62″ Mortar Design, Mathematical Model and Results
Tent 1 | Seminar
Saturday, 02/17/2024, 12:30 PM – 1:15 PM
Presented by: Eric Krug, Jim Widmann
A team was formed in North America to attempt the launch of a 1,575 mm aerial shell with the goal to obtain a new world record. The design of large shell casings, internal pyrotechnic components, and the engineering design of the required mortar has previously been published.
The first attempt on February 9th, 2019, resulted in a malfunction of the shell in the mortar producing a large flowerpot failure. The resulting integrity of the mortar and the failure mechanism of the shell were of great concern. Undeterred, the team immediately began work on a second attempt that resulted in a successful launch on February 8th, 2020.
This paper will review the analysis of the mortar after the failure, the process of rebuilding the mortar, additional engineering analysis, and changes to the shell design.
A successful internal pressure profile was obtained and will be compared to the previously published internal and external ballistic mathematical model.
Additional Session Information:
- Beginner Friendly: Not Applicable
- PPE Required: Not Applicable
- Age 18+: Not Applicable
- PIT Crew: Not Applicable
About Presenters
Eric Krug
Eric Krug graduated in 1985 from Kansas State University with a Bachelor of Science degree in Electrical Engineering Technology. He then moved to Loveland Colorado and specializes in electrical and mechanical product design. He owns his own development company that includes a full machine shop. Eric also teaches advanced CNC machining at the local community college. Eric has been very active as a licensed professional pyrotechnician since 1981. He has had the opportunity to compete in the Montreal International Fireworks Competition twice and is the lead pyrotechnician for many large pyro productions. Eric is very active in the PGI and other groups. As a part of his product development company, Eric also produces a wide variety of tools for the pyro industry.
Eric is also an accomplished musician and plays a variety of instruments.
Jim Widmann
Jim Widmann is a long-time fireworks enthusiast and professional. Jim has shot shows for most of the fireworks companies in the Northeast US and in 1985 started a fireworks display company based in Connecticut. He was a founding member and president of the Connecticut Pyrotechnics Association.
As a kid, July 5th was Jim’s favorite day of the year because he would find leftover dud fireworks from the neighborhood displays and cobble them together into something new and of his own making. Jim is a 30+ year member of the PGI and has competed and won in many of the display shell categories. He has a CT display operator’s license and is also licensed in CT as a pyrotechnic manufacturer. Jim is widely known as the inventor of the WASP automatic shell pasting machine and has sold hundreds of these machines in over 22 countries. In recent years, Jim has successfully built and shot world record shells (up to 62”) in North America and the Middle East.
