I have spent the last couple of months researching a way back into model rocketry. My main objective was to fly with hybrid propulsion. Unfortunately, the start-up costs for such a return have proven to be cost prohibitive, as I would be the
only hybrid flier in the state of Alabama. Although the initial thought of being the only hybrid flier in the state was somewhat prestigious, it could also have been deemed a fateful move. Working with a sizeable budget, as I liquidated another hobby to support this return, start-up costs consumed roughly 75% of my funding. My only consideration was to use the Contrail 76mm system, trying to support a variety of loads from K thru M-class flights… this would prove to be
very expensive at well over $2,000. The ground support equipment (GSE) was the second highest cost coming in at $700. Although I have my own nitrous tank, it is not cost effective for its size. My tank is a mere 20 lb capacity tank and would
require me refill often in order to support the large K thru M propulsions systems. This lead me to seek out the “K” sized tank. On top of the tank upgrade, the cost of nitrous has gone up. Add in here, that I still need a rocket tracker, altimeters and a vehicle that will take the Contrail motors, and I have essentially tipped the scales on my hybrid return to rocketry. With sheer disappointment, I am left with no other course of action but to cease further hybrid research and turn my focus towards solid propulsion.
Much has happened since I last posted an update, none of it was rocketry related. I made a lot of new friends, unfortunately they were all doctors. Due to some health issues and advice given to my by one of my doctors, I have given up a quest of any amateur rocketry endeavors that require me to work with dangerous chemicals. Chemicals that I could accidentally ingest, absorb or inhale that could further jeopardize my health. Devastated by the news, I sold off all of the propulsion components for my Gemini project, and even much of the electronics. Luckily the Christmas holidays came up, and I could take my mind away from feeling sorry for myself. Today I have a new vision. Today I am looking at the return to amateur rocketry through an avenue that I should have stayed on when I tried to make a come-back last year; Hybrid Rocket propulsion and design. Although still in the early stages of thought, I am trying to acclimate myself back into hybrid propulsion and design, as much of what I had learned some 8-years ago, was never retained. I also need to find a way to fund my re-entry into this form of rocketry, as much of the components and support for hybrid flight are quite expensive… and due to the rocketry environment being more ‘solid’ friendly, the parts are becoming quite archaic and hard to source.
Enough for now, as I have made this giant leap before, only to fail miserably and retreat… Let’s see where this takes me this time.
Project Gemini Update
All of the major components for the Gemini rocket have arrived. As seen in the photos posted below, the parts groups include a custom Mad Dog Dual Deploy rocket, dual altimeters (dedicated), a Com Spec R-300 transmitter. The vehicle will also include a component assembly from Aero Pack, a motor adaptor ring system that will allow me to adapt 54mm motors into the 75mm motor mount.
The custom Mad Dog rocket has some unique features, many that you will find on all of the Extreme rockets currently on the market; such as the Dark Star Extreme, Wildman Extreme, and the Wild Child Extreme from Wildman Rocketry; as well as the DX-3 Extreme and the Frenxy XL from Mad Cow rocketry. These kits share the Von Karmen nosecone design (w/ metal tip), 75mm motor mount, all built on G12 filament wound tubing. The Mad Dog also shares a feature or two that will be consistant with the upcoming Dominator 4 R2 from Proline Rocketry, as it will come with aluminum bulkheads w/ dual ejection canisters, and an aluminum boat tail retainer from Aero Pack. All of the major components can be clearly seen in the pics below.
I have also received a custom motor order from “ED” at True Core. These are Brand X motors designed specifically for research propellant. The Gemini rocket will be able to fly on any one of these motors which are are 54mm and 75mm in class, varying from 2, 3 and 5-grain in the 54mm and 2 & 5-grain for the 75mm. The Gemini vehicle will be very versatile across a wide range of motor profiles. I will post more motor and propellant specifics in upcoming articles.
This will be the most advanced vehilce I have constructed to date. Never have I flown two altimeters in a 4″ airframe, let alone two dedicated altimeters. My past experience with altimeters, is to share one altimeters across a range of rockets. No more, now when I purchase a vehicle, I will also purchase an altimeters, which will become dedicated to that rocket only. The altimeter will only be removed to replace or clean it. This is a small step in trying to reduce risk of damaging an altimeter(s) by exschanging them to other rockets, thus causing a possible recovery failure. I have mentioned briefly, that much of my efforts now will be to learn and understand the best methods and practices to recover all of my rockets with a 100% success rate. Over the years, my recovery success rate had dropped well below 50%. This is unacceptable, and I am taking steps now to correct this.
There will be more to come as start construction of the Gemini rocket, I can’t wait to get started.
Project Gemini has seen some changes over the last couple weeks. Material selection was the largest hurdle, as I wanted Gemini to be the rocket, not only to be my vehicle by which I make my return to rocketry, but I also wanted the rocket to be more of a rocket, instead of a model rocket. In other words, cardboard airframe and plastic nosecones are out, replaced by G10 and G12 composites . However, as I worked through the selection of materials I began to realise that I was facing many design limitations that could hurt or seriously delay this project. With the selection of G10 and G12 materials comes a new way of manufacturing the design. The tools do not currently exist in my shop. The ability to cut fins and slot composite airframes are processes that I am not equipped to do. With that said, I am faced with two choices; slect cardboard and plastic replacements, which I have decided against, or find a kit that closely matches my design, and custom order it. I chose the latter.
The kit I have chosen to customize, the kit that comes closest to my original Rocsim design of the Gemini is the Mad Dog Dual Deploy from Rocketry Warehouse. I was actually trying to decide between the Dominator 4 and the Mad Dog, and as much as I really like the Dominator, the Mad Dog seemed to be more along the lines of my original desgn. I contacted Rocket Warehouse and asked if I could custom order the kit, and gave them some specs and proposed changes. The fine folks at Rocketry Warehouse happily quoted my order as follows: The motor mount will change from a 54mm to a 76mm; the nosecone is changed to the filament wound Von Karmen nosecone w/ metal tip; the AV-Bay lids have been upgraded to aluminum lids with dual eject charge holders; and the fins have been upgraded from 1/8″ to 3/16″ material. Other than these changes, the rocket met the material design parameters utilizing G10 and G12 compositess. To complete the design, the rocket was ordered with an Aeropac 98/76 boat tail motor retainer and a 54/76 motor adaptor ring set, and a 62″ Star Chute. I wrestled a long while with my selection, as I really wanted to scratch build my Gemini rocket, but I believe that the Mad Dog, in it’s new “Extreme” condition, will be a perfect selection for the project. I am still waiting on the order, as the Rocketry Warehouse requested two weeks to complete the change requests.
With the motor mount selection, coupled with the motor adaptor rings on the Gemini, I will be able to utilize all five motors that I have purchased from Ed at Tru Core; a 2, 3, & 5-grain 54mm set and a 2 & 5-grain 76mm motor set. With the design parameters nearly complete, I should be able to test the rocket and propellant on the 2-grain motors, and really let them fly on the 5-grain motors. As of right now, the end goal for Project Gemini is 2-miles… there is much to do before these goals are realized.
I have completed two design parameters for this vehicle; there will be two dedicated Strato Logger altimeters for redundancy, and a Comm-Spec RF tracker for a recovery locator. Because many of my mass exoduses from rocketry have been recovery failure related, I am making every effort to ensure that recovery will be top priority so as not to repeat past mistakes.
This was just a brief update to the project, once parts of the rocket have arrived, and I have started construction, I will update more on the build and testing, that is sure to sure follow.
August came and went without much of anything to report…except that I finally attended my first rocket launch in nearly 3 1/2 years. I was just an observer, not a participant, as my goal was to just get to the field and get re-acquainted with many of my rocket friends, as well as meet some new ones. Other than a severe sunburn, the event was awesome…and just as I remembered it. Also, August was a month of placing orders for rocket related parts and supplies, as I continue to make my return to rocketry. So yes, mothing to much to report from August… Did I mention that I also had gallbladder surgery(?) So on with September:
Many of my purchases have arrived, with only a few outstanding items. I have a new rocket tracker from Comm-Spec, model #R-300. I ordered the unit with channel 327 specified. I als have three new alitemeters from Perfect Flite, they are all Stratologger units, which are destined for two different rocket projects. Speaking of rockets; along with the Project Gemini, I will also be designing and building a scratch built rocket from a “scratch builders kit” that I picked up recently. It is all G12 and G10 materials, except for the nosecone, which is plastic. The kit is based on the 2.56″ dia airframe size, one of my favorite dia airframes for model rocketry. More to come as I start serious designing for this kit.
Still outstanding from my purchases last month are a custom rocket kit from Rocketry Warehouse, and a custom rocket motor order from Tru-Core. These are very exciting purchases for me, and I will hope to report on these items once they have arrived. I like the “custom” and “special order” as these are clear indicators that these products meet my specs and will fit my design. Again, more to report once these items have arrived. That’s it, nothing much to report, but worthy of an update… if only to prove to myself, that I Am Back this time!!