by Osvaldo Tarditti, President of the Reaction Research Society (RRS)and Dave Nordling, Secretary of the RRS
It is with great sorrow that we announce the death of our beloved friend, George Dosa. He passed away at his home on Sunday, August 25, 2019 at 6:15am. He was 96 years old.
George was a long-time member of the RRS and a friend to everyone he met. His personality and knowledge will be missed greatly. But even though he is no longer with us, he is still a source of inspiration to continue the effort to carry the Society forward.
George Dosa was born on November 12, 1922, in Cleveland, Ohio. He moved to Los Angeles, California, when he was 15. He joined the U.S. Navy in 1942 and became an Aviation Metalsmith, 3rd Class. He was shipped out to Guam and later to mainland China in Shanghai where he had his own metal shop until the US Navy left China before the Communist Revolution in 1949.
Returning to the US, he enrolled in the Northrop Aero Nautical Institute then later worked for Aerojet, Gilfillan, Harvey Aluminum, and then NCR. He took night classes at the University of Southern California in engineering and ultimately worked at TRW until his retirement in 1987.
George joined the RRS sometime in the 1950’s at the encouragement of B.J. Humphreys, another giant in amateur rocketry. George’s association with the RRS would be one of his great joys throughout his life.
George Dosa was the first licensed pyrotechnic operator in rocketry in the state of California. He made large contributions to the rules and regulations governing amateur rocketry with the Office of the Fire Marshal in the state of California (CALFIRE). Although the RRS was founded in Glendale in the shadow of what would become the NASA Jet Propulsion Laboratory, the RRS still holds its monthly meetings in Gardena, because of George. It was George that came to the Gardena Community Center (now called the Ken Nakaoka Community Center) and found our meeting place which has served us for decades and to this very day.
George never held office in the RRS executive council, instead chose to mentor, teach and research issues for the society. The office of the Director of Research in the RRS was created specifically for George Dosa. This was a role he held for many years.
He loved being out at the RRS’s testing site, the Mojave Test Area (MTA), and the metal quonset hut still in use today bears his name. George was passionate about taking data in every experiment and documented a lot of his work. A lot of George’s work survives in the RRS archives which have many documents still in need of digital conversion.
George’s love for the society was shown in the many people he mentored and influenced. The RRS is stronger thanks to his decades of patient dedication to amateur rocketry.
The RRS, along with George’s extended family, said goodbye to George on Friday, September 6, 2019 in Rancho Palos Verdes, California. He was given US Navy honors and will be remembered forever by a grateful nation for his service. Many members of the RRS were present to pay their respects and many more were there in spirit and have sent their condolences to the family.
EDITOR’S NOTE: Further expansion of this article will be done as others in the society wish to share their stories of George and his considerable influence on many people in amateur rocketry. The RRS is also grateful to the Dosa family for their help with this article.
The Reaction Research Society (RRS) held its monthly meeting on Friday, August 9, 2019, at the Ken Nakaoka Community Center in Gardena. We were glad to welcome a new member to the society, Drew Sherman. Frank mentioned that the latest educational event with LAPD CSP was going well and that we can expect the next launch event to take place on Saturday, September 21st.
We began our meeting with the call to order and reading of the treasury report. This August meeting would try to catch up on topics intended for past meetings.
 MTA launch events since the last meeting
The first topic on the agenda was discussion of the recent launch events held at the MTA since our last meeting. The RRS hosted Operation Progress at the MTA on July 13th. The launch report for this last event with the LAPD CSP program has already been posted.
UCLA held its second of two high school rocket launch events at the RRS MTA on July 31st. This was supported by Osvaldo Tarditti and Larry Hoffing as the six teams flew and recovered egg payloads using model rockets with “G” sized commercial motors. The event was a great benefit to the young participants and a welcome change of pace as the RRS welcomes model rocketry and amateur rocketry alike.
RRS members, Jack Oswald and Cooper Eastwood, had a launch event at the RRS MTA on August 3rd, delayed 2 weeks from the original July 20th date. The “50 for 50” rocket was built to reach 50,000 feet on the 50th anniversary of the Apollo 11 moon landing. Jack’s large solid motor was impressive as he and his family worked hard at the event to get his rocket ready for flight.
A last minute inclusion was a radio tracking package made by Friends of Amateur Rocketry (FAR) member, Joe Conway. Joe was kind enough to allow his tracker to fly in Jack’s rocket as his device was not operational. Our fellow amateur rocketry enthusiasts at FAR came over to assist in the launch and the RRS was glad to have their participation.
Jack’s rocket weighed in at over 82 lbs with 30 lbs of AP composite propellant in four Bates grains within his booster. With a team of four to six people, the booster and instrumented payload section were assembled and loaded into the rails.
Unfortunately, the “50 for 50” rocket flight was a failure and the booster exploded shortly after ignition. Based on the film footage, ignition of the motor was achieved and the rocket lifted about two to three feet within the rail before an over-pressure event ruptured the booster and destroyed a great deal of the launch rails. No one was injured in the firing, but there was a large amount of clean-up to be done. We were very thankful to all of our attendees for their attention to safety and assistance in carefully gathering for disposal of the unburned propellant scattered from the violent end of this rocket.
Given the extensive damage to the rails, refurbishment will be costly. The RRS is already assessing plans to replace the necessary parts to restore this large adjustable rail launcher very soon.
Jack is preparing a report of his entire build processes and some theories regarding what happened and what could be done better. This report will be submitted to our membership, but Jack will be unable to present his findings in person as he will be leaving for his freshman year at MIT. Even in failure, it’s important to keep good records. The RRS is a scientific society which insists on good record-keeping and sharing knowledge to make each project better than the last.
It was an amazing effort by a group so young. They had great support from many people and sponsoring organizations who donated money and resources to completing their rocket for this test. The RRS was proud to help our members achieve a great learning experience and in time, try again.
Going back to the MTA launch event of July 13, Brian Johnson was able to present a summary of Kent Schwitkis’ trajectory analysis of the Compton Comet alpha rocket flown that day at the MTA event for Operation Progress and LAPD CSP. Kent did a thorough analysis of the optically measured positions of the alpha as it left the rails within the view of the footage taken. Using the video footage taken of their alpha fired from the RRS MTA box rail, careful scale measurement of key landmarks in the background, the software program can make reasonable estimates of the position, velocity and acceleration of the rocket as it is seen and timed frame by frame in the video.
The optical measurement approach provided some direct confirmation about the starting acceleration (95 G’s) and burnout speed (200 m/sec) of the RRS standard alpha flown that day. Kent Schwitkis’ method has great potential. The best course of action would be to conduct further tests of this kind to get a larger data set to confirm the statistical accuracy and variation between similar alpha rockets flown. The society will have this opportunity at the next event planned for September 21st.
 RRS standard liquid and the TAM project
Richard Garcia, our director of research, has created a prototype design for a simple liquid rocket that after some initial trial and error could become a standard project at the RRS much like the alpha and beta have become for micrograin solid propellant. Richard has created a materials list and the society is in the process of acquiring the necessary items and will begin construction of the initial prototype. For now, it is too early to say what this standard design will look like, but as many past members have built their own liquid rockets over the years, the RRS can draw upon a sizable base of past knowledge to create a modest liquid rocket that is both powerful and practical for future members to try.
I have been working with a small group at the Tomorrow’s Aeronautical Museum (TAM) at the Compton Airport. This project has a simple goal of creating a ground testing system to hot-fire a surplus LR-101 vernier motor. TAM has acquired a few of these kerosene and liquid oxygen LR-101 motors which have internal cooling passages and are made for long duration firings. Although the engine is already made, building the necessary regulated pressurization system and valves will be the primary challenge. This work can easily benefit other liquid rocket projects.
 RRS social media improvements
This is a regular agenda topic to be discussed at each meeting with the goal of finding ways to improve our presence in social media platforms and on the internet in general. Bill and Alastair, our two media coordinators, were both absent at this meeting so this topic will return next month as planned.
We’ve had a few new posts on our Instagram feed with recent events. Bill Behenna recommended that on flyers for future RRS events, the addition of a QR code to link back to our official webpage or other important information is something we should do.
 Pyrotechnic operating licensing at the RRS
The RRS has been working with CALFIRE on having more of our membership becoming licensed pyrotechnic operators to better enhance our operations and foster amateur rocketry in general. Osvaldo Tarditti, Larry Hoffing and myself have all been working through the licensing process. We encourage more of our membership to spend the time to prepare their applications and gather letters of recommendation necessary to begin the process. This will be a slow process, but as more pyro-op’s at the RRS become available, more able our society will be to hold events and support other rocketry groups in their projects.
 New RRS alpha payloads
The RRS holds many launch events throughout the year with Los Angeles area schools thanks to our partnership with the LAPD CSP. These events have from six to twelve alpha rockets flown from the RRS MTA at the conclusion of each program but they have empty payload tubes. This represents a great opportunity to fly more payloads.
John Krell has been working on an instrumentation package that can record high accelerations, barometric pressure and capture high speed data all in a compact package that fits in the tiny confines of an RRS standard alpha rocket. There are many commercially available instrumentation packages for model rockets which have larger plastic bodies Given the smaller internal diameter of an RRS standard alpha rocket, many of these great devices simply do not fit. John’s design seeks to make use of the latest instrumentation chips all in a long thin compact package ready for use in the RRS alpha. With luck, his device should be ready for flight at the next RRS MTA launch on September 21, 2019.
SImilarly, Brian Johnson, in partnership with Kent Schwitkis and Compton College, has been working on an instrumentation payload of their own design for the RRS standard alpha. The first flight of his payload on July 13, 2019, was not successful as it failed to start recording. Brian has worked to improve the design, but the fundamental principles were sound. A second flight of this design at our next launch event at the MTA on September 21, 2019, should prove to be successful.
 Discussion of the next RRS symposium
The RRS opened discussion about the possibility of holding another symposium in the next calendar year, 2020. Previously, the society had decided not to hold another symposium after 2019 until two years later for both reasons of cost and resources necessary to conduct the event. While the society has not formally decided whether or not to have a 2020 RRS Symposium, the executive council did decide to study the matter further based on continued success and enthusiasm by past attending organizations.
The RRS will make a decision on this matter before the next meeting. If the RRS does decide to proceed, we must begin preparations in the latter part of the year to allow sufficient time to contact participants giving them time to prepare for a symposium in the spring as was done since our 2017 RRS symposium. Further, full engagement of our membership will be critical to keep this string of successes going strong.
As the meeting adjourned, RRS member, Mohammed Daya showed us the two model rocket bodies he purchased at a Northrop-Grumman swap meet recently. These were built by a retired rocketeer who wanted his hobby to go to another enthusiast.
As these two rockets only need some minor repairs and suitably sized commercial motors to be installed, we hope Mohammed will be able to launch them from the MTA on September 21.
The RRS will hold our next meeting on September 13, 2019. We plan on discussing three very important subjects:
(1) RRS MTA facility improvement plans including a new restroom facility, a new blockhouse and replacement of the large box rails damaged in the August 3, 2019, launch attempt.
(2) Discuss the initial draft of the updated Constitution as presented to our attending membership by the 2020 RRS Constitutional Committee.
(3) RRS decision on the next symposium.
If there are any questions, please contact the RRS secretary.