Special effects, pyrotechnic

Theatrical Pyrotechnics or Special Effects. Many spectacular visual and audible effects are produced for stage presentations of both music and drama, and many motion pictures and television shows incorporate pyrotechnic and explosive special effects to Hven up the presentation. These spectacular effects are a combination of pyrotechnics, explosives, combustion, and electronics. After the effects are filmed or videotaped, they are often enhanced by slow-motion replay and by the addition of more exciting noise. A real explosion is over in milliseconds, and hence there is a need for electronic enhancement to create a more spectacular effect on the screen. 

The production of brilliant sparks is one of the principal effects available to the fireworks manufacturer and to the "special effects" industry. Sparks occur during the burning of many pyrotechnic compositions, and they may or may not be a desired feature. 

Pyrotechnics may be considered as mixtures of materials capable of combustion when suitably initiated to produce a special effect. In most cases, pyrotechnic compositions consist of a fuel and an oxidizer together with a binder to give structural integrity and additives for imparting special effects. 

Pyrotechnics are specially formulated to produce a large volume of gases and a lot of energy. The special effects due to pyrotechnics are classified as... 

Pyrotechnics are employed to produce special effects other than those produced by high explosives and propellants. There are several special effects produced by pyrotechnics which are classified according to their nature. A brief on their nomenclature, special effects and applications is given in Table 5.1. 

Table 5.1 Pyrotechnics special effects, nomenclature/devices and applications.

Pyrotechnics are invariably intimate mixtures of finely powdered fuels and oxidizers together with other additives in order to impart special effects depending on the requirement. Pyrotechnic formulations burn very rapidly when ignited as a loose powder. However, there are some applications where controlled steady burning is required for a definite time and this is achieved by compressing the mixture into columns surrounded by a relatively non-combustible material so that combustion proceeds from one end to other, layer by layer for a long duration. 

Pyrotechnic formulations in general consist of physically intimate mixtures of various combinations of fuels and oxidizers, of which many are in use. The tailoring of the formulation is done by changing the proportions of fuel, oxidizer and other ingredients and also by changing their particle sizes. In addition, additives are used in order to impart special effects to the formulations. 

To these items must be added the devices used in the motion picture industry for special effects. Most of these are clever mechanical arrangements but pyrotechnics plays a part, especially in battle scenes. A recent (1966) book is devoted to this subject." " A noteworthy fact is that a manufacturer of such items advertises, among others, red, green, and yellow flash powders." ... 

TITANIUM SPARKS (See color insert following page 112) A titanium fountain uses relatively coarse titanium particles blended into a moderately fast-burning pyrotechnic composition to produce a beautiful spray of white sparks. This type of fountain effect is widely used in the fireworks industry as well as in theatrical pyrotechnical articles (special effects) for stage presentations. (Photo by Tim Wade and Dennis King, courtesy of MP Associates.)... 

Small arms ammo can be so severely affected by moisture that a special indicating lacquer was developed for 20mm rounds which changes color from grey to black on w exposure (Ref 59) Effect of Moisture on Pyrotechnics Pyrot formulations usually contain finely powdered metal fuels such as Mg, Al, Fe, Cu, etc, all of which can react with moisture to yield H2. This effect has been dubbed gassing in pyrot circles, and is the major problem associated with the storage of hermetically sealed ammo of this... 

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