February 2022 virtual meeting

by Keith Yoerg (RRS Secretary)

The latest meeting of the Reaction Research Society took place via video call on Friday, February 11th and had eighteen attendees.

Screenshot of discussion during the monthly meeting


The meeting kicked off with a discussion of the static fire that was to be conducted the following day at the MTA. Osvaldo Tarditti will be the Pyro Op in charge. The wear and tear of testing has become evident on the concrete pad near the vertical test stand, and a question was raised about the best option for future tests by USC at the MTA. Some RRS members raised concerns about any additional drilling into the concrete, and have expressed a desire to eliminate the tripping hazard of permanent bolts. One option discussed and preferred by some members was launching in a vertical orientation. Other members prefer the horizontal orientation that USC has been using.

All members agreed that safety is the #1 priority. John Krell recalled having a friend die in the 60s from fragments of a metal casing that exploded. USC uses a carbon fiber casing, which produces much less dangerous fragments in the event something goes wrong. Fiberglass was mentioned as another alternative safer than metal.


We received another reminder to pay dues for 2022 from the Treasurer:

  • $40/year for full members was due on January 1st
  • $20/year for student members
  • Pay via PO Box or “Donate” button to the right


Joel Cool-Panama and Manuel Marquez presented on the progress of the “Compton Comet.” This RRS project utilizes a 1,500 lbf LOX/ethanol engine. The rocket is under construction at Tomorrow’s Aeronautical Museum at the Compton/Woodley Airport.

Slide from the presentation on the Compton Comet

Both presenters (Joe & Manuel) are RRS members and students at CSU Dominguez Hills. The hopes are to complete a static fire of the liquid rocket engine at the MTA sometime this year.


The discussion then moved to the progress on site upgrades and maintenance: namely the new bathroom and the repair of the Dosa Building window that was broken during Bill Inman’s destructive propane bottle test. On the bathroom front, there was little progress to report. Dimitri is taking the lead on bathroom construction but had been working on pyrotechnics for the Los Angeles Super Bowl, which understandably left little time for the bathroom construction. Progress is expected to pick back up in the upcoming weeks.

Osvaldo outlined the plans he had to repair the glass in the Dosa building. Because this is not the first time a window had to be replaced, Osvaldo designed an aluminum frame which locks into place and allows removal and replacement of the pane from inside the Dosa building. He intends to install a plexiglass panel in the place as a test. It would likely be more resistant to shattering, but may get cloudy or present other unforeseen issues. The only way to find out is to test it!


As mentioned earlier in this post, Bill Inman conducted an elevated temperature burst test of a 5-gallon (20-pound) propane container partially filled with water. A detailed report on that test from Bill can be found here.


Earlier in February, UCLA planned 3 liquid rocket engine tests in a single day – an ambitious goal. A summary of the day from the Pyro Op in charge, Dave Nordling, can be found here.


The executive council approved a new fee structure for use of the MTA, which are specific to non-RRS members. RRS members are still allowed to use the site with the usual requirements in place. The new fee structure is as follows:

  • $1,000 / day for schools
  • $1,500 / day for private companies

A minimum 14-day advance notice is required, and reservations are subject to availability of Pyro Ops qualified to oversee the testing taking place.


The MTA has a busy several months coming up. Frank updated the membership on the student classes, a new set of which will begin on the 23rd of February for the LAPD Strive class. Classes are scheduled once a week through March with the launch on April 2nd. Another set of classes with the YMCA will begin in early April, with a similar schedule and a launch date set for May 1st.

The University of Michigan has requested the MTA be reserved for a testing campaign on a LOX-RP1 liquid rocket engine from May 6th – 13th. USC has also expressed interest in conducting further testing in the near future.

Wolfram Blume updated the membership on his project the “Gas Guzzler.” He is finalizing the re-build of the parts damaged in the last flight and hopes to have the repairs complete in late-February, with a new launch shortly thereafter.


Chris Lancaster has been corresponding with a museum in Germany who has one of George Garboden’s rocket motors installed in a racecar. They are preparing a presentation for the March meeting about this machine of interest!

The next RRS monthly meeting will be held virtually on Friday, March 11th at 7:30 pm pacific time. Current members will receive an invite via e-mail the week of the meeting. Non-members (or members who have not received recent invites) can request an invitation by sending an email to:


Please check your spam folders and add secretary@rrs.org to your email whitelist to make sure you are receiving the meeting invitation.

October 2021 Virtual Meeting

by Dave Nordling, RRS.ORG

The Reaction Research Society held it’s monthly meeting by teleconference on Friday, October 8, 2021. Some of our members were on travel, but the those in attendance were able to discuss several important issues.

The USC RPL static fire event on 9-26-2021 was safely conducted but ended in a explosion and fire which was ably contained. This was a good example of careful preparations and good management of the people present for the event. A firing report has been posted for this event. Osvaldo Tarditti was the pyrotechnic operator in charge that day.

UCLA had requested the use of the MTA on 10/16/2021 for their next liquid rocket engine test. The MTA was already reserved for Bill Claybaugh’s solid rocket flight that same day and in the days leading up to the event. Dave Nordling was the pyro-op in charge, A firing report for this event will be posted,

UCLA is planning to hold their conceptual design review (CoDR) on 10/22/21 for the next iteration of their liquid rocket. RRS members Dave Nordling and John Krell plan to attend.

Wolfram Blume was on the call and said he was eager to return to the MTA for a second flight attempt of the Gas Guzzler ramjet. With the summer heat gone, he hopes to return at our next launch event which is still being planned. It is hoped that the society can continue their streak of having at least one MTA event per month as we have done since the start of 2021.

The restroom container was purchased and brought to the Compton Airport for interior construction. This 20-foot high cube has a 9.5 foot ceiling and should be able to have two individual rooms with toilet and sink, one of these to have a shower stall. Osvaldo had drafted a floor plan and this was approved by the council. The society will be meeting at the Compton Airport on Saturday, October 23rd, for a late morning barbecue and an in-person discussion of the materials needed to get the restroom interior built. All members are welcome but please notify Keith, Wilbur, Xavier or Dave Nordling if you’re coming as they have access to the airport.

RRS containerized restroom awaits interior design and build

There was some discussion about the septic system and leach field. It is important to maintain an appropriate distance from any nearby water wells, one of which is on Polaris Propulsion property. Sufficient clearance exists based on measurements made and EPA guidelines. The leach field will be positioned to drain away to the north.

The society is considering buying a concrete septic tank but RRS member Wilbur Owens may have a plastic septic tank already available for the society. Some members feel a concrete septic tank will last longer and be less likely to leak. The council is still debating this feature and should render a decision soon.

The society also discussed the water supply to the restroom container and the supporting structure needed to hold a tank on top of the container. There are many important facets to this infrastructure addition which must be weighed carefully.

Nominations for RRS executive council offices will be held at next month’s meeting, November 12th, 2nd Friday of the month at 7:30pm. An election chairman will be selected beforehand and this person must be an active member not holding office nor running for office. A special email address will be set up for the election chairman to gather votes from our active administrative and lifetime members. Results to be announced at the December 10th meeting and new terms to start January 1, 2022.

For any questions, please contact the RRS secretary.


September 2021 Virtual Meeting

by Keith Yoerg (RRS Secretary)

The latest meeting of the Reaction Research Society took place Friday, September 10th and had 16 attendees, including several members of the University of Michigan Aeronautical Science Association (MASA) team which conducted a long campaign of testing at our MTA site last month. After brief hellos & a short discussion on updates to this website, we got the meeting rolling with a presentation from the MASA team debriefing us on their August tests.

Screenshot of discussion during the monthly meeting


4 members of the MASA team who were present for the long campaign of testing at the MTA site were at the meeting and provided a presentation detailing how the nearly 2 weeks of work went for the team. A detailed write-up from RRS member Dave Nordling who was on site assisting for some of that time is available here.

MASA logos – Tangerine Space Machine is named after a craft brewed beer local to the Michigan area

While the end goal of conducting a hot fire test was not accomplished, there was a ton of great work and learning opportunities for both the MASA team and the RRS. The first challenge for the MASA team was in driving their equipment all the way from Michigan to Southern California. Unfortunately, they had some equipment suffer damage during the trip when their smaller “Ground Support Equipment” (GSE) trailer broke through the plywood floor of their larger travel trailer. This required them to stop in Texas and complete repairs to the travel trailer before continuing on to the MTA site.

Once at the site, the MASA team set up a 2-shift schedule (9am – 6pm and 5pm – 12am) effectively working 18-hour days to conduct the activities required for their tests. Many of these tasks took a lot longer than the team had anticipated, in particular with the supply and delivery of the gas & cryogenics needed. The MASA team was originally in contact with Airgas, but their communication was with the office closer to their home in the Midwest and not the Southern California branch. Ultimately sorting through those issues proved to be too difficult to secure a delivery while the team was at the MTA, but fortunately they were able to work with Praxair to secure a supply of the gas and cryo.

MASA presenting a great photo of nighttime work at the MTA to the members at the September meeting

Once the gas and cryogenics were at the site, the team was able to complete pressure tests of the fuel side of the system, and were ultimately able to perform 2 coldflow tests through the entire system near their target pressures. These tests revealed many more areas for design improvements that the team hopes to implement, including reducing fittings, changing the location of vents and drains, and possibly even replacing the LOx and fuel tanks.

Improvements the MASA team hopes to implement

This campaign goes down in the books as the longest to ever take place in RRS history, and proved to be challenging for both the MASA team and the RRS. Several society members graciously volunteered their time to help make this testing effort possible, and the experience revealed many ways that the society could improve our procedures to better support extensive tests like this. Namely: limiting the duration of a test period to no longer than 1 consecutive week, requesting that some members of University staff be on-site when these long campaigns take place, and requiring a longer notice time before approving this sort of test were all brought up by RRS president Osvaldo.


Progress is continuing on the permanent RRS Bathroom structure. Work on cutting holes for doors and windows has been completed on the 20-foot shipping container and delivery is expected imminently to the new work site at Wilbur’s hangar. The next stages of construction including adding plumbing, fixtures, and the doors and windows, and Osvaldo has already acquired some of these items to install

View from inside the container with the doors and vent windows installed


The USC Rocket Propulsion Lab (USCRPL) plan to be out at the MTA site from Friday, September 24th – Sunday, September 26th to conduct a static fire of an 8″ diameter solid rocket motor. The first few days will consist of prep work and the firing is planned on that Sunday. Several members including Bill Inman and John Krell indicated in the meeting that they have stepped up to the Yoerg Challenge and built model rocket kits to fly at the MTA. This will give us a great excuse to test out the new PVC wire rail launchers as well as the newly purchased Cobra wireless firing system.

In addition, the society has decided to use Sunday, September 26th as the date for our annual “Work Party” to perform maintenance and cleaning tasks at the MTA site. The expected tasks we would like to complete are:

  • Weld the plate on the vertical test stand
  • Removal of dry vegetation
  • Move drum of RP1 (from MASA testing) into one of the lockable containers
  • Fix the 2 broken latches on the Dosa Building roll door
  • Prep/measurements in area for new container bathroom


RRS Vice President Frank updated the membership on the upcoming youth rocketry class in Boyle Heights with details on the schedule and overall plan. As opposed to 2 alternating classes, we will now be working with a single class of up to 30 students. The classes will run every Friday starting on September 24th, with a launch planned at the MTA site on November 13th. The plan is for each student to build their own Estes Baby Bertha kit and fly it twice on launch day. RRS Secretary Keith is currently working on 3D printing fin alignment jigs for the students, which will help in both teaching the students about that technology as well as properly installing straight & aligned fins on their rocket kits.

Several of the 3D printed fin alignment jigs


The end of the meeting consisted mostly of miscellaneous discussions around the various projects that RRS members are currently working on. Some of the highlights included John Krell’s new, very small (20x80mm) electronics board capable of collecting 7 channels of data onboard a flight, with over half of those channels at 500 Hz! Bill Inman updated members on the progress with his Solar Cat steam rocket, and there was a brief discussion of ham radio operations with Tom Hendricks sharing some of his wealth of knowledge in that subject. Overall it was a fun meeting with a lot of good discussion & participation from the membership.


The next RRS monthly meeting will be held virtually on Friday, October 8th at 7:30 pm pacific time. Current members will receive an invite via e-mail the week of the meeting. Non-members (or members who have not received recent invites) can request an invitation by sending an email to:


Please check your spam folders and add secretary@rrs.org to your email whitelist to make sure you receive the invitation.