ROBERT M. Wrote:
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>

> There had to be a reel or drum in the torpedo and
> on the inside or
> outside of the torpedo tube's breech door, for the
> guidance wire. If this was the case, how did the
> guidance wire pass through the large "piston" at
> the rear of the tube? The answer may be found in
> the following paragraph......
>
> On page 264, under the title "T10 Spinne" the
> following statement is made: "A standard
> electric torpedo (was) modified for wire guidance
> and developed from 1942 for coast defence. Total
> weight was 1620kg (3571#) and range 5000m (5470
> yds) at 30 knots. Steel wire 0.010in diameter,
> with insulation which reduced the specific gravity
> to a little over 1, was used with 5000m (5470 yds)
> in a fixed coil, the lightly-greased turns
> unwinding from the inside like a ball of string
> and paying out through a tube which kept the wire
> clear of the propellors. About 200 were made and
> first issued in the summer of 1944, but results
> were apparently dubious."

The T10 was never intended as a submarine torpedo. Operational torpedoes were fitted with a 5000m wire-coil inside the torpedo. During testing howere, they also tried the system with a 5000m coil on the firingbarrage - also with good results (this was part of the test of determining the practical distance for sending control,signals through a single wire using the sea as return/ground).