Marine G-4 planners suggested one of the most daring of all the calculated risks. This was the decision to use LCVPs for the RED Beach landings because their comparative speed would clear the landing area for the beaching of eight LSTs—all that could be crammed into the narrow confines of this strip of urban waterfront. Each was to be loaded with ammunition, rations, water, and fuel. Obviously these Navy workhorses, nicknamed “large slow targets”, would be easy marks for NKPA shore guns, but this was a chance that had to be taken if the assault troops were to be adequately supplied.
There was not time, of course, to unload and retract the ships during the period of evening high tide. They must be unloaded during the night and taken out on the morning tide.
Since it was not considered feasible to land LSTs on BLUE Beach, that area would not be developed beyond the needs of the immediate assault. For this purpose, 16 preloaded LVTs were to be used as floating dumps until the 1st Marines could link up with the other regiment.
These were the essentials of the Landing Force plan. H-hour was ultimately determined from a study of late photographs which brought about a slight change in estimates. Since a tide of 25 feet (two feet higher than the initial estimate) appeared to be necessary for the LCVPs and LVTs to reach the sea wall, H-hour was set at 1730 instead of 1700. The completed Landing Force plan provided for these steps:
(1) BLT-3 of RCT-5 to land on Beach GREEN at L-hour on D-day and seize Wolmi-do.
(2) RCT-5 (— BLT-3) to land on Beach RED at H-hour, seize Objective O-A, effect a juncture with RCT-1, and prepare for further operations to the east in coordination with RCT-1 to seize the FBHL.
(3) RCT-1, to land on Beach BLUE, with two battalions in assault, seize Objective O-1, and prepare for further operations to the east in coordination with RCT-5 to seize the FBHL.
(4) 11th Marines (— 3d Bn) (96th F. A. Bn, USA, attached) to land 1st and 2d Bns on Beach GREEN at H-hour, occupy positions on Wolmi-do and support seizure of the beachhead with priority of fires to RCT-1. Remainder of artillery to land on call.
(5) ROK Marines, initially in Division reserve, to land over Beach RED on call and conduct operations to occupy the city of Inchon in coordination with RCT-5.
(6) 1st Tank Bn (—) (Reinf.) to be prepared to land on order one company in LSU on Beach GREEN, remainder of battalion on order on beaches to be designated.