The Vietnam War Part 11 – Operation Double Eagle- The Massive Invasion That Found Nothing. D

South Vietnam, January 1966. This is ground zero. Operation Double Eagle was a major US Marine  Corps and South Vietnamese operation conducted   in southern Vietnam from the 28th of January  to the 17th of February 1966. It was part of a   larger Allied effort along the border coordinated  with the US Army’s Operation Masher, later renamed   Operation White wing in neighboring Binh Dinh  Province.

The objective was to locate and disrupt   suspected VietCong and North Vietnamese Army  formations and their bases in an area of roughly   500 square miles. The operation was commanded by  Brigadier General Jonas M. Platt, who reactivated   Task Force Delta for the mission. The main  marine infantry units were the third battalion,   First Marines, Second Battalion, Fourth Marines,  Second Battalion, Third Marines, and elements of   the Second Battalion, 9th Marines.

Supporting  them were marine artillery, reconnaissance and   engineering units, including the third battalion  11th marines, reconnaissance elements, engineers,   amphibious forces, and substantial helicopter  support from the Marine Aircraft Group 36. The   operation was coordinated alongside the ARVN  Second Division. The initial assault was an   amphibious landing on the 28th of January at  Red Beach.

Third Battalion, First Marines,   and Second Battalion, Fourth Marines, came ashore  from a large Navy amphibious force. The operation   was described by Marine historians as the largest  extended amphibious operation conducted by the   US Navy and Marine Corps since Inchon in 1950.  Naval gunfire and marine aviation supported the   landing while amphibious tractors carried troops,  artillery, and equipment in land.

The plan used   three broad phases: reconnaissance, landing,  and exploitation. Before the main assault,   marine reconnaissance teams and an artillery  battery were positioned near the Ba Tơ Special   Forces camp to monitor enemy movements and provide  fire support. After the beach head was secured,   additional battalions were moved in land by  helicopter.

Second battalion, Third Marines,   part of the Seventh Fleet Special Landing Force,  was lifted from amphibious shipping into an inland   landing zone, while Second Battalion, 9th Marines  subsequently moved into the mountains. Mobility   was central to the operation. Task Force Delta  used helicopters to conduct repeated search and   destroy movements, rapidly shifting companies and  battalions between landing zones.

During Operation   Double Eagle, the force conducted 17 battalion and  19 company or battery helicopter lifts as well as   additional amphibious and overland movements.  Artillery was repeatedly re-positioned so that   advancing infantry could remain within supporting  range. Logistically, the operation depended   heavily on the combination of amphibious shipping,  helicopters, artillery, and forward supply bases.

Marine Aircraft Group 36 established a helicopter  operating and logistics area known as Johnson City   near the beach. It provided fuel, ammunition,  supplies, maintenance, and medical support,   allowing helicopters to sustain rapidly moving  ground forces. Helicopters also provided troop   transport, emergency resupply, reconnaissance,  close air support, and medical evacuation.

The Marines expected to encounter substantial  enemy forces, including the 18th and 95th NVA   regiments and the VietCong Second Main  Force Regiment. Intelligence estimates   suggested thousands of communist troops were  operating in or around the area. In practice,   however, much of the expected enemy force had  already moved south towards Bình Định Province.

The Marines consequently encountered mainly small  groups using hit-and-run tactics rather than the   large formations they had hoped to engage. This  created the operation’s central problem. American   forces had overwhelming mobility and firepower,  but the enemy could avoid decisive engagements,   disperse into small groups, and exploit difficult  terrain.

Marine reconnaissance nevertheless   located enemy personnel and supplies on several  occasions, allowing artillery and aircraft to be   brought in against them. The operation also  disrupted local communist infrastructure and   captured significant quantities of food and  military supplies. By the 17th of February,   Operation Double Legal had produced a US Marine  reported total of 312 enemy killed and 19   captured.

The Marines also reported capturing  approximately 20 tons of rice, 6 tons of salt,   other supplies, 18 weapons, and 868 rounds of  ammunition. Marine losses were 24 killed and   156 wounded. These figures should be understood as  wartime operational reports, particularly because   enemy casualty estimates based on battlefield  body counts were inherently difficult to verify.   The operation did not achieve its principal  objective of forcing the major enemy formations   into a decisive battle. The suspected large units  had avoided the Marine advance.

Nevertheless,   the operation demonstrated that the Marine  Corps’s ability to combine amphibious assault,   helicopter mobility, artillery, naval gunfire,  tactical aviation, and reconnaissance over a   very large area. In summary, Operation  Double Eagle was tactically impressive,   but strategically inconclusive.

The Marines  successfully landed a large force, moved it   rapidly across difficult terrain, and inflicted  casualties while capturing supplies. However, the   enemy largely avoided destruction by withdrawing  or dispersing before the main force arrived. The   operation therefore illustrated a fundamental  difficulty of the Vietnam War. Superior American   mobility and firepower could clear an area,  but without a permanent South Vietnamese   presence capable of holding it, communist forces  could return after the Marines moved elsewhere.