This multiple rocket launcher, used for antiaircraft barrage purposes and known as the “Föhn” is of different design from any other weapon of its type used by the Germans. Launching sites were located along river fronts, indicating the use of this weapon against river crossings. There are 35 individual launchers, each 31 inches long and approximately 7.3 cm square, assembled in 5 horizontal and 7 vertical rows. The rockets are fired by hammer type firing pins mounted on horizontal shafts. All 35 of the pins are actuated by a single trigger. The whole assembly measures 32 inches from top to bottom, and 23 inches from side to side. A simple clamp at the rear of the racks holds the rockets in position until firing takes place. The frame of the assembly is made of 3/16-inch metal.
A trunnion, set in each side of this framework, rests upon arms extending up from the pedestal base. The weapon, with its pedestal base, is used with either a mobile or fixed mount. When used as a mobile mount, the launcher is fitted with a circular metal folding platform mounted on a 2-wheeled trailer. The fixed launchers are not provided with the folding platform, and it is believed that they are normally set up more or less permanently on sheet iron platforms.
The sight, trigger mechanism, and elevating and traversing mechanisms are mounted on the inside of a metal protective shield located on the left side of the launcher. Elevation is from -10° to 90°. The upper part of the front wall of the shield is made of transparent plastic for sighting purposes.
The 7.3 cm Raketen Sprenggranate, used with the launcher, is a spin stabilized rocket fitted with a nose percussion fuze and a self-destroying delay element ignited by the burning propellant.
