Japanese steam warship Kaiten No. 2

Takao Maru (高雄丸) or Kaiten No.2 (第二回天) was a steam warship of the former navy of the Bakufu during the Boshin War of 1868-1869. She had been seized from the navy of the fief of Akita.

She was originally built in New York as USRC Ashuelot, a Pawtuxet-class cutter screw steam revenue cutter built for the United States Revenue Marine during the American Civil War. She was purchased by Akita Domain (秋田藩) and named Takao Maru, then transferred to the Republic of Ezo (蝦夷共和国), a short-lived state established by former Tokugawa retainers (Bakufu), and renamed Kaiten No.2. She was armed with four smoothbore cannon on the side, and a powerful Armstrong cannon with explosive shells, installed on a rotating base.

She participated in the Battle of Miyako Bay, when three Bakufu warships were dispatched for a surprise attack against Imperial forces. For the battle, Eugene Collache, a French navy officer, was put in command of the Kaiten No.2, on which were sailing 40 seamen and 30 samurai. The two other ships were the Kaiten No.1 (Kaiten Maru) and the JAPANESE WARSHIP Banryū.

The ships encountered bad weather, in which the Kaiten No.2 suffered engine trouble, and the Banryu was separated. The Banryu eventually returned to Hokkaido, without joining the battle. To create surprise, the Kaiten No.1 planned to enter Miyako harbour with an American flag. Unable to achieve more than 3 knots due to engine trouble, the Kaiten No.2 trailed behind, and the Kaiten No.1 first joined battle. The Kaiten No.1 approached the enemy ships and raised the Bakufu flag seconds before boarding the French-built Kōtetsu, of the opposing Imperial navy (the first Japanese ironclad). The Kōtetsu managed to repel the attack with a Gatling gun, with huge loss on the attacking side. The Kaiten No.1, pursued by the Imperial fleet, steamed out of Miyako Bay just as the Kaiten No.2 was entering it. The Kaiten No.1 eventually escaped to Hokkaido, but the Kaiten No.2 was unable to leave the pursuers and wrecked herself voluntarily. The Kaiten No.2 was set on fire by the escaping rebels and exploded.

Collache was imprisoned by the Japanese, judged and condemned to death, but he was finally pardoned. At the end of the conflict, he was sent to Tokyo where he rejoined Jules Brunet, and later left for France.