A Tribute to Mr. George Dosa

by David Crisalli, Reaction Research Society


Some time in October of 1966, I had hitched a ride and gone down to an RRS meeting in Gardena. I was 13 and still in the 8th grade. At that meeting, I met Mr. Dosa for the first time. I met several other RRS members that evening, but Mr. Dosa was the most memorable. He was warmly welcoming, very enthusiastic about rocketry as a field of study, and also excited about having new students like me join the Society. 

As I attended more meetings and began to get involved in designing and building rockets, Mr. Dosa was always ready to offer help of all kinds from the loan of technical documents to the manufacturing of parts on the lathe and other tools he had in his garage. I spent many an enjoyable hour with him making steel nozzles, aluminum adapters, and fiberglass nose cones.

At one particular meeting in 1967, Mr. Richard Butterfield showed a 16 mm film of a hydrogen peroxide liquid mono-propellant rocket built and launched by RRS members David Elliot and Lee Rosenthal some 15 years before. I was completely captivated as I watched the two high school students in the film machine parts, fabricate sheet metal components, static test a liquid rocket motor in Mint Canyon, and then successfully launch the rocket in the Mojave Desert. Mr. Dosa saw my interest and enthusiasm and talked to me at some length about liquid rockets after the film. Then he asked if I would like to see the one he was working on. I jumped at the chance. 

The RRS meetings in those years were held in an old, small, wooden building on an isolated piece of property owned by a division of Pratt & Whitney in Gardena. It was really a shed but the RRS had been given permission to hold its monthly evening meetings there and store some of its equipment there. On the same piece of property, some 50 or so feet away, was a slightly larger wooden structure. Although larger, it was more of an empty garage and was not as suitable for meetings as the smaller building. When I told Mr. Dosa I would love to see the liquid rocket he was working on, he led me out of the meeting building and across the dark space between the buildings. It was probable nearly 10 PM by this time and there were no lights in the areas around either building. 

As Mr. Dosa opened the door into the very dark second building, he told me to wait there until he could turn on the light. “The light” was a single low wattage bulb hanging on a wire from the high ceiling. When the light came on, even in that dim glow from a single bulb, what I saw took my breath away. There, lying horizontally on a plywood table, was a bi-propellant liquid fueled rocket with the upper half of the skin removed. All of the tanks, plumbing, bulkheads, stringers, and longerons were precisely made and beautifully assembled. The rocket was more than 15 feet long and about eight inches in diameter. It was designed, Mr. Dosa explained, to run on 90% hydrogen peroxide and ethyl alcohol. I marveled as each piece of the structure and propellant plumbing was explained to me. The design was also unique in that Mr. Dosa had made the fuselage octagonal rather than round. This left him “corners” inside the rocket skin that he had used to run plumbing and wiring. The beautifully made fiberglass nose cone and boat tail were both round and the structure smoothly transitioned from octagonal to round at both ends. Mr. Dosa, a master at many fabrication techniques, had fashioned incredibly precise sheet aluminum sections that perfectly mated with the octagonal structure on one end and the perfectly round nose and boat tail on the other.

I could have stayed and talked to Mr. Dosa for hours, but it was very late now and my ride was leaving. Needless to say, I was completely stunned by what I had seen that evening and over the next several months and years, I must have made quite a pest of myself often keeping Mr. Dosa on the phone for long periods asking questions and listening to his patient explanations. From our first meeting in 1966 until I left for the Naval Academy in 1972, I met and worked with Mr. Dosa at RRS meetings and at rocket firings in the desert many, many times. Each and every time, it was a great joy to see him, talk to him, and learn from him. 

When I left for the Navy in the summer of 1972, “George” as he now had me call him, told me that he had been in the U.S. Navy during World War 2. He had met his lovely wife, Ann, overseas and brought her back home after the war. He wished me the best of luck in the Navy and asked me to stop by and see him whenever I got back to southern California.

After being gone for 18 years, I did find my way back to an RRS meeting and renewed my old acquaintance with George. In the intervening almost two decades, he had changed very little and was still as welcoming, enthusiastic, and as patient an instructor as ever. In the early 1990’s, I volunteered to restart publication of the long dormant RRS News. George was more than a little excited as he was always a huge proponent of documenting all of the projects that RRS members undertook. We began a very enjoyable and several year collaboration writing, editing, and publishing the RRS News more or less, once a quarter. 

During that same time frame, a few members of the RRS and I had started teaching a solid propellant class. As part of that class, several of us had written a course handbook. At the beginning of that course book, Niels Anderson and I had written a dedication to George because of his long, tireless mentoring of so many students and RRS members over the years. I include it here because I believe it captures the essence of who George was within the Society…


“Since the days of Dr. Robert Goddard, the United States has always had its share of rocket enthusiasts and experimentalists. In 1943, even before the end of the Second World War, the young students who founded the Reaction Research Society were hard at work experimenting with propulsion systems. As the “Space Age” dawned, the imaginations of millions were fired with the possibility of flight beyond the atmosphere of Earth. But to members of the many amateur rocketry groups forming during those days, flights of the imagination were not enough. Those with the interest, drive, and courage to try, designed and built fantastic rockets that exploded out of their launch towers on towering pillars of fire and smoke. These were not cardboard models with minuscule motors producing ounces of thrust. These were thundering metal machines, many feet long, producing thousands of pounds of thrust, and flying into the clear desert skies at unbelievable speeds. 

It was a great time of advancement, adventure, and experimentation. Some of those who built these great, unforgiving machines also became the mentors for hundreds of others who followed. These special few not only pursued their own projects, but stopped to share what they had learned with others. Guiding, advising, encouraging, they were tireless in their belief that there was much to be learned in the pursuit of amateur rocketry and they helped all who came and asked. Amateur rocketry, as a whole, owes a debt of gratitude to the few who trained and directed those of us too young and full of wild enthusiasm for our own good. They taught us many things, fed our enthusiasm for learning, encouraged us through failures, and kept us safe all the while with their knowledge and experience. 

This course is dedicated to one such man, Mr. George Dosa. George has been an active rocket propulsion experimentalist for many years. In many ways, he can truly be considered one of the founding fathers of experimental rocketry. George Dosa was the state of California’s first licensed solid propellant rocket pyrotechnic operator. He has been the back-bone of the Reaction Research Society for the last 38 years and still serves today as the Director of Research for the RRS. 

George has dedicated his life to the continuance, advancement and testing of experimental rocket propulsion systems. He represents the very essence of the golden years of experimental rocketry and has crusaded to preserve the right of new experimenters to follow this fascinating and technical hobby. Giving generously of his own time, he has contributed greatly to the education and encouragement of others. As a consequence, the Reaction Research Society would like to thank George by dedicating this first in a series of amateur rocketry propulsion classes to him personally and to his efforts in behalf of amateur rocketry over the years. ” 

Niels Anderson and David Crisalli, March 1996


George told me once that he had been born 30 years too early…he would have liked to have been that much younger when the age of rocketry began to blossom in the 1950’s and 1960’s. From my standpoint, George was born at exactly the right time. Had he been born later, we might not have met and worked together as we did. George lived for nearly a century and all through that time he was a kind, patient, and enthusiastic teacher, a gentle man with dreams of exploring the heavens. I will miss him greatly and I will say farewell (for now) with an old nautical expression….I wish you fair winds and a following sea, George. In a twinkling of God’s eye, we will meet again.

Most sincerely, 

David E. Crisalli, August 2019


David Crisalli is a lifetime member and former President of the RRS. He also is the owner of Polaris, Inc. in Simi Valley, California, a rocket propulsion testing and consulting company.

In Memory of George Dosa (1922-2019)

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.

George Dosa serving in the U.S. Navy in World War 2

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 makes a presentation on rocketry at TRW in the 1960’s

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 Dosa and Marianne Butterfield at the RRS MTA
Richard Butterfield and George Dosa at the RRS MTA in 1987
George Dosa (far right) in his characteristic hat at the 50th anniversary symposium of the RRS in 1993.
George Dosa at the 2017 RRS symposium.

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.

George Dosa in a recent undated photo.

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.

George Dosa being laid to rest with US Navy present
from left to right: Jim Gross, Larry Hoffing, Chris Lujan, Osvaldo Tarditti, Frank Miuccio, George Garboden, David Crisalli, Dave Nordling, John Mariano, John Krell, Chip Bassett

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.

August 2019 meeting

by Dave Nordling, Secretary, RRS


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.

Drew and Arthur Cortopassi attend the August 2019 meeting of the RRS

We began our meeting with the call to order ambien online and reading of the treasury report. This August meeting would try to catch up on topics intended for past meetings.

[1] 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 stromectol over the counter 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.

UCLA supports high school rocketry, the RRS was glad to host two events at the MTA in July 2019.

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.

Jack’s mom carefully folds and stows the streamer payload which would be the first deployment after the booster reaches apogee somewhere near 50,000 feet. The Oswald family was a big part of making this flight possible and the vehicle integration went quite smoothly even clomid in the August summer heat of the Mojave Desert.

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.

Cooper Eastwood, Jack Oswald and Prof. Barsoum Kasparian (holding the booster igniter) inside the George Dosa building at the RRS MTA

Unfortunately, the “50 for 50” rocket flight was a failure and the booster exploded shortly after ignition https://evimaz.com/modafinil-without-prescription/. 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.

The 50 for 50 rocket just after ignition and lift-off. This is the last frame before the booster disappears into a cloud of debris and smoke shattering the launch rails into a twisted mess.

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.

Initial frame taken from the observation bunker as the “50 for 50” booster shatters in the rails throwing the payload upward with the streamer and parachute coming out

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 https://www.elanmedspa.com/ambien-insomnia-treatment/ 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.

John Newman of FAR standing next to the damaged rail launcher examines an unburned grain fragment from the “50 for 50” booster.

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.

Brian Johnson goes over the trajectory analysis based on video footage of the July 13 flight of the Compton alpha rocket. Kent Schwitkis performed this analysis using a physics software package which provided reasonably good results given the number of potential difficulties in using an optical measurement approach.
The trajectory data plotted in Excel showed a clean acceleration pattern which matched expectations from past testing of the alpha.

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.

[2] 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.

[3] 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.

[4] 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.

[5] 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.

John Krell shows his latest breadboard model of his alpha instrumentation package.

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.

Brian Johnson’s alpha payload designed to fit inside the aluminum nosecone of an RRS standard alpha.

[6] 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.

IN CLOSING

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.

Mohammed Daya shows Osvaldo Tarditti and Wilbur Owens the two model rocket bodies he bought at a swap meet. F and G type commercial motors look to be the right size.

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.

secretary@rrs.org