The navy carrier torpedo bomber Tenzan or Nakajima B6N, was codenamed "Jill" by the Allies. It was the replacement of the famous Nakajima B5N ("Kate") torpedo bomber, and although more B6N's were built than B5N's, the plane never achieved the spectacular success of its predecessor. It entered service in the second half of 1943 but wouldn't be used on a large scale until June 1944 during the air and sea battles in the Philippine Sea for the Mariana Islands. Later it would be used in Taiwan, the Philippines, Iwo Jima, Okinawa, and for Kamikaze attacks. The crushing air superiority of the Allies and the loss of nearly all the Japanese aircraft carriers and their trained pilots led to many Tenzans being lost, while never having had a chance to prove their worth. In spite of the fact that the Tenzan never achieved any real successes, it was undoubtedly one of the best carrier based torpedo bombers of WWII.