American Projectiles and Explosives - Submarine Pyrotechnics

American Projectiles and Explosives

Shipboard Pyrotechnics

Submarine Items

Submarine Float Signal Mk 1 Mod 1 and Mk 2 Mod 0

Length: 18.75 inches
Diameter: 3 inches
Delay: 27 seconds
Burning time: 15 seconds

Color: Black, Yellow, Green, or Red


Use: These float signals are used to mark the position of a submerged submarine, and for other marking purposes.


Description: The firing mechanism consists of a firing pin, firing-pin spring, firing-pin lever, and tripping lever or lug.  The ignition system consists of a primer, time fuse, quick match, and a starter mixture.  The aluminum signal contains a smoke pot, smoke mixture, smoke pot cover, and central tube.  The signal has a nose cap and release valve.


Operation: The signal is fired from a submerged submarine, through a tube, using compressed air as a propellant.  As the signal is leaving the ejector, a tripping lever is raised by contact with a lug in the gun, cocking and releasing the firing-pin lever, which fires the primer.  The primer ignites the time fuse, which burns for 27 seconds.  The signal is buoyant and rises to the surface within the 27 seconds of fuse delay.  The time fuse ignites a piece of quick match, which, in turn, initiates the starter composition.  The starter composition sets off the smoke mixture.


Remarks: The maximum launching depth is 162 feet.

The Submarine Float Signal Mk 2 Mod 0 is similar to the Mk 1 Mod 1, except for a fixed delay of 54 to 59 seconds, a maximum launching depth of 285 feet, and sturdier construction.

Submarine Emergency Identification Signal Mk 2 Mods 1 and 2; also Submarine Emergency Signal, Star, Mk 3 Mods 0 and 1

Length: 18 inches
Diameter: 3 inches
Burning time: 25 seconds
Delay: 27 seconds

Color of star: Red, Yellow, or Green


Use: These signals are used for submarine emergency identification, whether submerged or surfaced.


Description: The signal consists of a cylindrical aluminum case containing the grenade-type Pyrotechnic Candle Mk 3.  The bottom end contains two delay elements.  A single-star candle is attached to a parachute by an asbestos cord.


Operation: The shell is projected from the standard submarine emergency identification signal ejector, using compressed air as the propellant.  The shell is fired by a lug at its base which projects beyond the side of the shell and rides in a groove in the ejector tube.  As the shell is forced through the tube, the extended lug reaches the end of the groove just before the base of the shell passes the muzzle door.  The tripping lever is pulled back, thereby cocking and releasing the firing pin lever and firing pin.  The firing pin strikes the primer, and the flash from the primer ignites a time fuse.  The time fuse burns while the signal is rising to the surface.  The delay ignites the grenade-ejection charge, which ejects the signal to a distance of approximately 250 feet.  At the summit of the trajectory, the delay train flashes into the signal-ejection charge and causes the parachute-suspended star to be ejected.


Remarks: The Mk 2 Mod 2 is obsolescent, being replaced by the Mk 3 Mods 0 and 1.  The Mk 3 Mod 0 has a slightly different method of expelling the inner grenade.  The maximum launching depth is 160 feet.

The Mk 3 Mod 1 is similar tot he Mk 2 Mod 1, except for the following:
-A delay of 54 to 59 seconds,
-A maximum launching depth of 285 feet, and
-A sturdier construction to withstand pressures at a lower depth






Pistol Rocket Signal Mk 1, Comet; Mk 3, Shower; and Chameleon

Length: 14 inches
Diameter: 1.5 inches
Burning time: 1 seconds
Intensity: 60,000 candlepower

Color of single star: Red, Yellow, or Green


Use: These signals are used for emergency identification by surfaced submarines.


Description: The upper section or signal chamber contains a pyrotechnic composition and powder-ejection charge.  The rocket motor, which is riveted to the signal chamber, contains one gram of black powder above a felt washer and 58 grams of black powder, which is the rocket element.  Four spring-loaded hinged vanes, four inches long and one inch wide, are attached to the rocket tube and fold and fit into the rocket chamber.  The rocket chamber is an aluminum container with a Primer Mk 5 in its base.  This unit receives the rocket motor.


Operation: The signal is fired from the submarine rocket pistol or the Pyrotechnic Pistol AN-M8.  Release of the trigger fires the primer, which ignites the one-gram auxiliary propelling charge.  This black-powder charge propels the signal chamber and attached rocket motor to about 30 feet from the pistol muzzle.  At this point the 58-gram charge of black powder, which is the rocket element, takes effect and propels the signal to a height of approximately 650 feet.  The rocket element ignites the expelling charge at the zenith of its trajectory.  The expelling charge ignites the star and simultaneously ejects it.  The single star falls freely, and burns out just before hitting the water.


Remarks: This signal replaces the chameleon-type submarine rocket signal.

The Rocket Pistol Signal Mk 8 Mod 0 (Shower) is similar to this signal, except that a burst shower is produced instead of a single star.

The Rocket Pistol Signal, Chameleon, is similar to this signal, except that a variety of colors is obtained.

Submarine Emergency Identification Flares Mk 10 Mods 0-2, Mk 11 Mods 0-2, and Mk 12 Mods 0-2

Length: 9.75 inches
Diameter: 2 inches
Weight: 3.2 pounds


Use: These signals are used by surfaced submarines to identify themselves.


Description: The flare case consists of a seamless steel tube, one end of which is closed by a steel closure disc.  The firing mechanism, which extends along the side of the flare body, is attached tot he base casting, which carries the closure disc and primer.  The firing mechanism is enclosed in a brass housing which contains the following: (1) a brass shaft held in place by a cotter pin, (2) a firing pin attached to the brass shaft by a sear join, (3) a spring surrounding the firing pin, and (4) a lanyard attached to the brass shaft.  The flare case contains the following: (1) a black-powder charge, (2) a starter composition, (3) a pyrotechnic charge, and (4) a steel cup riveted to the case, closing one end.  Two clamps are welded to the flare body for mounting on the bracket, fixed to the submarine bridge.

Operation: Mount the flare so that the firing mechanism points toward the deck.  A vertical pull on the lanyard forces the brass shaft up, compressing the firing-pin spring.  The sear joint between the shaft and firing pin is broken when the shaft is pulled approximately 0.5 inches.  The firing pin strikes the primer, which ignites a small charge of black powder.  The flash from the black powder ignites the starter composition, which, in turn, ignites the pyrotechnic candle.  The flare burns in four increments of 10 seconds duration and intervening blackout increments of five seconds.



Remarks: Flares that have been submerged below periscope depth should be thrown overboard at the first opportunity.

 The possibility of detonation in any of the flares, and particularly in those with green pyrotechnics, should never be lost sign of.  For this reason, personnel in the vicinity of the flares should be adequately shielded prior to firing.

Submarine Emergency Identification Flares Mk 10 and Mods are similar to the Flares Mk 11 and Mods and Mk 12 and Mods, except that these burn with only one uninterrupted color - Mod 0, red; Mod 1, green; and Mod 2, yellow.

False Target Shell Mk 1 Mod 0

Length: 18 inches
Diameter: 3 inches
Delay: 27 seconds
Persistence of echo: 4 to 18 minutes


Use: This shell is used to confuse and disrupt enemy underwater echo ranging.


Description: The external appearance is similar tot he Submarine Emergency Signal Mk 2 Mod 2.  The shell holds six metal cups 2.75 inches in diameter and 1.875 inches in depth, filled with a lithium hydride paraffin mixture.  The base of the shell contains a primer, time fuse and 20-gram charge of smokeless powder.  Attached tot he base is a firing mechanism which is used with the standard emergency identification signal ejector.


Operation: The shell is projected from the standard emergency identification signal ejector, using 200 pounds per square inch air pressure if possible.  The shell is fired by a lug at its base which projects beyond the side of the shell and rides in a groove in the ejection tube.  As the shell is forced through the tube, the extended lug reaches the end of the groove just before the base of the shell passes the muzzle door.  The tripping lever is pulled back, thereby cocking and releasing the firing pin lever and firing pin.  The firing pin strikes the primer, and the flash from the primer ignites a length of time fuse coiled in the base of the shell.  The time fuse burns for 27 seconds, and then ignites the 20-gram charge of smokeless powder, which ejects the six cups of lithium hydride.  When the lithium hydride touches the water, a chemical reaction occurs which yields fine hydrogen bubbles.  The hydrogen bubbles return an echo of the same order and magnitude as that returned by a submarine.


Remarks: False target shells should be segregated from pyrotechnics and other ammunition components, and should be kept in a dry atmosphere.

When visibility is such that surface disturbance may be a hazard, false target shells should not be released from depths less than 150 feet, because small bubbles or a surfaced canister may result.

False Target Can Mk 2 Mod 0

Length: 19.3 inches
Diameter: 3 inches


Use: False Target Can Mk 2 Mod 0 has the same use as False Target Shell Mk 1 Mod 0.


Description: Generally similar tot he False Target Shell Mk 1 Mod 0, this can is a tube of sheet steel sealed at both ends, containing nine metal cups filled with a lithium hydride composition.  These cups can be released individually at any desired rate when used with the new hydraulic-type air-operated signal ejector.  The cups are separated by aluminum discs, and a one-inch metal spacer separates the end caps of the outer tube from the top and bottom inner cups.  Tear strips are provided at either end to open the can.


Operation: The tear strips, the end caps, the spacers on either end, and the corrugate paper disc at the top end are removed, with the can in a horizontal position to prevent dropping one of the cups.  Insert one end into the breech of the ejector about one inch.  Put a rammer int he other end of the can and push the cups toward the muzzle of the ejector, until the spring detent near the top of the barrel drops behind the last cup.  Remove the empty tube.  Place the firing valve on "Vent". Close the breech door and flood the barrel from the sea through the flood line, allowing air to escape through the vent line.  When no air escapes the vent or firing valve, close these valves and open the muzzle door.

Make the pressure in the volume tank 50 pounds greater than sea pressure, and through the firing valve into the "Fire" position.

Signal (Pepper) Mk 14 Mods 0-2 (Production Suspended)

No picture available

  

Length: 27.5 inches
Diameter: 3 inches
Weight: 19 pounds (approximately)


General: The Signal (Pepper) Mk 14 is an expendable explosive noisemaker for underwater use.  It consists of a series of aluminum discs, each of which has sixteen small explosive charges around its periphery.  Each disc contains a gas-less fuse train which ignites the charges at one-half second intervals and then communicates the ignition to the succeeding discs.  Approximately five minutes of noise can be produced.  Parachute suspension is used to retard the sinking rate.  A firing device ignites two delay-fuse trains.  The initial delay train ignites the first of the explosive discs, and the secondary delay train fires a small black-powder charge which ejects the parachute.  The Signal (Pepper) Mk 14 is supplies as Mods 0, 1, and 2, having 30-second, 2-minute, and 6-minute initial delays respectively.  Mods 0, 1, and 2 are identical, except that one explosive disc in Mod 1, and two in Mod 2, have been replaced by initial time-delay discs.  The effective firing time is the same in all three Mods, for practical consideration.

Tests on the initial production of this device show that about 75% of the units may be expected to operate to completion.  It is recommended that, wherever possible, two or more units be fired in quick succession to insure functioning.


Description: The signal consists of the following components: firing device, initial time delay, secondary time delay, a stack of explosive-loaded discs, a center connecting tube and end discs to support the explosive stack, a parachute knock-off charge, parachute assembly, and packing container.

The firing device is identical in operation to the firing device used on the Submarine Emergency Identification Signals.  It consists of a support, firing lever, tripping lever, safety pin, and safety cotter pin.  When the safety cotter pin is pulled, it allows the safety pin to be forced back by its spring, releasing the tripping lever.  On ejection, the tripping lever is forced back by the end of the tripping groove.  The tripping lever lifts the firing lever against the firing spring and then releases it to fire the primer. The primer ignites both the initial and the secondary time delays.

The initial time delay is a pyrotechnic fuse train from the primer tot he first of the explosive capsules.  It has the approximate times as follows:

-Mod 0: 30 sceonds

-Mod 1: 2 minutes
-Mod 2: 6 minutes

The secondary time delay is a pyrotechnic fuse train from the primer to the parachute knock-off charge.  It is approximately five seconds for all three Mods, starting from the time of ejection.

The explosive stack consists of a series of aluminum discs three inches in diameter and one-half inch thick.  Each disc has sixteen small explosive-loaded capsules inserted radially around the periphery.  The capsules are connected by an internal ring fuse train which is timed to fire the charges at the rate of two shots per second.  The number of explosive discs in the stack varies with each Mod as follows:

-Mod 0: 37
-Mod 1: 36
-Mod 2: 35

A center connecting rod and end discs support the explosive stack.  The secondary delay and parachute-ejection charge are located int he center tube.  The parachute assembly, chute packed in a can which is split open by the ejection charge, is screwed onto the end opposite the firing device.


Ejection: The signal may be ejected from either the hand or the new hydraulic air-operated ejector at any depth.

Next Time: Hand Grenades (Part 1)

American Projectiles and Explosives - Shipboard Pyrotechnics

American Projectiles and Explosives

Shipboard Pyrotechnics

Surface Vessel Items

Distress Smoke Hand Signal AN-Mk 1 Mods 0 and 1

Length: 3.875 inches
Diameter: 1.625 inches
Weight: 0.37 pounds


Description: The signal is encased in a metal cylindrical body, one end of which is closed by a soldered cap and pull ring.  The case can be held comfortably and safely in the bare hand during the burning period.  The signal contains a pyrotechnic smoke mixture and is watertight.


Operation: The sealing tape around the end of the cylinder is torn off and the paper cap is removed.  The pull ring is brought down over the rim of the can and pressed down, using the ring as a lever to break the seal.  The cylinder is pointed away from the face; and a quick pull is exerted on the pull ring, which comes out of the can, thereby igniting the smoke mixture.  The signal should be held at arm's length at an angle of about 30 degrees, so that drippings will not fall on the hand.


Remarks: This signal is to replace the White Smoke Grenade, H.C., AN-M8, for emergency kits in life rafts and aircraft.

Signal, Distress - Day and Night - Mk 13 Mod 0

Length: 5.12 inches
Diameter: 1.62 inches
Weight: 6.4 ounces


General: Adapted for both day and night use, Hand Signal Mk 13 contains both the orange smoke canister for daylight and a flare pellet, for darkness.  Like the Smoke Signal AN-Mk 1 in appearance and operation, the Signal Mk 13 is small and is easily stowed in life-vest pockets, flight suits, or life rafts.


Description: The metal outer case is closed at both ends by a soldered cap to which is attached a pull ring.  Removing the soldered cap pulls a brass wire attached to its bottom through a cup coated with a friction igniting compound.  Depending on whether the "day" or "night" ring is pulled, the two ends of the case being distinctly so marked, the smoke mixture or the flare is ignited.  Smoke emission time is 18 to 20 seconds.  The average candlepower of the flare is 3,000 candles.  Paper cups cover the pull rings on each end of the signal.


Operation: After the paper cup is removed from desired end, a quick pull is given on the ring.  If the soldered cap fails to come off, bring the pull ring down over the side of the can, and use the ring as a lever to break the seal.  Hold the signal at arm's length and 30 degrees elevation while burning.  After one end is used, the signal should be doused in water to cool the metal parts.  It should then be retained for possible use of the other end.  Each end is insulated and waterproofed from the other.


Remarks: Both ends of the Signal Mk 13 should never be ignited at the same time.






Navy Red Light Mk 1 and Navy Blue Light Mk 1 Mod 1

Length: 12 inches
Diameter: 1.25 inches

Burning time (Blue): 1 to 1.5 minutes
Burning Time (Red): 2.5 to 3 minutes


Description: The flare consists of a paper tube filled with a pyrotechnic composition and attached to a wooden handle.  The top of each flare contains a button of ignition material.  A friction striker is provided with each signal.


Operation: The flare is ignited by scraping the top of the inside cap against the forward end of the pyrotechnic mixture.  Hold the flare in an inclined position while burning, to prevent drippings from burning the hand.

Ship's Emergency Identification Signals Mks 1-4

General: The body of each of these signals varies in length according to its design.  Each signal consists of a pressure-retaining disc and disc-locking nut, a primer, a four-gram smokeless-powder propelling charge, a copper obturating cup, a delay train, an ejection charge of approximately 1.1 grams of black powder, and a signal of pyrotechnic composition.  All signal cups except the shower signals have a parachute for mid-air suspension.


Operation: The signal is fired from Signal Projector Mk 1 or Mk 1 Mod 1.  The signal is placed in the projector primer-first, where it rests against the retaining pin.  A pull on the lanyard removes the firing pin and allows the signal to descend against the firing pin with sufficient force to close the valve and fire the primer.  The primer ignites the delay train and propelling charge simultaneously.  The gases from the propelling charge expand the obturating cup until it is secured tightly in the bore of the projector.  Increased pressure ruptures the pressure-retaining disc, and the gases then escape through the openings in the retaining-disc locking nut into the projector bore.  The gases propel the signal approximately 600 feet.  The ignited delay train burns until the signal reaches approximately the zenith of its trajectory, and then ignites the ejection charge.  The ejection charge ejects and ignites the signal pyrotechnics through a quick match and first fire composition

Mk 1 (Star)

Length: 5.124 inches
Diameter: 2.49 inches
Color: Red, white, green, or yellow
Burning time: 25 ±5 seconds

The closing cup is embossed for night identification.  The star is parachute suspended.

Mk 2 (Shower)

Length: 6.374 inches
Diameter: 2.5 inches
Color: Red, white, or green
Burning time: 5 seconds

This signal is designed to give two distinct bursts, one with a short delay and one with a long delay.  The closing cup is embossed for night identification.

Mk 3 (Smoke)

Length: 9.124 inches
Diameter: 2.49 inches
Color: Red, black, green, or yellow
Burning time: 25 ±5 seconds

The closing cup is embossed for night identification.  The star is parachute suspended.


Mk 4 (Chameleon)

Length: 5.124 inches
Diameter: 2.49 inches

Color Combinations:
Red-green-white
White-red-green
Green-white-red


Burning time for each color: 9 seconds
Delay between colors: 1 second

The signal is parachute suspended and designed to change color while burning.  Otherwise, the signal is similar to the Signal Mk 1.

Float Flare Mk 15 Mods 0 and 1

Length: 37.2 inches
Diameter: 6.5 inches
Weight: 26 pounds
Burning time: 5 minutes
Intensity: 100,000 candlepower
Delay before ignition: 5 minutes


Use: Float Flare Mk 15 Type is used by PT boats in illuminating enemy ships.


Description: The flare consists of a wooden body housing a pyrotechnic column and having a metallic base to provide flotation stability.  The top of the flare is closed by a cone-shaped adapter which contains a bouchon grenade-firing mechanism attached to a celluloid disc.  Enclosed is a 3.5-foot length of time fuse.  The starter composition is attached tot he flash end of the time fuse.  The illuminant composition is next to the starter composition.


Operation: The flare is held horizontally, with the right hand firmly grasping the bouchon lever and the left hand supporting the nose cap.  The safety key is pulled and the flare is tossed overboard.  When the bouchon lever is released, the firing pin is forced by the firing-pin spring to impinge upon the primer.  the primer ignites the time fuse.  The time fuse flashes into a booster bag of starter composition, which, in turn, ignites the flare.


Remarks: It is recommended that one man hold the flare while a second man pulls the safety ring.

 Mod 1 is like the Mod 0, except that it has a mechanical clockwork timing device, for settings from one to 30 minutes, instead of the time-fuse device.

Rocket, White, Marine Type, Mk 1 Mod 0

Length: 12 inches
Diameter: 1.5 inches
Weight: 2 pounds
Burning time: 5 seconds


Use: This is a merchant marine rocket issued by the Navy


Description: This rocket signal consists of the rocket body, star pellets, propelling charge, clay heading, and closing cap.


Operation: The rocket is fired by the Pyrotechnic Pistol AN-M8 and reaches a height of 250 feet.  At the height of its trajectory, the rocket bursts.  The falling particles burn for five seconds.


Remarks: This signal will be replaced by the Rocket Pistol Signal Mk 3 Mod 0 (Shower).

Next Time: Submarine Pyrotechnics

American Projectiles and Explosives - Ground Pyrotechnics (Part 3)

American Projectiles and Explosives

Ground Pyrotechnics

Flares

Parachute Trip Flare M48

Diameter of flare tube: 2.5 inches
Height of trajectory: 300-500 feet
Burning time: 20 seconds
Intensity: 100,000 candlepower
Effective Illumination: Circle of 800 yards radius

Color: White to Yellowish


Use: The flare is used to give warning of enemy marauders or infiltrating hostile troops; also, for illumination or signaling.


Description: The flare consists of a 1/4-inch pipe and a steel tube approximately 2.5 inches in inside diameter, which are attached to a base plate that contains a 75-grain propelling charge.  The steel tube contains a delay fuse, an expelling charge, a candle, and a parachute assembly.  The 0.25-inch pipe and the firing mechanism are joined by a coupling, and the pipe is threaded to the base plate.  The firing train is composed of a primer, an igniter, and a relay charge.  The firing mechanism contains the pressure cap, pull ring and pin, safety screw, safety cotter pin, and spring-loaded firing pin.


Operation: A 20- to 30-pound pressure on the pressure cap or a tension of four to six pounds on the pull pin releases the firing pin and fires the primer.  The primer initiates the igniter, which, in turn, starts the relay charge.  The relay charge sets off the propelling charge, which projects the illuminating shell through the large steel tube to a height of 300 to 500 feet.  The propelling charge ignites a three-second delay fuse in the shell.  The delay fuze ignites an expelling charge which expels a parachute-supported candle from the shell.

Trip Flare M49

Length: 3.8 inches
Diameter: 2.5 inches
Burning time: 1 minute
Intensity: 40,000 candlepower

Color: White to Yellowish


Use: The Trip Flare M49 has the same uses as the Parachute Trip Flare M48


Description: The flare has a grenade-shaped cylindrical body, with a nose fuze that protrudes 0.875-inch from the head end.  A mounting bracket and a spring-loaded trigger mechanism are mounted on a metal base cap.  The upper arm of the trigger is attached to a trip wire, and the lower arm of the trigger restrains the safety lever after the removal of the safety pin.


Operation: A pull on the trip wire rotates the upper trigger arm away from the fuze lever.  If the trip wire is cut, the upper trigger arm, which is restraining the fuze lever, rotates away from the fuze lever but in an opposite direction from above.  A grenade-type fuze is used, but is has no delay element.  The fuze ignites the flare simultaneously.





Trip Wire Flare Mk 1 Mod 0

Length of tube: 5.5 inches
Diameter of tube: 2.5 inches
Weight: 3.5 pounds
Burning time: 65 seconds
Candlepower: 100,000
Effective illumination: Area 500 feet in diameter


Use: The purpose of the flare is to reveal the approach of enemy troops.


Description: The flare case is a steel tube approximately 5.5 inches long and 2.5 inches in diameter.  Fixed to one end is a pull-type, spring-actuated firing mechanism to which the trip wire is attached.  Enclosed in the tube are the primer, black-powder charge, impregnated muslin disc, and pyrotechnic composition.  Two 40-foot lengths of wire are available, making it possible to have two trip wires running in opposite directions.  A web belt secures the flare to a tree.


Operation: A tug of three pounds or more on the trip wire draws the plunger and firing pin away from the primer and compresses a spring which surrounds the firing pin.  As the plunger is pulled away from the firing mechanism, its notched end disengages from that of the firing pin, which is then forced against the primer by the compressed firing-pin spring.  The primer ignites 0.3 grams of black powder.  The black powder ignites the impregnated muslin disc, and in turn the pyrotechnic composition.  The resultant gas pressure blows out the closure disc from the head, and the flame from the burning candle illuminates the surrounding area.  White smoke given off by the flare does no interfere with the effectiveness of the illumination.


Remarks: To prevent self illumination, the flare should be mounted about 125 yards before friendly positions.  While mounting the flare, personnel should wear steel helmets, and heads should be kept below and away from the top of the flare.





Ground Flare M81-M83

No picture available

Length (w/o spike): 7.75 inches
Diameter: 1.75 inches
Weight: 0.88 pounds
Burning time: 2 minutes

Color and Intensity:
-M81: Red - 20,000 candlepower
-M82: Yellow - 25,000 candlepower
-M83: Green - 35,000 candlepower


Use: The flare indicates, to cooperating air elements, a line of position or direction.  It is also used for troop-recognition purposes.


Description: The flare consists of a paper cylinder containing a pyrotechnic composition.  It has a wooden base block with a 20-penny spike through it, and a match head covered by a removable metal cap, under which lies a wooden disc.  A plastic film seals the metal cup to the flare body.  The outer head of the wooden disc has the scratching surface required to ignite the match composition.


Operation: The flare is stuck in the ground with the spike as a support.  The plastic seal is pulled off and the wooden disc scratched against the match composition, which ignites the flare.


Remarks: These ground flares are not procured by the Navy at present.

Target Rocket Flare Mk 1 Mod 0

Weight: 3 pounds


Use: The Target Rocket Flare Mk 1 Mod 0 is used with the 3.25-inch Rocket Targets Mk 10 and Mk 11.


Description: A pyrotechnic candle, secured into a wooden body, is housed in a steel tube.  An electric squib is located over the starter composition of the candle.  A steel cup shields the ignition end of the flare, and squib leads are coiled inside the nose cap.


Operation: Tear off the adhesive strip and remove the cover.  Place the flare over the nose of the rocket, and uncoil the squib leads.  Fasten the alligator clips to the cotter pins of the leads, and fire.





Airport Flare M13 (Obsolete)

No picture available

  Length: 23.1 inches
Diameter: 1.75 inches
Intensity: 40,000 candlepower
Burning time: 3 minutes


Use: Airport Flare M13 is used to provide illumination for airplane landing at emergency fields, and to illuminate targets and objectives.  A further use is to prevent infiltration or surprise by enemy troops.


Description: The flare consists of a cylinder; the top cover sealed with a strip of adhesive tape, and a seven-inch hollow chip-board tube mounted to one end of the cylinder.


Operation: Remove the adhesive tape and slip the hollow tube over a rod stuck in the ground.  Pull on the lanyard attached to the ignition wire to fire the flare.


Remarks: This flare is not procured by the Navy.

Airport Flare M76

No picture available

  Length: 32 inches

Diameter: 6 inches

Intensity: 800,000 candlepower

Burning time: 6.5 minutes

Use: Airport Flare M76 is used to indicate the end of a runway in a fog.

Description: This flare consists of a cylinder containing a candle similar to, but larger than, the candle of the Flare AN-M26.  The cylinder is fitted with a socket base arrangement into which four channel-shaped legs may be inserted to hold the flare upright on the runway.

Operation: The flare may be initiated by the use of the electric squib or by pull on the release fork which allows the spring-loaded firing pin to strike the primer.  The primer acts directly to ignite the first fire composition.

Remarks: Airport Flare M76 is not procured by the Navy.

High-Altitude Parachute Mortar-Fired Flare Mk 20 Mod 0

No picture available

  Length: 10.75 inches

Diameter: 2.5 inches

Weight: 5 pounds

Height of trajectory: 1,000 feet

Intensity: 85,000 candlepower

Color: White

Burning time: 60 seconds

Rate of fall after ignition: 16 feet/second

Use: This high-altitude flare is used to illuminate seaplane landing areas at night, and to illuminate an island base when low ceilings do not permit proper visibility from normal flying levels. 

Flare: The flare consists of a cylindrical steel tube body with a copper cup welded to the closed tube body with a copper cup welded to the closed end of the tube.   The body contains an expelling charge, a pyrotechnic candle, and a silk parachute.  The copper cup contains a fuse assembly, a propelling charge, 25 grams of a combination smokeless powder and black powder, and a standard shotgun primer.

Mortar: The mortar consists of a steel tube 36 inches long and 2.8 inches in diameter.  The tube is screwed into a steel base plate 0.75 inches thick and 12 inches square.  The base plate is provided with a central stud into which is pressed a hardened steel firing pin.

Operation: Remove the closing cap from the end of the mortar.  Attach a 30-foot lanyard to the brass release pin and insert the pin in the two holes drilled transversely about six inches from the end of the mortar.  Insert the flare into the mortar so that it rests on the release pin, with the copper end down.  Fire the flare by pulling the lanyard, thus removing the release pin.  The flare falls to the bottom of the mortar, firing the primer.  The primer sets off the propelling charge and ignites the delay fuse.  the expanding gases force the copper cup away from the flare and fill the bore of the mortar.  The flare is propelled 1,000 feet into the air, at which time the delay fuse ignites the expelling charge.  The pyrotechnic candle and parachute are expelled, the expelling charge igniting the candle.

Remarks: A suitable barrier should be erected to shield personnel firing the flare.  In case of a misfire, wait at least three minutes before disassembling the mortar.  Clean mortar tube after firing.

Next Time: Shipboard Pyrotechnics

American Projectiles and Explosives - Ground Pyrotechnics (Part 2)

American Projectiles and Explosives

Ground Pyrotechnics

Launcher Type M17A1 - M22A1; M51A1; M52A1; and M17A1B2 - M22A1B2

Length: 10.5 inches
Diameter: 1.6 inches
Delay: 6 seconds
Height of trajectory: 600 feet


Description: The signal is assembled in a cylindrical case and equipped with a finned tail assembly for stabilization purposes.  It is similar to the projector type, but modified to be fired from a service rifle or carbine.  This type has a hollow stem, which is closed by a cork plug and a wheel-shaped fin.  The "A1B2" series is the same as the "A1" series, except that the former indicates steel construction.  Special cartridges are used to ignite the propelling charge.  Embossed letters on the closing cap indicate color and type of star(s).


Operation: Remove the cork plug from the tail and place the signal on a rifle launcher.  Place the butt of the rifle on the ground as far away as practicable.   When the rifle is fired, the cartridge fires the primer, which in turn ignites the propelling charge.  The signal travels approximately 100 feet and then reverses itself and reaches an altitude of approximately 600 feet.

High-Bursting Range Signal M27A1B1

No picture available

Length: 8.37 inches
Diameter: 1.5 inches
Weight: 9.25 ounces
Height of trajectory: 700 feet


This signal has the standard tube and fin assembly as the launcher types.  It is used in training maneuvers to simulate the air burst of an artillery shell.  It produces a flash and puff of smoke, and a noise audible for at least 2,000 yards.






Flash and Sound Signal M74

No picture available

General: The Flash and Sound Signal M74 is designed for simulation of air burst of artillery fire in training troops.  It is fired from the Hand Projector M9 or the Pyrotechnic Pistol AN-M8


Description: The signal consists of an outer case, an expelling charge, and an inner cylindrical case containing the delay fuze and bursting charge.  The outer case resembles those of the aircraft double-star type.  A percussion primer in the base of the outer case extends into the expelling charge.  The expelling charge sets off the delay fuze.


Operation: When fired, the primer ignites the expelling charge.  This ignites the delay fuze and propels the inner case out of the outer case.  After a delay of about two and a half seconds, the fuze ignites the burster charge which, in exploding, produces a bright flash and a loud noise.


Remarks: With the pistol or projector at 45 degree elevation, the signal will reach a height of about 100 feet for its burst.  Helmets should be worn by exposed personnel.





Smoke Signals M62, M64, M65, and M66

Length: 10.15 inches
Diameter: 1.88 inches
Bursting altitude: 600 feet

Colors:
-M62: Red
-M64: Yellow
-M65: Green
-M66: Violet


Use: These signals are employed by artillery observes to signal or lay in a line of fire.


Description and Operation: The signal is launched in the same manner as the M17A1 series.  The fuze delay ignites an expelling charge, which expels and ignites the six smoke pellets at an altitude of 600 feet.  The pellets burn and fall, leaving a colored smoke trail.

Pistol Rocket Signals Mk1 Mod 2 and Mk 2 Mod 1

  Length: 14 inches
Diameter: 1.5 inches
Burning time: 21 seconds
Weight: 1 pound


Use: These signals are for identification on other signalling between ground troops.


Description: Similar in construction to the submarine signal, Pistol Rocket Signal Mk 1 Comet, the Pistol Rocket Signal Mk 1 Mod 2 produces a chameleon signal consisting of three parachute-borne stars which burn successively in three colors.  Each star burns for approximately seven seconds before the next color ignites.  The Pistol Rocket Signal Mk 2 Mod 1 is a smoke signal, a parachute-borne smoke candle, but is generally the same construction as the Mk 1 Mod 2.

Operation: The signals are fired from the Submarine Rocket Pistol Mk 1 Mod 0 or the Pyrotechnic Pistol AN-M8.  The primer ignites the one-gram auxiliary expelling charge, which projects the upper section of the signal to a height of 30 feet, where the rocket powder ignites, sending the signal on up to 650 feet.  There the pyrotechnic element, chameleon or smoke, ignites.  As the signal leaves the projector or pistol, the spring-loaded vanes fold out into place, stabilizing the flight of the signal.





Illuminating Hand Grenade Mk 1

  Length: 4.3 inches
Diameter: 2.1 inches
Weight: 9.2 pounds
Intensity: 60,000 candlepower
Delay: 7 seconds
Burning time: 25 seconds


Description: The grenade consists of two metal shells pressed together and sealed.  The upper shell contains a Bouchon igniter and a delay fuse.  The bottom shell contains the illuminant composition, first fire charge, ignition charge, quick match, and disc.


Operation: Pull the release pin and throw the grenade.  When the lever is released, the firing pin is freed to fire the primer.  The primer ignites the delay fuse, which burns for seven seconds and then ignites the ignition charge.  The ignition charge sets off the first fire composition, which in turn ignites the illuminant composition.  The gases from the ignition charge and first fire force the two shells apart, thus leaving the illuminant composition of the bottom shell free for burning.

Next Time: Ground Pyrotechnics (Part 3)

American Projectiles and Explosives - Smoke Streamer and Photoflash Bombs, and Ground Pyrotechnics (Part 1)

American Projectiles and Explosives

Aircraft Pyrotechnics

Smoke Streamer

T29

Overall length: 47.5 inches
Body length: 40.5 inches
Body diameter: 8 inches

Wall thickness: 0.06 inches

Tail length: 11.5 inches
Tail width: 10.75 inches

Filling: 8 Modified Smoke Grenades M18
Total weight: 100 pounds

Fuzing: The Fuze M143 consists of a fuze body support mounting four bouchon grenade-type fuzes and an arming washer, and is threaded to fit the fuze adapter of the tube train.  The arming washer is 2.5 inches in diameter and has four arms 0.75 inches wide and one inch long.  The arming wire holds the arming washer over the bouchon levers until it is withdrawn.

Construction: The bomb body consists of a sheet-steel case with a filling plug in the base.  The four tail vanes are welded to the truncated cone with box-type interior struts.  The complete body assembly consists of this Practice-Bomb Case M38A2, a train tube, a grenade train, a closing plug, and a fuze.  The train tube is a seamless steel tubing three inches in diameter and 40 inches long, with a fuze adapter brazed to the after end.  Eight modified Grenades M18 filled with fast-burning mixture are inserted into the tube to form the grenade train.  Each grenade is modified by cutting a center hole in its base, and the bouchon fuze is omitted. 
 
The top of each grenade is coated with a starter compound which acts as the igniter for the adjacent grenade.  Four strands of quick match are knotted and inserted in the center hole of the top grenade in such a manner as to leave the knot and loose ends at the top to receive the fuze flash.  The eight grenades are held apart by spring steel separators.  A threaded closing plug seals the tube and protects the grenade train from moisture.  This plus must be removed just prior to use.  the bomb is brought up to the weight of approximately 98 pounds by filling the balance of the internal space with sand.

Operation: When the arming wire is pulled, the bouchon springs throw off the arming washer and handles, allowing the bouchons to fire.  This action ignites the quick match in the center hole of the top grenade, which in turn is ignited, and the flash is simultaneously transmitted to all the grenades.


Remarks: The colored streamer smoke bomb is used as a visual signal to be dropped by the lead plane of a bomber formation when the target has been determined.  Smoke emission begins approximately one second after release from the plane and continues for approximately 7,000 to 10,000 feet.

Photoflash Bombs

M23A1

Overall length: 25.4 inches
Diameter: 4.25 inches
Weight: 10.6 pounds
Weight of flash powder: 7.75 pounds

Fixed delay: 15 seconds
Duration of flash: 0.2 seconds
Intensity of flash: 150,000,000 candlepower
Release altitude: 4,000 to 7,000 feet

Use: This bomb is used to provide light of high intensity and short duration for night photography from low altitudes.

Description: The bomb case is made of cardboard closed with metal ends, one of which is marked "Front" to insure proper loading in the rack.  This end contains the hang-wire assembly just before the Fuze Assembly M23A1.  The fuze assembly is made up of the friction wires attached to the hang wire, match composition, quick match, delay element, upper and lower rings, and base ignition charge immediately adjacent to the flashlight powder charge.  The hang wire is attached to the arming-wire retainer.


Operation: When the bomb is released, the hang wire remains attached to the arming-wire retainer.  As the bomb drops, the hang wire pulls the friction wires through the match composition of the fuze.  The hang wire also pulls out the hang-wire container, allowing both the hang wire container and the bomb to fall free.  The flame from the match composition ignites a piece of quick match, which in turn ignites a delay element.  After 15 seconds, the delay element ignites the base charge of the fuze, which sets off the flashlight powder charge.  The flash lasts a fifth of a second.

AN-M46

Overall length: 48.4 inches
Diameter: 8 inches
Weight: 51.9 pounds
Weight of flash powder: 25 pounds

Burning time: 0.2 seconds
Peak intensity: 500,000,000 candlepower

Fuzing: M111A2, AN-M146

Use: The Photoflash Bomb An-M46 was developed so that planes engaged in night photography reconnaissance need not be limited to low altitudes.

Description: In appearance it resembles a conventional light-case bomb.  Uses a Fuze M111A2 in the nose, but it is issued unfuzed.  It also has two suspension bands for rack and shackle suspension.

Operation: When the bomb is dropped, the arming wire is pulled, starting the mechanical time fuze.  When the time set on the fuze has elapsed, the flashlight powder is ignited by the fuze booster.

Remarks: Because of the brilliance of the flash, it is detrimental to the vision to watch the explosion of photoflash bombs.  Extreme care should be exercised in handling these bombs, because the charge is very sensitive to friction, shock, and temperature.  These bombs should not be jettisoned over friendly territory, as they may function on impact.

Ground Pyrotechnics

One-inch Salute Mk 1 Mod 0

Length: 1.75 inches
Diameter: 0.75 inches


Use: This salute is used by the Marine construction battalions and amphibious training commands to simulate battle sounds of loud report and bright flash.


Description: Essentially a commercial-type firecracker, this salute is a spirally-wound paper tube closed at both ends with paper cups.  It uses the regular firecracker filling and fuse.

Firecracker Mk 2 Mod 0

General: This firecracker is used as a practice charge for booby traps and firing devices.  It produces a loud report, bright flash, and smoke.  It is designed to reduce the hazard of flying particles attendant upon use of a standard potassium perchlorate firecracker.  It is classified as fireworks, since it contains no high explosive.  Although coated with a waterproofing material, it should be stored in a dry place.


Installation: The coupling base of any standard firing device is pushed through the wax-filled hole in the hollowed end of the firecracker and rotated clockwise until at least two threads of the coupling base are inside the hollowed end.






Signal Light Mk 2

Red
Burning time: 7
Candlepower: 300

White
Burning time: 6
Candlepower: 250

Green
Burning time: 5
Candlepower: 600


Use: Signal Light Mk 2 is used primarily as a distress signal.


Description: The cartridge, sometimes called the Very signal, is similar in appearance to a 10-gauge shotgun shell.  The star charge is a tightly-packed cylinder of pyrotechnic material reinforced with wire and wrapped with quick match.  The propelling charge is composed of about 25 grains of black powder separated from the star charge by a hard felt pad.


Identification of the three types

Red Star: Paper wrapping is red; closing wad is corrugated

White Star: Paper wrapping is white; closing wad has a small cone in the center.

Green Star: Paper wrapping is green; closing wad is smooth.


Operation: The Signal Pistol Mk 5 may be used, as well as the Hand Projector Mk 3 or Mk 4.

The primer ignites the propelling charge, expelling the star out of the projector and igniting the quick match, which ignites the star as it leaves the barrel and burns as it rises to a height of about 200 feet.






Projector Type M17 - M22 Series (Obsolete)

Length w/o tail: 6 inches
Diameter: 1.6 inches
Delay: 6 seconds
Height of trajectory: 600 feet


Description: The signal is assembled in a cylindrical case, and equipped with a finned tail assembly for stabilization purposes.  The primer is located int he head of the signal, and the propelling charge is contained in a small cavity under the head.  The end opposite the primer is closed by a press-fit cap to which the tail assembly is attached.  The signal has a solid tail stem and an X-shaped fin.  Embossed letters on the fin indicate the color and type of star(s).


Operation: The signal is inserted nose-first into Ground Projector M3 or M4.  The projector is struck smartly on the ground, causing the primer to strike the projector firing pin.  The primer ignites the propelling charge, which projects the signal tail-first for approximately 100 feet.  The signal then reverses itself and reaches an altitude of approximately 600 feet.

High-Bursting Range Signal M27

No picture available

The Range Signal M27 is similar to the projector-type signals, except that it has no tail assembly.  It is fired only from the Ground Signal Projector M1A1.  The signal explodes at the top of its rise, producing a flash and a puff of smoke.

Next Time:  Ground Pyrotechnics (Part 2)