The Take Ichi convoy sailed from Shanghai bound for Manila on 17 April, and initially comprised 15 transports and the 6th Escort Convoy Command.
Seven of the transports were traveling to Manila only and the 32nd and 35th Divisions were each carried by four vessels.
Allied code breakers decrypted radio signals relating to the convoy's departure and subsequent intercepts allowed radio traffic analysts to follow its progress south.

Intelligence from the intercepted radio signals was used to guide the submarine USS Jack toward the convoy, and she made contact with it off the northwest coast of Luzon on the morning of 26 April.
The submarine's captain—Commander (later Rear Admiral) Tommy Dykers—attempted to maneuver into a position to attack the convoy but lost contact when he was forced to evade a Japanese submarine.
An aircraft sighted and attacked Jack a few minutes later, but the convoy did not change course.
Dykers regained contact at midday after sighting Shirataka's heavy smoke exhaust and surfaced an hour before sunset to get into an attack position.
He was forced to submerge, however, when another aircraft attacked the submarine.

Jack surfaced again after dark, and successfully attacked after the moon set.
Dykers found that the Japanese escorts were alert, and was unable to penetrate the convoy.
As a result, he attacked three times by firing a total of 19 torpedoes from long range into the mass of ships at the center of the convoy.
These attacks sank the 5,425-ton freighter SS Yoshida Maru No.
1, which was carrying an entire regiment of the 32nd Division.
All 3,000 soldiers onboard drowned when the ship sank quickly.
The remaining Japanese ships continued to Manila, arriving there on 29 April.
The Take Ichi convoy sailed from Shanghai bound for Manila on 17 April, and initially comprised 15 transports and the 6th Escort Convoy Command. Seven of the transports were traveling to Manila only and the 32nd and 35th Divisions were each carried by four vessels. Allied code breakers decrypted radio signals relating to the convoy's departure and subsequent intercepts allowed radio traffic analysts to follow its progress south.
Intelligence from the intercepted radio signals was used to guide the submarine USS Jack toward the convoy, and she made contact with it off the northwest coast of Luzon on the morning of 26 April. The submarine's captain—Commander (later Rear Admiral) Tommy Dykers—attempted to maneuver into a position to attack the convoy but lost contact when he was forced to evade a Japanese submarine. An aircraft sighted and attacked Jack a few minutes later, but the convoy did not change course. Dykers regained contact at midday after sighting Shirataka's heavy smoke exhaust and surfaced an hour before sunset to get into an attack position. He was forced to submerge, however, when another aircraft attacked the submarine.
Jack surfaced again after dark, and successfully attacked after the moon set. Dykers found that the Japanese escorts were alert, and was unable to penetrate the convoy. As a result, he attacked three times by firing a total of 19 torpedoes from long range into the mass of ships at the center of the convoy. These attacks sank the 5,425-ton freighter SS Yoshida Maru No. 1, which was carrying an entire regiment of the 32nd Division. All 3,000 soldiers onboard drowned when the ship sank quickly. The remaining Japanese ships continued to Manila, arriving there on 29 April.
Take Ichi convoy