Projection Criteria for Insensitive Munitions and Hazard Classification

This project has resulted in a paper that will be presented at the IMEMTS in Nashville, US (12-16 September 2016). The abstract of the paper is given below:

“The origin of projection criteria for Insensitive Munitions and Hazard Classification was investigated. The distance-mass relations were reproduced using TRAJCAN trajectory analysis by using launch energies of 8, 20 and 79J and calculating the maximum impact distance reached by a natural fragment (steel) launched from 1 m height. The analysis shows that at the maximum throw distances, the impact energy is generally much smaller than the launch energy. For the launch energies of interest, the height reached by the projectiles is not enough to reach the terminal velocity before impacting the ground. Using maximum distance projections, new distance-mass relations were developed that match the criteria based on impact energy at 15m and beyond rather than launch energy. For near vertical projections the impact distance does not provide any information about the launch energy or impact energy. High velocity shallow trajectories can result in high impact energies, but collected data may be unrealistic due to ricochet effects. The smallest projectile masses in the distance-mass relations are in the transition region from penetration injury to blunt injury. For this reason, blunt injury dominates the assessment of injury or lethality. State of the art blunt injury models predict only minor injury for a 20J impact. For a 79J blunt impact, major injury is likely to occur with a small probability of a lethality. MSIAC recommends changing the distance-mass relation that distinguishes a munitions   burning response to a 20 J impact energy criterion at 15 m.”                      

Comparison between distance-mass relations in the UN Orange Book and trajectory calculations for various types of fragments.

A more detailed overview of the results has been described in MSIAC Report O-168. Interested parties can download the paper and report through those links:

As this topic has the attention of many international colleagues we’re looking forward to interesting discussions at the conference.

 

News categories

Accident reporting Events Industry & technology Meetings of interest Munition Safety Awards Newsletters Other Patents Survey