The Rocket Launcher T34 (Calliope) was a tank-mounted multiple rocket launcher used by the United States Army during World War II. The launcher was placed atop the Medium Tank M4, and fired a barrage of 4.5 in (114 mm) M8 rockets from 60 launch tubes. It was developed in 1943; small numbers were produced and were used by various US armor units in 1944-45. It adopts its name from the musical instrument "Calliope", also known as the steam organ, which had similarly lined pipes.
Rocket Launcher T34 (Calliope) - Version carrying 60 4.5 in (114 mm) rockets in arrangement of a group of 36 tubes on the top, and a pair jettisonable groups of 12 tubes (24 tubes of jettisonable groups) on the bottom (Not jettisonable from M4A1 Sherman variant).
Rocket Launcher T34E1 (Calliope) - Same as T34 but groups of 12 jettisonable tubes replaced by groups of 14 tubes.
Rocket Launcher T34E2 (Calliope) - Caliber of rockets increased from 4.5 in (114 mm) to 7.2 in (183 mm), number of tubes remains at 60. Saw combat in 1944-1945.