31 August, 1945

     

    SUBJECT: Report on Operations and Material - Fort Drum - During the Bataan - Corregidor Campaign, 8 December 1941 - 6 May 1942.

     

    TO: Commanding General
      Army Ground Forces
      Washington, DC

     

     

    1. Orientation.
         
      a. Geographical.  The entrance to Manila Bay is guarded by 4 islands.
        (1)   Corregidor - (Fort Mills)
        (2)   Caballo - (Fort Hughes)
        (3)   El Fraile - (Fort Drum)
       

    (4)   Carabao - (Fort Frank)

         
      b. Tactical Command.  The tactical command at the beginning of World War II was known as the Harbor Defenses of Manila and Subic Bays.  This report deals with Manila Bay only.  The defenses were divided into two parts, the AA Command and the Seaward Defenses Command.  Under the Seaward Defense Command were groups I, II, III and IV.  (There were no groupments).  The mission of the Seaward Defense Command was "to deny the enemy the use of Manila Bay and to protect the detachment of our Navy there from".
         
    2. Fort Drum - Description and Organization.
         
      a.  Fort Drum was constructed on the small island of El Fraile in the channel of Manila Bay in 1913, and was termed the "Concrete Battleship".  The entire top of the original island was cut away to below the surface of the water.  On this foundation, the reinforced concrete fort was constructed.  When completed, it was 350 feet long by 144 feet wide and the main top deck extended 40 feet above mean low water.  The general outline of the hull, as seen from above, resembled a ship with the pointed bow toward the China Sea.  The exterior walls of the fort were approximately 20 feet thick, of reinforced concrete.  The deck had an overhead thickness of 18 feet of reinforced concrete and steel.  Thin places on the top deck over the casemates and where the observation wells existed, were compensated for by an additional 3 or 4 inches of steel plate.  The overall result was a top deck of uniform strength generally equivalent to 18 feet of reinforced concrete.  The interior of the fort was cut into several compartments, constructed on various internal levels.  The lower level was the engine room, the floor of which was 6 feet below mean low water.  Above this was the main internal deck called the "Typhoon Deck".  It was here that most of the troops were quartered.  Other compartments housed the fuel tanks, the powder and projectile rooms, plotting room, storage facilities, kitchen and mess hall compartments.  Access to the fort was had by means of the sallyport toward the stern which ran entirely across the ship, generally from north to south.  The cover for the sallyport and entrance to the typhoon deck was another approximately 20 feet of concrete which had been an afterthought and had been added to Fort Drum as protection to the interior of the ship at a later date.