The TMC Mine. This mine was an enlarged TMB which was designed to meet the re-quest of German field commands for a torpedo mine with a greater target area then the TMB. It existed in two models, TMC I and TMC II. The only differences between the two models was the size of the unit compartment, the weight of the charge and the total weight of the mine. The external appearance of the case is the same.

Description

TMC I

TMC II
(Larger unit compartment)

Total weight lb.

2,450

2,200

Charge - lb.

2,050

1,760

Neg. buoyancy lb.

860

700 (600 when DM I used)

Length

134 in.

134 in.

Units fitted

M 1, A 2, A 2st, AT 3

DM I, MA 2/3

Figure 105 – TMC I Mine

Operation. When the mine is launched, a spring-loaded safety bar is released from the top center line of the case, thereby unlocking the hydrostatic clock and booster-release mechanism. Water pressure depresses the clock spindle and operates the booster-re-lease mechanism, respectively, at a depth of 15 feet, starting the clock and allowing the booster to house over the detonator. The clock runs off its delay setting and the firing unit begins the arming cycle.

The only self-disarming device is the 80-day-clock, which may be fitted to sterilize the mine at the end of its set period by shorting out the battery.