Mark 14 Torpedo - Early Suspicions

Early Suspicions

On 24 December 1941, Commander Tyrell D. Jacobs in Sargo fired a total of eight torpedoes at two different ships, with no results, and had become very frustrated; when two additional merchantmen came in view, he took extra pains to get it right, pursuing for fifty-seven minutes and making certain TDC bearings matched perfectly before firing two torpedoes at each ship, at an average of 1,000 yd (910 m), very close range. All missed.

A few days after he discovered the torpedoes were running too deep, and corrected the problem, Jacobs detected a big, slow tanker. Again, his approach was meticulous, firing one torpedo at a close 1,200 yd (1,100 m). It missed. Exasperated, Jacobs broke radio silence, openly questioning the Mark 14's reliability.

A similar experience was had by Pete Ferrall in Seadragon, who fired eight fish for only one hit, and began to suspect the Mark 14 was faulty.

Uniquely, Lieutenant Commander John A. Scott in Tunny on 9 April 1943 found himself in an ideal position to attack aircraft carriers Hiyo, Junyo, and Taiyo. From only 880 yd (800 m), he fired all ten tubes, hearing all four stern shots and three of the bow's six explode. No enemy carrier was seen to diminish its speed, though Taiyo was slightly damaged in the attack. Much later, intelligence reported each of the seven explosions had been premature; the torpedoes had run true but the magnetic feature had fired them too early.

Dan Daspit (in Tinosa) carefully documented his efforts to sink 19,000-ton whale factory ship Tonan Maru III on 24 July 1943. He fired four torpedoes from 4,000 yd (3,700 m); two hit, stopping the target dead in the water. Daspit immediately fired another two; these hit as well. With no enemy anti-submarine combatants in sight, Daspit then took time to carefully maneuver into a textbook firing position, 875 yd (800 m) square off the target's beam, where he fired nine more Mark 14s and observed all with his periscope (despite the Japanese firing at it). All were duds. Daspit, suspicious by now he was working with a faulty production run of Mark 14s, saved his last remaining torpedo to be analyzed by experts back at base. Nothing out of the ordinary was found.

At Pearl Harbor, despite nearly all his skippers' suspicions about the torpedoes, Admiral Thomas Withers refused to deactivate the torpedo's Mark VI exploder, arguing torpedo shortages stemming from inadequate production at NTS made it impossible. As a result, his men did it on their own, doctoring their patrol reports and overstating the size of ships to justify using more torpedoes. Only in May 1943, after the most famous skipper in the Sub Force, Dudley W. "Mush" Morton, turned in a dry patrol, did Admiral Charles A. Lockwood, Commander Submarine Force Pacific, accept the Mark VI should be deactivated, but waited to see if Bureau of Ordnance commander Admiral William "Spike" Blandy might find a fix for the problem. The Bureau of Ordnance sent an expert to Surabaja to investigate, who set the gyro backwards on one of Sargo's trial torpedoes; the potentially deadly setting, guaranteed to cause erratic running, was corrected by torpedo officer Doug Rhymes. Though he found nothing wrong with maintenance or procedures, the expert submitted a report laying all the blame on the crew.