Description
The outer casing of this marker consists of a body and a tail which are connected by a diaphragm. A heavy nose is secured to the body. The nose has a cavity to receive the time valve, and a central hole at the bottom of the cavity which is closed by a transit plug. The valve is a clockwork device which permits the marker to remain in the water for a period up to six hours before it functions. The period of delay is determined by setting the valve before the marker is released from the aircraft. The main filling consists of magnesium-aluminum phosphide, and is packed round a gauze cylinder. Inside the gauze cylinder is a quantity of fast calcium phosphide, which also extends over the top of the magnesium-aluminum phosphide. The main filling is held in place by a thin steel plate having large holes covered by brass gauze, and a large spring anchored to a spring-supporting plate, which abuts against the diaphragm connecting the tail to the body of the weapon. A layer of charcoal is provided beneath the steel plate to absorb any small quantities of phosphine gas generated by traces of moisture which may be in the body of the marker during filling, and a layer of glass wool beneath the charcoal which acts as a dust filter. The tail constitutes a buoyancy chamber, and a main outlet tube extends between the diaphragm and a tail cap at the outer end of the tail.
When breaking the rupture disc, do not hold the head directly over the tail cap of the marker. This avoids possible injury to the eyes which might be caused should sufficient pressure be built up in the marker to force phosphide dust particles past the glass wool filter at the top of the main filling.
Functioning
No information about functioning.
See Also
Nothing else to see.
Source(s)
OP 1665, British Explosive Ordnance (1946)
