by Dave Nordling, Reaction Research Society, edited by Andrew Cortopassi, Secretary, Reaction Research Society
We held our monthly meeting of the Reaction Research Society (RRS) by teleconference on Friday, July 12, 2020. Our treasurer, Chris Lujan, and our vice president, Frank Miuccio, called the meeting to order.
Since June 2020, we have made the teleconference feature a permanent part of all future meetings even after we ultimately return to in-person meetings at the Ken Nakaoka Community Center in Gardena. Teleconferencing has allowed the RRS to better unite our far-flung membership from around the Los Angeles and neighboring areas and even those on travel.
Due to the restrictions imposed by the continuing pandemic, the next RRS symposium will be held early next year in 2021. This was decided by the membership at the prior June 12 meeting. Frank has not been able to schedule a date, but the society plans to hold the event a little earlier in the year (March 2021) than what was done in the prior events. We remain optimistic that we can have a full exhibition and speaker series while adopting appropriate precautions.
Osvaldo, Larry and Dave became licensed pyrotechnic operators in rocketry for the society as of one year ago. By law, this means that with the renewal of their annual license they can provide reference letters, wholly at their discretion, to other members seeking to pursue their own application to becoming a pyro-op. The society roster of pyro-op’s is growing and this is good for both the society and amateur rocketry in general. We have enjoyed the support of the California State Fire Marshal’s Office (CALFIRE) for many years and this has been helpful as we educate a new class of members in becoming responsible members of our hobby. The more people know the law, the safer our community will be and the stronger our voice with the state becomes.
Dave Nordling announced his intent to become a rockets first-class pyro-op and will begin preparing his application. Jim Gross, one of our pyro-op’s at the society offered his advice to all seeking their license that it is an important responsibility to uphold the law and protect the safety of everyone above all else. The state exams are geared towards verifying a licensee understands the numerous hazards and safety concerns in addition to the state licensing processes and reporting requirements. Every pyro-op must personally vouch for the person they are recommending. This is often done by mentoring, apprenticeship or some form of repeated skills demonstration before the licensed pyro-op to show the applicant is knowledgeable, confident, mindful and vigilant in the safe handling of all operations and the people around them. It is at the sole discretion of each pyro-op what their standard will be. CALFIRE is also very helpful to those having questions about the process.
Waldo Stakes is holding a memorial for Mad Mike Hughes on Saturday, July 18, at noon, at the 247 Cafe in Lucerne Valley, CA. Some of our members expressed interest in attending to pay their respects to Mike’s family and friends. Mad Mike was killed on February 22 this year in the last flight of his self-built steam rocket outside of Amboy, California.
The RRS will be holding a launch event at the MTA on Saturday, July 25th. This event will be for RRS members only and will be the first launch event held since the onset of the COVID-19 pandemic in the United States in mid-March of this year. Many have expressed their concerns in holding this event given several of or members are in at-risk categories either themselves or from within their household. The counter-argument has been that given the wide open spaces around the MTA and the imposition of social distancing and wearing masks at all times, member safety can be maintained. The society consensus was to proceed with the 7/25/2020 launch event.
Three micrograin alpha rockets and a beta will be launched at this 7/25/2020 event. John Krell will have built several high-speed datalogger prototypes that can fit within the tight confines of these alpha and beta aluminum payload tubes. His earlier prototype datalogger was able to quickly and adequately sample the extremely high acceleration of an alpha at takeoff, although the 50G sensor range was exceeded across several consecutive samples. The initial datalogger prototypes were recovered intact and could be reused. Based on this success he will use a higher ranged accelerometer that will add greater detail to our knowledge of the micrograin rocket trajectory and provide additional data about apogee altitude and infer the rate of deceleration from impact.
Dave Nordling will also have two of the standard steel alpha nozzles with their internal flow paths ceramic coated. This high temperature coating is used in the racing industry for piston coatings to extend their life. A few years back this same coating from Specialized Coatings in Huntington Beach was proven on a recovered alpha nozzle showing zero erosion at the throat so we are confident of a repeated success. Also, one of the alphas will use a longer propellant tube (4-foot) than what is the standard (3-foot). We hope John’s dataloggers are able to capture good data from each of the alpha flights for valid comparison. Also, capturing the trajectory of a beta rocket will be another important addition to the society knowledge base.
We discussed some of the history of different micrograin rocket experiments throughout the many decades of the society by several members. Jim Gross offered to summarize his recollection of the many micrograin experiences into an article for RRS.ORG which will be posted soon we hope.
Larry, Dave and Osvaldo have made a second rocket ready for the Contrails H222 hybrid motor. The nitrous oxide bottle should be re-charged and weighed in preparation for the launch event. The recovery system has been added and reloading of the aluminum motor housing with an ignition system and hybrid fuel grain is the only step remaining. Improvement to the igniter system was necessary after observing the high speed camera footage which will attempt to better sever the nylon filling line at the floating injector. It was also recommended to add a small amount of paraffin wax to the forward end of the hybrid plastic fuel grain in an attempt to start the burn a little hotter when the nitrous oxide starts to flow. Hybrid motors have been used successfully in model rocketry events but they have been known to be difficult to ignited and operate reliably. It is the team’s intent share our learning with the society as we work toward success.
It was at this point, the discussion turned to oxidizers in general. One of the earliest projects at the RRS was a rocket-grade hydrogen peroxide (H2O2) monopropellant liquid that was built and flown in the 1950’s. Hydrogen peroxide was explored again at the society many years later in a project to re-fly a monoprop rocket system. Recent information was gathered from Peroxychem on the properties, handling and safety precautions required with having of rocket grade hydrogen peroxide. As expected, the cost per volume of 90% HTP was very high and likely beyond the budget of an amateur project using anything more than a gallon. The membership felt that there wasn’t sufficient interest in restarting a peroxide project, but some kind of summary article of peroxide properties and a collection of different members experience might be interesting.
Jim Gross mentioned his past experiments with nitric acid and its hypergolic reaction with furfuryl alcohol. Regardless of the specific oxidizer, cleanliness and material compatibility of all wetted surfaces is of paramount importance in all experiments and projects. Many people appreciate these hazards when it comes to liquid oxygen, but may not similarly appreciate the hazards with other oxidizers like nitrous oxide and caustics like nitric acid. All oxidizers, even sulfur, must be treated with studious care and respect.
The 2020 Constitutional Committee is still due to present their draft for society membership review and comments. An overview presentation will hopefully be made at the next meeting in August. Updates to the language and policies have been needed for years in order to better describe how the society operates. Ratification by the executive council should follow once all administrative members have had a chance to make their concerns known to our society.
In closing, Wolfram gave the society an update on his gasoline-fueled ramjet project, the Gas Guzzler. He is making improvements to the flow path to enhance mixing and will continue with his benchtop experiments and analyses. He is making progress but will not attend the 7/25/2020 due to the extreme heat in the Mojave desert.
Jim Gross reinforced this concern for all members to protect themselves against heat exhaustion while attending the MTA event. Air temperatures can easily exceed 110 F at the peak of the Mojave afternoon. Bringing a cooler with ice and cold beverages is essential as is sunscreen, a hat and light desert clothing. Even those who have adapted themselves to the desert summer must take these precautions and be mindful of the condition of others.
We adjourned after 9PM as some of our members were retiring for the night. Our in-person meetings must contend with the community center closing at this time, but with our meetings done virtually we can enjoy the extended meeting time together. The next meeting will be again held by teleconference on Friday, August 14th.
Please contact the RRS secretary if there are any questions or concerns.
All members are responsible for keeping their contact information with society up to date and staying current on their annual dues with the RRS treasurer.