High Power Rocketry in WV
Click here for the link to our club HPR engine order form (as of 6/21/2015: hopefully it permanently remains the right link). Orders will be made periodically as noted at club meetings.
The WV Rocketry Association is committed to supporting its members in obtaining high power rocketry (HPR) certification if they so desire. To this end, our Level 1 Certification chairman, Chris, has filed for and obtained HPR permission from the FAA for our Mylan Park launch site. As the club president and the FAA designated Range Safety Officer (RSO), I have some suggestions for members as they work their way up the HPR ladder.
1. You may want to use a level 1 composite kit (such as the fiberglass Hawk from MadCow) or if you are making your rocket from scratch, over-engineer it using TTW (through the wall) fins, epoxy for all joints, and heavy-duty shock cords to ensure that you don't fail your certification because your rocket was damaged.
2. Have other members double check your design and evaluate your rocket for safety concerns. For example, I learned that my rail button placed at the upper centering ring was positioned a bit too low, and should have been placed at CG. It was an easy fix, but one that I am glad someone pointed out.
3. Use a simulator such as RockSim to validate your rocket's stability and to determine the most appropriate engine. Just like we do with low power rockets, we should ensure our design is as accurate as possible (by weighing components and the final rocket), running simulations with numerous engines, and testing a variety of environmental conditions. Additionally, make certain that your rocket will be leaving our 8' launch rail with sufficient velocity to be stable, that you have adjusted your ejection delay to allow for the optimum ejection (typically at apogee), and you have sufficient size or numbers of parachutes. Here is an example of the simulation data for my quite heavy level 1 rocket. Be prepared to share this data before launching.
4. WV Rock follows the safety guidelines of the NAR with respect to pairing the proper engine with your rocket. While there is no given weight limit for HPR, the NAR Safety Code sates, the rocket max weight should not exceed 1/3 of the total impulse. For rockets under 20 lbs I suggest dividing avg impulse by 25 to determine maximum rocket weight. For example, let's look at my H400: 400/25 yields rocket max weight ~ 16 Lbs. Since my rocket is only 7 pounds, I feel confident that I am safe using this engine. To be safe, you should always look at your engine's thrust curve. A good source of this data is www.thrustcurve.org. I can't recommend enough, that you should read more on this topic when you have time. Visit this great discussion on the Rocketry Forum.
5. And remember, as a club we want to ensure that our launches are both safe and by the book. Anyone can make a mistake so let's follow the NASA motto: "If it's not safe, Say So!"