MTA launch event, 2019-09-21

Larry Hoffing, Events Coordinator, RRS

Photo credits: Osvaldo Tarditti

The Reaction Research Society held another launch event with the LAPD CSP. This event was with the students of Boyle Heights. We had ten standard alphas launched into the blue Mojave sky that day including some model rockets made by Russell Hoffing and my grandson.

A lot of different groups came out for this launch event at the RRS MTA, 09-21-2019

We had students from the CSU Long Beach liquid rocket team come out to make some measurements for sub-system testing that they are planning at the RRS MTA this year.

CSU Long Beach inspects the vertical mounting structure at the RRS MTA
Model rockets in the George Dosa building undergoing preparation for launch
Students from Boyle Heights get their orientation instructions at the RRS MTA
RRS events coordinator, Larry Hoffing; RRS VP, Frank Miuccio and RRS president, Osvaldo Tarditi

Returning RRS member, John Krell, had worked up two prototype instrumentation packages for flights in the ninth and tenth RRS standard alphas on that day. Both rockets were recovered and the results were impressive.

John Krell arms his payload integrated into one of two RRS standard alphas, 09-21-2019
One of John’s prototypes survived the flight and is laid out on the table in the Dosa Bldg.
John Krell examines the recovered SD memory chips to determine the flight profile from the RRS alpha. Over 100 G’s of acceleration at take-off max’d out the sensor!

Materials have been acquired to repair the adjustable rail launcher that was damaged in early August this year. Osvaldo has been busy at work on the repairs. The RRS has several facility improvement projects in the works and we hope to bring this rail launcher back to service soon for larger rockets (4 to 6 inches).

John will hopefully have a full report and an overview of his design. Both Bill Behenna and Brian Johnson are also working on their own instrumentation designs for the RRS standard alpha. With this recent progress, this should help our others members take better data.

Still photo from RRS alpha #3 of 10 launched at the MTA on 09-21-2019.

We’ll discuss more of the results of this event in detail at the next RRS meeting on October 11, 2019. The RRS meets every 2nd Friday at the Ken Nakaoka Community Center in Gardena, California. Stop in and see how things went.


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.

July 2019 meeting

Dave Nordling, RRS Secretary


The RRS held their monthly meeting on July 12, 2019, at the Ken Nakaoka Community Center in Gardena. We had a very large turnout with over 26 people coming in to see the three different presentations we had and catch up on the latest news.

After our reading of the treasury report, we had a special announcement of the induction of five new administrative members to the RRS. Our society is growing and this is in large part to the great participation we’ve been having and the dedication of the many talented people at the RRS.

Larry Hoffing gave us a short summary of the UCLA Rockets project he supervised at the RRS MTA. This Wednesday, July 10th, event was the first since the pair of earthquakes that rattled the nearby town of Ridgecrest in the Mojave. The RRS is happy to report none of our structures had any significant damage and the MTA is very much ready to operate.

We next discussed the upcoming launch event at the MTA tomorrow with Operation Progress in Watts with the LAPD CSP. We’ll have several alphas and a beta launch. We also plan to have an alpha with a parachute recovery system put together by new member, Kent Schwitkis and his friend Brian.

RRS vice president, Frank Miuccio, has started a new educational program this week with the students of Boyle Heights. There will be 10 teams launching their rockets from the MTA in September.

RRS alpha outfitted with a 36-inch parachute
Two alpha payload tubes with the nose cone and couplers installed. Reused parts from recovered alpha rockets.

Our first presenter was Kent Schwitkis who brought several of his students from Compton College to our Friday night meeting. Kent is a member of the Sierra Club and Ski Patrol and has many years of experience with wilderness survival and first aid. His presentation outlined the important of planning for many kinds of potential emergencies. One of the important results from this discussion was the need for the RRS to form a safety committee to begin preparing emergency plans and establish contact with the regional authorities in preparing to handle serious emergencies if the need would ever arise.

Kent Schwitkis and Waldo Stakes before the July 2019 meeting

The second presenter we had at the meeting was Sam Austin, a senior at MIT. Sam presented his two-stage solid rocket design to reach the von Karman line.

Sam Austin (right) presents his booster and second stage design for his solid rocket

Sam also detailed the kerosene-LOX liquid rocket design that was test-fired at FAR in January 2019. Although the test was short (3 seconds), his results were impressive and his injector survived intact..

Sam’s liquid rocket injector which was modified for 1500 lbf of thrust

The last presentation was by RRS members, Jack Oswald and Cooper Eastwood. They have been steadily improving their solid motor design and have fabricated their improved motor based on prior tests. Their goal is to reach the 50,000 foot altitude limit at the RRS MTA on July 20th. His “50 for 50” rocket is 12 feet tall and 5-inches in diameter built entirely from scratch. The launch is to be timed with the 50th anniversary of the Apollo 11 moon landing.

Jack and Cooper detail the progress they’ve made and their solid motor ready for flight from the RRS MTA on July 20th.

The solid rocket holds 30 lbm of APCP propellant with an estimated burn time of 3 to 4 seconds generating an impulse of 7000 lbf-sec. The rocket fully loaded is 84 lbm and should reach a peak acceleration of 30 G’s and a burnout velocity of Mach 2.5 as it reaches 50,000 feet.

A 100-foot drogue streamer will deploy from the recovery system followed by a 9-foot Apollo 11 replica parachute at 2000 feet. The flight events are driven by an upgraded classic flight computer from Eggtimer and an RRC3 dual deployment system from MissileWorks. The von Karman nosecone is 3D printed and the aluminum fin can was rolled onto the aluminum body to be painted in polished black and white pattern of the Apollo 11 vehicle.

The RRS looks forward to the successful flights of Sam and Jack’s rocket from FAR and the RRS MTA, respectively. Both will be on the 50th anniversary of mankind’s greatest achievement on July 20th.

If there are any questions or corrections, please contact the RRS secretary. The next meeting of the RRS will be August 9, 2019.