GERMAN UNDERWATERS ORDNANCE MINES |
Chapter 10 - SWEEP OBSTRUCTORS |
STATIC CONICAL SWEEP OBSTRUCTOR |
Reisboje. This is a moored, conical float, laid by surface craft, fitted with mechani-cal cutters on its mooring cable. It is a non-explosive, anti-sweep device, laid in and around moored-mine fields. |
Decription of Case |
Shape |
Conical; resemble explosive conical floats, Type C and D |
Material |
Steel |
Diameter (base) |
19 in. |
Length |
44 in. |
Charge |
1 lb. 13 oz. |
Total weight in air |
50 lb. (approx.) |
The float is moored to a concrete block, 33 in. by 28 in. by 27 in., which is surrounted by a steel drum, 33 in. high and 25 in. in diameter. The mooring cable (300 ft. max.) is fitted with four mechanical cutters. The uppermost cutter is attached two feet below the float, and the others at 4 ft. 3 in. intervals. Seven cone-shaped, steel beads are woven into the mooring cable between the float and the uppermost cutter. |
Operaton. A stop pin is inserted in the anchor prior to laying to adjust the depth set-ting. The float therefore takes depth by fixed mooring-cable setting. Dissolution of a soluble plug releases the float from its anchor. The float then rises, pulling the cutters from brackets inside the drum and unreeling the cable. |