US Marine Corps - The Black Vault

332 Amphibians Came To Conquer
larger island of Florida to the immediate north, and to the small hillish
islands of Gavutu and Tanambogo some 3,OOO yards to the eastward of
Tulagi. The Japanese had established their seaplane base at Gavutu Island,
which was reef ringed.
All this dispersion complicated mightily the Scheme of Maneuver, and
the gunfire support plan for the attacking forces in the Tulagi area.
Aerial photographs had shown the Japanese defenses were strongest on
the northeast and southeast beaches of Tulagi. So the southwest beach area
was chosen for the initial main landing. This gave the landing craft for
the main Blue Beach landing a rudimentary straight approach from the
transport area and a real break.
To take Gavutu Island, and to land at Halavo Peninsula, Florida Island,
to the eastward of Gavutu, a dificult turning operation was required
of the landing craft, in addition to picking a circuitous path through a
heavily reefed area.
SCHEME OF MANEUVER
During the planning phases, of the approximately 19,500 embarked
Marines, some 11,000 were assigned to the Guadalcanal assault, 4,000 to
take Florida, Tulagi and Gavutu Islands, and the rest composed the
Division Reserve, whose secondary mission was to act as the Ndeni Landing
Force in Phase 3 of Task One of the PESTILENCE Operation, the second
phase of which was WATCHTOWER.
The agreed upon Scheme of Maneuver for Guadalcanal which governed
the amphibians’ approach to that enemy-held island was a comparatively
simple one for the untested seagoing amphibians to execute their part. The
Scheme of Maneuver for Tulagi, Gavutu, Makambo, and F40rida was
considerably more complicated from the naval viewpoint, although markedly
fewer large transports and cargo ships were involved.
The assault beach on Guadalcanal was 1,600 yards of the 2,000-yard
wide Red Beach. It lay just to the east of the mouth of the Tenaru River
and five miles east of Lunga Point, a good landmark on the north central
coastline. The Japanese air strip was inland a mile, and about half way
between Tenaru and Lunga.
Nine transports and six cargo ships, Transport Group XRAY, under
the command of the second senior naval officer regularly detailed in the