Carbonit Mine
The German Carbonit Mines were made by the Carbonit Company of Hamburg. This article is based, initially, on a British report on German mines from July, 1917.[1]
| Carbonit Mine | |
| Weight | 836 lbs. |
| Casing | 0.2 in. welded steel |
| Detonator | 2 Tetryl detonators in parallel |
| Primer | 2.2 lbs. of lightly compressed T.N.T. |
| Charge | 220 lbs. of cast T.N.T. |
| Buoyancy | 240 lbs. |
| Height on rails |
over 6 feet high |
| Diameter | – |
| Sinker weight | 660 lbs. (330 more can be added) |
| Mooring wire | 330 feet of 1.25-in wire, breaking strain 4.5 tons |
Firing was done by four volt batteries at a current of 0.1 ampere or more.
It would sink to the bottom with its sinker and rise about 15-20 minutes later when a soluble plug dissolved.
The sinker was an iron plate with rollers to engage a mine rail on the hosting vessel.
Trials in H.M.S. Vernon
In a tideway trial, a two knot tide was found to cause the mine to sink just 6 inches with 37 feet of mooring wire out — a better depth-keeping than British mines. This mine had 40 pounds more buoyancy than British weapons. The horns proved very good at triggering on Vindictive, as the mine rolled as the ship passed alongside. The mine passed a six day endurance test easily, and two withstood a counter-mining test of 220 pounds of T.N.T. exploded 45 yards from them in 15 feet of water.
Fish Type
These mines were unusual in that their wire spool was in the sinker, not in the mine body. The mine was placed into a cradle on the sinker just before deploying.[2]
| Carbonit "Fish Type" Mine | |
| Weight | lbs. |
| Casing | 0.2 in. welded steel? |
| Triggers | four horns |
| Detonator | |
| Primer | |
| Charge | 200 kgs. T.N.T. |
| Buoyancy | |
| Height | |
| Diameter | – |
| Sinker weight | |
| Mooring wire | |
Footnotes
Bibliography
- Admiralty (July, 1917). German Navy: Part IV, Section 3. Torpedoes, Mines, Etc. (C.B. 1182) The National Archives. ADM 186/228.
