Description
The bomb consists of a thin tin plate can of square cross section, to one face of which are soldered two corrugated stiffeners, which serve to increase the strength of the can and also act as distance pieces between the can and the drop bar of the 250 lb. Small Bomb Container. A burster container, to take the Fuze No. 854 Mk I and its burster, and an offset filling hole are provided in the top of the can, together with a large circular distance piece.
The burster container is closed, during transit and storage, by a rolled-thread tin plate, transit plug. The filling hole is permanently sealed by a rolled-thread filling-hole cap, seating on a sealing disc. This cap must in no circumstances be unscrewed from the bomb; and, as it is fitted with a short Tommy bar, it may be readily distinguished from the transit plug.
Three handles for lifting the bomb are provided, and at two diagonally opposite corners of the can are soldered metal loops for the attachment of a fabric tail, which acts as a stabilizer to the bomb.
These bombs are carried three in a 250 lb. Small Bomb Container. In the container, they are separated from each other by the distance pieces on the end of each bomb.
The Bomb Mk II is similar to the Mk I in operation, differing only in the following minor structural details. The filling hole is centrally located in the top of the can. Two small distance pieces are provided at the top of the can and are located at diagonally opposite corners, on either side of the filling hole. The two metal loops to which the fabric tail is secured differ slightly in design from those used on the Bomb Mk I.
These bombs have a burning time of 15-20 minutes and provide an effective screen 250-300 yd. in length. They are dropped from aircraft to produce smoke screens for covering land operations.
Functioning
On impact of the fuzed bomb with its target, the “all-ways” action fuze functions instantaneously. The explosion of its burster disrupts the bomb and scatters the white phosphorus filling, which, on contact with the air, ignites spontaneously and begins to give off smoke.
See Also
British Bombs - Designation and Classification
Source(s)
OP 1665, British Explosive Ordnance (1946)
