Archive for March 2007

Measurement of Aerial Shell Velocity

K.L. and B.J. Kosanke

Introduction: In addition to satisfying general curiosity, there are technical questions requiring knowledge of aerial shell velocity. For example, a calculation of how far down range aerial shells will have traveled at various times after having been fired from highly angled mortars requires knowledge of the shell’s muzzle velocity and its effective drag coefficient. In particular, the authors (along with Mark Williams) plan to determine the maximum horizontal range of aerial shells which burst after the normal time fuse delay. This study could be conducted empirically by firing different size shells from mortars at various angles. However, such an approach could be prohibitively expensive and time consuming, and it probably would not allow the examination of as many cases as desired. As an alternative, the question could be examined using a computer model of aerial shell ballistics.[1] This would be relatively inexpensive and any combination of shell velocity, shape, and mass; time fuse delay; and mortar angle could be considered. However, without verification using results from actual testing, the modeled results would always be at least a little suspect. Accordingly, the best choice is to conduct a number of field tests to verify the correct performance of the computer model, and then to model the cases of interest. This article is the first in a series, which will describe the down range study introduced above.


Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 3, (1993-1994), pp 56-61
(K3_56)
Download/Purchase Options :

You must be logged in to purchase or download articles.

The Role of the Expert Witness

K.L. Kosanke

There is a good deal of misunderstanding as to the role of the expert witness in our legal system. Because of this; because I think the subject is intrinsically interesting; and because no one else has chosen to present the subject in an article for the fireworks trade, I have decided to make an attempt at an explanation. However, it should be understood that I have not made a study of law or of our legal system. Accordingly, while I believe I am correct, I can only give my understanding and belief as to the proper role of the technical expert witness.


Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 3, (1993-1994), pp 53-55
(K3_53)
Download/Purchase Options :

You must be logged in to purchase or download articles.

Electric Ignition of Shock Tube Firing Systems

K.L. Kosanke

NOMATCH™ is a new system for igniting fireworks that replaces quick match with shock tube plus flame-to-shock (or electric-to-shock) and shock-to-flame attachments. The system was introduced by B & C Products, Inc., with a press release included in the July 1994 Issue of American Fireworks News, an article in the July 1994 issue of Fireworks Business, and a demonstration and seminar at the 1994 Pyrotechnics Guild International (PGI) convention.[1] There was considerable discussion, among the PGI convention attendees, of the potential usefulness of this new system in various fireworks environments. The safety and performance advantages of the system seem obvious.[1] Below is a brief discussion of two low cost alternatives for electric ignition of shock tubing. For the most part, these are well known and commonly used methods; however, probably not among those in the fireworks trade. It is hoped that this information is interesting and possibly will aid in the introduction of this system.


Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 3, (1993-1994), pp 51-52
(K3_52)
Download/Purchase Options :

You must be logged in to purchase or download articles.

“Skip Burning” of Visco Fuse

K.L. and B.J. Kosanke

In late December 1978 more than 100 serious injuries were reported in eastern Kentucky, apparently the result of defective visco fuse.[1] The defective fuse had been used by a manufacturer of M-80’s and other illegal consumer devices. These devices “exploded as soon as they were lit”, apparently while still being held in the hand. While the authors’ interests were peaked by this report, it was not possible to investigate the cause of the malfunctioning fuse because none was available for testing. Many years later, while discussing the accidents at the 1989 PGI Convention, Eldon Hershberger said that he had a small amount of fuse dating back to approximately that time, and the fuse had an unreliable burn rate. He stated that the fuse generally burned normally, but every once in a while the burning seemed to instantly advance ½ to 1 inch. He had purchased the fuse from a hobbyist supplier in the late 1970’s. This sounded like it might be the defective fuse we wished to have for testing. Eldon was kind enough to supply two short lengths for evaluation.


Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 3, (1993-1994), pp 46-50
(K3_46)
Download/Purchase Options :

You must be logged in to purchase or download articles.

Successful Bidding and Performance on Government Fireworks Display Contracts

K.L. and B.J Kosanke

Over the years the authors have had experience with government contracting from both sides: in selecting and monitoring contractors for the government and as holders of government contracts. In this article we would like to share some general information about contracting with the federal government and about contracting for fireworks displays in particular. However, readers are cautioned that there are some differences in the manner in which various government departments let contracts and then monitor those contracts. Thus there is no guarantee that the process, as described in this article, is completely accurate for any particular situation.


Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 3, (1993-1994), pp 41-42
(K3_41)
Download/Purchase Options :

You must be logged in to purchase or download articles.

Electric Matches & Squibs

K.L. and B.J. Kosanke

The terms electric match and squib are often used interchangeably in the fireworks industry. However, there are at least two good reasons not to do this, one technical and one legal. Technically, these are two different items both in terms of form and function. Legally, although both are Class C explosives (Explosives, 1.4g), squibs are on the BATF Explosive Materials List, which invokes all the regulatory requirements normally reserved for Display Fireworks, Blasting Caps and Dynamite.


Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 3, (1993-1994), pp 43-45
(K3_43)
Download/Purchase Options :

You must be logged in to purchase or download articles.

Lancework — Pictures in Fire

B.J. and K.L. Kosanke

ABSTRACT: Lancework set pieces can be one of the most interesting forms of fireworks. If one uses highquality lance formulas, skillfully designed lance figures, provides clever animation, or tells an interesting story, the intertainment value of lancework can reach the heights it should. This article describes the methods used by the authors to design, construct and display lancework set pieces. There are also short appendices written by C. Jennings-White, M. VanTiel, and R. Winokur, wherein they present their views on some points relating to this article.


Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 3, (1993-1994), pp 20-40
(K3_20)
Download/Purchase Options :

You must be logged in to purchase or download articles.

Fireworks Displays — Abnormally Dangerous Activity ? ? ?

K.L. Kosanke

Most of the fireworks display industry is aware of the ruling of the Washington state supreme court, which declared the conducting of fireworks displays to be an abnormally dangerous activity.[1] In part, that ruling was based on their considered opinion that, by their very nature, fireworks displays could not be performed safely. One to be an abnormally dangerous activity is that in the event of an accident, negligence is no longer a consideration regarding liability. In legal parlance this is referred to as “strict liability”. Under normal liability, in order to win a judgment it must be shown that a defendant was negligent (i.e., failed to conduct himself as a “reasonable” person would have under the same circumstances). Thus, if a display operator and crew always do what reasonable persons would, they would not be negligent and would be victorious if sued. (At least this is true in theory.) However, under strict liability, about all that a plaintiff needs to prove in court to win a judgment is that they were injured. Obviously, this is a far easier task, and a situation likely to have ramifications affecting insurance rates and a sponsor’s willingness to put on displays.


Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 3, (1993-1994), pp 16-19
(K3_16)
Download/Purchase Options :

You must be logged in to purchase or download articles.

Explosions and Detonations

K.L. Kosanke

The proper use of technical and scientific terms is fundamentally important for clear and effective communication. It is also a mark of a professional to use the vocabulary correctly. Toward that end, the following brief article is offered. There are a series of notes [a–e] included for additional and qualifying information at the end of the text. However, it is suggested that the article be read first in its entirety before diverting to read the notes.


Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 3, (1993-1994), pp 14-15
(K3_14)
Download/Purchase Options :

You must be logged in to purchase or download articles.

Aluminum Metal Powders Used in Pyrotechnics

K.L. and B.J Kosanke

[This article is an updated, enlarged version of one originally appearing in Pyrotechnics GuildInternational Bulletin Nos. 27 and 28 (1981– 82).]

Of those chemicals used in pyrotechnics (with the possible exception of charcoal) aluminum metal powders have the ability to produce the greatest variety and range of effects. Thus, mastery of the use of aluminum in pyrotechnics offers both a challenge and a reward. In an attempt to assist in achieving that mastery, this article presents information on aluminum metal powders and their use in pyrotechnics. However, the emphasis is on physical aspects of aluminum metal powders, rather than on aluminum chemistry. The subject of specific uses of aluminum in pyrotechnics has been covered by other authors, and numerous references to such articles are given in the last section of this paper.


Ref: Selected Pyrotechnic Publication of K.L. and B.J Kosanke, Part 3, (1993-1994), pp 4-13
(K3_4)
Download/Purchase Options :

You must be logged in to purchase or download articles.