Marc A. Williams
ABSTRACT: Professional fireworks displays, as well as those performed by volunteers, have for many years relied on equipment designs and techniques that were established before the turn of the century. The use of steel mortars, the hand firing of individual aerial shells and the use of wooden racks for chain firing of finale effects have until recently been the industry standard. These techniques and designs are adequate for the use intended, as long as the shells function normally, but if a color shell "detonates" or a salute explodes in a mortar, the results can be catastrophic. Since these designs and techniques first came about, the severity of the legal repercussions from accidents at displays has increased to the point where such an event, however unlikely, now represents an unacceptable legal risk to the display company. In this article, designs are presented for finale racks and single shot mortars (for use in "dense-pack" style rack systems) that were developed at Night Musick Inc., and which significantly reduce the risk of catastrophic equipment failure in the event of a shell malfunction.
Keywords: overpressure, shell detonation, dense pack, finale rack, matrix rack, chain fusing
Ref: JPyro, Issue 2, 1995, pp7-14
(J2_7)
© Journal of Pyrotechnics and CarnDu Ltd
