CIA/Brigade 2506 Invasion Fleet Converges on "Rendezvous Point Zulu" South of Cuba

Following the air strikes on airfields on April 15, 1961, the FAR managed to prepare for armed action at least four T-33s, four Sea Furies and five or six B-26s.

All three types could be armed with machine guns and rockets for air-to-air combat and for strafing of ships and ground forces. CIA planners had reportedly failed to discover that the US-supplied T-33 jets had long been armed with M-3 machine guns. The Sea Furies and B-26s could also carry bombs, for attacks against ships and tanks.

No additional air strikes against Cuban airfields and aircraft were specifically planned before 17 April, but pilots' exaggerated claims gave the CIA false confidence in the success of the 15 April attacks, until U-2 reconnaissance photos on 16 April showed otherwise. Late on 16 April, President Kennedy ordered cancellation of further airfield strikes planned for dawn on 17 April, to attempt plausible deniability of US direct involvement.

On April 16, Merardo Leon, Jose Leon, and 14 others staged armed rising at Las Delicias Estate in Las Villas, only four survived[30] Leonel Martinez and 12 others took to the countryside (ibid). On April 17, 1961, Osvaldo Ramírez (then chief of the rural resistance to Castro) was captured in Aromas de Velázquez and immediately executed.[36] The CIA was unaware or unconcerned at this repression's effects on the planned operation (notably two former "Comandantes" Humberto Sorí Marin and William Alexander Morgan). Others executed included Alberto Tapia Ruano, a Catholic youth leader. Some estimates quote several hundred thousand people as being imprisoned before, during, and after the invasion.

Late on April 16, 1961, the CIA/Brigade 2506 invasion fleet converged on "Rendezvous Point Zulu", about 65 km (40 miles) south of Cuba, having sailed from Puerto Cabezas, Nicaragua where they had been loaded with troops and other materiel, after loading arms and supplies at New Orleans. The fleet, cryptically labelled the "Cuban Expeditionary Force" (CEF), included five 2,400-ton (empty weight) freighter ships chartered by the CIA from the Garcia Line and outfitted with anti-aircraft guns. Four of the freighters, Houston (code name Aguja), Río Escondido (code name Balena), Caribe (code name Sardina), and Atlántico (code-name Tiburon), were planned to transport about 1,400 troops in seven battalions of troops and armaments near to the invasion beaches. The fifth freighter, Lake Charles, was loaded with follow-up supplies and some Operation 40 infiltration personnel. The freighters sailed under Liberian ensigns. Accompanying them were two LCIs (Landing Craft Infantry) "purchased" from Zapata Corporation then outfitted with heavy armament at Key West, then exercises and training at Vieques Island. The LCIs were Blagar (code-name Marsopa) and Barbara J (code-name Barracuda), sailing under Nicaraguan ensigns. The CEF ships were individually escorted (outside visual range) to Point Zulu by US Navy destroyers USS Bache, USS Beale, USS Conway, USS Cony, USS Eaton, USS Murray, USS Waller. A task force had already assembled off the Cayman Islands, including aircraft carrier USS Essex with task force commander John A. Clark (Admiral) onboard, helicopter assault carrier USS Boxer, destroyers USS Hank, USS John W. Weeks, USS Purdy, USS Wren, and submarines USS Cobbler and USS Threadfin. Command and control ship USS Northampton and carrier USS Shangri-La were also reportedly active in the Caribbean at the time. USS San Marcos was a Landing Ship Dock that carried three LCUs (Landing Craft Utility) and four LCVPs (Landing Craft, Vehicles, Personnel). At Point Zulu, the seven CEF ships sailed north without the USN escorts, except for San Marcos that continued until the seven landing craft were unloaded when just outside the 5 km (3mi) Cuban territorial limit.

The ships of the convoy were assembled at point Zulu and proceeded from there to point Charlie- Charlie where two destroyers escorted them to the landing point.

The two United States destroyers were code-named Santiago and Tampico. Aerial cover was provided by a two-engine observation aircraft.

Enroute to point Charlie-Charlie, the crews and troops were briefed on the operation and specifically told that the landing was in no way connected with an uprising from within as the invasion was strictly an operation by the Brigade.

The Brigade consisted of five battalions with a total strength of 1,258 infantrymen and approximately 300 men for the supply services. The battalions had the actual strength of a United States infantry company and almost no heavy weapons.

There was no artillery and the only support was given by six Mark IV Sherman tanks which joined the invasion in three L.C.T.'s and were landed before the infantrymen. Apparently the lack of sea transports forced the planners of the operation to reload the L.C.T's with the motorized equipment, land it , and then return to the troop transports to pick up the infantrymen. Each L.C.T. carried two tanks, two trucks, and two jeeps. The infantrymen were armed with Garand rifles and M1 carbines plus heavy weapons consisting of six 60 mm mortars, six 81 mm mortars, an six 4.2 mortars. A number of 57 mm recoilless rifles and .50 caliber machine guns was also used by the expeditionary forces.