OVERALL LENGTH

MAX. BODY DIAMETER

TOTAL WEIGHT

FILLER

BURNING TIME

COLOR

DESCRIPTION:

Consists of a body with a steel nose at one end having a central hole closed by a stopper which forms part of a thin bakelite disc secured to the nose by screws. The disc is protected during transit and storage by a nose transit cover held in position by adhesive tape. The tail constitutes a buoyancy chamber, and a main outlet tube ex-tends between the diaphragm and a tail cap at the outer end of the tail. The tail cap has a neck closed by a thin rupture disc to which is secured a small pillar having a ring attached to it. Two locating pieces secured to the outside of the body are provided to locate a suspension band in position if the marker is to be carried on a Light Series Bomb carrier.

FUNCTIONING:

When it is dropped into water, the bakelite disc is broken by impact with the water, the stopper falls away and the marker rises to float on the surface. Water enters the central hole in the nose and, after passing through the gauze thimble, some of it soaks through the flannel washer, passes through the small hole in the valve body, and enters the brass tube after soaking through the flannel washer in the tube. The remainder of the water passes through the water inlet tube, percolates through the open-mesh me-tallic cylinder and its flannel sheath, and enters the body of the marker. The brass cap prevents water from passing through the sheath and coming into direct contact with the calcium phosphide. The water which enters through the nose reacts with the mag-nesium-aluminum phosphide and gives off pure phosphine, which is not spotaneously inflammable. Some water, however, passes down the main outlet tube while the marker is submerged, and this water reacts with the calcium phosphide to produce a phosphine which, in contact with the air, is spontaneously inflammable. The supply of spontan-eously inflammable gas lasts only about 3 minutes and is thereafter maintained by the phosphine evolved from the magnesium-aluminum phosphide mixing with the gaseous oxides of nitrogen given off by the inter-action of the potassium bisulphate and the sodium nitrite, which are dissolved by some of the water which enters through the nose.