163. Snowflake Rocket Flares, Fig. 64 are of British design formerly furnished for distribu-tion to U.S. merchant ships to provide illumination for the location of submarines at night. No distribution is being made at present. Each flare furnishes some 300,000 candlepower for approximately 65 seconds at an altitude of 1200 feet, where the flare ingition takes place. The burning flare descends with parachute suspension. The flare is projected from a special projector which is fired either electrically or by percussion. The rocket consists of a tube, 36 inches long and 3.3 inches in diameter. It weighs approximately nine pounds and contains the illuminating element in the head and a propelling charge and stabilizing fins at the base. A canvas skirt extends from the head, part way down the tube. It protects the flare and the projector, when the flare is placed in it, from rain or spray. The skirt is pulled over the outside of the projector, when loading. The propelling charge is of black powder, and the illuminating element is a star of the usual type. After the rocket is fired from the projector, it rises for about six seconds before the expelling charge ejects the star and its supporting parachute. The burning star descends at the rate of approximately 20 feet per second.

Figure 64. – Snowflake Rocket Flare and Projector (Britsh)

Operation

164. Snowflake rocket flare is carried loaded in the special projector provided for it. This projector, weighing 35 pounds, is a tube, fitted with a breech-loading device into which a special cartridge is loaded to ignite the rocket-propelling charge. The tube is fitted into a base plate which is secured to the deck at an angle, to insure a trajectory clear of the ship. The firing angle also prevents the tube and fin assembly of the rocket from falling back on deck when the star and parachute are expelled. The rocket should be fired into the wind, and on most ships two projectors are loaded, so that the one to windward may be used. In order to fire the snowflake rocket, flare, a cartridge is placed in the breech of the projector and the flare itself is slid down the tube from the muzzle. The canvas skirt is draped over the muzzle to keep out rain or spray until the actual firing of the pro-jector. At the command to fire, a pull on the lanyard releases a cocked firing pin and fires the special cartridge in the breech. This ignites the black powder rocket, which raises the flare to 1200 feet, where the star and parachute are ejected and ignited by the ex-pelling charge. The following maintenance provisions should be followed:

(a) Snowflake Rocket Flare should be wiped along its tube with an oily rag, to insure a free fit into the projector tube.

(b) When left in the projector tube, the rocket flare should be raised and lowered in the tube each day until it is fired.

(c) Alight application of Cooper's or similar grease is recommended of the rocket, so that it will not stick in the projector and so that it will repel rain or spray.

(d) The adhesive tape on the rocket head should be kept waterproofed by painting if ne-cessary, and the canvas skirt may also be painted for waterproofing, particularly at its joint on the rocket head.

(e) The special cartridge in the projector should be changed daily to insure positive fir-ing.

(f) Spare snowflake rocket flares should be inspected to make sure that the tape seal at the base is not pierced. If pierced, it should be repaired by gluing on a thin paper patch.

Packing

165. Snowflake rocket flares are packed in wood boxes containing six flares each. It has often been found necessary to straighten fins which have become slightly damaged or bent in transit, or in removing them from the original box. This may be done by tapping the fins back into place. The special percussion cartridges used with the projector are packed in metal cans of then cartridges.

Stowage

166. General rules for the stowage of pyrotechnic ammunition as detailed in paragraphs 9 to 12, inclusive, apply to snowflake rocket flares. Defective or deteriorated flares should be disposed of a stated in paragraph 17.

Safety Precautions

167. The following precautions should always be borne in mind when handling or operat-ing the projector or snowflake rocket flares:

(a) Snowflake rocket flares always head upwind on firing. For this reason the windward projector should be used, if two are aboard the ship.

(b) Rockets which have been exposed to weather over long peridos should be replaced.

(c) The firing lock of the projector loaded with snowflake rocket flares should be left un-cocked until ready for firing.

(d) Rockets of the snowflake type have been kown to ignite prematurely. The operator should stand six to eight feet from the projector when firing, and other personnel in the immediate vicinity should take reasonable cover.

(e) Firing lanyards should be led through tubes and fitted with guards to prevent acci-dental firing of the projector, by tripping over the lanyard.

(f) Care must be taken that the cartridges do not get damp. They should be changed daily, and the retreived cartridges should be wiped dry before being stowed away.