Blackwell 1Cody BlackwellMrs. CorbettAP English Lit/Comp18 April 2012 High-Power Rocketry “Research is what I am doing when I don’t know what I’m doing.” It may surprise youthat I began this presentation with that statement, but I am only repeating a quote from ournation’s most celebrated rocket scientist, Dr. Wernher von Braun. Through the Army BallisticMissile Agency (ABMA), Dr. von Braun and an extremely bright team of engineers andresearchers revolutionized America’s defense and space exploration technology as we knowthem. ABMA’s research proved most instrumental to NASA’s Apollo program, but, as with anysubstantial scientific strides, the program had its flaws. More specifically, my research paperdiscusses the events leading up to Apollo XIII and how Jim Lovell, Fred Haise, and Jack Swigertsurvived for nearly six days after two oxygen tank explosions in the command module. I plan tostudy aerospace engineering, and in keeping with the problem-solving spirit, I focused on theingenious valve NASA engineers developed from duct tape, plastic bags, and cardboard thatsupplied the three astronauts enough oxygen to return safely home. One might ask, “How can Apollo XIII possibly relate to high-power rocketry?” When Ifirst received instructions for this project, I considered researching techniques for integratinggravity-fed cooling systems into nuclear plants in the wake of the Fukushima Daiichi disaster butruled it out after assessing its practicality. Building on this practicality, I realized it made muchmore sense if I built on my prior experiences, namely in amateur rocketry. I have been a memberof Creekview Aeronautics Club for the past four years, and our teams have only used relatively
Blackwell 2low-impulse engines in our rockets for Team America Rocketry Challenge. High-power rocketry(HPR), on the other hand, is an entirely different ball game, and I chose to build and launch ahigh-power rocket specifically because it requires meticulousness and considerably more timethan anything the Aeronautics Club does. Accordingly, I encountered an issue I will discussmomentarily which presented an almost project-ending conundrum requiring me, like MissionControl, to work with what little supplies I had. As I learned from members of Southern Area Rocketry (SoAR)—our local NationalAssociation of Rocketry (NAR) chapter—and namely Mr. Todd Sharrock and Coach Tim Smyrl,a HPR certification is a prized possession among hobbyists and university clubs. For example,NAR Level I certification (my goal) authorizes flight privileges for rockets weighing over 53ounces (3.3 pounds), with total impulses between 160.01 Newton-seconds and 640 Newton-seconds, and/or engines not classified as “model rocket motors.” I figured if I could push myselfto achieve Eagle Rank, building and flying a high-power rocket for said authorization would beno problem. But like the trail to Eagle, this project required a dedicated mentor, an accountabilitycoach who would scrutinize any changes I made before approving them. As a charter member ofthe Aeronautics Club and a team captain for the past three years, I know both Mr. Sharrock andCoach Smyrl well. However, I selected Mr. Sharrock because he taught my freshman biologycourse and our lunch periods happened to coincide this year. Over the past seven months, wemet regularly to discuss design options, component suppliers, and any problems I encounteredalong the way. Consequently, the essence of engineering commands careful consideration andconsultation before any project commences. For several days in December, Mr. Sharrock and Idiscussed his and Coach Smyrl’s successful Level I designs as well as reliable component
Blackwell 3vendors. Finally settling on Public Missiles Limited (PML), I began designing my rocket usingApogee Components’ RockSim 9.0 software, basing the prototype off a PML parts list in thesoftware’s database. I simultaneously researched high-power rocket plans and stumbled across arecovery system I had never seen. Since the Aeronautics Club’s inception, we have attached one parachute each to ourrockets’ payload and airframe sections, allowing the two to return separately to the ground.However, the system I found and eventually utilized is a single-chute design using a piston thateliminates the need for a black-powder ejection charge. This system allows for the parachute tobe linked with the piston and nosecone by a shock cord and stored without any wadding betweenthe piston and the nosecone; the reloadable motor’s delay forces the piston, parachute, andnosecone out of the tube, keeping all parts of the rocket together during its descent. The onlyflaw was that I could not use a launch rail system like Mr. Sharrock’s rocket because the guidepins would obstruct the piston. Regardless, I showed Mr. Sharrock and Coach Smyrl, who bothheartily recommended it because they have never tried it themselves. Regarding the rest of therocket, I incorporated the same motor mount design we use in Aeronautics Club with theexception of the motor retainer, which NAR strongly encourages hobbyists to use for high-powerrockets, and the number of fins (three instead of four). I settled on slotted phenolic tubing, ahardened parabolic nose cone, and fiberglass fins so, as Mr. Sharrock pointed out, I would atleast have something to show in case of a catastrophic failure! Thankfully, all of the parts shipped together over Christmas break. Around that time, Ialso researched the different types of reloadable motors supplied by AeroTech ConsumerAerospace and Cesaroni Technology, Inc. Again, my membership in the Aeronautics Clubexposed me to AeroTech reloadable motors; however, our brand new reloads were not
Blackwell 4performing well at the time, and Cesaroni seemed to offer a much higher-quality lineup of 29mm-diameter motors for substantially lower prices. Using RockSim-generated flight predictionsfor comparable motors and data sheets provided by AeroTech and Cesaroni, I determined theCesaroni H87-12A, with an average thrust of 87 Newtons and a 12 second delay, was mostsuitable for my certification purposes. Assembling the rocket did not prove too difficult, thanks to my prior experiences, and Istarted from the bottom up. The motor mount consisted of two customary plywood centeringrings, one of which had a slot cut into it so I could glue the bottom nylon shock cord directly tothe motor tube to link the mount to the piston. Additionally, I positioned the centering ringswhere the fins would fit snugly between the rings in their respective slots. On a recommendationfrom Mr. Sharrock, I used marine epoxy to adhere the motor mount inside the body tube and thefiberglass fins in their slots. I allowed the epoxy to cure before tying the bottom shock cord tothe piston, and from there I looped and knotted the top shock cord onto the parachute and linkedit to the piston. At this point, I believed I was almost finished with the rocket until I realized I had notintegrated an altimeter section in my original design. On a typical TARC rocket, the payloadsection includes an altimeter compartment, but I completely neglected the fact that my projectproposal contained an altitude requirement for my rocket. The first week of March, Mr. Sharrockand I started brainstorming about the altimeter section design. We thought we had devised adecent setup consisting of PVC tubing and an eye hook until I actually purchased the supplies. Itturned out that it would be impossible to access the altimeter because both ends of the PVC pipewould have to be sealed in ordered to function correctly. Since I did not want to spend any more
Blackwell 5money, I finally came up with the current design, which essentially extended the nosecone as analtimeter compartment. Amazingly, the same week I redesigned the rocket, SoAR announced it would berescheduling its “Georgia Rockets in the Sky” (GRITS) launch for Saturday, March 31st, atTurfSouth Sod Farm in Lilly, GA (three-and-a-half hours away), instead of April 14 th at acornfield in Ranger, GA (an hour-and-a-half away) because the cornfield owner sold his farm inFebruary. Since the 31st was the beginning of Spring Break, I seized the opportunity andcompleted the rocket ahead of time. Regardless of the altimeter issue, the most significant obstacle of this entire projectproved to be not the rocket itself but Mother Nature. The Thursday before GRITS, I contactedSoAR’s president, Mr. Jorge Blanco, who assured me the launch would continue as long as theforecasted rain chance remained low. My dad and I got up early that Saturday to drive to Lilly,but we had not reached Macon before the sky clouded over. The weather only worsened thefurther south we drove, and we finally arrived around 10 A.M. to torrential downpours and adangerously muddy driveway to the launch site. Mr. Blanco informed us that he and the otherpeople present planned to wait until noon for the rain to cease. Dad and I slept in our truck untilabout 11:15 A.M., constantly receiving weather updates from my mother whenever phonereception was available. Around this time, I remembered Coach Smyrl talking about a club inTalladega, AL, that hosts launches at the end of every month. I found what I thought was aphone number and address for the club (Phoenix Missile Works, or PMW), on the NAR websiteduring one of the reception spurts, and informed Mr. Blanco of our plans. Unexpectedly, he wasvery adamant that I should do whatever I could to get my certification flight that day and wishedDad and I luck!
Blackwell 6 Using our trusty GPS, Dad and I set out back toward Byromville before we headednorthwest toward Columbus. During a pit stop in Montezuma, I figured out that the GPSdisplayed our expected time of arrival at 3:30 P.M. …Central time, meaning we had a four-hourdrive ahead of us. As far as getting to the address on the website, the drive was fairly uneventful,although we passed through Fort Benning, and I got to see more of east-central Alabama than Iever thought I would. Following the GPS, we drove to PMW’s registered address, which turnedout to be the treasurer’s home in Ashville, a small town outside Gadsden and the absolute wrongside of Interstate 20! Dad and I drove into Downtown Ashville about 4:30 P.M. Central time, andwhile I called Mr. Sharrock for directions, Dad logically found the fire station and asked thefirefighters for directions. As it turned out, we had driven about 45 minutes out of the way, butboth Mr. Sharrock and the Ashville firefighters were able to access PMW’s website and get usdirections. We arrived at PMW’s cornfield around a quarter after five only to find out that I hadto register with Tripoli Rocketry Association to be able to launch. However, I managed to meetsome of the most helpful people on earth there, and luckily my “emergency” money covered themembership fee, and I placed my rocket on the pad in under 30 minutes. As if there were butteron the launch rod, the rocket lifted off and soared into the Alabama sky to the cheers of my swiftacquaintances. The ejection charge performed flawlessly, and the rocket floated gently down tothe field; Dad and I spent about 20 minutes looking for it, though, because the parachute landedin a puddle. I triumphantly carried the completely unscathed rocket back to the PMW tent for afinal evaluation. To my surprise, the PMW folks informed me about the certification reciprocities betweenTripoli and NAR, so in effect I became a member of national and international rocketryorganizations while gaining significant privileges from both. On the other hand, I expanded my
Blackwell 7amateur rocketry experience into a realm that falls more under engineering research andsimultaneously dealt with likable people along the way. As an added bonus, I essentiallysolidified my near-obsessive attention to detail, but most importantly, I got the opportunity tospend the entire day with Dad and truly show him how interested I am in studying aerospaceengineering as I enter Georgia Tech this coming fall.