The Assault on Fort Drum


By Lieutenant Perry Reed McMahon*


It was like a mid-ocean piratical raid on a rich and helpless merchant vessel; or maybe it was like a medieval battle with knights­in-armor thundering across the drawbridge into the castle grounds–it was like anything except what it actually was – an unusual instance of a highly developed phase of modern warfare – the commando raid on Fort Drum, "concrete battleship" in Manila Bay.

It was thus that Staff Sgt. Thomas J. Hooper, of the 38th "Cyclone" Division described the retaking of Fort Drum, on El Fraile Island. He was one of the troops who made the assault.

The operation which neutralized Fort Drum as a Jap listening post did not rate more than a few casual words in a passing communique. Behind the official phraseology, however, there is a story of one of the most unusual operations on record and one of the shortest.

It required only a few minutes to finally reduce the Manila Bay outpost–and here again it must be pointed out, the big-14-inch rifles which stood on the deck had been destroyed before the Americans pulled out in 1942. The Japs could not replace them. It was standing, more or less as a helpless hulk.

Yet, here is another example of the work of our Engineers. Heavy caliber bombs bounced off Drum's heavy concrete decks with little damage. The heavy rifles of cruisers fired point blank, pierced the heavy armor-plate of the portal guns, but Japs huddled in safety behind them, and came out to shoot when the infantry boarded the "ship."

What kind of a battle would have ensued if Old Drum had her original weapons is, of course, a matter of conjecture, but it certainly would have been a different story.

When Fort Drum was completed, it was 350 feet long and 135 feet wide – and something to be proud of. The concrete walls were 36 feet in width and the top deck 40 feet – strong enough to withstand land, naval, or air bombardment.

It mounted two twin 14-inch gun turrets on the top deck and two six-inch rifles built into the north (starboard) and south (port) sides of the island. There were four levels inside. At the east end or "stern" there were two sally ports on both port and starboard. Itwas here that boats carrying men, mail, and provisions to the Fort tied up. The ports opened onto an axial tunnel running through the island and connecting with all four levels.

Assigned to the task of cleaning out Fort Drum, the 2d battalion, 151st Infantry, of the 38th Division, had already paved the way by mopping up on Corregidor, and invading and securing near-by Caballo.

Caballo was the inspiration for the plan by which Fort Drum was reduced. On this horse-shaped rock the entire Jap garrison had been killed within a few days, except a band of sixty or so who had holed up in two huge mortar pits, which resisted all efforts of infantry engineers, and artillery to reduce them. Of reinforced concrete, eight to ten feet thick, the walls at Caballo had originally been built by the Americans and later improved by the Japs.

Various plans were offered and rejected.

A plan formulated by Lt. Col. Fred C. Dyer, G-4 of the 38th which had worked so well on Caballo, was finally accepted. An LCM was fitted with a centrifugal pump and two tanks capable of holding more than 5,000 gallons. A special mixture of two parts diesel oil and one part gasoline was prepared and pumped into the tanks.

Brigadier General (then Colonel) Robert H. Soule, assistant division commander, selected this plan as the one most likely to reduce Drum.

Training and preparations for the landing were begun a week before D-Day. On Corregidor a reinforced platoon of riflemen from Company "F," 151st Infantry and a platoon of demolition men from Company "B," 113th Engineers, made repeated dry runs so that each man should know what he must do when he stepped atop Fort Drum.

On the parade ground at Corregidor the surface of the island was simulated. Dummy gun turrets and air vents were built. Each rifleman was assigned a specific opening in the surface of the fort to cover. Every gun turret, every air vent, every crack in the surface was to be covered with an M-1 or a BAR, so that no enemy would be able to come topside. The infantrymen practiced repeatedly so that each one was able to carry out his appointed task without a hitch.

The engineers were trained in planting explosives at strategic intervals on the rock, while others went through the motions of dragging a fire hose topside from the LCM which was scheduled to pull up alongside in the manner of the Caballo operation.

Under the direction of Major Robert E. Hisle, S-3 of the 113th Engineers, an especially designed wooden ramp was built from the conning tower of the LSM, much like a drawbridge. It was located on the starboard side and let down at right angles to the length of the ship. The ramp was necessary since the height of the island—40 feet—prevented the troops from landing in the usual manner.

Plans for effecting an entry through the sally ports were rejected because a Naval reconnaissance force landing from a PT boat at these points had received machine-gun fire from the tunnel.

April 13 — a Friday — was selected by an unsuperstitious staff as D-Day; H-Hour was set at 1000. At 0830 the troops loaded from Corregidor's south dock walking over the narrow plank from the pier to the landing boat.

The engineers were burdened with 600 pounds of explosives, while the infantry carried rifles and bandoleers of ammunition. In the crow's nest towering above the landing ramp a BAR man was stationed, while below him on a precarious platform a light machine gun was set up, thus providing adequate protection for the troops who were to land.

Precisely at 1000 the LSM pulled up at Fort Drum. It was a ticklish operation to maneuver the squat bulky craft so that it snuggled tightly against the island and held there steadily.

As the LSM moved up on the port side, three LCVP's manned by naval personnel came up alongside the larger ship, bows first, and with motors racing pushed against the LSM, shoving it against the rock.

As soon as the LSM was close enough, sailors standing in the well-deck let down the ramp by means of a block and fall. Immediately, other sailors rushed ashore across the ramp carrying lines which were fastened to the gun turrets or any other available projection to make the LSM more secure.

The infantrymen in single file moved up the circular ladder to the conning tower. Sailors helped them climb to the ramp and onto the rock, like so many charging knights.

Despite the strong lines and the LCVP's, the LSM pitched and rolled and the ramp scraped dangerously back and forth over the concrete top deck.

The LCM used in the Caballo invasion was brought in behind the larger vessel and a fire hose was passed up to the engineers on the LSM by means of a line. The line was thrown up to the deck of Fort Drum where other engineers grabbed it and brought up the hose.

The Infantry did its job well. Every vent was covered by a rifleman. A Jap could never have gotten his head above the surface without having it blown off. The engineers set about their task of planting the explosives with sureness and dexterity. Particular attention was given the powder magazine which was below the surface on the first level, and protected by an armor plate six inches thick under the layer of reinforced concrete.

In ten minutes the job was finished; thirty-minute fuses were lighted; and the men began to file back onto the ship.

Once at one point, the hose broke and while the break was being repaired, the first opposition developed. A Jap sniper hidden in one of the six-inch gun turrets on the port side opened up. His aim was bad on the first couple of shots. Although the sniper couldn't be seen, sailors manning the LSM's 20mm guns were anxious to spray the turret, but a redheaded ensign yelled from the bridge that oil was leaking through an aperture in the turret and that shells would undoubtedly ignite it, jeopardizing the success of the whole operation. Fuming, the sailors held their fire but remained at their positions exposed to the enemy rifleman.

The sniper opened up again with another volley and a bullet passed through the fatigue jacket of Sgt. Mack Thomson, the colonel's driver and radio operator. Thomson, unaware that the sniper had been firing, was standing some distance away toward amidship. The bullet made seven holes passing through the jacket, baggy pocket, and sleeve. Thomson was not even scratched.

Another bullet grazed Cpl. Vincent Glennon's left hand. At the first shot this aid man dropped behind a ventilator for protection. But a bullet passed through the light, thin metal of the ventilator, creasing his hand and drawing no more blood than a pin scratch.

A sailor was less fortunate. One shot split the fittings that connected the three air hoses to the gyroscopic sight of a 20mm gun and several of the pieces embedded themselves in his throat. He had been manning the gun at the time. Army and Navy medical corpsmen teamed up to give him an immediate blood transfusion and dress his wounds. Those were the only casualties–a cheap price for Fort Drum.

After Colonel Lobit and his men returned safely, the lines were cut, the LCVP's backed off and the LSM pulled away, stopping about a thousand yards off to watch the show. In thirty minutes there was a slight explosion. Nothing else happened. Disappointment was written in the faces of the men. They'd have to do it all over again now. But no.

Suddenly it seemed as though the whole island were blown out of the sea. First there was a huge cloud of smoke rising from the island, then seconds later, the GI's on the LSM heard the thunderous explosion. Blast after blast ripped the concrete battleship; debris was showered into the water, creating hundreds of small geysers; a huge flat object, later identified as the six-inch, 12 foot square slab of armorplate protecting the powder magazine, was blown hundreds of feet into the air to fall back into the sea with a large splash.

A satisfied cheer went up as the explosions rocked the air and there were the usual salty comments in unvarnished language.

As the LSM moved toward Corregidor more explosions were heard and dense black smoke continued to rise from the "impregnable" battleship.

Two days later–on a Sunday – the drama was partially reenacted. This time the object was to gain admittance to the lower levels. But wisps of smoke that curled up from the ventilators indicated the (illegible)  was still burning. Major Paul R. LeMasters, commander of the 2d Battalion, called the descent off and the disappointed troops returned to Corregidor.

The following day the troops again returned. Now they were able to make their way as far down as the second level but again smoke forced them to withdraw. Eight Japs — dead of suffocation—were found on the first two levels. Two days later another landing party returned and this time was able to explore the whole island. The bodies of sixty Japs — burned beyond recognition — were found on the third level in the boiler room.

The inside, of course, was a shambles. The walls were blackened with smoke and what installations there were had been blown to pieces or burned.

Someone had suggested that possibly Fort Drum was being used or been used to detain American prisoners of war. No evidence was found to support this theory. The souvenir hunting wasn't very good.



This article was originally published in the Coast Artillery Journal, July-August 1945 Edition as "DEFENSES OF MANILA AND SUBIC BAYS - THE FALL OF CORREGIDOR" and is republished as the third part of a five-part series at Corregidor Then and Now. For more reading visit:





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