HEAD, ROCKET TARGET, 2" MK I

OVERALL LENGTH

DIAMETER

TOTAL WEIGHT

FUZING

TAIL PROPELLING, ROCKET TARGET, 2" Mk I

OVERALL LENGTH

DIAMETER

WIDTH OF FINS

TOTAL WEIGHT

PROPELLANT

PROPELLANT WEIGHT

BURNING TIME

0.45 seconds at 60° F.

GENERAL:

This rocket is designed to give, by means of a flare, a visible aiming mark for anti-aircraft batteries. The target has a range of about 5000 yards at a speed of 250 to 400 knots. The target can be used at night and is suitable for use either aboard ship or ashore.

DESCRIPTION:

Head, Rocket Target, 2" Mk I: The target head consists of a thin sheet metal con-tainer holding a flare candle. Separated from the flare candle by a steel washer is an externally threaded spigot, by which the head in attached to the shell ring of the roc-ket motor. The spigot is fixed to the target head body by means of a double crimp. A weight is fitted into the foreward end of the body and is fixed to the body with 4 screw. A ballistic cap is crimped to the foreward end of the weight.

Four holes are drilled through the body and the weight just foreward of the flare candle, and a similar set of 4 holes is drilled aft of the candle through the body and the spigot. The two sets of holes are covered with a strip of tape 1.5" wide wrapped around the body.

An igniter mechanism, consisting of a diaphragm operated striker, a percussion cap, and a gunpowder charge, is inserted into the after end of the spigot and is held in place by a threaded locking ring.

Tail Propelling, Rocket Target, Mk II: This motor consists of a cylindrical steel body with a shell ring fixed in the foreward end by eight locking pins held in engagement by a circular band spring. Separated from the shell ring by steel washers is an igniter in a moulded cardboard container. Leads from the igniter extend through the central annulus of the cogged cordite grain to four automatic contacts fixed 45 apart on the after end of the motor body. A metal grid supports the cordite grain near the after end of the motor, and a thin metal obturator separated the grid from the venturi. A bag of silica gel is placed in the venturi as a moisture proofing measure.

OPERATION:

Pressure of the gases from the burning cordite propellant grain passes foreward into the spigot of the target head, reversing the diaphragm of the igniter. This forces the striker into the percussion cap and ignites the gunpowder charge, with in turn initiates the flare composition. The flare composition burns slightly, emitting light from the two sets of holes drilled in the body of the target head.

REMARKS:

(1) This rocket motor must not be fired outside the temperature range of -5 to 130° F.

(2) The Mk I Tail Propelling differs from the Mk II only in the dimensions of the cor-dite grain and the type of igniter employed.

(3) Proposed new nomenclature for these motors is "Motor, Rocket, 2", No. 4 Mks I & II".