The Sturmmörserwagen 606/4 mit 38 cm RW 61, better known as the Sturmtiger (German: "Assault Tiger") was a German mechanized rocket launcher designed during the Second World War. It was built on a Tiger I chassis. This vehicle was designed in 1942 but entered production in April of 1944 and then late that year in the service and was intended as an ultra heavy mechanized artillery. The Sturmtiger fired a rocket from his 38 cm RW 61 rocket launcher, designed for the Marine. The design of the rocket launcher caused some problems. The hot rocket exhaust could not be vented into the fighting compartment nor could the barrel withstand the pressure if the gases were not vented. Therefore a ring of ventilation shafts were put around the barrel which channeled the exhaust and gave the weapon somewhat of a pepperbox appearance. This forced after each shot the Sturmtiger moved because his position was known to the enemy. A counterattack by enemy artillery was therefore often do not last long. The rockets had a range of 4-6 km and were meant for fighting in urban areas where the enemy was entrenched in buildings. The huge explosion claimed many buildings to the ground. Due to the bulkiness of the ammunition, only 14 rounds could be carried, of which one was already loaded, with another in the loading tray. The rest were carried in two storage racks. To help with the loading of ammunition into the vehicle, a loading crane was fitted at the rear of the superstructure, next to the loading hatch. Even then, the entire five man crew had to help with the loading. There were only 18 Sturmtigers made. Most have done virtually no service because they frequently broke because they were almost impossible to maintain.