Description
The Smoke Float No. 1 Mk IV comprises a cylindrical body, closed at one end by a conical head and a heavy nose. A retarding band is secured to the body adjacent to the head. A tail cone, carrying three vanes to support the vane ring, is secured to the opposite end of the body. The end of the tail cone houses a pistol adapter for the tail pistol, which is locked in place by a grub screw. Inserted in the pistol adapter is a cup, containing a cartridge base and a small quantity of flash composition, sealed with a paper disc. A sleeve leads from the bottom of the pistol adapter into the funnel-shaped upper end of the tube, known as the container cap tube. The container for the smoke composition has a fuzible cup inserted into the top of the smoke composition, which is filled with pressed priming composition. Above this is a layer of loose priming composition, and a primed cambric disc through which is threaded a length of quickmatch. The container is closed by a container cap. A central cylinder, provided with a ring of holes, surrounds the container. The rest of the body and the tail cone comprise a buoyancy chamber. The tail cone is provided with a sinking disc, which is scored, so that if a floating smoke float is found, the disc can be easily pierced to sink the float, the water entering the tail cone and passing into the body through the holes in the central cylinder.
A suspension lug provided on the body permits attachment of the smoke float to a Light Series Bomb carrier.
In the Float No. 1 Mk II, the container cap tube serves only to carry smoke from the container to the sealed hole in the tail cone. A length of safety fuse, giving a 20-sec. delay, extends between the pistol adapter and the container. In the Float No. 1 Mk III, the container cap tube also serves only to carry the smoke from the container to the sealed hole in the tail cone. A separate flash tube guides the flash from the flash composition to the container. The Float No. 1 Mk IVZ differs from the Float Mk IV only in the nature of the smoke composition used.
Should water, especially salt water, come into contact with the smoke composition, it is liable to spontaneous combustion due to chemical action.
Functioning
No information about functioning.
See Also
Nothing else to see.
Source(s)
OP 1665, British Explosive Ordnance (1946)
