American Projectiles and Explosives - Aircraft Pyrotechnics Introduction

American Projectiles and Explosives

Aircraft Pyrotechnics

General


These chapters on pyrotechnics deal with items whose principal function is either signalling or illuminating.  For instance, signalling smokes are treated as pyrotechnics, but screening smokes are discussed elsewhere, under the ordnance items which carry them.

The effectiveness of pyrotechnics is dependent on three major factors: design, position, and the atmospheric conditions prevailing at the time of use.  Variations of design govern the candlepower of the flare or signal, the color produced by the charge, and the continuity of the burning candle.  The color and reflective characteristics of the objective often affect the visibility of pyrotechnics.  Open ground, such as an airfield, will reflect three to four times as much light as will woods or deep water.  Position, distance, relative position, background, or angle of observation also alter visibility, while the degree of light or darkness, fog, haze, or other atmospheric conditions have obvious effects.

Composition

Pyrotechnic compositions are complex chemical mixtures.  On burning, they produce illuminations ranging in intensity from the "dark fire" used as an element of blinker signals to the brilliant flash produced by the photoflash bombs.  Standard pyrotechnics, in general, consist of compounds to provide oxygen for burning, such as chlorates and nitrates; aluminum or magnesium for fuel; salts of barium, copper, or strontium for color; and agents such as asphalt and paraffin for binding and waterproofing.

Pyrotechnics usually function by means of an igniter train similar to an explosive train.  In general, ignition is initiated by a primer mixture and intensified by a "first-fire" composition which ignites the luminous candle.

Handling and Stowage

All pyrotechnics should be handled with care.  Rough handling may cause immediate functioning of the item, or it may damage the item so that it will not function properly at the desired time.  Much of the pyrotechnic material is more sensitive than other types of ammunition.

Pyrotechnics should be stowed in the boxes or watertight containers in which they are shipped, whenever possible.  They must not be stowed with other types of ammunition.

Pyrotechnics should never be stowed where the direct rays of the sun can strike them.  They should be protected against excessive and variable temperatures.  If possible, the stowage space should be kept at a temperature below 100 degrees Fahrenheit, and must be kept dry and ventilated.




Disposition

 When directed by the Bureau of Ordnance, pyrotechnics may be disposed of by dumping overboard or burning.  Dumping is preferred, and must be done ten miles off shore and in water at least 100 fathoms deep.  Certain items must always be dumped, while other items may be either dumped or burned.

Methods of projection

Aircraft pyrotechnics

1. Pyrotechnic Pistol AN-M8:  This pistol is used on aircraft with the Mount M1 and fires through an opening, in the fuselage.  It can also be detached from its mount and fired by hand.  It is generally used for signalling from aircraft in flight, to troops on the ground or to other aircraft.

2. Hand Projectors Mk 3 and Mk 4:  These projectors are fired by holding the barrel in one hand and pulling back on the firing pin handle with the other.  They are used to fire Very's Signal Light Mk 2.

3. Signal Pistol M5:  This is a single-action, single-loading pistol that fires the Very's Signal Light Mk 2.

4. Very Pistol M5:  This is a single-action, single-loading pistol that fires the Very's Signal Light Mk 2.  It is not procured by the Navy.

5. Pyrotechnic Discharger AN-M5:  This is a double-action, multi-barrel (6) discharger used on aircraft when installation of pistols is not practicable.  It is used for the same purpose as the Pyrotechnic Pistol AN-M8.  It is not procured by the Navy.

6. Hand Pyrotechnic Projector M9:  This is a single-action, single-loaded projector which is fired by striking the firing pin with the hand or by striking the firing pin on the ground.  It is used for projecting signals from the ground to aircraft in flight.  It is not procured by the Navy.

7. Pyrotechnic Discharger M10:  This is a metal cylinder with a mushroom firing mechanism and a hinged locking stem.  It is used to fire the Red Star Signal M73.

Ground pyrotechnics

1. Ground Signal Projector M1A1:  This is a single-loaded manually operated projector used to fire the High-Bursting-Range Ground Signal M27

2. Ground Signal Projector M3:  This is a single-loaded, manually operated projector that is fired by holding the projector in the hand and striking the base on the ground.  It is used to fire Signals M17 through M22.

3. Ground Signal Projector M4:  This projector is similar to the M3 and is replacing it.

4. Grenade Launchers M1, M2, M7, and M8:  This type of launcher is an extension to the barrel of a rifle or carbine.  It is used to fire ground signal M17A1 through M22A1, M51A1, and M52A1.

  

5. Tree Suspension Device T1, For Smoke Grenade:  This is a cardboard attachment containing about ten feet of suspension cord.  It is attached to a standard smoke grenade that is launched from a carbine or rifle.  The device is used to cause grenades to become entangled in trees or foliage, to permit emission of smoke above dense forests and foliage where it is readily visible to air observers.

Ship and submarine pyrotechnics

1. Signal Projector Mk 1 and Mk 1 Mod 1:  This is a barrel, about 30 inches in length which fits into a tube mounted on a three-legged stand.  The firing pin is part of a metal disc which acts as a valve.  It is used to fire Ship's Emergency Identification Signals Mks 1, 2, 3, and 4.

2. Submarine Rocket Pistol:  This is a single-loaded, breech-loaded pistol used to fire pistol rocket signals.

3. Submarine Emergency Identification Signal Ejector:  This ejector is similar to a miniature torpedo-tube arrangement.  It is used to fire Submarine Emergency Identification Signals, Submarine Float Signal Mk 1, Mk 1 Mod 1, or Mk 2 Mod 0, and False Target Shell, Mk 1.

4. Other Projectors:  These include Hand Projectors Mk 2 and Mk 4, and pyrotechnic Pistol An-M8, which are described above under Aircraft Pyrotechnics.  There is also a High-Altitude Mortar Mk 20 being developed, to which official nomenclature is being assigned.

Next Time: Aircraft Pyrotechnics - Pistol and Hand-Size (Part 1)