American Projectiles and Explosives - A.A. Flares and Target Identification Bombs

American Projectiles and Explosives

Aircraft Pyrotechnics

A.A. Target Flares

Mk 1 (Obsolete)

Length: 21.4 inches

Diameter: 3.8 inches

Weight: 12 pounds

Burning time: 3 minutes

Intensity: 280,000 candlepower

Use: The flare provides a target for both day and night practice firing of anti-aircraft guns.

Description: The flare consists of an illuminant tube and a cable-container tube made of rocket paper.  These are joined end-to-end under the external metal reinforcing band.  Both ends are closed by chip-board discs held in place with tape.  The cable ring is attached to the snubber cable at the end which protrudes through the cover disc of the flare assembly.  The snubber cable is attached to the base block with staples.

Friction wire is attached to the end of the snubber cable and extends through the primer composition, which is adjacent to the quick match which runs through a cardboard tube in the center of the illuminant.  At the end of the quick-match tube is a firecracker fuse terminating in the first fire composition, which is in contact with the main illuminant charge.

Streaming: The flare may be streamed from any plane from which an aircraft or anti-aircraft target reel can be mounted.

Operation: The flare slides back along the tow cable until the cable ring is stopped by the target release mechanism.  Force exerted on the snubber cable pulls off the end of the cable-container tube, and five solder snubbers are stripped off.  The staples holding the snubber block to the base block are withdrawn by the pull exerted.  Friction wire attached to the end of the snubber block is pulled through the primer.  The flame from the primer ignites the quick match, which in turn ignites the firecracker fuse igniting the first fire charge.  The first fire composition ignites the illuminant.

M50, M77, M78, and M79

No picture available

M50

Length: 22.8 inches

Diameter: 2.5 inches

Weight: 7.13 pounds

Color: White

Intensity: 50,000 candlepower

M77

Length: 23.5 inches

Diameter: 4.25 inches

Weight: 21.1 pounds

Color: Red

Intensity: 207,000 candlepower

M78

Color: Amber

Intensity: 80,600 candlepower

M79

Color: Green

Intensity: 108,500 candlepower

Use: Target Flare M50 has the same use as Target Flare Mk 1.  Target Flares M77, M78, and M79 are assembly markers from which succeeding elements of a forming squadron or group of aircraft can form a target under conditions of poor visibility and congested traffic patterns.

Description and Operation: These are the same as for Target Flare Mk 1.

Remarks: These flares are not under procurement by the Navy at present.

Mk 72 Mod 1

Length: 36 inches

Diameter: 8 and 3/4 inches

Filling: Smoke Composition

-68% Fire Orange dye

-15% Lactose

12% Potassium Chlorate

5% Asbestos shorts

Weight: 45 pounds

Fuzing: 4 pull-type igniters

Construction: This target identification bomb consists of two units, a sheet-steel bomb body casing and a parachute assembly packed in a molded container or pack which is attached to the bomb body by means of four bayonet joints.  The parachute pack houses a four-foot baseball-type parachute, the chute shroud lines, the load cables, the igniter cable, and a static cord which extends out of the top of the pack.  Bomb body casing contains a base block in the tail which incorporates the igniter assembly, 12 vent holes, and four eye bolts.  Load cables are attached to the eye bolts; igniter cable is attached to the pull-type igniters.  Between base block and the nose are the upper and lower candle assemblies.

Suspension: Horizontal suspension is provided by two lugs 14 inches apart, welded onto suspension bands which are bolted to the bomb case.

Operation: Upon release of the bomb, the static cord is retained by the rack or shackle to which it is attached.  The static cord, through a series of short lines inside the pack, removes the molded cover of the pack and pulls the parachute out.  After the parachute is out, the static cord separates from the parachute and is retained by the rack or shackle.  As parachute opens, the igniter cable jerks out the four pull igniters, which ignite the primers.  The primers ignite the firecracker fuze running through the upper candle, which in turn ignites the candle.  The candle burns from the inside toward the outside, evolving colored smoke that permeates holes in the candle case and escapes through vent holes in the bomb case.  The lower candle is ignited by the firecracker fuse about the time the upper candle burns out.

The total burning time is approximately five minutes, during which time the bomb produces a red-orange smoke in sufficient volume to be seen at 15,00 feet for 10 miles, under normal conditions.

Remarks: Target Identification Bomb Mk 72 Mod 1 is used by air-coordinator planes or by scout planes from battleships to pin-point shore targets.  This colored smoke marker is for use over land only, as the bomb does not float.

Greatest accuracy can be obtained by releasing the bomb from altitude of 500 to 1,000 feet.

This bomb can be carried on all external double-suspension racks and shackles.  In addition to the use of this bomb on double-suspension racks or shackles, it can be suspended from the Bomb Adapter Mk 5 Mod 0 (used with Launchers Mk 5 and Mods) when that item is available.  These bombs have been successfully released from external suspension on all types of planes in any flight attitude.  They can successfully withstand catapult launching and arrested landings.

M75A1 and M84A1

  
Overall length: 53.1 inches
Body length: 39 inches
Body diameter: 8.2 inches
Wall thickness: 0.06 inches
Tail length: 12.9 inches
Tail width: 10.9 inches

Filling: Red iron oxide (hematite)
Weight of filling: 72 pounds
Total weight: 102 pounds

Fuzing:
-M75A1 --- M108
-M84A1 --- AN-M147


Construction: Target Identification Bombs M84A1 and M75A1 are identical with the exception of the fuse, and the two bombs are similar in construction to the Chemical Bomb AN-M47A2.  The body is of sheet metal with box-type tail fins welded to the conical section.  The Burster M4 runs through the entire length of the bomb and is closed at the forward end by a closing plug.  A filling plug is placed in the fin cone of the bomb body, to facilitate loading the hematite charge (red iron oxide).  The fuze fits into the forward end of the burster.


Remarks: The Target Identification Bomb M84A1 is intended for release by the lead or "pathfinder" plane to indicate the bomb-release line for bombers in formation when operations are carried out above an overcast and ground targets are not visible.  The bomb was designed to produce a red smoke cloud which would remain at the bursting point for a period of ten minutes under normal air conditions and would be visible for a distance of 15 miles at an altitude of 25,000 feet.

The M75A1 is used for target identification in practice, to mark targets on snow-covered bombing ranges.


 

M89, M90, M91, M98 and M100

  
Overall length: 51.8 inches
Body length: 35.8 inches
Body diameter: 10.8 inches
Wall thickness: 0.27 inches
Tail length: 15.7 inches
Tail width: 14.9 inches

Type of filling: 61 pyrotechnic candles (red, green, or yellow)
Weight of filling: 95 pounds
Total weight: 240-265 pounds

Fuzing: AN-M146, M144


Use: The flares are used in emergency night landings.


Construction: The body is a modified 250-pound G.P. Bomb AN-M57 body with a metal closing cup riveted to the base.  An integral booster of four ounces of black powder is placed immediately behind the fuze-seat liner and serves as an expelling charge.  A wooden nose piece fits around this booster, and a steel piston, in turn, is seated in the base of the nose piece.  A steel tube or piston stem is welded through a hole in the piston and extends from the black-powder booster tot he plywood ignition disc in the center of the bomb.  Six wooden thrust members reach from the piston plate to the tail closing cup and serve to transmit stress to this cup without imposing any of the force on the candles.  Felt 1/8 inch in thickness lines the entire interior cylindrical surface of the bomb.  The 61 candles are in two banks of 30 and 31, and have their ignition ends facing toward the quick-match strands stapled on the ignition disc which separates the two banks.


Tail Construction: The tail, in appearance, is a standard box-type tail.  It is attached to the bomb by means of four spring latches fitting into cut-outs in the tail closing cup and can be locked in place by stamped steel strips pivoting over the ends of the springs.


Suspension: Horizontal suspension is provided by standard lugs, 14 inches apart.


Operation: When the aerial-burst fuze functions, the fuze booster ignites the black-powder booster or expelling charge in the bomb.  The force of the expanding gases from the booster, acting through the piston and thrust members, throws off the fin assembly and expels the candles.

Simultaneously, flash from the booster passes through the piston stem to the plywood ignition disc and the quick match, igniting the candles.

Remarks: The bombs are used to form a pattern of red, green, or yellow colored light approximately 100 yards in diameter around or on a target; the light should be visible from altitudes of 25,000 to 35,000 feet day or night.  They are used to spot individual targets, once the general target area has been marked by flares dropped by pathfinder planes.  The explosive charge in the candles M105 is ignited by the flare composition at the end of burning.  These charges serve to prevent any removal of the candles by the enemy, once the candles are on the ground.

The M89 contains 61 Non-Delay Candles M103.

The M90 contains 57 Non-Delay Candles M103 also; two Exploding Candles M105, burning for one minute, and two exploding candles burning for two minutes.

M91 has 16 Non-Delay Candles M103, 15 red 2.75-minute Delay Candles M104, 15 4-minute Delay Candles M104, and 15 5.25-minute Delay Candles M104.

The M98 contains 31 Non-Delay Candles M103, 10 Exploding Candles M105, burning for one minute, 10 Exploding Candles M105, burning for 1.5 minutes, and 10 Exploding Candles M105, burning for two minutes.

The M100 contains Two-Color Combination Candles M104.

Next Time: Smoke Streamer and Photoflash Bombs, and Ground Pyrotechnics (Part 1)

American Projectiles and Explosives - Depth Charges and Slick Markers

American Projectiles and Explosives

Aircraft Pyrotechnics




Day Depth Charge Marker Mk 1 Mods 1 and 2

Length: 11.88 inches
Diameter: 3.46 inches
Weight: 3.5 pounds
Weight of dye: 2.75 pounds
Weight of bursting charge: 30 grams
Effective releasing altitude: Up to 1,000 feet
Visibility: 3,000 yards from deck of ship; 5 miles from aircraft


Use: The marker is used to indicate the initial point of contact with submarines and provide a reference point for further search and attack during day operation.


Description: The marker consists of a circular wooden block on which is mounted a grenade-firing mechanism with a 15-second delay.  Fluorescein dye is contained in two cylindrical paper cans, one attached to each flat side of the wooden block; and a celluloid tube containing the black-powder bursting charge is attached to the delay element and extends through the wooden block into the paper cans.  The dye is rusty red in color when dry, but a water solution of the dye is yellow-green.


Operation: The operator clasps the marker firmly in one hand, being sure that the release lever is held against the body of the marker.  With the other hand, he pulls the safety ring which is attached to the safety cotter pin and launches the marker by throwing it over the side.  When the marker is released, the spring-loaded striker forces the release lever off.  The striker, rotating about a hinge pin, hits the primer that ignites the 15-second delay fuze.  The delay gives the marker sufficient time to reach the water and float on the surface, and then ignites the bursting charge.  The gases evolved from the charge burst the dye containers and spread the dye on the water, forming a yellow-green slick about 40 feet in diameter.  The slick lasts for 45 to 60 minutes.








Night Depth Charge Marker Mk 2

Length: 7 inches
Diameter: 5 inches
Weight: 2.5 pounds
Effective releasing altitude: Up to 3,000 feet
Visibility: 4 miles from deck of ship; 10 miles from aircraft

Burning time: 55 minutes
Ignition time (after impact): 70-90 seconds


Use: The marker is employed to indicate the initial point of contact with submarines and provide a reference point for further search and attack during night operations.


Description: The marker is a sealed, cylindrical, metal container that has a centrally located tube, sealed on both ends by tear strips with a pull ring attached, and containing calcium phosphide.  The main charge is calcium carbide that surrounds the central tube and is held in one end by a screen.  This produces a concentration of weight at one end and allows the marker to float in an upright position.


Operation: After the two tear strips are pulled off, the marker is launched by throwing it overboard.  Water enters through the small calcium carbide (producing an inflammable gas, acetylene) and with the calcium phosphide (producing a spontaneously ignited gas, phosphine).  Both gases escape from the small holes in the top and ignite within 70 to 90 seconds after impact with the water.  In extremely cold weather, the ignition delay may be somewhat longer.  The resulting flame is about nine inches high.  If it should be put out by rough water, the gases will ignite again.










Slick Marker Cartridge AN-Mk 1

No picture availabe

Length: 3.8 inches
Diameter: 1.5 inches
Muzzle velocity: 300 feet/sec
Weight of dye: 28 grams


Use: This marker is used primarily to provide reference points for aircraft engaged in anti-submarine warfare.


Description: The cartridge is composed of a shotgun-type case containing a primer, a black-powder propelling charge, and the projectile.  The projectile has a thin aluminum case and contains 28 grams of fluorescein dye and a black-powder bursting charge initiated by a Bickford-type fuze.


Launching: The marker cartridge is fired in the Pyrotechnic Pistol AN-M8, which may be held in the hand or mounted in the Mount M1.

Operation: When the cartridge is fired, the black powder in the head of the case propels the projectile from the pistol and at the same time ignites the Bickford fuze.  The fuze burns for about eleven seconds before igniting the bursting charge which expels the fluorescein dye out into the water.  The projectile has a positive buoyancy and will remain near or at the surface until a small, bright green slick is created.


Remarks: This cartridge should not be fired from altitudes greater than 500 feet, because the cartridge must be in the water when it bursts.

Slick Marker AN-M59

No picture available

Length: 10.875 inches
Diameter: 3.375 inches
Weight: 2.9 pounds


Use: This is the standard all-purpose sea marker for daylight use: to provide reference points; to aid in determining drift; and to provide practice bombing targets on water.


Description: This marker consists of a paper composition case filled with a  fluorescein dye.  It is protected by a cylinder of papier-maché, which does not interfere with its function.


Launching: The marker is dropped by hand from a plane.


Operation: Upon impact with water, the case shatters and the dye spreads upon the surface.







Army Flares

M8 and M8A1

No picture available
  
Length: 25.5 inches
Diameter: 4.25 inches
Weight: 18 pounds
Color: Yellow
Intensity: 850,000 candlepower
Burning time: 3 minutes
Rate of fall after ignition: 500 feet/min


Use: The flares are used in emergency night landings.


Description: Each flare consists of a cylinder containing an unshaded candle.


Operation: Army Flares M8 and M8A1 are similar in operation to the Flares An-M26, except that the hang wire pulls the parachute directly from the case.


Remarks: The M8 is similar to the M8A1, except that the latter flare burns with a white light approximately 250,000 candlepower.

M9 and M9A1

Picture seen above

 M9 
Length: 13.8 inches
Diameter: 2 inches
Weight: 1.9 pounds
Color: Yellow
Intensity: 60,000 candlepower
Burning time: 1 minute
Rate of fall after ignition: 400 feet/min


M9A1
Length: 15.05 inches
Weight: 2.1 pounds


Use: This flare was designed to satisfy the requirements for a small parachute flare for reconnaissance.


Description: The flare consists of a cylinder containing a candle, designed to be projected with the Pyrotechnic Pistol AN-M8.


Operation: The flare is discharged from the pistol and the delay fuse is ignited.  The fuse burns for 2.5 seconds and ignites the expelling charge, which expels the candle and parachute, simultaneously igniting the candle.


Remarks: This flare is not procured by the Navy.

M24 (Obsolete)

Picture seen above

Length: 37 inches
Diameter: 8 inches
Weight: 47 pounds
Color: Yellow
Intensity: 800,000 candlepower
Burning time: 3 minutes
Releasing altitude: 2,500 to 3,000 feet
Speed of release: Not over 200 mph
Rate of fall after ignition: 700 feet/min


Use: The flare is a substitute standard for night observation and bombardment.


Description: It consists of a simple cylinder without hemispherical nose or tail fins; otherwise, it is similar throughout to the AN-M26, without the nose time fuze.


Operation: The flare is similar to the AN-M26 except that the hang wire acts directly to pull the parachute from the flare case.


Remarks: This flare was not procured by the Navy.

M6 and AN-M26

Picture seen above

Length: 50 inches
Diameter: 8 inches
Weight: 53 pounds
Color: White light
Intensity: 800,000 candlepower
Burning time: 3 to 3.5 minutes
Releasing altitude: 4,000 to 25,000 feet
Rate of fall after ignition: 700 feet/min


Use: These flares are used to provide illumination for night bombardment; also may be used to blind anti-aircraft defenses.


Description: The flare is enclosed in a metal cylindrical case with a rounded nose and tail fins.  In the nose is a mechanical time fuze.  The tail end is closed with a shipping cover that has a handle attached and sealed by a strip of tape.  The case is equipped with two suspension lugs 14 inches apart.


Operation: When the flare is dropped, the arming wire is pulled, allowing the vanes of the nose fuze to rotate.  The hang wire is retained and pulls off the cover of the stabilizing-sleeve compartment.  As the flare continues to drop, the tear wire and tear-wire cord pull out the stabilizing sleeve, and the cover-lock cord attached to the shrouds of the stabilizing sleeve unlocks and pulls out the cover lock.  When the sleeve is fully extended, the tear wire breaks, allowing the flare to fall free, stabilized in flight by its fins and stabilizing sleeve.

When the nose fuze functions, the gases of the black-powder booster force the releasing-cup cover out of the detachable cover, releasing the retaining pins from the groove in the flare case and freeing the detachable cover.  As the detachable cover is pulled out by the stabilizing sleeve, a pull-out cord pulls out the parachute.  when the parachute opens, the flare stops with a  jerk, breaking the pull-out cord (which allows the stabilizing sleeve assembly to fall free) and pulling the entire flare assembly out of the flare case (which then falls away).  The sudden stop also pulls the friction wires through the igniters, starting the six-second delay through the center of the candle, which allows full opening of the parachute.

The shock caused by the opening of the parachute is taken by the shock absorbers, made of copper tubing in a spiral or coiled shape.  they straighten out in absorbing the shock.  After the parachute is opened, the delay ignites the first fire, which ignites the candle.  When the first fire is ignited, the gases formed by burning force the rib retainer down, and the spring-loaded ribs jump out, opening the glass-cloth shade.


Remarks: The Flare AN-M26 can be dropped at air speeds up to 240 knots, but above that the stabilizing sleeve is apt to tear away.  The Flare M26 cannot be dropped at air speeds greater than 130 knots, for the same reason.

Next Time: A.A. Flares and Target Identification Bombs

American Projectiles and Explosives - Drift Signals and Navy Flares (Part 2)

American Projectiles and Explosives

Aircraft Pyrotechnics




Mk 5 and Mods

Length: 27 inches
Diameter: 4.75 inches
Weight: 18 pounds
Burning time: 3 minutes
Intensity: 750,000 candlepower
Release altitude: 3,500 - 15,000 feet
Rate of fall after ignition: 450 feet/min

Color:
-Mk 5 and Mk 5 Mods 1 and 2: White
-Mk 5 Mods 3 - 7: Yellow


Use: The Navy Flare Mk 5 illuminates an area for reconnoitering, bombing, or landing.


Description: The complete flare consists of a parachute, an illuminant, and an impregnated chip-board case.  It is closed on the parachute end by several layers of chip-board discs held in place by gummed cloth tape and sealed with paraffin, and on the fuze end, which contains the Ensign Bickford fuse, by a metal cover.  There are two metal steadying bands fastened around the case, against which the steadying forks of the bomb rack rest.  The complete flare in its case is issued in a waterproof metal container.


Operation: The setting of the Ensign Bickford time delay fuse is made by turning the lock screw on the metal firing mechanism housing to the desired delay, which is indicated on the bevel of the fuze-setting ring.  The numbers indicate the vertical distance the fuze will drop before igniting.  When the correct setting is obtained, the firing mechanism is secured by screwing the lock screw until its point is buried in the flare case.

When the flare is released from the plane, the arming plate is retained on the plane, the rip cord is torn from the side of the flare case, and the cover on the fuse end is flipped off.  The rip cord is attached tot he snap cord that passes around a lug on the firing lever and is secured to the fuse block.  As the flare continues to fall, the snap cord is pulled, overcoming the lever spring and cocking the firing lever.  When a tension of approximately 38 pounds is reached in the snap cord, it breaks, releasing the firing lever and the lever spring, then driving the firing lever back against the fulminate of mercury primer.  The flare now falls free.

The primer ignites the black-powder pellets in the fuze plunger.  the expanding gases from the burning black powder propel the sharp point of the plunger radially outward into the Ensign Bickford fuse that causes its ignition.  The time fuse burns its predetermined length at the rate of approximately 12 inches per 60 seconds, and ignites the quick match under the firing block.

The flash produced by the quick match ignites the firecracker fuse stapled to the ignition composition.  The gases evolved when the ignition composition begins to burn force the end discs out at the parachute end, then expel the parachute and illuminant.  The parachute tube, which is of split construction, falls away; the parachute opens; and the retention cable slides through the trigger snap on the end of the shroud lines until it reaches the cable stop.  A short length of cable on one side of the cable stops suspends the flare case, and a longer length on the other side suspends the illuminant.  This keeps the case from dropping as a missile hazard.  The sudden shock caused by the contact of the cable stop with the trigger snap is taken up by a shock absorber.  This is done by pulling a cable containing lead balls, called snubbers, through a hole which is of smaller diameter than the diameter of the snubbers.  As each snubber passes through the hole, part of it is sheared off, thus absorbing part of the shock.,  The last ball is of much greater diameter and acts as a stop.


Remarks: In later models a new type of shock absorber eliminates the use of lead snubbers.  The cable pulls through a connection in which friction absorbs the shock of the parachute opening.









Mk 6 and Mods and AN-Mk 6 Mod 5

Length: 37.75 inches
Diameter: 5.4 inches
Weight: 30 pounds
Burning time: 3 - 3.5 minutes
Intensity: 1,000,000 candlepower
Release altitude: 3,500 - 15,000 feet
Rate of fall after ignition: 450 feet/min
Color: Yellow


Use: These flares are used to illuminate a large area for reconnoitering and bombing, and also as a blinding effect on the operators of anti-aircraft weapons.


Description: The complete flare consists of the illuminant, a parachute, and an auxiliary parachute contained in a shellac-impregnated chip-board case.  The case is closed on the parachute end by several layers of chip-board discs held in place by gummed cloth tape and sealed with paraffin, and on the illuminant end by an Ensign Bickford time fuse and a metal cover.  To the snap cord of the Ensign Bickford fuse is attached the rip cord, which is taped down along the side of the flare case.  There are two metal steadying bands around the case, against which the steadying forks or sway braces of the bomb racks rest.  The flare is issued in a waterproof metal container, and should be kept there at all times when not installed in an aircraft.


Operation: When the flare is released, the arming plate is retained by the plane and the rip cord is torn from the side of the case, flipping the metal cover off the Ensign Bickford fuse.  The operation of the fuse is the same as given in the Navy Flare Mk 5.

The gases evolved when the ignition composition begin to burn, force the end out of the flare case.  Net, they expel the auxiliary parachute, the parachute in its case, and the illuminant.  The flare case falls clear.  The auxiliary parachute opens and retards the parachute in its case, to which it is attached, and the illuminant pulls the parachute out of its case.  The auxiliary parachute and parachute case fall away, and the parachute opens.


Remarks: This flare also incorporates a shock absorber as used in the Navy Flare Mk 5, with either lead balls passing through a hole of smaller diameter than the lead balls, or a special connection utilizing friction to absorb shock of the parachute opening.

The Flare AN-Mk 6 Mod 5 differs from the Mk 6 and Mods in that the arming wire has swivel loops instead of an arming plate.








Flare Container Mk 1 Mod 0

Use: The Flare Container Mk 1 Mod 0 is an electrically operated jettisonable container for carrying six aircraft parachute flares of the Mark 6 type only, which may be released one at a time by electrical impulses from a 24-volt battery.  The container may be suspended from any standard single or double-hook bomb rack.


Construction: It is necessary to cock the mechanism manually before the container can be loaded or unloaded.  The container holds six flares, three on each side of the vertical panel, one above the other.  The dividing panel assembly supports the flares by metal arms or chocks.  The flares are loaded with the fuze end aft, and the end of the lanyard is secured to the container.  The energy for the operation of the container is stored in torsional springs and released by a solenoid.  By wiring in series, several containers can be operated to secure an uninterrupted release of a series of more than six flares.


Operation: When the solenoid is energized, the spring-loaded plunger, which is linked mechanically to the release rack, retracts completely, thereby effecting the release of one flare.  The solenoid plunger will remain retracted so long as the current I son.  To release another flare, the circuit must be broken long enough to allow the spring-loaded plunger to return to the normal position before applying the next impulse.  The maximum rate of release is about 10 flares per second, which is the highest rate practicable in order to prevent interference between individual flares.

The cocking lever should always be in the "safety" position when on the ground, and only switched over to the "operational" position before the plane takes off.  Correctly loaded flares are a fire hazard, since they are always armed.


Remarks: When the container is used in a bomb bay, it is intended that it be used without the nose and tail fairings.  If desirable, the spring doors may also be removed.

AN-Mk 8 and Mods

Length: 25 inches
Diameter: 4.75 inches
Weight: 16 pounds
Burning time: 3 to 3.5 minutes
Color: Yellow (Pale)
Intensity: 600,000 candlepower
Minimum release altitude: 2,500 feet
Rate of fall after ignition: 500 feet/min


Use: This flare was developed specifically for night anti-submarine warfare.


Description: This flare is the same as the Navy Flare Mk 4, except that the overall length is two inches shorter and the illuminant in the Mo 0 and Mod 1 has a 90-second delay fuse through its center or a 120-second delay fuse in the Mod 2.


Operation: This flare is similar to the Navy Flare Mk 4, except that, when the ignition wire attached to the suspension cable is pulled, it pulls the friction wires in the Ensign Bickford fuse igniter, igniting the delay fuse running through the center of the illuminant.  When the parachute opens, the illuminant is pulled out of the flare case, and the flare case falls away.  The sudden shock caused by the opening of the parachute is taken up by a shock absorber of the solder balls and aperture type employed on the Flare Mk 4.  Full suspension of the flare occurs approximately 30 to 50 feet below the plane, and 90 or 120 seconds later the first fire of the illuminant is ignited by the delay.


Remarks: The Flare Mk 8 Mod 1 and Mod 2 can be launched at speeds up to 220 knots, but the Flare Mk 8, which does not have the snubbers for the shock-absorber effect, should not be launched at speeds greater than 150 knots.

Mk 10 Mod 0

No picture available
  
Length: 37.75 inches
Diameter: 5.4 inches
Weight: 30 pounds
Burning time: 4.5 minutes
Color: Yellow (Pale)
Intensity: 750,000 candlepower
Release altitude: 3,500 - 15,000 feet
Rate of fall after ignition: 450 feet/min


Use: This flare is employed to illuminate an area for reconnoitering, bombing, or landing.


Description: The Navy Flare Mk 10 Mod 0 has the same dimensions as the Mk 6 and Mods.  The internal construction is similar to the Mk 5 and Mods, except that the Mk 10 Mod 0 has a metal suspension cup to which the suspension cable and pyrotechnic candle are fastened, and the Mk 5 and Mods has a wooden suspension-base block.


Operation: The operation is similar to that of the Navy Flare Mk 5 and Mods.


Remarks: Though this flare has a specified light intensity of 750,000 candlepower, tests have shown that it has a light intensity of 800,000 to 850,000 candlepower.  In the future it may be manufactured so as to have a light intensity of approximately 1,000,000 candlepower.

Mk 11 Mod 0

  
Length: 37.75 inches
Diameter: 5.37 inches
Weight: 30 pounds
Burning time: 3 minutes
Color: Yellow (Pale)
Intensity: 1,000,000 candlepower
Minimum release altitude: 2,500 - 4,000 feet
Delay: 90 to 180 seconds


Use: The Navy Flare Mk 11 will supplement the AN-Mk 8 for night anti-submarine warfare.


Description: The shellac-impregnated chip-board case of this flare has two metal steadying bands fastened to it and is closed at the parachute end by a chip-board disc held in place by a gummed cloth and sealed with paraffin.  The rip cord is wound around a spool at the parachute end of the flare, and is attached to the parachute tube through a release key.  The parachute and parachute shrouds are enclosed in the parachute tube.  The shrouds are attached to a suspension cable, which is attached to the illuminant assembly.

The fuze end of the flare is closed by a metal fuze and a cover which must be removed when setting the fuze.  Immediately below the cover is a firing lanyard with a swivel loop on one end and a clip-type loop on the other.

The selective-delay ignition device is similar to the fuze used in the Mark 5 and Mark 6 types of aircraft parachute flares, the chief difference being that the fuze is initiated by a pull cord running through the center of the illuminant instead of by a firing lanyard.  The pull cord is attached tot he suspension cable.  A safety screw keeps the firing lever of the fuze in position during shipping.  A friction-type snubber is employed at the lower end of the suspension cable.


Operation: The metal fuze-end cover is removed and the firing lanyard withdrawn.  The clip-type loop or the metal lanyard is attached to the arming wire retainer of the launching gear.  A selective delay setting is made by pulling up on the index pin, turning the indicator to the required delay, and then releasing the index pin.  The safety screw is removed.

As the flare falls away from the aircraft, the swivel loop of the firing lanyard is held by the arming-wire retainer.  The rip cord, which is fastened to the metal lanyard through the clip-type loop, unwinds from the wooden spool inside the end of the flare casing, thus tearing away the end of the flare casing.  The rip cord then pulls out the spool and the parachute tube containing the parachute.  the spool falls away.  Since the parachute tube is held by the rip cord, the pyrotechnic candle and flare case fall away.  The weight of the candle pulling on the suspension cable and parachute shrouds draws the parachute out of the tube.  When the parachute and shroud lines are fully extended, the release-key cord becomes taut and pulls one end of the release key down.  This allows the rip cord to pull through the key and become detached from the parachute and the tube, which falls clear.  the rip cord and metal lanyard are retained by the aircraft.  The parachute opens and suspends the flare 30 to 50 feet below the aircraft.  The parachute pulls the candle out of the flare case, which falls free.

The selective-delay ignition device functions in a manner similar to the fuze used in the Flares Mk5 and Mk 6.  The fuze is initiated by a wire pull cord which passes through a hole through the center of the candle.  The pull cord is attached to the suspension cable in such a manner that it is pulled away from the primer and then releasing, striking the primer and igniting the powder pellets in the fuze plunger.  The burning powder forces the pointed end of the plunger into the Bickford Fuse which is ignited by flame through holes in the plunger.  The time fuse ignites the quick match under the fuze block, which in turn ignites the quick match and firecracker fuse stapled to the ignition composition.  the ignition composition ignites the candle.  The gases generated by the burning candle blow the fuze assembly off from the end of the pyrotechnic candle, and the fuze falls clear.


Remarks: This flare differs from the AN-Mk 8 and Mods in that there is a selective delay between the opening of the parachute and ignition of the pyrotechnic candle.  The selective delay allows a single patrol plane to drop a flare near the target and then get into position for the attack before the flare discloses his position.

Float Flare Mk 17 Mod 0 and Mod 1

Length: 60.75 inches
Diameter: 9.5 inches
Weight: 88 pounds
Color: Yellowish white
Intensity: 1,000,000 candlepower
Burning time: 4.5 to 5 minutes

Delay:
-Mod 0: 1 minute
-Mod 1: 5.5 minutes


Use: This flare is used to illuminate enemy surface craft.


Description: The flare case is a cylindrical body of sheet metal tapered at one end from 9 and 1/2 half inches to approximately 4 inches, which section has a lead weight and four membrane-covered ports approximately two inches in diameter.  The after end of the flare case is closed by a canvas bag containing a parachute.  The candle is in a central tube so mounted as to keep the burning mixture at the top of the flare by spring action.


Operation: When the flare is removed from the box, the adhesive tape on the cover is pulled off and membranes covering the ports in the nose are punctured.  The flare is loaded into the bomb rack with the pointed end of the flare toward the forward end of the plane.  Sufficient static line is pulled from the pocket in the parachute canvas bag to allow the ring attached to the end of the line to be secured to the arming-wire retainer on the rack or shackle.  On launching, a combination-type fuze causes a delay before the pyrotechnic candle burns.


Remarks: Flares having a one-minute delay setting may be released at elevations between 100 and 4,000 feet; 5 and 1/2-minute delays may be released from greater altitudes.  Descent is at a rate of between 80 and 100 feet per minute.

A continuous illumination of nine minutes duration may be obtained by dropping a Mod 0 and a Mod 1 together.

Next Time: Depth Charges and Slick Markers