest penetration of the Rung Sat Special Zone. The operation was highly successful, resulting in the destruction of large Viet Cong training, hospital, and supply complexes. This excellent penetration can be attributed to the concept of coupling Vietnamese naval experience in riverine operations with an integral body of assault troops trained in amphibious warfare.

While the areas where the Marines landed were only temporarily sanitized--not conquered--the fact that the Navy-Marine team demonstrated its ability to move freely in the area will weaken the Viet Cong hold in this area and diminish the threat they have posed to the all-important waterway lifelines to Saigon. Of added significance, forces and equipment for this operation were already available in the area, proving again the effectiveness, applicability, adaptability, and flexibility of the Seventh Fleet's amphibious and Marine units.