By Timothy Raneyâ€¦Bald Engineer Guy with Glasses
Hello! I guess itâ€™s time for another one of Timâ€™s strange singularly individual science projects again. This time weâ€™ll discuss the details and process involved in building a rocket for my Level-1 high power certification under the National Association of Rocketry (NAR) rules. Well, letâ€™s start at the beginning, shall we?Â
Let me first say I am a true rocketry novice. Sure, Iâ€™ve built a few rockets and a learned a lot in the last four years. Though beyond practicing the requisite safety procedures, I am certain many of you can do this work better. What I will describe is how I did something. My way is not the only way or even the best way. So, read on, but donâ€™t take my words at face value. There are many excellent online resources available on this topic. Check your local library too.
Interested in rocketry since I was about 10 years old, I first made small â€œbottle rocketsâ€ with cardboard tubes from coat hangers, clay and a few grams of home-made black powder. Even as a kid, I followed the safety rules as I understood them at the time. However in retrospect, I was very lucky too. With the availability of reliable rocket motors on the market today, itâ€™s not a good idea to make your own motors. With that warning aside, a good friend of mine got me interested again in rocketry in 2009. So, I joined the Heart of Virginia Association of Rocketry (HOVAR). We are Section #704 in the National Association of Rocketry (NAR). I soon found out there was much more to the hobby than the little model rockets we buy for our kids.
And as in most hobbies, you can spend a few dollars for a model rocket or spend thousands for rockets that match the complexity and performance of NASA rockets used to loft scientific payloads. Though still a novice and new to the hobby, I started with the Estes-Cox â€œStormcasterâ€ model rocket with a D-motor and progressed to larger rockets using the more powerful F and G-motors. One such rocket was capable of half-mile high flights. Many of the larger rockets go much higher routinely. Of course, we must get permission from the Federal Aviation Administration (FAA) in those instances, but thatâ€™s a routine matter. We get FAA clearance every time our club launches (usually monthly). Itâ€™s not a big deal. With that introduction, this series of articles will describe the design and construction of a high power rocket intended for experimental purposes.
National Rocketry Associations
Low, medium and high power rockets are routinely and safely flown throughout the United States by members of the National Association of Rocketry (NAR) (www.nar.org) and the Tripoli Rocketry Association (TRA) (www.tripoli.org). Both organizations promote the safe practice of rocketry as a hobby and scientific pursuit in many ways. They have excellent resources for educators and rocketry enthusiasts. Iâ€™ll give you an overview of these two organizations here, but I highly encourage you to visit their respective websites for more details.
National Association of Rocketry
The NAR is a non-profit scientific organization dedicated to consumer safety, youth education and the advancement of technology in the sport rocketry hobby in the United States. The NAR was founded in 1957 – the oldest and largest sport rocketry organization in the world. Â With over 5100 current members and 125 clubs across the country, over 90,000 sport rocket modelers have joined NAR since its founding. NAR supports all aspects of safe sport rocket flying, from small models to large high power rockets. It is a recognized national authority for safety certification of consumer rocket motors and certification of high-power rocket fliers. NAR is the author of safety codes for the hobby – accepted by manufacturers and public safety officials nationwide.
Tripoli Rocketry Association
Tripoli or TRA is a non-profit organization dedicated to the advancement and operation of amateur high power rocketry. Current membership includes about 4000 members and 100 prefectures (clubs) worldwide from the US and 22 other countries. TRA began in 1964 as a group of high school students who formed a science club focusing mainly on astronomy and rocketry. TRA promotes high power rocketry as an educational, safe and exciting hobby enjoyed world-wide. Tripoli Rocket Association is dedicated to advanced rocketry – pushing the envelope of civilian rocketry in a safe and scientific manner. Itâ€™s worthwhile to note high power rocketry has an excellent track record, with safety codes to protect participants, viewers, land owners and the public.Â
Experimental Rocket #10 â€“ The Beginning
This particular rocket is intended to meet the Level-1 NAR certification requirements. Though outwardly simple in design, designing and building a rocket from â€œscratchâ€ entails knowledge of the underlying principles and the mathematics needed achieve a viable design. However, the required knowledge is nothing out of reach for those interested. After all, if I can do it, anyone can. Additionally, I will use materials intended for this application based on some understanding of the stresses involved.
Next time, weâ€™ll discuss the initial design process, to include determining the rocketâ€™s overall dimensions and fin design.