Category:JPyro – Articles

R. Guilbeault and E. Contestabile   Abstract: Recoil from fireworks articles often arises as a concern in accident investigations or when fireworks are launched from unconventional locations such as rooftops, or other light building elements such as overhangs, from decks of small bridges or those of barges. In this latter case, the Authority Having Jurisdiction …
Continue reading Evaluation Of Multi-shot Firework Articles Using Mortar Recoil Measurements

Yuzo Ooki, Dayu Ding, Morimasa Higaki, and Tadao Yoshida Abstract: Burning and shot experiments have been carried out to examine the burning time and the trajectory of burning firework stars. The burning time in flight was longer than the stationary burning time. The trajectory of a burning star in the air was modeled assuming the …
Continue reading Exterior Ballistics of Firework Stars

Morimasa Higaki, Dayu Ding, Yuzo Ooki, and Tadao Yoshida Abstract: Burning experiments were carried out for stars and lifting charge in the air and in a closed vessel. Three types of stars were used, that is, ordinary spherical, half-restricted spherical and hemispherical surface-restricted stars were used as models for flying burning. Partly restricted stars gave …
Continue reading Burning Characteristics of Firework Stars and Lifting Charge

Kazuomi Itoh, Dayu Ding and Tadao Yoshida Abstract: The spectroscopic measurement of sparklers, torches and senko hanabi (Japanese sparklers) was  carried out. The three dimensional spectra of sparklers and torches showed that the peak intensities of the spectra fluctuate with time. In the burning of sparklers, white, titanium, senko and iron sparklers showed mainly the …
Continue reading Spectroscopic Measurement of Burning Toy Fireworks

Yasuhiro Sashimura, Mamoru Horiuchi, Hideo Watanabe, Maiko Watanabe, Dayu Ding and Tadao Yoshida Abstract: A shot test was examined for evaluating the ignitability of cylindrical bare and primed stars. The primed stars were more easily ignited than the bare stars. The ignition limit lift charge was defined and used for evaluating the ignitability. Though the …
Continue reading Tests for Evaluating the Ignitability of Firework Stars and Compositions

Kenneth L. and Bonnie J. Kosanke ABSTRACT: A concussion mortar can be defined as a device used to produce a noise and jarring shock for dramatic effect at events such as stage productions. It consists of a thick-walled tube, closed at one end to form a combustion chamber (barrel). A type of pyrotechnic flash powder …
Continue reading Concussion Mortar Internal Pressure, Recoil and Overpressure as Functions of Powder Mass

Wesley D. Smith ABSTRACT:This is the first in a series of tutorials that introduce the concepts of chemistry to practicing pyrotechnists. It begins with the fundamental ideas of atoms and molecules. The reactions of these entities, together with their symbols, their nomenclature, their stoichiometry, and their energetics, are then described with pyrotechnic examples. Keywords: chemistry, …
Continue reading Introductory Chemistry for Pyrotechnists, Part 1: Atoms, Molecules, and Their Interactions

Stewart G. Myatt ABSTRACT: This paper reports results taken from a wider investigation of the effect of various parameters on the fragmentation behaviour of steel firework mortar tubes. During simulated misfire experimental information was obtained relating to the role of the weld in determining rupture behaviour in seamed steel mortar tubes. The results have helped …
Continue reading Observations on the Behaviour of Seamed Steel Mortar Tubes

 Roland K. Wharton ABSTRACT: This paper examines previously published information on the heights attained by spherical firework shells and proposes some empirical relationships that enable rough estimates to be made of the height attained from knowledge of either the mass or the diameter of the shell. Keywords: shell height, shell mass, lift charge mass, shell …
Continue reading Observations on the Heights Attained by Spherical Fireworks Shells