by Dave Nordling, President, Reaction Research Society
The Reaction Research Society held its monthly meeting by teleconference on June 10, 2022. The meeting covered several recent topics and we welcomed new member, Rushd Julfiker.:
We discussed the two recent events at the RRS MTA. Firing reports have been posted for each.
5/21: YMCA student launch event
6/4: UCLA Senior Capstone project launches
The society has had a few groups interested in using the MTA in the next month. Formal requests to use the MTA must be sent by email to the RRS president with specific dates requested.
Dimitri Timohovich and Osvaldo Tarditti went to the MTA on Sunday, 6/5/22 to disassemble and examine the condition of the loader used at the MTA and owned by member, Wilbur Owens. The hydraulic cylinders will require a complete rebuild to return the machine to working order. The backhoe and loader has been a very useful asset to the society and as such the repairs will be paid by the society. Our security cameras are working well to monitor the site in our absence.
The 40th annual Large and Dangerous Rocket Ships (LDRS40) event by the Tripoli Rocketry Association is being hosted by the Rocketry Organization of California (ROC) in Lucerne Valley this weekend. Some of the RRS will be attending. it is an excellent event that brings many groups together and this year it is back in southern California.
Progress is being made on the new restroom facility. The septic system and leach field will go in soon. Dimitri provided updates on the container interior which should be finished by month’s end. The next step will be adding the roof platform and water tanks followed by completing the electrical systems.
Site maintenance and upgrades were discussed for projects after the new restroom facility is complete including more water storage and fire suppression gear. We could also use some metal cabinets and industrial shelving to better organize the contents of our new 40-foot storage container.
We have had a persistent problem with nails and metal debris puncturing tires at the MTA. One solution to this problem is a magentic sweeper which can pull up and remove any iron pieces left in the shallow layers of sand and dust.
The society has bought two of these devices. With some dedicated and coordinated efforts, our site can be cleaned of this hazard. We will be asking our membership to spend some time sweeping the MTA, collecting the findings and disposing of them in the burn pit.
The society has bought a new 1-ton gantry crane, trolley and chain hoist. This equipment will be useful in loading and unloaiding heavy materials on and off pickup trucks. Items such as cryogenic liquid cylinders would benefit from having a simple means of lifting them on and off with no power source required. The gantry crane will have the wheels removed and will be permanently mounted to a fixed foundation at the north pad by the Dosa Building.
After some consideration, the executive council decided it would be best to postpone the next RRS Symposium until the spring of 2023. It takes a significant amount of preparation and we felt it best to wait to begin in the new year when we will celebrate our 80th anniversary. Before the pandemic, we had three increasingly successful annual events and we look forward to restarting them soon.
Next meeting will be July 8th as they happen on every 2nd Friday of the month. Our meetings will remain by teleconference but we are checking with the Ken Nakaoka Community Center about returning to in-person meetings soon. We will continue to have the teleconference feature even after we return to in-person meetings.
To attend our meetings, contact the RRS secretary.
by Frank Miuccio, Vice President, Reaction Research Society
The RRS held a launch event at our private testing site, the Mojave Test Area (MTA) on Saturday, May 21, 2022. Larry Hoffing was the pyrotechnic operator in charge. Temperatures were still mild and below 90 Fahrenheit. Winds were very slight for the entire event,
The main event was the launch of a number of student built model rocket kits using commercial motors. The second planned event was a member project, the two-stage Gas Guzzler ramjet, by Wolfram Blume. The third event was a cryogenic liquid tanking test at the vertical test standt of a portion of the Compton Comet liquid rocket overseen by Dave Nordling and Waldo Stakes.
The RRS teamed up with Boyle Heights YMCA and taught the students about rocketry over several weeks before the launch event. These students were the ones involved with the YMCA’s robotic program. We had 22 students come out to the MTA. During this launch day, we launched 23 Baby Bertha rockets all built from kits and custom painted by the students.
These rockets were launched first with smaller A8-3 engines. The students then retrieved their rockets and went into the Dosa Building and reassembled the parachutes for their next launch. The next launch was done with a larger C6-5 engine. All went well for the day.
We were able to use the new launch racks built by Dimitri Timohovich which gave us the capability to set up 18 rockets at a time which was our channel limit of our Cobra launch system. We have made a great investment with this safe and convenient product and more of our pyrotechnic operators are getting trained in its use thanks to Keith Yoerg.
The Boyle Heights YMCA wants to continue doing classes with the RRS. The students had a great experience.
The second event of that day was Wolfram Blume’s next attempt to launch the Gas Guzzler for its second flight. Significant design improvements were made. This very ambitious project is the result of a lot of complex design and 3D-printed parts which must fit correctly into their respective assemblies. Unfortunately, a critical fit problem with the nose piece prevented Wolfram from completing the build despite some on-the-spot adjustments. He postponed the flight to conduct minor repairs back at his home workshop. Wolfram plans to return to the MTA on June 4th at our next launch event with the UCLA Capstone Project.
The third operation at the MTA was a cryogenic liquid tanking test. The Compton Comet is a large liquid rocket being built by students and former students of Compton College. Led by Dave Nordling and Waldo Stakes, it is a project supported by the RRS and each person on the team is a member of the society. The Compton Comet describes both the vehicle which will be built and flown by the student members of the society and the team, itself. The ethanol/LOX vehicle uses a surplus 1500 lbf thrust chamber from an RM6000-4-1 engine once used to power the Bell X-1. The project is still in the latter parts of the design phase and important component testing is essential before committing more resources to construction. Bill Inman assisted with some of the operations that day.
The Compton Comet uses a pair of surplus stainless steel oxygen aircraft tanks. With the two tanks joined in series, a cold shock test with liquid nitrogen was done to verify their integrity after some minor welding was done. These tanks are decades old but have passed hydrotesting and visual inspection at the welded connections. These operations gave the student members hands-on experience with the safe transfer of cryogenic liquids. The society has acquired personnel protective equipment (PPE) such as polycarbonate faceshields, long elbow-length gloves and long cryogenic aprons to help future projects.
RRS member Diana Castillo recorded the time of each event and observations of the team as the tanking test progressed. The cryogenic liquid loading in uninsulated tanks is a slow process that loses much liquid to boiling. Eventually liquid nitrogen does accumulate in a tank if sufficient flow and capacity is available. The tank was vented at the top throughout the testing. A cryogenic rated relief valve to be used later in the full static fire was also present.
The second objective of this test was to demonstrate the pilot-operated solenoid valves intended for use as the main propellant valves of the vehicle. One of these high-pressure rated, normally-closed angle valves was connected at the bottom of this dual-tank setup. Cryogenic temperatures have been known to cause failures in electrical equipment. After attempting to fill the lower tank and having a significant amount of liquid nitrogen sitting at the inlet, the solenoid valve was well chilled for this functional test.
Before cryogenic loading, the valve was tested at ambient conditions using a pair of 12 VDC gel cells strapped in series to get the full 24 VDC needed to actuate the pilot solenoid. The circuit was switched by manually connecting the positive terminal by alligator clips. The distinct popping sound of the core stem moving inside was easily heard and very repeatable.
With the valve fully chilled after 40 minutes elapsed, the valve was tested again and functioned reliably. This is an important validation of the solenoid working in a relevant environment. The angle valve’s internal spring is very large and will require significant inlet pressure (150 psi?) to open. It was decided to leave the tanks vented at all times during this initial cryogenic liquid filling operation and leave a flow test for later. There were no signs of leakage from the valve outlet which was also a good result.
The Compton Comet project team recorded and discussed their findings. Leaving the tank vented, the liquid nitrogen boiled away in the warm afternoon. The remaining members enjoyed some time in the Dosa Building eating grilled burgers and hot dogs made by Waldo Stakes. Dimitri was able to reinforce the metal support legs of this donated propane gas grill to continue its service to the society.
The society cleared the areas and stored our gear. The next MTA event will be June 4th with the UCLA Senior Capstone Project. Wolfram Blume will return to fly the Gas Guzzler for a second flight. Dave Nordling will be the pyro-op in charge. Any other member projects are welcome and they should contact the RRS president to schedule them.
by Keith Yoerg, Secretary, Reaction Research Society
The society held its monthly meeting for March on Friday, the 11th, at 7:30pm by teleconference.
The following items were on the agenda.
Chris Lancaster’s presentation on rocket bikes and drag racing history
Review of recent MTA events, USC RPL static fire
Upcoming events at the MTA
Delivery of new 40-foot storage container by Dimitri Timohovich
Site maintenance and upgrades
Wolframe Blume’s next flight of the Gas Guzzler
Bill Inman’s testing for steam rocketry
Low power launches
Upcoming university event requests and inquiries
USC RPL static fire and flight
University of Michigan, MASA in May 2022
UC Irvine and Cal Poly Pomona
Student classes and launches
LAPD CSP – STRIVE event, 4/2/2022
YMCA classes, launch on 5/1/2022(?)
RRS post office box, renewal and other options
We spent the majority of our time on the subject of early rocketry in drag racing and rocket bikes. Chris Lancaster of Pennsylvania spent an extraordinary amount of time researching this subject and the specific rocket bike built by Henk Vink now on exhibit in Germany. A stand-alone article on this topic may be forthcoming.
The MTA firing report from 3/12/2022 covers the events from that day following the meeting. The anticipated events were discussed at the meeting.
The RRS will continue to keep our post office box in Los Angeles (Inglewood) 90009 for another year. The annual cost has been rising but it remains well used for correspondence.
Reaction Research Society; P.O. Box 90933; Los Angeles, CA, 90009
Our director of research, Richard Garcia, agreed to investigate LNG safety guidelines with regard to flaring of this volatile fuel in amateur rocketry applications. He will submit his findings to the council for internal peer review. The RRS will be creating a policy on this issue as some amateur liquid rocket projects intend to use natural gas (largely methane).
Further updates to this meeting report are forthcoming.
Next meeting will be April 8th. For those interested in attending, contact the RRS secretary.