Sport Rocketry

38 MAY/JUNE 2024 SPORT ROCKETRY Sport Rocketry is looking for full length articles with high quality photos/illustra- tions. Articles such as building projects, technical topics, and "how to" subjects are needed! Sport Rocketry is also looking for addi- tional, shorter, perhaps less technical, but still substantive articles. Examples of short- er articles that have been published include: outreach events, local or regional launches, and simpler builds. Feature article authors may receive up to $350 aer publication of their article. Au- thors of other articles may receive a free year's NAR membership. Decision on pay- ment or membership status is based on the quality and subject matter of the article and is at the discretion of the Periodicals Com- mittee Chair, Mark Bundick. Questions about article payments or membership ex- tensions should be sent directly to Mark. Do you know someone who has an in- teresting project you think would make a good article? Send your suggestions, along with contact information on the project owner, to Periodicals Commit- tee Chair, Mark Bundick at mbundick@ comcast.net for follow up. WE WE PAY FOR PAY FOR ARTICLES! ARTICLES! WE WE PAY FOR PAY FOR ARTICLES! ARTICLES! Technically I violated an assump- tion made by Barrowman: this is that the curve of the nose should be continuous without any discontinuities. As the shoul- der is a discontinuity, I didn't follow this assumption. Center of Gravity Location For the final rocket, the CG was located at 0.4 times the nose length with a motor inserted, meaning I had a static stability margin of 0.05 times the nose length. In my experience, commercial rocket kits that rely solely on body forces rather than fins to keep the rocket stable utilize metal nose weight to move the CG for- ward enough. Safety considerations of us- ing metal nose weight in your rocket will stand here without comment. However, from a purely engineering perspective a flying nose shaped rocket needs to have a CG located relatively far forward with little volume and, as a result, it's very difficult to have a statically stable rocket that doesn't use metal nose weight. Since I was building a flying nose as my upper stage, I could get away with a small- er motor compared to what I would have needed if I was building a single stage fly- ing nose. So, I didn't need as much nose weight, but I still had to use metal to get the job done. Rear Ejection Last on the list is rear ejection, and no article on an upper stage flying nose cone would be complete without some com- mentary on everything that go can wrong with rear ejection, which I used out of ne- cessity for the project. e completed Upper Stage Flying Nose rocket on the pad.

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